U.S. patent application number 08/811220 was filed with the patent office on 2001-07-19 for process and apparatus for recovering components of sealed type battery.
Invention is credited to ASAO, MASAYA, KAWAKAMI, SOICHIRO, KOBAYASHI, NAOYA.
Application Number | 20010008723 08/811220 |
Document ID | / |
Family ID | 26414210 |
Filed Date | 2001-07-19 |
United States Patent
Application |
20010008723 |
Kind Code |
A1 |
KAWAKAMI, SOICHIRO ; et
al. |
July 19, 2001 |
PROCESS AND APPARATUS FOR RECOVERING COMPONENTS OF SEALED TYPE
BATTERY
Abstract
A recovering process for recovering the constituent components
of a sealed type batter comprising at least an a cathode, an anode
and an electrolyte sealed in a battery housing, characterized in
that said process includes a step (a) of decreasing the ionic
conductivity between said cathode and anode of said sealed type
battery and a step (b) of opening said battery housing of the
sealed type battery after conducting said step (a). An apparatus
suitable for practicing said recovering process.
Inventors: |
KAWAKAMI, SOICHIRO;
(NARA-SHI, JP) ; KOBAYASHI, NAOYA; (NARA-SHI,
JP) ; ASAO, MASAYA; (TSUZUKI-GUN, JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
26414210 |
Appl. No.: |
08/811220 |
Filed: |
March 5, 1997 |
Current U.S.
Class: |
429/49 |
Current CPC
Class: |
Y02W 30/84 20150501;
H01M 10/30 20130101; H01M 10/06 20130101; H01M 10/54 20130101; H01M
10/052 20130101; H01M 10/345 20130101; Y02E 60/10 20130101 |
Class at
Publication: |
429/49 |
International
Class: |
H01M 010/54; H01M
006/52 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 5, 1996 |
JP |
073081/HEI.8 |
Dec 24, 1996 |
JP |
355438/HEI.8 |
Claims
What is claimed is:
1. A recovering process for recovering the constituent components
of a sealed type batter comprising at least an a cathode, an anode
and an electrolyte sealed in a battery housing, characterized in
that said process includes a step (a) of decreasing the ionic
conductivity between said cathode and anode of said sealed type
battery and a step (b) of opening said battery housing of the
sealed type battery after conducting said step (a).
2. A recovering process according to claim 1, wherein the sealed
type battery has an electrolyte solution as the electrolyte between
the anode and cathode, and the step (a) is conducted by extracting
the electrolyte solution or the solvent of the electrolyte solution
outside the battery housing.
3. A recovering process according to claim 2, wherein the sealed
type battery has a safety vent, and a differential pressure is
caused between the inside and outside of the battery housing to
actuate said safety vent, whereby extracting the electrolyte
solution or the solvent of the electrolyte solution through said
safety vent outside the battery housing.
4. A recovering process according to claim 3, wherein a portion of
the sealed type battery where the safety vent is provided is
positioned to face in a downward direction and the electrolyte
solution or the solvent of the electrolyte solution is extracted
through the safety vent outside the battery housing.
5. A recovering process according to claim 2, wherein the
electrolyte solution or the solvent of the electrolyte solution
extracted outside the battery housing is recovered.
6. A recovering process according to claim 1, wherein the step (a)
is conducted by at least cooling the sealed type battery.
7. A recovering process according to claim 6, wherein the sealed
type battery has an electrolyte solution as the electrolyte between
the anode and cathode, and the sealed type battery is cooled to a
temperature lower than the freezing point of the solvent of the
electrolyte solution.
8. A recovering process according to claim 6, wherein a polymer
solid electrolyte solidified using a polymer is used in the sealed
type battery, and the sealed type battery is cooled to a
temperature lower than the glass transition temperature of the
polymer of the polymer solid electrolyte.
9. A recovering process according to claim 6, wherein the sealed
type battery is cooled by using a compressed incombustible gas
comprising one or more kinds of gas selected from the group
consisting of nitrogen gas, argon gas, helium gas, carbon dioxide
gas and fluorocarbon gas.
10. A recovering process according to claim 6, wherein the sealed
type battery is cooled by immersing the sealed type battery in a
cooling agent or liquefied gas.
11. A recovering process according to claim 10, wherein the cooling
agent is a mixture of a dryice and methanol or a mixture of a
dryice and ethanol.
12. A recovering process according to claim 10, wherein the
liquefied gas is liquid nitrogen.
13. A recovering process according to claim 6, wherein the sealed
type battery is immersed in water, the sealed type battery is
frozen together with said water to seal the sealed type battery in
an ice produced, and the sealed type battery is opened in a state
in that the sealed type battery is sealed in the ice.
14. A recovering process according to claim 1, wherein the step (b)
is conducted in an incombustible atmosphere.
15. A recovering process according to claim 14, wherein the
incombustible atmosphere is composed of one or more kinds of gas
selected from the group consisting of nitrogen gas, argon gas,
helium gas, carbon dioxide gas, steam and fluorocarbon gas.
16. A recovering process according to claim 9, wherein the step (b)
is conducted in an incombustible atmosphere composed of the same
gas as that used in cooling the sealed type battery.
17. A recovering process according to claim 1, wherein the step (b)
is conducted by means of a cutting manner selected from the group
consisting of high pressure water cutting, energy beam cutting and
mechanical cutting.
18. A recovering process according to claim 17, wherein the high
pressure water cutting is a cutting manner of spraying a high
pressure water containing an abrasive through a jet nozzle.
19. A recovering process according to claim 17, wherein the energy
beam used in the energy beam cutting is laser beam.
20. A recovering process according to claim 1, wherein the sealed
type battery is a lithium battery in which oxidation-reduction
reaction of lithium ion is used.
21. A recovering process according to claim 1, wherein the sealed
type battery is a nickel-metal hydride battery in which
oxidation-reduction reaction of hydrogen ion is used and a hydrogen
storage alloy is used as an anode material.
22. A recovering process according to claim 1, wherein the sealed
type battery is a nickel-cadmium battery.
23. A recovering process according to claim 1, wherein the sealed
type battery is a lead-acid battery.
24. A recovering process according to claim 20 which further
includes a step of reacting a reacting agent with an active lithium
contained in the lithium battery to decrease the reactivity of said
active lithium after the step (b).
25. A recovering process according to claim 24, wherein the
reacting agent comprises one or more materials selected from the
group consisting of water, alcohols, acids, and carbon dioxide.
26. A recovering process according to claim 20 which further
includes a step of conducting washing the opened lithium battery
with the use of an organic solvent which is conducted after the
step (b).
27. A recovering process according to claim 26, wherein the organic
solvent is an organic solvent incapable producing an azeotrope with
water.
28. A recovering process according to claim 26 which further
includes a step of dissociating the sealed type battery into
individual battery components and recovering the constituent
components of the sealed type battery which is conducted after the
washing step with the use of the organic solvent.
29. A recovering process according to claim 1, wherein the sealed
type battery is sorted depending on the shape or the type prior to
the step (a).
30. A recovering process according to claim 1 which further
includes a step of discharging the electric residual capacity of
the sealed type battery prior to conducting the step (a).
31. A recovering process according to claim 30, wherein in the step
of discharging the residual electric capacity, an energy discharged
is recovered.
32. A recovering apparatus for recovering the constituent
components of a sealed type batter comprising at least an a
cathode, an anode and an electrolyte housed in a battery housing,
said apparatus comprising at least a means (i) for decreasing the
ionic conductivity between said cathode and anode of said sealed
type battery and a means (ii) for opening said battery housing.
33. A recovering apparatus according to claim 32, wherein the
sealed type batter comprises an electrolyte solution as the
electrolyte between the anode and cathode, and the means (i)
comprises a liquid extraction means (i-a) for extracting the
electrolyte solution or the solvent of the electrolyte solution
outside the battery housing.
34. A recovering apparatus according to claim 33, wherein the
sealed type battery has a capping provided with a safety vent, and
the liquid extraction means (i-a) includes a means (i-b) for
causing a differential pressure between the inside and outside of
the battery housing through said safety vent to actuate said safety
vent whereby extracting the electrolyte solution or the solvent of
the electrolyte solution outside the battery housing.
35. A recovering apparatus according to claim 34, wherein the means
(i-b) comprises at least a vessel (i-c) capable of being vacuumed
and which is provided with an exhausting means.
36. A recovering apparatus according to claim 35, wherein the
vessel (i-c) has a member capable of tightly contacting or joining
with an exterior wall face portion of the battery housing of the
sealed type battery, said exterior wall face portion comprising a
portion of the capping, said portion including the neighborhood of
the safety bent, and said member having an opening through which
said exterior wall face portion is communicated with the vessel
(i-c) so that the electrolyte solution or the solvent thereof in
the sealed type battery is capable of being extracted through said
member into the vessel (i-c).
37. A recovering apparatus according to claim 35, wherein a passage
capable of introducing air, nitrogen gas or inert gas is provided
at the vessel (i-c) through a valve.
38. A recovering apparatus according to claim 34, wherein a closed
space comprising a part or the entire of an exterior wall face of
the battery housing including the neighborhood of the safety vent
and the vessel (i-c) is formed such that the safety vent is
situated within said closed space and that the internal pressure of
said closed space is capable of being decreased to be lower than
that of the sealed type battery, wherein the electrolyte solution
or the solvent thereof in the sealed type battery is capable of
being extracted into said closed space.
39. A recovering apparatus according to claim 38, wherein the
closed space is established after the internal pressure of the
vessel (i-c) is decreased to be lower than the atmospheric pressure
by means of an exhausting means.
40. A recovering apparatus according to claim 38, wherein after the
closed space is formed, the internal pressure of the closed space
is decreased to be lower than that of the sealed type battery by
means of an exhausting means connected to the vessel (i-c).
41. A recovering apparatus according to claim 32, wherein the means
(i) comprises at least a means (i-d) for cooling the sealed type
battery.
42. A recovering apparatus according to claim 41, wherein the
cooling means (i-d) is for freazing the sealed type battery to a
temperature lower than the freezing point of the solvent of the
electrolyte solution.
43. A recovering apparatus according to claim 41, wherein a polymer
solid electrolyte solidified by a polymer is used as the
electrolyte in the sealed type battery, and the cooling means (i-d)
for cooling the sealed type battery to a temperature lower than the
glass transition temperature of the polymer of the polymer solid
electrolyte.
44. A recovering apparatus according to claim 41, wherein a
compressed incombustible gas comprising one or more kinds of gas
selected from the group consisting of nitrogen gas, argon gas,
helium gas, carbon dioxide gas and fluorocarbon gas is used in the
cooling means (i-d).
45. A recovering apparatus according to claim 41, a cooling agent
or liquefied gas is used in the cooling means (i-d).
46. A recovering apparatus according to claim 45, wherein the
cooling agent is a mixture of a dryice and methanol or a mixture of
a dryice and ethanol.
47. A recovering apparatus according to claim 45, wherein the
liquefied gas is liquid nitrogen.
48. A recovering apparatus according to claim 41, wherein the
cooling means (i-d) is for immersing the sealed type battery in
water and freezing the enclosed type battery together with said
water to seal the sealed type battery in an ice produced, and the
opening means (ii) is for opening the sealed type battery sealed in
the ice.
49. A recovering apparatus according to claim 32, wherein the
opening means (ii) includes a means capable of making the
atmosphere in which to open the sealed battery is conducted by
means of the opening means (ii) to be an incombustible
atmosphere.
50. A recovering apparatus according to claim 49, wherein the
incombustible atmosphere is composed of one or more kinds of gas
selected from the group consisting of nitrogen gas, argon gas,
helium gas, carbon dioxide gas, steam and fluorocarbon gas.
51. A recovering apparatus according to claim 50, wherein the
sealed type battery is opened by means of the opening means (ii) in
an incombustible atmosphere composed of the same gas as that used
in cooling the sealed type battery by means of the cooling means
(i-d).
52. A recovering apparatus according to claim 32, wherein the
opening means (ii) comprises a cutting means selected from the
group consisting of high pressure water cutting, energy beam
cutting and mechanical cutting.
53. A recovering apparatus according to claim 52, wherein the high
pressure water cutting means comprises a jet nozzle and is a
cutting means for spraying a high pressure water containing an
abrasive through the jet nozzle.
54. A recovering apparatus according to claim 52, wherein the
energy beam used in the energy beam cutting is laser beam.
55. A recovering apparatus according to claim 32, wherein the
sealed type battery is a lithium battery in which
oxidation-reduction reaction of lithium ion is used.
56. A recovering apparatus according to claim 32, wherein the
sealed type battery is a nickel-metal hydride battery in which
oxidation-reduction reaction of hydrogen ion is used and a hydrogen
alloy is used as anode material.
57. A recovering apparatus according to claim 32, wherein the
sealed type battery is a nickel-cadmium battery.
58. A recovering apparatus according to claim 32, wherein the
sealed type battery is a lead-acid battery.
59. A recovering apparatus according to claim 55 which further
includes a means for reacting a reacting agent with an active
lithium contained in the lithium battery to decrease the reactivity
of said active lithium after the lithium battery is opened.
60. A recovering apparatus according to claim 59, wherein the
reacting agent comprises one or more materials selected from the
group consisting of water, alcohols, acids, and carbon dioxide.
61. A recovering apparatus according to claim 32 which further
comprises a means for conducting washing with the use of an organic
solvent after the sealed type battery is opened.
62. A recovering apparatus according to claim 61, wherein the
organic solvent is an organic solvent incapable producing an
azeotrope with water.
63. A recovering apparatus according to claim 61 or 62 which
further comprises a means for recovering the constituent battery
components after washing the opened battery with the use of the
organic solvent.
64. A recovering apparatus according to claim 32 which further
comprising a means for sorting the sealed type battery depending on
the shape or the type prior to cooling said sealed type
battery.
65. A recovering apparatus according to claim 32 which further
comprises a means for discharging the electric residual capacity of
the sealed type battery prior to cooling said battery.
66. A recovering apparatus according to claim 65, wherein the
discharging means includes a means recovering an energy
discharged.
67. A recovering apparatus according to claim 50 which further
comprises a means for recovering the incombustible gas of the
opening atmosphere and purifying the incombustible gas recovered to
recycle.
68. A recovering apparatus according to claim 44 which further
comprises a means for recovering the gas used in cooling the sealed
type battery and purifying the gas recovered to recycle.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a process and apparatus for
recovering the constituent components of a sealed type battery.
More particularly, the present invention relates to a process and
apparatus for safely and efficiently opening a sealed type battery
to recover the constituent components thereof.
[0003] 2. Related Background Art
[0004] In recent years, global warming from the so-called
greenhouse effect has been predicted due to increased level of
atmospheric CO.sub.2. To prevent this warming phenomenon from
further developing, there is a tendency to prohibit the
construction of new steam-power generation plants which exhaust a
large quantity of CO.sub.2.
[0005] Under these circumstances, proposals have been made to
institute load leveling in order to effectively utilize power. Load
leveling involves the installation of rechargeable batteries at
general locations to serve a storage for surplus power unused in
the night, known as dump power. The power thus stored is available
in the day time when the power demand is increased, leveling the
load requirements in terms of power generation.
[0006] Separately, there is an increased societal demand for
developing a high performance rechargeable battery with a high
energy density for an electric vehicle which would not exhaust air
polluting substances. There is further increased societal demand
for developing a miniature, lightweight, high performance
rechargeable battery usable as a power source for potable
instruments such as small personal computers, word processors,
video cameras, and pocket telephones.
[0007] For the batteries including rechargeable batteries for such
uses as above mentioned, there have been developed various storage
batteries including rechargeable batteries having an enclosed (or
sealed) configuration. Specific examples of such storage battery
are lead-acid battery, nickel-cadmium battery, nickel-metal hydide
battery having a high energy density, nickel-zinc battery,
rechargeable lithium battery and like others. In order for these
storage batteries to have a long battery lifetime or/and to be
ensured in terms of safety, there is usually employed a sealing
manner with the use of a battery housing. In addition, in order to
ensure further safety, these batteries are mostly provided with a
safety vent. This safety vent serves to ensure the safety when the
inside pressure of the battery housing is incidentally increased,
by communicating the inside of the battery housing to the
atmosphere outside the battery housing to thereby reduce the
increased inside pressure of the battery housing.
[0008] Now, the nickel-metal hydide battery is a rechargeable
battery in which electrochemical oxidation-reduction reaction of
hydrogen ion is used. The nickel-metal hydride battery typically
comprises an anode comprising an anode active material layer
comprised of a hydrogen storage (absorbing) alloy, a cathode
comprising a cathode active material layer comprised of nickel
hydroxide (specifically, nickelous hydroxide), and an electrolyte
solution. In this battery, when charging is operated, the hydrogen
ion of the electrolyte solution at the side of the anode is reduced
into hydrogen, followed by entering into the anode active material
layer of the anode where the hydrogen is retained therein, and when
discharging is operated, the hydrogen retained in the anode active
material layer is oxidized into hydrogen ion, followed by
incorporating into the electrolyte solution. For the cathode active
material layer of the cathode, the constituent nickel oxyhydroxide
is oxidized into a nickel oxide when charging is operated, and when
discharging is operated, the nickel oxyhydroxide is reduced into
the original nickel hydroxide. For the nickel-metal hydride
battery, in order for the hydrogen storage alloy of the anode to
efficiently retain hydrogen upon operating the charging and also in
order to attain a high battery capacity, the components of the
battery are usually sealed in a battery housing.
[0009] There are known various lithium batteries in which
electrochemical oxidation-reduction reaction of lithium ion is
used. In these lithium batteries, because lithium is readily
reacted with moisture in the atmosphere to cause a decrease in the
battery capacity, there are used an electrolyte solution in which a
nonaqueous organic or inorganic solvent which is substantially free
of moisture is used, and a battery housing capable of sufficiently
sealing their components. And the fabrication of these batteries is
conducted in an atmosphere which is sufficiently free of
moisture.
[0010] Specific examples of these lithium batteries, there can be
illustrated commercially available primary lithium batteries,
commercially available so-called lithium ion batteries, and
rechargeable lithium metal batteries (which have been put into the
research or which are under development). In the primary lithium
battery and rechargeable lithium metal batteries, their anodes have
an anode active material layer comprising a lithium metal.
[0011] In the lithium ion battery, as the anode active material
layer, there is used a carbonous material such as graphite capable
of intercalating lithium ion into the network planes of the
carbonous material when charging is operated, and as the cathode,
there is used a transition metal compound capable of intercalating
lithium ion into the transition metal compound when discharging is
operated.
[0012] Incidentally, the foregoing storage batteries including
rechargeable batteries enclosed by such battery housing as above
described have been currently using in various potable instruments.
For these sealed type batteries, to recover them and to recycle
their components will be essential not only in terms of development
of new potable instruments but also in viewpoints that they are
expected to be further developed in the future so that they can be
used in electric vehicles, load conditioners, power storage, or the
like, and also in a viewpoint that the consumption of the batteries
is expected to greatly increase in the future.
[0013] However, in order to recover the components of these sealed
type batteries, it is necessary to firstly open their battery
housings. In this case, problems are liable to entail in that upon
the opening, the cathode is often contacted with the anode to cause
internal shorts between the two electrodes, where the residual
electric capacity is suddenly consumed within a short period of
time to cause heat generation, resulting in deteriorating the
battery components such that they cannot be recycled. Because of
this, there cannot be attained a desirable recovery for the battery
components.
[0014] In this respect, for the sealed type batteries, there is an
increased demand for developing a recovering process including a
opening process which enables to efficiently recover their
components without being damaged or deteriorated even in the case
where their cathode and anode are contacted with each other upon
the opening.
SUMMARY OF THE INVENTION
[0015] The present invention has been accomplished in view of the
foregoing situation in the prior art.
[0016] An object of the present invention is to provide a
recovering process which enables to safely and efficiently recover
the components of a sealed type battery without the components
being damaged or deteriorated.
[0017] Another object of the present invention is to provide a
recovering apparatus which enables to safely and efficiently
recover the components of a sealed type battery without the
components being damaged or deteriorated.
[0018] A first aspect of the present invention lies in a recovering
process for recovering the components of a sealed type battery
sealed, comprising at least a step of decreasing the ionic
conductivity between the cathode and anode and a step of opening
the battery housing.
[0019] A second aspect of the present invention lies in a
recovering apparatus for recovering the components of a sealed type
battery, comprising at least a means for decreasing the ionic
conductivity between the cathode and anode and a means for opening
the battery housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a schematic flow diagram illustrating an example
of the recovering process for recovering the components of an
sealed type battery according to the present invention.
[0021] FIG. 2 is a schematic flow diagram illustrating another
example of the recovering process for recovering the components of
a sealed type battery according to the present invention.
[0022] FIG. 3 is a schematic diagram illustrating the constitution
of an example of an apparatus suitable for extracting an
electrolyte solution or a solvent thereof present in a sealed type
battery to decrease the ionic conductivity between the cathode and
anode in the sealed type battery prior to opening the sealed type
battery, which is used as a part of the recovering apparatus
according to the present invention.
[0023] FIG. 4 is a schematic diagram illustrating the constitution
of another example of an apparatus for extracting an electrolyte
solution or a solvent thereof present in a sealed type battery to
decrease the ionic conductivity between the cathode and anode in
the sealed type battery prior to opening the enclosed battery,
which is used as a part of the recovering apparatus according to
the present invention.
[0024] FIG. 5 is a schematic conceptual view illustrating an
apparatus portion as a principal portion of the recovering
apparatus according to the present invention, comprising a cooling
means and an unsealing (opening) means.
[0025] FIG. 6 is a schematic diagram of an example of a cooling
means used in the recovering apparatus according to the present
invention.
[0026] FIG. 7 is a schematic cross-sectional view illustrating an
example of a sealed type battery whose components are recovered in
the present invention.
[0027] FIG. 8 is a schematic cross-sectional view illustrating an
example of a coin-like shaped battery.
[0028] FIG. 9 is a schematic cross-sectional view illustrating an
example of a spiral-wound cylindrical battery.
[0029] FIG. 10 is a schematic perspective view illustrating an
example of a prismatic battery.
DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS
[0030] As previously described, the present invention includes a
recovering process for recovering the components of a sealed type
battery sealed, comprising at least a step of decreasing the ionic
conductivity between the cathode and anode and a step of opening
the battery housing; and a recovering apparatus for recovering the
components of a sealed type battery, comprising at least a means
for decreasing the ionic conductivity between the cathode and anode
and a means for opening the battery housing.
[0031] A principal feature of the recovering process is that prior
to opening the sealed type battery, to decrease the ionic
conductivity between the cathode and anode is conducted. Similarly,
a principal feature of the recovering apparatus according to the
present invention is to have a specific means for decreasing the
ionic conductivity between the cathode and anode prior to opening
the enclosed type battery.
[0032] In the present invention, by extracting the electrolyte
solution or the solvent of the electrolyte solution outside the
sealed type battery to decrease the ionic conductivity between the
cathode and anode prior to opening the battery housing of the
sealed type battery, even in the case where internal shorts should
be occurred between the cathode and anode when the battery housing
is opened or the battery components are taken out from the inside
of the battery housing as will be described later, the occurrence
of sudden energy release and combustion due to the internal shorts
is effectively prevented. As a result, it is possible to safely
recover the battery components without being deteriorated or
destroyed. By this, there can be realized safe recovery of the
components of the sealed type battery at a high recovery rate.
[0033] The recovering process and apparatus according to the
present invention are effective in recovering the components of any
sealed type batteries including sealed type primary and secondary
(rechargeable) batteries, notwithstanding the kind of a battery
enclosed therein.
[0034] Specific examples of such sealed type battery for which the
recovering process and the recovering apparatus according to the
present invention are particularly effective in recovering the
battery components are lithium batteries including lithium ion
rechargeable batteries (in which an anode comprising a carbonous
material capable of intercalating lithium ion is used) in which
electrochemical oxidation-reduction reaction of lithium ion is
used; nickel-metal hydride rechargeable batteries having an anode
comprising a hydrogen storage alloy and in which electrochemical
oxidation-reduction reaction of hydrogen ion is used; and
nickel-cadmium batteries.
[0035] Herein, for the lithium batteries, a variety of enclosed
type primary lithium batteries having an anode comprising a lithium
metal have been frequently using in potable instruments such as
cameras, wristwatches and the like. And the consumption of these
primary lithium batteries are expected to further increase in the
future. In addition, the consumption of rechargeable lithium
batteries is expected to increase in the future. Under this
circumstance, the waste disposal of these lithium batteries will be
possibly a serious problem in the future as well as in the case of
other batteries. In this respect, it is an urgent necessity of
recovering and recycling their components such as anodes, cathodes,
electrolytes, separators, and housings.
[0036] Now, in order to separately recover the components of an
used sealed type lithium battery, the battery housing is required
to be opened while preventing external moisture invasion, which
will be a cause of damaging or deteriorating the battery
characteristics.
[0037] As a most simple manner for unsealing the battery housing of
an enclosed type battery, there is considered a mechanically
cutting manner. However, when this manner is employed particularly
in the case of an enclosed type lithium battery, problems are
liable to entail in that as the energy per unit volume and unit
weight is extremely high and a combustible material such as organic
solvent is contained, a spark is generated or internal shorts are
occurred between the anode and cathode upon mechanically cutting
the battery housing, where the components are damaged or
deteriorated. Besides, other problems are liable to entail such
that will be described in the following. When the battery
components situated inside the battery housing are taken out after
the battery housing has been unsealed, as the anode and cathode are
closed to each other, they tend to readily suffer from internal
shorts where the internal shorts should be occurred between them,
the residual battery energy is released at a stroke to cause sudden
heat generation.
[0038] Therefore, particularly for a sealed type lithium battery,
there is demand for developing a desirable recovering process and a
desirable recovering apparatus capable of recovering the battery
components without being damaged or deteriorated for dealing with
an increase in the consumption thereof.
[0039] The present invention desirably meets this demand.
[0040] In the recovering process for recovering the components of a
sealed type battery which comprises an electrolyte solution as the
electrolyte, the step of decreasing the ionic conductivity between
the cathode and anode is desired to be conducted by a manner of
extracting the electrolyte solution or the solvent thereof present
within the battery housing outside the battery housing. In the case
where the enclosed battery provided with a safety vent, to extract
the electrolyte solution or the solvent thereof outside the battery
housing is desired to be conducted while taking advantage of the
safety vent in view of working efficiency, for instance, in a
manner wherein through the safety vent, the pressure of the
atmosphere outside the battery housing is decreased to increase the
inside pressure of the battery housing whereby causing a
differential pressure between the outside and the inside of the
battery housing, and by this, the safety vent is actuated to
extract the electrolyte solution or the solvent thereof outside the
battery housing. The electrolyte solution or the solvent thereof
thus extracted outside the battery housing can be recycled.
[0041] In the recovering process for recovering the components of a
sealed type battery, the step of decreasing the ionic conductivity
between the cathode and anode is desired to be conducted at least
through a manner of cooling the enclosed type battery. In the case
where this manner is employed, when a solvent is used in the
electrolyte solution of the sealed type battery, it is desired to
cool the sealed type battery to a temperature which is lower than
the freezing point of the solvent. In the case where a solid
polymer electrolyte solidified by using a polymer is used in the
sealed type battery, it is desired to cool the sealed type battery
to a temperature which is lower than the glass transition
temperature of the constituent polymer of the solid polymer
electrolyte.
[0042] The above manner of cooling the sealed battery can be
conducted by a cooling manner of cooling an object using an
incombustible compressed gas comprising one or more gases selected
from the group consisting of N.sub.2 gas, Ar gas, He gas, CO.sub.2
gas and fluorocarbon gas.
[0043] Besides this, it is possible for the above manner of cooling
the sealed type battery to be conducted by a manner of cooling the
sealed type battery by immersing it in a cooling agent or a
liquefied gas. The cooling agent can include, for example, a
mixture comprising dryice and methanol and a mixture comprising
dryice and ethanol. The liquefied gas can include, for example,
liquid nitrogen and the like.
[0044] Alternatively, it is possible for the above manner of
cooling the sealed type battery to be conducted by a manner of
immersing the sealed type battery in water, followed by freezing
the enclosed type battery together with the water. In this case,
the sealed type battery is desired to be opened in a state in that
the sealed type battery is sealed in the ice.
[0045] In the recovering process for recovering the components of a
sealed type battery, it is desired for the step of opening the
battery housing after the ionic conductivity between the cathode
and anode has been decreased to be conducted in an incombustible
atmosphere. In this case, there are provided advantages in that the
battery components are prevented from being oxidized or combusted
and they can be safely recovered while desirably preventing them
from being damaged or deteriorated at a high recovery. The above
incombustible atmosphere may be an atmosphere composed of one or
more gases selected from the group consisting of N.sub.2 gas, Ar
gas, He gas, CO.sub.2 gas, fluorocarbon gas, and steam. In the case
where the foregoing cooling manner using the incombustible
compressed gas is employed in the step of decreasing the ionic
conductivity between the cathode and anode, the gas used to
constitute the atmosphere for opening the battery housing is
desired to the same as the gas used as the compressed gas.
[0046] As the manner of opening the battery housing, there can be
illustrated a cutting process using a high pressure water, a
cutting process using a energy beam, a mechanically cutting
process, and a cutting process by way of spraying a high pressure
water containing an abrasive mixed therein to an object through a
jet nozzle.
[0047] In the present invention, by subjecting the battery to
discharging prior to opening the housing of the sealed type
battery, preferably at a stage before decreasing the ionic
conductivity between the cathode and anode, to open the sealed type
battery can be more safely conducted. In this case, the chemical
composition of the constituent material for each of the cathode and
anode active material layers becomes uniform without depending upon
the residual battery capacity before the discharging, where the
cathode material and the anode material each having a satisfactory
uniformity in terms of the chemical composition can be recovered.
Further in this case, by means of the discharging, it is possible
to withdraw the energy remained in the enclosed battery.
[0048] Further in the present invention, by sorting the sealed
batteries depending on the shape or the type before their housings
are unsealed, their components can be efficiently recovered.
[0049] As previously described, the recovering apparatus according
to the present invention for recovering the components of a sealed
type battery sealed by a battery housing, comprises at least a
means for decreasing the ionic conductivity between the cathode and
anode and a means for opening the battery housing.
[0050] The means for decreasing the ionic conductivity between the
cathode and anode is desired to comprise at least a means for
extracting the electrolyte solution or the solvent thereof present
inside the battery housing outside the battery housing. In the case
where the sealed type battery is provided with a safety vent, this
means is desired to have a function of actuating the safety vent,
for instance, by decreasing the pressure of the atmosphere outside
battery housing to increase the inside pressure of the battery
housing across the safety vent whereby causing a differential
pressure between the outside and the inside of the battery housing
and a means for extracting the electrolyte solution or the solvent
thereof present inside the battery housing outside the battery
housing through the safety vent. The means for extracting the
electrolyte solution or the solvent thereof present inside the
battery housing outside the battery housing is desired to comprise
a vessel provided with at least an exhaust means. It is desired for
the vessel in this case to be provided with a member which can be
close-contacted with or joined to the battery housing's exterior
wall face including a portion of the battery capping in the
neighborhood of the safety vent and an opening (or a passage) for
transferring the electrolyte solution or the solvent thereof (which
is extracted from the battery) into the vessel.
[0051] In the above described vessel, a port capable of introducing
air, nitrogen gas (N.sub.2) or inert gas thereinto may be provided
through a valve.
[0052] In the recovering apparatus according to the present
invention, for instance, by establishing a closed or sealed space
by a part of the battery housing's exterior face including the
battery capping or the entire thereof (including the portion
through which the electrolyte solution or the solvent thereof is
extracted) and the above described vessel and decreasing the inner
pressure of the sealed space than the inner pressure of the
enclosed battery while maintaining the safety vent portion in the
sealed space, the electrolyte solution or the solvent present
inside the battery housing can be desirably recovered into the
vessel through the safety vent.
[0053] In the recovering apparatus according to the present
invention, the above closed (sealed) space is desired to be
established by connecting the above vessel provided with the
exhaust means to a region including a portion (e.g., the safety
vent) through which the electrolyte solution or the solvent thereof
present inside the battery housing is extracted after the inner
pressure of the above vessel has been decreased than the
atmospheric pressure by means of the exhaust means provided at the
vessel.
[0054] In the recovering apparatus according to the present
invention, it is possible that the above closed space is first
established by the above and thereafter, the inner pressure of the
sealed space is lowered than the inner pressure of the sealed
battery by means of the above exhaust means provided at the
vessel.
[0055] In the recovering apparatus according to the present
invention, the foregoing means for decreasing the ionic
conductivity between the cathode and anode is desired to comprise a
cooling means for cooling the sealed type battery.
[0056] To cool the sealed type battery by means of the cooling
means is desired to be conducted by using an incombustible
compressed gas comprising one or more gases selected from the group
consisting of N.sub.2 gas, Ar gas, He gas, CO.sub.2 gas and
fluorocarbon gas in the cooling means.
[0057] Alternatively, to cool the enclosed battery by means of the
cooling means may be conducted by using a cooling agent or a
liquefied gas in the cooling means. The cooling agent can include,
for example, a mixture comprising dryice and methanol and a mixture
comprising dryice and ethanol. The liquefied gas can include, for
example, liquid nitrogen and the like.
[0058] Further, it is possible that the sealed type battery is
immersed in water, followed by freezing the sealed type battery
together with the water. In this case, the sealed type battery is
desired to be opened in a state in that the enclosed battery is
sealed in the ice.
[0059] In the recovering apparatus according to the present
invention, as the means for unsealing the battery housing, there
can be illustrated a cutting means using a high pressure water, a
cutting means using a energy beam, a mechanically cutting means,
and a cutting means using a high pressure water containing an
abrasive mixed therein.
[0060] To open the battery housing by any of these cutting means is
desired to be conducted in an incombustible atmosphere. The
incombustible atmosphere may be an atmosphere composed of one or
more gases selected from the group consisting of N.sub.2 gas, Ar
gas, He gas, CO.sub.2 gas, fluorocarbon gas, and steam.
[0061] In the following, preferred embodiments of the present
invention will be described while referring to the drawings.
[0062] FIG. 1 is a schematic flow diagram illustrating an example
of the recovering process for recovering the components of a sealed
type battery according to the present invention.
[0063] Description will be made of an embodiment of the recovering
process according to the present invention with reference to FIG.
1.
[0064] In order to efficiently recover the components of a sealed
type battery, used sealed type batteries (FIG. 1(a-1)) collected
for recovering their components are first sorted depending on the
shape or the type (see, FIG. 1(a-2)).
[0065] Then, the sealed type battery thus sorted is subjected to
decrease the ionic conductivity between the anode and cathode (see,
FIG. 1(a-3)). In this case, to decrease the ionic conductivity
between the cathode and anode may be conducted by the foregoing
manner of extracting the electrolyte solution or the solvent
thereof present between the cathode and anode (in the case of using
the electrolyte solution as the electrolyte in the battery) outside
the battery housing through the safety bent or the like annexed to
the battery housing. Alternatively, it may be conducted by the
foregoing manner of cooling the battery to decrease the ionic
conductivity between the cathode and anode.
[0066] Thereafter, the battery housing is opened (see, FIG.
1(a-4)), followed by taking out a body comprising the battery
components present inside the battery housing (see, FIG.
1(a-5)).
[0067] The body thus taken out is washed (see, FIG. 1(a-6). Then,
the body is dissociated (separated) into individual battery
components and the battery components thus dissociated are
recovered (see, FIG. 1(a-7)).
[0068] FIG. 2 is a schematic flow diagram illustrating another
example of the recovering process for recovering the components of
a sealed type battery according to the present invention.
[0069] Description will be made of another embodiment of the
recovering process according to the present invention with
reference to FIG. 2.
[0070] In order to efficiently recover the components of each used
sealed type battery, used sealed type batteries (FIG. 2(b-1))
collected for recovering their components are first sorted
depending on the shape or the type (see, FIG. 2(b-2)).
[0071] Then, the sealed type battery thus sorted is cooled to
decrease the ionic conductivity between the anode and cathode
whereby increasing the internal resistance (see, FIG. 2(b-3)).
[0072] Thereafter, the battery housing of the sealed type battery
thus cooled in the above step is opened in an incombustible
atmosphere (see, FIG. 2(b-4)).
[0073] Then, in the case where the battery in the sealed type
battery is based on a lithium battery, an appropriate reacting
agent is reacted with the active lithium present inside the battery
housing to decrease the reactivity of the lithium (see, FIG.
2(b-5)).
[0074] Successively, a body comprising the battery components
present inside the battery housing is taken out (see, FIG.
2(b-6)).
[0075] In the case where the electrolyte is in the liquid state,
the body (comprising the battery components) thus taken out is
washed with an appropriate organic solvent (see, FIG. 2(b-7)).
[0076] Then, the body thus washed is dissociated into individual
battery components and the battery components thus dissociated are
recovered (see, FIG. 2(b-8)).
[0077] If necessary, the residual electric capacity in the used
sealed battery may be discharged after sorting the battery, where
the steps of opening the battery housing, dissociating the battery
into individual components and recovering the components may be
conducted more safely. Specific examples of the manner for doing
this, there can be mentioned a manner wherein the anode and cathode
terminals of the battery are electrically connected to a capacitor
to conduct discharging, and a manner wherein charging is conducted
by connecting a resistance between the anode and cathode terminals
of the battery. In any case, the charging is conducted until the
electric capacity of the battery decreases suddenly.
[0078] In the following, with reference to the drawings,
description will be made of the foregoing manner of extracting the
electrolyte or the solvent thereof present inside the battery
housing as a measure for decreasing the ionic conductivity between
the cathode and anode in a sealed type battery.
[0079] FIG. 3 is a schematic diagram illustrating the constitution
of an example of an apparatus suitable for extracting an
electrolyte solution or a solvent thereof present in a sealed type
battery to decrease the ionic conductivity between the cathode and
anode in the sealed type battery prior to opening the housing of
the sealed type battery, which is used as a part of the recovering
apparatus according to the present invention.
[0080] FIG. 4 is a schematic diagram illustrating the constitution
of another example of an apparatus suitable for extracting an
electrolyte solution or a solvent thereof present in a sealed type
battery to decrease the ionic conductivity between the cathode and
anode in the sealed type battery prior to opening the housing of
the sealed type battery, which is used as a part of the recovering
apparatus according to the present invention.
[0081] Each of the apparatus shown in FIGS. 3 and 4 is
corresponding to an example of a system used in the foregoing
recovering apparatus, for extracting the electrolyte solution or
the solvent thereof through the safety vent or the like to decrease
the ionic conductivity between the cathode and anode in the sealed
type battery prior to opening the housing of the sealed type
battery while recovering the electrolyte solution or the solvent
thereof.
[0082] In the case of the apparatus shown in FIG. 3, the apparatus
is contacted through its specific contact means with a sealed type
battery having a safety vent such that the apparatus is tightly
contacted with a portion of the battery housing's exterior wall of
the sealed type battery in the neighborhood of the safety vent and
the neighborhood of the safety vent is locally depressurized to
cause a differential pressure between the outside and the inside of
the battery housing. By this, the safety vent is actuated to
communicate the outside and the inside of the battery housing
whereby the electrolyte or the solvent thereof present inside the
battery housing is extracted.
[0083] In the case of the apparatus shown in FIG. 4, the apparatus
is provided with a specific vessel capable of being vacuumed. An
enclosed type battery is placed in the vessel, and the inside
(containing the enclosed type battery) of the vessel is
depressurized to relatively increase the internal pressure of the
sealed type battery whereby causing a differential pressure between
the outside and the inside of the battery housing. By this, the
safety vent is actuated to communicate the outside and the inside
of the battery housing whereby the electrolyte or the solvent
thereof present inside the battery housing is extracted.
[0084] Description will be made of the apparatus shown in FIG. 3
and its operation.
[0085] In FIG. 3, reference numeral 100 indicates an enclosed type
battery sealed in a battery housing 101. Reference numeral 102
indicates a safety bent annexed to the enclosed type battery.
[0086] Reference numeral 103 indicates an extraction pipe for
extracting an electrolyte solution or a solvent of said electrolyte
solution from the battery 100. The extraction pipe 103 is provided
with a switching valve 108 serving as an extraction valve for an
electrolyte or a solvent of said electrolyte solution, and it is
also provided with a gas supply pipe for introducing air, nitrogen
gas or inert gas into the apparatus. The gas supply pipe is
provided with a leak valve 113.
[0087] Reference numeral 104 indicates a storage tank for storing
the electrolyte solution or the solvent thereof extracted from the
enclosed type battery 100 through the extraction pipe 103.
[0088] Reference numeral 105 indicates a vacuuming means comprising
a vacuum pump or the like which is connected to the storage tank
104 through an exhaust pipe 107 provided with an exhaust valve 109.
Reference numeral 106 indicates an O-ring for attaining a tight
contact. Reference numeral 110 indicates a drain valve provided at
the storage tank 104.
[0089] Particularly, in the apparatus shown in FIG. 3, the
extraction pipe 103 has a first opening portion provided with the
O-ring 106, a second opening portion open into the storage tank
104, and a gas introduction opening portion through which air,
nitrogen gas or incombustible gas supplied through the gas supply
pipe provided with the leak valve 113 can be introduced into the
inside of the apparatus. Said first opening portion is situated at
an exterior wall portion of the battery housing 101, said exterior
wall portion including the neighborhood of the safety vent 102 of
the sealed battery 100, and said neighborhood including a portion
of a battery capping or lid (not shown) of the battery 100.
Particularly, the first opening portion is tightly contacted with
or joined to said exterior wall portion of the battery housing 101
through the O-ring 106 as shown in FIG. 3. And as above described,
the second opening portion of the extraction pipe 103 is open into
the storage tank 104. By this, the battery 100 is communicated with
the inside of the storage tank 104 through the extraction pipe
103.
[0090] In the above system, there is established a space comprising
the above described battery housing's exterior wall portion
(including the safety vent 102 of the battery 100), the inside of
the extraction pipe 103 and the inside of the storage tank 104.
Herein, the battery 100 is arranged such that its portion having
the safety vent 102 downwardly faces as shown in FIG. 3. By means
of the vacuuming means 105 connected through the exhaust pipe 107
provided with the exhaust valve 109 to the storage tank 104, the
inside of the system is depressurized to make the above space have
an internal pressure which is lower than that of the battery 100.
By this, the safety vent 102 is actuated (opened in other words),
where the electrolyte solution or the solvent thereof contained in
the battery 100 is extracted into the extraction pipe 103, followed
by flowing into the storage tank 104. As a result, there is
provided a situation in that no electrolyte solution is present
between the cathode and anode (not shown) in the battery 100 and
the ionic conductivity between the two electrodes is decreased.
[0091] In the above operation, if necessary, it is possible that
the leak valve 113 of the gas supply pipe is actuated to introduce
air, nitrogen gas or inert gas into the system.
[0092] For the electrolyte solution or the solvent thereof
extracted into the storage tank 104, a predetermined amount thereof
is periodically drained by actuating the drain valve 110 to the
outside, followed by recovering. The electrolyte solution or the
solvent thereof thus recovered may be recycled.
[0093] In the following, description will be made of the apparatus
shown in FIG. 4 and its operation.
[0094] The apparatus shown in FIG. 4 comprises a battery container
111 provided with a extraction pipe 103 which is extended into a
storage tank 104. The battery container 111 serves to house a
sealed type battery 100 having a safety vent 102 to be treated. The
extraction pipe 103 serves to extract an electrolyte solution or a
solvent of said electrolyte solution contained in the sealed type
battery 100. The extraction pipe 103 has an opening at one end
thereof which is open into the battery container 111 and another
opening at the other end thereof which is open into the storage
tank 104. The extraction pipe 103 is provided with a switching
valve 108 serving as an extraction valve for the electrolyte
solution or the solvent thereof.
[0095] The storage tank 104 serves to store the electrolyte
solution or the solvent thereof which is extracted from the battery
100 through the extraction pipe 103. The inside of the storage tank
104 is connected to a vacuuming means 105 comprising a vacuum pump
or the like through an exhaust pipe 107 provided with an exhaust
valve 109.
[0096] The battery container is provided with a gas supply pipe
provided with a leak valve 113, which serves to introduce air,
nitrogen gas or inert gas into the battery container 111. Reference
numeral 112 indicates a capping for the battery container 111. The
capping 112 is tightly capped to the battery container 111 by means
of an O-ring 106.
[0097] In the above system, there is established a space comprising
the capping 112, the inside of the battery container 111, the
entire of the battery housing's exterior wall including the safety
vent 102, the inside of the extraction pipe 103 and the inside of
the storage tank 104. Herein, the battery 100 is arranged such that
its portion having the safety vent 102 downwardly faces as shown in
FIG. 4. By means of the vacuuming means 105, the inside of the
system (from the extraction pipe 103 through the storage tank) is
depressurized to make the above space have an internal pressure
which is lower than that of the battery 100. By this, the safety
vent 102 is actuated (opened in other words), where the electrolyte
solution or the solvent thereof contained in the battery 100 is
extracted into the extraction pipe 103, followed by flowing into
the storage tank 104. As a result, there is provided a situation in
that no electrolyte solution is present between the cathode and
anode (not shown) in the battery 100 and the ionic conductivity
between the two electrodes is decreased.
[0098] In the above operation, if necessary, it is possible that
the leak valve 113 of the gas supply pipe is actuated to introduce
air, nitrogen gas or inert gas into the system.
[0099] For the electrolyte solution or the solvent thereof
extracted into the storage tank 104, a predetermined amount thereof
is periodically drained by opening the drain valve 110 to the
outside, followed by recovering. The electrolyte solution or the
solvent thereof thus recovered may be recycled.
[0100] For the sealed type battery from which the electrolyte
solution or the solvent thereof has been extracted in the system
shown in FIG. 3 or 4 as above described, its housing is opened by
an appropriate unsealing manner in a state in that the ionic
conductivity between the cathode and anode has been decreased, and
the battery components are recovered.
[0101] In the following, description will be made of an embodiment
of the step of increasing the internal resistance of a sealed type
battery by cooling the battery and an embodiment of the step of
opening the housing of said cooled battery in the process for
recovering the components of a sealed type battery by decreasing
the ionic conductivity between the cathode and anode in the sealed
type battery, while referring to an apparatus shown in FIG. having
a system capable of conducting these steps.
[0102] FIG. 5 is a schematic conceptional view illustrating an
example of an apparatus for cooling a sealed type battery and
opening its battery housing as a part of the recovering apparatus
according to the present invention for recovering the components of
a sealed type battery.
[0103] In the apparatus shown in FIG. 5, there is shown a case
wherein a cooling apparatus capable of cooling a sealed type
battery by using a compressed gas of an incombustible gas is used,
and the same incombustible gas is used as an atmosphere under which
to unseal the battery housing is conducted. The apparatus shown in
FIG. 5 is provided with a means for recovering the gas having used
for cooling the enclosed type battery, purifying the recovered gas
and recycling the purified gas. In the apparatus shown in FIG. 5,
in order to open the battery housing, a high pressure water or
energy beam is used.
[0104] The apparatus shown in FIG. 5 and its operation will be
detailed.
[0105] In FIG. 5, reference numeral 200 indicates an enclosed type
battery, reference numeral 201 a cooling apparatus (a low
temperature gas-blowing apparatus), reference numeral 202 a low
temperature gas, reference numeral 203 an incombustible atmosphere,
reference numeral 204 an unsealing apparatus for a battery housing,
reference numeral 205 a high pressure water or energy beam,
reference numeral 206 a partition wall, reference numeral 207 a
fixing table for an enclosed type battery, reference numeral 208 a
transportation mechanism for an enclosed type battery, reference
numeral 209 a gas feed pipe for a compressed gas, reference numeral
210 a compressor, reference numeral 211 a removing device for
removing impurities such as water, reference numeral 212 an
incombustible gas-recovering device, reference numeral 213 a gas
pipe for recovering an incombustible gas, reference numeral 214 a
generation device for generating a high pressure water or energy
beam, and reference numeral 215 a transfer pipe for a high pressure
water or a transmission pipe for an energy beam.
[0106] In the apparatus shown in FIG. 5, a used, sealed type
battery 200 is fixed onto the fixing table 207 arranged on
transportation mechanism 208 provided in the chamber demarcated by
the partition wall 206, followed by sequentially transporting to
the cooling step zone having the cooling apparatus 201 then to the
unsealing step zone having the unsealing apparatus 204. The chamber
space demarcated by the partition wall 206 including the zone of
the cooling apparatus 201 and the zone of the unsealing apparatus
is filled with an incombustible gas (the incombustible atmosphere
203).
[0107] At the cooling apparatus 201, a low temperature gas 202
comprising a cooled incombustible gas is supplied to the enclosed
type battery 200 to cool the electrolyte contained in the enclosed
battery whereby decrease its ionic conductivity. As the low
temperature gas 202 used herein, it is desired that the
incombustible gas inside the partition wall 206 is recycled to use.
Particularly in this respect, said incombustible gas is recovered
by the incombustible gas-recovering device 212 through the gas
conduit 213 connected to the chamber demarcated by the partition
wall 206, purified by the impurities-removing device 211,
compressed by the compressor 210, supplied to the cooling apparatus
201, followed by supplying to the enclosed type battery 200 as the
low temperature gas 202 (the compressed gas).
[0108] In the above cooling step for cooling the enclosed type
battery, it is possible to cool the sealed type battery, for
example, by using a cooling agent or liquefied gas. Alternatively,
to cool the sealed type battery may be conducted by a manner
wherein the sealed type battery is immersed in water, followed by
freezing the water together with the battery such that the battery
is sealed in the ice.
[0109] Then, at the unsealing apparatus 204, for example, a high
pressure water or energy beam 205 is effected to the sealed type
battery 200 having been cooled in the above cooling step to open
the battery housing. The high pressure water or energy beam used
herein is produced by the generation device 214, followed by
supplying to the unsealing apparatus 204 through the transfer pipe
or transmission pipe 215.
[0110] In the following, description will be made of detailed
conditions in the cooling step for cooling an enclosed type
battery, said cooling step including the foregoing cooling step
using the apparatus shown in FIG. 5.
Cooling Temperature
[0111] Description will be made of the cooling temperature to which
an enclosed type battery is cooled in order to decrease the ionic
conductivity of the electrolyte.
[0112] For instance, when the sealed type battery is a sealed type
lithium battery in which an electrolyte solution comprising an
electrolyte and an organic solvent is used as the electrolyte, in
order to decrease the ionic conductivity of the electrolyte, the
lithium battery is desired to be cooled to a temperature which is
lower than the freesing temperature of the organic solvent of the
electrolyte solution.
[0113] When the electrolyte of the lithium battery comprises a
polymer solid electrolyte solidified by using a polymer, in order
to decrease the ionic conductivity of the electrolyte, the lithium
battery is desired to be cooled to a temperature which is lower
than the glass transition temperature of the polymer of the polymer
solid electrolyte.
[0114] Specifically, the range of the cooling temperature is
preferably 0.degree. C. or less, more preferably -20.degree. C. or
less.
[0115] In the case where the sealed type battery is other sealed
type battery such as sealed type metal hydride battery, sealed type
nickel-cadmium battery, sealed type lead-acid battery, or the like,
the cooling temperature for these batteries is desired to be in the
above described temperature range.
Cooling Means
[0116] Description will be made of the cooling means for cooling a
sealed type batter in order to decrease the ionic conductivity of
the electrolyte.
[0117] To cool a sealed type battery in order to decrease the ionic
conductivity of the electrolyte may be conducted by a cooling
manner with the use of a compressed gas comprising an incombustible
gas (by using an appropriate cooling apparatus such as the cooling
apparatus 201 shown in FIG. 5), or other cooling manner with the
use of a liquefied gas or a cooling agent.
[0118] The cooling manner with the use of a compressed gas
comprising an incombustible gas may be conducted also by using a
cooling apparatus as shown in FIG. 6. The cooling apparatus shown
in FIG. 6 is a tube-like shaped cooling apparatus comprising a
compressed gas supply port 705 through which a compressed gas 704
is supplied, a hot gas exhaust port 708 including a pressure
regulator 706, a cooling gas outlet 702, and a vortex generator
zone 703 to generate a vortex flow 709. Reference numeral 701
indicates a direction for a cooling gas to be spouted, and
reference numeral 707 a hot gas to be exhausted.
[0119] In the cooling apparatus shown in FIG. 6, by flowing a
compressed gas 704 into the inside of the apparatus through the gas
supply port 705, a cooling gas is spouted in the direction 701
through the cooling gas outlet 702. In the case where a gas having
a temperature of about 16.degree. C. is supplied at a gas pressure
of 3 to 7 Kg/cm through the gas supply port 705, there is obtained
a cold gas having a temperature of about -10 to about -50.degree.
C. The compressed gas used in this apparatus may comprise an
incombustible gas comprising one or more gases selected from the
group consisting of N.sub.2 gas, Ar gas, He gas, CO.sub.2 gas, and
fluorocarbon gas.
[0120] By this, particularly in the case where the cooling step and
the opening step for the sealed type battery in an continuous
atmosphere (which will be described later), even when internal
shorts should be incidentally occurred between the node and cathode
upon opening the battery housing by way of a cutting manner, the
generation of a spark can be desirably prevented. Further, in the
case of an enclosed type battery having a battery housing capable
of being opened by way of disassembling without conducting cutting
operation or the like, the generation of a spark due to internal
shorts between the anode and cathode can be desirably prevented at
the time when the components including the electrodes are taken
out. Because of this, the recovery operation of the battery
components can be safely conducted.
[0121] In the case where the cooling step is conducted using a
liquefied gas, there can be employed a cooling manner wherein the
entire of an sealed type battery to be opened is directly immersed
in an appropriate liquefied gas such as liquid nitrogen, liquid
helium or the like or a cooling manner wherein a gasified low
temperature gas of a liquefied gas is sprayed onto the battery
housing of the sealed type battery to be unsealed.
[0122] In the case where the cooling step is conducted using a
cooling agent, the cooling agent can include dryice-methanol,
dryice-ethanol, and ice.
[0123] As previously described, it is possible that a sealed type
battery is immersed in water, the water is frozen together with the
battery, followed by opening the battery housing in a state in the
battery is sealed in the ice.
Battery Opening
[0124] Description will be made of particulars in the opening step
for opening the housing of a sealed type battery in which the ionic
conductivity of the electrolyte has been decreased by means of the
apparatus shown in FIG. 3 or 4 and in the opening step in the
apparatus shown in FIG. 5.
[0125] The atmosphere in which to open the housing of a sealed type
battery is conducted is desired to be comprised of an incombustible
gas comprising one or more gases selected from the group consisting
of N.sub.2 gas, Ar gas, He gas, CO.sub.2 gas, steam, and
fluorocarbon gas. In this case, even when internal shorts should be
incidentally occurred between the anode and cathode upon opening
the battery housing, the generation of a spark is desirably
prevented and in addition, the battery components are desirably
prevented from being damaged due to oxidation.
[0126] In the case where the cooling step is conducted by spraying
a low temperature gas to the sealed type battery as previously
described, by using a gas of the same kind as the low temperature
gas as the constituent of the atmosphere in which the unsealing
step is conducted, there are provided advantages such that the
operation including recovery and recycling of the gas can be
readily conducted and the running cost is reasonable.
[0127] Specific examples of the above fluorocarbon gas are
tetrafluoromethane, hexafluoroethane, perfluoropropane,
trifluoromethane, monobromotrifluoromethane,
dichlorodifluoromethane, and chlorotrifluoromethane.
Battery Unsealing Means
[0128] As previously described, to open the battery housing of a
sealed type batter may conducted an appropriate unsealing manner by
way of cutting with the use of a high pressure water or an energy
beam (for instance, the unsealing manner using the unsealing
apparatus 204 shown in FIG. 5) or a mechanically cutting
manner.
[0129] The cutting with the use of a high pressure water may be
conducted, for example, by a manner of spraying an extra-high
pressure water of preferably 1000 Kg/cm.sup.2 or more or more
preferably, 3000 Kg/cm.sup.2 or more onto the battery housing of an
enclosed type battery in a jet-like state through a nozzle. In this
case, the extra-high pressure water to be sprayed may contain an
appropriate abrasive depending upon the kind of the constituent of
the battery housing.
[0130] The above energy beam can include laser beam, electron beam
and the like.
[0131] The above mechanically cutting manner may be conducted by
using a cutting apparatus of cutting an object by rotating a
disc-like shaped blade (having a hard and sharp edge) at a high
speed or by way of shearing.
[0132] Incidentally, in the case where the sealed type battery is
cooled such that the battery is sealed in the ice as previously
described, to open the housing of the battery is desired to be
conducted while maintaining said sealed state.
[0133] For the sealed type battery in which the ionic conductivity
of the electrolyte has been decreased and whose housing has been
opened as previously described, the inside of the resultant battery
is subjected washing or the like, followed by subjecting to
classification and separation, and at a final stage, the
constituent components thereof are recovered.
Decrease of Reactivity of Active Lithium and Recovery of Lithium
Element
[0134] In the case where the sealed type battery to be subjected to
recover is a sealed type lithium battery, after the battery housing
has been opened, by decreasing the reactivity of an active lithium
contained in the lithium battery, the successive step for
recovering the battery components can be safely conducted. To
decrease the reactivity of the active lithium having a high
reactivity may be conducted by a manner of reacting an appropriate
reacting agent with the active lithium. From the reaction product
comprising the reacting agent and lithium obtained in this case,
the recovery of lithium element can be easily conducted.
[0135] Specific examples of the reacting agent are water, alcohols,
acids, carbon dioxide, and mixtures of two or more of these.
Recovery of Electrolyte Solution
[0136] In the case where the electrolyte solution of a sealed type
battery is extracted by increasing the internal pressure of the
enclosed type battery, for instance, in the manner previously
described with reference to FIGS. 3 and 4, followed by opening the
battery housing, the recovery of the electrolyte solution can be
easily conducted.
[0137] Now, to recover the electrolyte solution in the case where a
sealed type battery is cooled and the battery housing is opened may
be conducted, for example, in the following manner.
[0138] In the case of a sealed type battery in which an aqueous
electrolyte solution is used, after the battery housing is opened,
the resultant unsealed battery is subjected to washing with
deionized water, the resultant washed solution is filtrated,
followed by vaporizing water, whereby the electrolyte can be
recovered.
[0139] In the case of a sealed type battery in which an electrolyte
solution comprising an electrolyte dissolved in an organic solvent
is used, after the battery housing is unsealed, the resultant
unsealed battery is subjected to washing with an appropriate
organic solvent, followed by subjecting to fractional distillation,
whereby the electrolyte solution can be recovered. As the organic
solvent in this case, when an organic solvent incapable of forming
an azeotrope with water is used, there are provided advantages such
that a cutting manner using a high pressure water can be employed
in cutting the battery housing, and as the reacting agent in order
to decrease the reactivity of the active lithium, readily
obtainable water with a reasonable production cost can be used.
[0140] Description will be made of the above organic solvent
incapable of forming an azeotrope with water.
[0141] As above described, in the case of an enclosed type lithium,
by using an organic solvent incapable of forming an azeotrope with
water in washing an unsealed lithium battery obtained as a result
of having unsealed the sealed type lithium battery, even when
inexpensive deionized water is used as the reacting agent to
decrease the reactivity of the active lithium contained in the
lithium battery, the washing organic solvent can be readily
separated from the water by way of fractional distillation.
[0142] Specific examples of the foregoing organic solvent incapable
of forming an azeotrope with water are methanol, acetone,
1,2-propanediol, dimethyl sulfoxide, butyrolactone, ethylene
carbonate, and propylene carbonate.
[0143] In the following, description will be made of an enclosed
type battery whose constituent components are recovered according
to the present invention, while referring to the drawings.
[0144] FIG. 7 is a schematic cross-sectional view illustrating an
example of a sealed type battery whose constituent components are
recovered according to the recovering process or apparatus
according to the present invention.
[0145] The sealed type battery shown in FIG. 7 comprises an anode
301, a cathode 302 and a separator 303 including an electrolyte
which are enclosed by a battery housing 304. In the case where a
solid electrolyte is used as the electrolyte, no separator is
occasionally installed. Reference numeral 305 indicates a negative
terminal, and reference numeral 306 indicates a positive
terminal.
[0146] For the configuration of the enclosed type battery
(particularly, the sealed type rechargeable battery) whose
constituent components are recovered according to the recovering
process or apparatus according to the present invention, it may be
in the form of a flat round shape (or a coin-like shape), a
cylindrical shape, a prismatic shape, or a sheet-like shape. For
the battery structure, it includes a single-layered type, a
multi-layered type and a spiral-wound type. In the case of a
spiral-wound cylindrical battery comprising a stacked body
(comprising a separator interposed between an anode and a cathode)
wounded in multiple about a predetermined axis, it has advantages
in that the battery area can be increased as desired and a high
electric current can be flown upon operating charging and
discharging. In the case of a battery in either a prismatic form or
sheet-like form, it has an advantage in that the space of an
instrument for housing the battery can be effectively utilized.
[0147] In the following, description will be made of the shape and
structure of such a battery with reference to FIGS. 8, 9 and
10.
[0148] FIG. 8 is a schematic cross-sectional view illustrating an
example of a single-layer structure type flat battery. FIG. 9 is a
schematic cross-sectional view illustrating an example of a
spiral-wound cylindrical battery. FIG. 10 is a schematic
perspective view illustrating an example of a prismatic battery.
These batteries basically have a constitution similar to that shown
in FIG. 6 and they comprise a anode, a cathode, a separator
including an electrolyte, a battery housing and a pair of
terminals.
[0149] In FIGS. 8 and 9, reference numerals 401 (in FIG. 8)
indicates an anode comprising an anode active material layer,
reference numeral 501 (in FIG. 9) an anode active material layer,
reference 502 (in FIG. 9) an anode, each of reference numerals 403
(in FIG. 8) and 508 (in FIG. 9) a cathode comprising a cathode
active material layer, reference numeral 503 (in FIG. 9) a cathode
active material layer, each of reference numerals 405 and 505 an
anode cap (or an anode terminal), each of reference numerals 406
and 506 a cathode can (or a cathode terminal), each of reference
numerals 407 and 507 a separator with an electrolyte (or an
electrolyte solution) retained therein, and each of reference
numerals 410 and 510 a gasket (or an insulating packing).
[0150] In FIG. 9, reference numeral 500 indicates an anode
collector, reference numeral 504 indicates a cathode collector,
reference numeral 511 an insulating plate, and reference numeral
514 a safety vent.
[0151] Particularly, in the single-layer structure type flat
battery shown in FIG. 8, a stacked body comprising the cathode 403
comprising the cathode active material and the the anode 401
comprising the anode active material layer stacked through at least
the separator 407 having an electrolyte solution retained therein
is housed in the cathode can 406 on the cathode side. The anode
side of the stacked body in the cathode can 406 is sealed by the
anode cap 405 as the anode terminal and the residual inside space
of the cathode can 406 is packed by the gasket 410 (comprising an
insulating material).
[0152] In the spiral-wound cylindrical battery shown in FIG. 9, a
stacked body wounded in multiple about a predetermined axis is
housed in the cathode can 506 as the cathode terminal such that the
side face and a given bottom face side of the stacked body are
covered by the cathode can 506, said stacked body comprising at
least the separator 507 having an electrolyte solution retained
therein interposed between the cathode 508 containing the cathode
active material layer 503 formed on the cathode collector 504 and
the anode 502 containing the anode active material layer 501 formed
on the anode collector 500. In the uncovered side of the cathode
can 506, the anode cap as the anode terminal is installed. The
residual inside space of the cathode can 506 is packed by the
gasket 510 (comprising an insulating material). The stacked
electrode body having the cylindrical structure is electrically
isolated from the anode cap side through the insulating plate 511.
The anode 502 is electrically connected to the anode cap 505 by
means of the anode lead 512. Similarly, the cathode 508 is
electrically connected to the cathode can 506 by means of the
cathode lead 513. On the anode cap side, there is provided the
safety vent 514 for adjusting the internal pressure of the battery.
This safety vent can be utilized for extracting the electrolyte
solution to the outside as previously described.
[0153] The prismatic battery shown in FIG. 10 comprises a plurality
of unit cells integrated in parallel connection through a collector
in a battery housing 609 having a capping, wherein each unit cell
comprises a separator 607 having an electrolyte solution retained
therein interposed between an anode 601 comprising an anode active
material and a cathode 603 comprising a cathode active material.
The anode 601 is electrically connected to an anode terminal 605,
and the cathode 603 is electrically connected to a cathode terminal
606. The prismatic battery is provided with a plurality of safety
vents 614 at the capping of the battery housing 609.
[0154] In the following, description will be made of each battery
constituent.
[0155] As the constituent of the gasket (410, 510), there can be
used, for example, fluororesin, polyamide resin, polysulfone resin,
or various rubbers. The battery sealing is typically conducted by
way of caulking with the use of the gasket in the case of the
structure as shown in FIG. 8 or 9. Besides this, it may be
conducted by means of glass sealing, adhesive sealing, welding or
soldering.
[0156] As the constituent of the insulating plate 511 shown in FIG.
9, there can be used organic resins and ceramics.
[0157] Now, for the enclosed type battery whose constituent
components are recovered in the present invention, in the case of
such configuration as shown in FIG. 8 or 9, the electrode
terminals, cathode can and anode can serve respectively as a
battery housing corresponding to the battery housing of said
enclosed type battery in which respective battery components are
housed. Particularly, in the case of the configuration shown in
FIG. 8, the cathode can 406 and the anode cap 405 serve
respectively as a battery housing which functions also as an
outputting terminal. In the case of the configuration shown in FIG.
9, the cathode can 506 and the anode cap 505 serve respectively as
a battery housing which functions also as a terminal. The
constituent of such battery housing functioning also as the
terminal may be stainless steel, titanium clad stainless steel,
copper clad stainless steel, or nickel-plated steel.
[0158] In the configurations shown in FIGS. 8 and 9, since the
cathode can (406, 506) and the anode cap (405, 505) function
respectively also as a battery housing, they are desired to be
constituted by stainless steel.
[0159] As in the case of such configuration as shown in FIG. 10,
when neither the cathode can nor the anode can functions also as a
battery housing, the constituent of the battery housing can include
metals such as zinc, plastics such as polypropylene, and composites
of a metal or glass fiber with plastic.
[0160] For the enclosed type battery whose constituent components
are recovered in the present invention, it is desired to be
provided with an appropriate safety vent as in the case of the
configuration shown in FIG. 9 (wherein the safety vent 514 is
provided) or FIG. 10 (wherein the safety vents 614 are provided) in
order to ensure the safety when the internal pressure of the
battery is incidentally increased, by communicating the inside of
the battery with the outside to thereby reduce the increased
internal pressure of the battery. The safety vent may be
constituted by a material comprising a rubber, a spring, a metal
boll or a rupture foil. The safety vent can be utilized for
extracting the electrolyte solution present in the battery as
previously described.
[0161] In the following, description will be made of each of the
anode, cathode, separator and electrolyte of the enclosed type
battery used in the present invention.
Anode
[0162] The enclosed type battery in which an aqueous electrolyte
solution is used and whose constituent components are recovered in
the present invention includes lead-acid battery, nickel-cadmium
battery, nickel-metal hydride battery, and nickel-zinc battery.
[0163] The anode in these batteries comprises an anode active
material comprising lead, cadmium, hydrogen-absorbing alloy or
zinc, and an anode collector.
[0164] The enclosed type battery whose constituent components are
recovered in the present invention also includes various lithium
batteries. The anode in these lithium batteries comprises a
principal constituent which retains lithium therein at a stage
before operating discharging, and an anode collector.
[0165] Specific examples of such principal constituent are lithium
metals, carbonous materials in which lithium is intercalated,
transition metal oxides, and lithium alloys.
[0166] The anode collector serves to supply an electric current so
that it can be efficiently consumed for the electrode reaction upon
operating charging and discharging or to collect an electric
current generated.
[0167] The anode collector may be constituted by an appropriate
material which is highly electrically conductive and inactive to
the battery reaction.
[0168] Specific examples of such material are metals such as Ni,
Ti, Cu, Al, Pt, Pd, Au, and Zn, alloys of these metals such as
stainless steel, and composite metals of tow or more said
metals.
[0169] The anode collector may be shaped in a plate-like form,
foil-like form, mesh form, porous form-like sponge, punching metal
form, or expanded metal form.
Cathoode
[0170] The cathode in the enclosed type battery whose constituent
components are recovered in the present invention generally
comprises a cathode collector, a cathode active material, an
electrically conductive auxiliary, and a binding agent.
[0171] The cathode is usually formed by disposing a mixture of a
cathode active material, an electrically conductive auxiliary and a
binding agent on a member capable of serving as a cathode
collector.
[0172] The electrically conductive auxiliary can include graphite,
carbon blacks such as ketjen black and acetylene black, and metal
fine powders of nickel or the like.
[0173] As the binding agent in the case of using a nonaqueous
series electrolyte solution, there can be illustrated polyolefines
such as polyethylene, polypropylene, and the like; and fluororesins
such as polyvinylidene fluoride, tetrafluoroethylene polymer, and
the like.
[0174] As the binding agent in the case of using an aqueous series
electrolyte solution, there can be illustrated celluloses,
polivinyl alcohol, and polyvinyl chloride, in addition those
illustrate in the case of using the nonaqueous series electrolyte
solution.
[0175] As the cathode active material in the enclosed type battery
in which an aqueous series electrolyte solution is used and whose
constituent components are recovered in the present invention such
as lead-acid battery, nickel-cadmium battery, nickel-metal hydride
battery, or nickel-zinc battery, there is used lead oxide, nickel
(III) oxyhydroxide or nickel hydroxide.
[0176] The enclosed type battery whose constituent components are
recovered in the present invention includes also various lithium
batteries. As the cathode active material in these lithium
batteries, there is usually used a compound selected from
transition metal oxides, transition metal sulfides,
lithium-transition metal oxides, and lithium-transition metal
sulfides. The metals of these transition metal oxides and
transition metal sulfides can include metals partially having a
d-shell or f-shell. Specific examples of such metal are Sc, Y,
lanthanoids, actinoids, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc,
Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag and Au. Of these,
Ti, V, Cr, Mn, Fe, Co, Ni and Cu are particularly appropriate.
[0177] The cathode collector in the enclosed type battery whose
constituent components are recovered in the present invention
serves to supply an electric current so that it can be efficiently
consumed for the electrode reaction upon conducting the charging
and discharging or to collect an electric current generated. The
cathode collector is therefore desired to be constituted by a
material which has a high electrical conductivity and is inactive
to the battery reaction.
[0178] The material by which the cathode collector is constituted
can include Ni, Ti, Cu, Al, Pt, Pb, Au, Zn, alloys of these metals
such as stainless steel, and composite metals of two or more of
said metals.
[0179] The cathode collector may be shaped in a plate-like form,
foil-like form, mesh form, porous form-like sponge, punching metal
form, or expanded metal form.
[0180] Herein, the term "active material" in the foregoing anode or
cathode active material means a material which is involved in the
repetition of electrochemical reversible reaction of charging and
discharging in the battery. Said active material can include, in
addition to said material which is involved in the above reaction
by itself, other material capable of being involved in the above
reaction.
Separator
[0181] The separator in the enclosed type battery whose constituent
components are recovered in the present invention is disposed
between the anode and the canthode, and it serves to prevent the
anode and the cathode from suffering from internal-shorts. In
addition, the separator also serves to retain the electrolyte
solution.
[0182] The separator is required to have a porous structure capable
of allowing ions involved in the charge and discharge reaction in
the battery to pass therethrough and it is also required to be
insoluble into and stable to the electrolyte solution.
[0183] The separator is usually constituted by a nonwoven fabric or
a memberane having a micropore structure made of glass, polyolefin
such as polypropylene or polyethylene, fluororesin, or polyamide.
Alternatively, the separator may be constituted by a metal oxide
film or a resin film combined with a metal oxide respectively
having a number of micropores.
Electrolyte
[0184] For the electrolyte used in the enclosed type battery whose
constituent components are recovered in the present invention,
there can be used an appropriate electrolyte as it is, a solution
of said electrolyte dissolved in a solvent, or a material of said
solution having immobilized using a geling agent.
[0185] However, an electrolyte solution obtained by dissolving an
appropriate electrolyte in an solvent is usually used in a way that
said electrolyte solution is retained on the separator.
[0186] The higher the electrical conductivity of the electrolyte,
the better. Particularly, it is desired to use such an electrolyte
that the electrical conductivity at 25.degree. C. is preferably
1.times.10.sup.-3 S/cm or more or more preferably,
5.times.10.sup.-3 S/cm or more.
[0187] In the case of a lead-acid battery, there is used an aqueous
solution of sulfuric acid as the electrolyte.
[0188] As the electrolyte in the case of a nickel-cadmium battery,
nickel-metal hydride battery, or nickel-zinc battery, there is used
an aqueous solution of an alkali. Particularly, there is usually
used an aqueous solution of potassium hydroxide added with lithium
hydroxided.
[0189] As the electrolyte in the case of a lithium battery, there
is usually used a given electrolyte dissolved in a given
solvent.
[0190] The electrolyte can include inorganic acids such as
H.sub.2SO.sub.4, HCl and HNO.sub.3; salts of Li.sup.+(lithium ion)
with Lewis acid ion such as BF.sub.4.sup.-, PF.sub.6.sup.-,
ClO.sub.4.sup.-, CF.sub.3SO.sub.3.sup.-, or BPh.sup.4.sup.-(with Ph
being a phenyl group); and mixtures of two or more of said
salts.
[0191] Besides these, salts of the above described Lewis acids ions
with cations such as sodium ion, potassium ion, tetraalkylammonium
ion, or the like are also usable.
[0192] In any case, it is desired that the above salts are used
after they are subjected to dehydration or deoxygenation, for
example, by way of heat treatment under reduced pressure.
[0193] The solvent in which the electrolyte is dissolved can
include acetonitrile, benzonitrile, propylene carbonate, ethylene
carbonate, dimethyl carbonate, diethyl carbonate,
dimethylformamide, tetrahydrofuran, nitrobenzene, dichloroethane,
diethoxyethane, 1,2-dimethoxyethane, chlorobenzene,
.gamma.-butyrolactone, dioxolan, sulfolan, nitrometane, dimethyl
sulfide, dimethyl sulfoxide, methyl formate,
3-methyl-2-oxdazolydinone, 2-methyltetrahydrofuran,
3-propylsydonone, sulfur dioxide, phosphonyl chloride, thionyl
chloride, sulfuly chloride, and mixtures of two or more of
these.
[0194] As for these solvents, it is desired for them to be
subjected to dehydration using activated alumina, molecular sieve,
phosphorous pentaoxide, or calcium chloride, prior to their use.
Alternatively, it is possible for them to be subjected to
distillation in an atmosphere composed of inert gas in the presence
of an alkali metal, wherein moisture and foreign matters are
removed.
[0195] In order to prevent leakage of the electrolyte solution, it
is desired for the electrolyte solution to be gelated using an
appropriate gelating agent.
[0196] The gelating agent usable in this case can include polymers
having a property such that it absorbs the solvent of the
electrolyte solution to swell. Specific examples of such polymer
are polyethylene oxide, polyvinyl alcohol, and polyacrylamide.
[0197] In the following, the present invention will be described in
more detail with reference to examples, which are only for
illustrative purposes but not intended to restrict the scope of the
present invention to these examples.
EXAMPLE 1
[0198] In this example, for a prismatic nickel-metal hydride
battery having the configuration shown in FIG. 10, based on the
flow diagram shown in FIG. 1 and using the apparatus shown in FIG.
3 as a part of the previously described recovery system, the
battery housing thereof was unsealed, followed by subjecting to
washing, the resultant was dissociated into individual battery
components, and these battery components were separately
recovered.
[0199] As the above battery, there was used a used prismatic
nickel-metal hydride battery which comprises a cathode comprising a
porous nickel material whose porous structure is filled by nickel
hydroxide and nickel fine particles, an anode comprising a porous
nickel material whose porous structure is filled by a powdery
hydrogen storage alloy and a binder, an electrolyte solution
comprising an aqueous solution of potassium hydroxide added with
lithium hydroxide, and a battery housing made of
polyopropylene.
[0200] In the following, the step of decreasing the ionic
conductivity in the battery, the unsealing step, and the recovering
step will be sequentially explained with reference to FIGS. 1 and
3.
[0201] 1. A capacitor was electrically connected to the terminal of
the prismatic nickel-metal hydride battery, followed by subjecting
the battery to discharging, whereby the residual electric capacity
in the battery was transferred into the capacitor.
[0202] 2. The battery thus discharged was set to the apparatus
shown in FIG. 3 such that the safety vent-bearing face thereof was
downward faced as shown in FIG. 3.
[0203] 3. By actuating the vacuum pump of the vacuuming means 105
and opening the exhaust valve 109, the inside of the storage tank
104 was depressurized, followed by closing the exhaust valve 109.
Then, the switching valve 108 was opened to actuate the safety
vents of the battery. By this, the internal pressure of the battery
was increased and as a result, the electrolyte solution in the
battery was extracted into the extraction pipe 103, followed by
flowing into the storage tank 104. Thereafter, the leak valve 113
was opened to introduce nitrogen gas into the apparatus, whereby
the inside of the storage tank 104 was returned to atmospheric
pressure. Then, the battery whose electrolyte solution having been
extracted was detached from the apparatus.
[0204] The electrolyte solution of the battery was recovered in the
storage tank 104. The electrolyte solution thus recovered can be
recycled by filtrating and refining it.
[0205] 4. The battery whose electrolyte solution having been
extracted obtained in the step 3 was set to a high pressure water
cutting apparatus, wherein a high pressure water (containing a
powdery abrasive) of 3500 Kg/cm was sprayed onto the battery to cut
and unseal the battery housing of the battery.
[0206] 5. From the unsealed battery obtained in the step 4, the
cathode, anode and separator were taken out, washed, and dried,
then followed by classification and recovery.
[0207] In this case, because the electrolyte solution had been
extracted from the battery in the step 3, even when the anode
should have been contacted with the cathode upon taking out them,
they could be safely recovered with no energy release.
[0208] In the above, for the used prismatic nickel-metal hydride
battery before the extraction of the electrolyte solution was
conducted, the impedance between the positive and negative
terminals was measured by means of an impedance meter. As a result,
it was found to be 2 m.OMEGA.. And for the used prismatic battery
whose electrolyte solution having been extracted, the impedance
between the terminals was measured in the same manner. As a result,
it was found to be more than 5 M.OMEGA.. This indicates that by the
above cooling, the internal resistance of the battery seemingly has
been desirably increased.
[0209] In this example, description has been made of the recovery
of the prismatic nickel-metal hydride battery.
[0210] But the recovering manner of this example is not
restrictive. The recovering manner is effective in recovering other
enclosed type batteries in which a liquid electrolyte is used and
having a safety vent such as nickel-cadmium battery, lead battery
and lithium batteres including lithium ion battery.
EXAMPLE 2
[0211] In this example, for a cylindrical lithium battery having
the configuration shown in FIG. 9, based on the flow diagram shown
in FIG. 2 and using the cooling and unsealing apparatus shown in
FIG. 5, the battery housing thereof was unsealed, followed by
subjecting to washing, the resultant was dissociated into
individual battery components, and these battery components were
separately recovered.
[0212] As the above battery, there was used a spent primary lithium
battery in which a anode formed by press-laminating a lithium metal
foil on an expanded metal of nickel, a cathode formed by applying a
paste (obtained by mixing manganese dioxide (as a cathode active
material), acetylene black (as an electrically conductive
auxiliary) and polyvinylidene fluoride (as a binder)) on a nickel
mesh member and drying the resultant, a separator comprising a
polyethylene member having a number of pores, and an electrolyte
solution obtained by dissolving lithium tetrafluoroborate in an
amount of 1M (mol/l) in a mixed solvent composed of ethylene
carbonate (EC) and dimethyl carbonate (DMC) are sealed by way of
caulking. And there was used a stainless steel as the battery
housing.
[0213] In the following, the step of discharging and recovering the
residual electric capacity in the battery prior to cooling the
battery in the flow diagram in FIG. 2, the step of cooling the
battery, the unsealing step, and the recovering step will be
sequentially explained with reference to FIGS. 2 and 5.
[0214] 1. A capacitor was electrically connected to the outputting
terminal of the used cylindrical primary lithium battery, followed
by subjecting the battery to discharging, whereby the residual
electric capacity in the battery was transferred into the
capacitor.
[0215] 2. Using the cooling apparatus 201 in FIG. 5, the battery
discharged in the step 1 was immersed in a liquid nitrogen,
followed by cooling the battery to a temperature lower than the
coagulation point of the mixed organic solvent (composed of
ethylene carbonate and dimethyl carbonate) of the electrolyte
solution, whereby the ionic conductivity in the battery was
decreased.
[0216] The impedances between the positive and negative terminals
before and after the cooling treatment were measured by using the
impedance meter as in Example 1. The measured results revealed that
the impedance of before the cooling treatment is 60 m.OMEGA. and
that after the cooling treatment is more than 50 K.OMEGA..
[0217] Besides, only for the only electrolyte solution, it was
cooled under the same condition as that for cooling the battery.
And the ionic conductivities of the electrolyte before and after
the cooling treatment. As a result, the ionic conductivity before
the cooling treatment was found to seemingly have been decreased to
{fraction (1/10)}by the cooling treatment.
[0218] 3. The battery cooled in the step 2 was taken out in an Ar
gas atmosphere, it was mounted on the fixing table (207, in FIG.
5), followed by transporting by means of the transportation
mechanism (208, in FIG. 5) to the unsealing zone containing the
unsealing apparatus (204, in FIG. 5) comprising a high pressure
water cutting apparatus, wherein an extra-high pressure water of
3500 Kg/cm.sup.2 containing a powdery abrasive was sprayed onto the
battery through the nozzle to cut and unseal the battery housing of
the battery.
[0219] 4. The battery thus unsealed was subjected to washing with
methanol, where the active lithium present in the battery was
converted into lithium alcoholate. Thereafter, the resultant mixed
solvent composed of the electrolyte solution and the methanol was
recovered. From the cylindrical can as the battery housing, the
anode, separator and cathode were taken out and they were
separately recovered.
EXAMPLE 3
[0220] In this example, for a coin-like shaped rechargeable lithium
battery having the configuration shown in FIG. 8, based on the flow
diagram shown in FIG. 2 and using the cooling and unsealing
apparatus shown in FIG. 5, the battery housing thereof was
unsealed, followed by subjecting to washing, the resultant was
dissociated into individual battery components, and these battery
components were separately recovered.
[0221] As the above battery, there was used a spent coin-like
shaped rechargeable lithium battery in which a anode formed by
press-laminating a lithium metal foil on an expanded metal of
nickel, a cathode formed by applying a paste (obtained by mixing a
lithium-nickel oxide material (as a cathode active material),
acetylene black (as an electrically conductive auxiliary) and
polyvinylidene fluoride (as a binder) to obtain a mixture and and
adding N-methylpyrrolidone to said mixture) on a nickel mesh member
and drying the resultant, and a polymer solid electrolyte obtained
by dissolving lithium tetrafluoroborate in an amount of 1M (mol/1)
in a mixed solvent composed of diethyl carbonate and propylene
carbonate with an equivalent mixing ratio and solidifying the
resultant by adding polyethylene oxide thereto are sealed by way of
caulking. And there was used a stainless steel as the batter
housing of the lithium battery.
[0222] In the following, the step of discharging and recovering the
residual electric capacity in the battery prior to cooling the
battery in the flow diagram in FIG. 2, the step of cooling the
battery, the unsealing step, and the recovering step will be
sequentially explained with reference to FIGS. 2 and 5.
[0223] As the cooling means (the cooling apparatus 201 in FIG. 5),
there was used a cooling apparatus (trademark name: VORTEX TUBE,
produced by VORTEX Company of the United States) in which a
compressed gas. As the compressed gas, there was used CO.sub.2
gas.
[0224] 1. CO.sub.2 gas of 5 Kg/cm.sup.2 was fed through the gas
supply port of the foregoing cooling apparatus 201 to spray a
CO.sub.2 cold blast of -40.degree. C. onto the used coin-like
shaped rechargeable lithium battery, whereby the battery was cooled
to a temperature lower than the glass transition point of the
polyethylene oxide of the polymer solid electrolyte.
[0225] The impedances between the positive and negative terminals
of the used battery before and after the cooling treatment were
measured in the same manner as in Example 1. The measured results
revealed that the impedance of before the cooling treatment is 500
m.OMEGA. and that after the cooling treatment is more than 5
M.OMEGA.. Based on this and the result of the measurement of the
ionic conductivities of the electrolyte solution in the same manner
as in Example 2, the ionic conductivity before the cooling
treatment was found to seemingly have been decreased to {fraction
(1/10)}as a result of the cooling treatment.
[0226] 2. The battery cooled in the step 2 was taken out in a
CO.sub.2 gas atmosphere, it was mounted on the fixing table (207,
in FIG. 5), followed by transporting by means of the transportation
mechanism (208, in FIG. 5) to the unsealing zone containing the
unsealing apparatus (204, in FIG. 5) comprising a YAG laser cutting
apparatus, wherein laser beam was irradiated onto the battery to
cut and unseal the battery housing of the battery.
[0227] 3. From the cut rechargeable battery can as the battery
housing, the anode, polymer solid electrolyte and cathode were
taken out and they were separately recovered.
EXAMPLE 4
[0228] In this example, for a cylindrical rechargeable lithium
battery having the configuration shown in FIG. 9, based on the flow
diagram shown in FIG. 2 and using the cooling and unsealing
apparatus shown in FIG. 5, the battery housing thereof was
unsealed, followed by subjecting to washing, the resultant was
dissociated into individual battery components, and these battery
components were separately recovered.
[0229] As the above battery, there was used a used cylindrical
rechargeable lithium battery in which a anode formed by applying a
paste (obtained by mixing a natural graphite with polyvinylidene
fluoride (as a binder) to obtain a mixture and adding
N-methylpyrrolidone to said mixture) on a copper foil and drying
the resultant, a cathode formed by applying a paste (obtained by
mixing a lithium-cobalt oxide material (as a cathode active
material), acetylene black (as an electrically conductive
auxiliary) and polyvinylidene fluoride (as a binder) to obtain a
mixture and adding N-methylpyrrolidone to said mixture) on an
aluminum foil and drying the resultant, a separator comprising a
polyethylene member having a number of pores, and an electrolyte
solution obtained by dissolving lithium tetrafluoroborate in an
amount of 1M (mol/l) in a mixed solvent composed of ethylene
carbonate (EC) and dimethyl carbonate (DMC) with an equivalent
mixing ratio are sealed by way of caulking. There was used a
stainless steel as the battery housing of the battery.
[0230] In the following, the step of discharging and recovering the
residual electric capacity in the battery prior to cooling the
battery in the flow diagram in FIG. 2, the step of cooling the
battery, the unsealing step, and the recovering step will be
sequentially explained with reference to FIGS. 2 and 5.
[0231] As the cooling means (the cooling apparatus 201 in FIG. 5),
there was used a cooling apparatus (trademark name: VORTEX TUBE,
produced by VORTEX Company of the United States) in which a
compressed gas. As the compressed gas, there was used Ar gas.
[0232] 1. A capacitor was electrically connected to the outputting
terminal of the cylindrical rechargeable lithium battery, followed
by subjecting the battery to discharging, whereby the residual
electric capacity in the battery was transferred into the
capacitor.
[0233] 2. Ar gas of 7 Kg/cm.sup.2 was fed through the gas supply
port of the foregoing cooling apparatus 201 to spray an Ar cold
blast of -30.degree. C. onto the spent cylindrical rechargeable
lithium battery discharged in the step 1, whereby the battery was
cooled to a temperature lower than the coaguration point of the
mixed solvent (composed of the ethylene carbonate and dimethyl
carbonate) of the electrolyte solution.
[0234] The impedances between the positive and negative terminals
before and after the cooling treatment were measured in the same
manner as in Example 1. The measured results revealed that the
impedance of before the cooling treatment is 80 m.OMEGA. and that
after the cooling treatment is more than 5 k.OMEGA.. Based on this
and the result of the measurement of the ionic conductivity of the
electrolyte solution in the same manner as in Example 2, the ionic
conductivity before the cooling treatment was found to seemingly
have been-decreased to {fraction (1/10)}as a result of the cooling
treatment.
[0235] 3. The battery cooled in the step 2 was taken out in an Ar
gas atmosphere, it was mounted on the fixing table (207, in FIG.
5), followed by transporting by means of the transportation
mechanism (208, in FIG. 5) to the unsealing zone containing the
unsealing apparatus (204, in FIG. 5) comprising an extra-high
pressure cutting apparatus, wherein an extra-high pressure water
(containing a powdery abrasive) of 3500 Kg/cm.sup.2 was sprayed
onto the battery to cut and unseal the battery housing of the
battery.
[0236] 4. The battery thus unsealed was subjected to washing with
water, where the active lithium present in the battery was
converted into lithium hydroxide. Thereafter, it was further
washed, where the resultant mixed solvent composed of the
electrolyte solution, methanol and water was recovered. From the
cylindrical can as the battery housing, the anode, separator and
cathode were taken out and they were separately recovered. The
above mixed solvent composed of the electrolyte solution, methanol
and water was subjected to distillation, where the electrolyte,
organic solvent and methanol were separately recovered.
EXAMPLE 5
[0237] In this example, using a used cylindrical rechargeable
lithium battery having the same constitution as that of the
cylindrical rechargeable lithium battery used in Example 4 and
based on the flow diagram shown in FIG. 2, the battery housing
thereof was unsealed, followed by subjecting to washing, the
resultant was dissociated into individual battery components, and
these battery components were separately recovered.
[0238] In the following, the step of discharging and recovering the
residual electric capacity in the battery prior to cooling the
battery in the flow diagram in FIG. 2, the step of cooling the
battery, the unsealing step, and the recovering step will be
sequentially explained with reference to FIG. 2.
[0239] 1. A capacitor was electrically connected to the outputting
terminal of the cylindrical rechargeable lithium battery, followed
by subjecting the battery to discharging, whereby the residual
electric capacity in the battery was transferred into the
capacitor.
[0240] 2. The spent cylindrical rechargeable lithium battery
discharged in the step 1 was immersed in a vessel filled with
water, followed by subjecting to quick freezing, whereby the
battery was sealed in an ice.
[0241] The impedances between the positive and negative terminals
of the used battery before and after the cooling treatment were
measured in the same manner as in Example 1. The measured results
revealed that the impedance of before the cooling treatment is 80
m.OMEGA. and that after the cooling treatment is more than 3
k.OMEGA.. Based on this and the result of the measurement of the
ionic conductivity of the electrolyte solution in the same manner
as in Example 2, the ionic conductivity before the cooling
treatment was found to seemingly have been decreased to {fraction
(1/10)}by the cooling treatment.
[0242] 3. The battery sealed in the ice in the step 2 was taken out
in a nitrogen gas atmosphere, it was mounted on a fixing table,
followed by transporting to a disk cutter capable of rotating at a
high speed to conduct cutting for an object, where the battery
sealed in the ice was cut whereby the battery housing of the
battery was unsealed.
[0243] 4. The battery thus unsealed was thawed, followed by washing
with acetone, where the resultant mixed solvent composed of the
electrolyte solution, acetone and water was recovered. From the
cylindrical can as the battery housing, the anode, separator and
cathode were taken out and they were separately recovered. The
above mixed solvent composed of the electrolyte solution, acetone
and water was subjected to distillation, where the electrolyte,
organic solvent and methanol were separately recovered.
EXAMPLE 6
[0244] In this example, for a prismatic rechargeable lithium
battery having the configuration shown in FIG. 10, based on the
flow diagram shown in FIG. 2, the battery housing thereof was
unsealed, followed by subjecting to washing, the resultant was
dissociated into individual battery components, and these battery
components were separately recovered. Though not shown in FIG. 10,
in said prismatic rechargeable lithium battery, a battery housing
made of an aluminum alloy and a battery caping provided with a pair
of outputting and inputting terminals and a plurality of safety
vents are assembled through an O-ring and with bises.
[0245] As the above battery, there was used a used prismatic
rechargeable lithium battery in which a anode formed by applying a
paste (obtained by mixing a natural graphite with polyvinylidene
fluoride (as a binder) to obtain a mixture and adding
N-methyl-2-pyrrolidone to said mixture) on a copper foil and drying
the resultant, a cathode formed by applying a paste (obtained by
mixing a lithium-cobalt oxide material (as a cathode active
material), acetylene black (as an electrically conductive
auxiliary) and polyvinylidene fluoride (as a binder) to obtain a
mixture and adding N-methylpyrrolidone to said mixture) on an
aluminum foil and drying the resultant, a separator comprising a
polyethylene member having a number of pores, and an electrolyte
solution obtained by dissolving lithium tetrafluoroborate in an
amount of 1M (mol/l) in a mixed solvent composed of ethylene
carbonate (EC) and dimethyl carbonate (DMC) with an equivalent
mixing ratio are sealed, and a blade spring for pressing in order
to shorten the distance between the cathode and anode is
inserted.
[0246] In the following, the step of discharging and recovering the
residual electric capacity in the battery prior to cooling the
battery in the flow diagram in FIG. 2, the step of cooling the
battery, the unsealing step, and the recovering step will be
sequentially explained with reference to FIG. 2.
[0247] As the cooling means, there was used dryice-metahanol.
[0248] 1. A capacitor was electrically connected to the outputting
terminal of the prismatic rechargeable lithium battery, followed by
subjecting the battery to discharging, whereby the residual
electric capacity in the battery was transferred into the
capacitor.
[0249] 2. The used prismatic rechargeable lithium battery
discharged in the step 1 was immersed in a dryice-methanol freezing
agent obtained by adding a dryice to methanol, whereby the battery
was cooled to a temperature lower than the coaguration point of the
mixed solvent (composed of the ethylene carbonate and dimethyl
carbonate) of the electrolyte solution to decrease the ionic
conductivity in the battery.
[0250] The impedances between the positive and negative terminals
of the battery before and after the cooling treatment were measured
in the same manner as in Example 1. The measured results revealed
that the impedance of before the cooling treatment is 70 m.OMEGA.
and that after the cooling treatment is more than 1 M.OMEGA.. Based
on this and the result of the measurement of the ionic conductivity
of the electrolyte solution in the same manner as in Example 2, the
ionic conductivity before the cooling treatment was found to
seemingly have been decreased to {fraction (1/10)}as a result of
the cooling treatment.
[0251] 3. The battery cooled in the step 2 was taken out in an Ar
gas atmosphere, and the vises were loosen to detach the battery
capping having the safety vents, whereby the battery housing was
unsealed.
[0252] 4. From the battery thus unsealed, the anode, separator,
cathode and blade spring were taken out, followed by subjecting to
washing with metanol, and the anode, separator, cathode, and blade
spring and also the mixed solvent composed of the electrolyte
solution and the methanoly were separately recovered. The mixed
solution composed of the electrolyte solution and methanol was
subjected to distillation, where the electrolyte, organic solvent
and methanol were separately recovered.
[0253] Incidentally, in each of the foregoing examples 2 to 6, the
recovery operation was conducted for 10 batteries, where neither
smoke nor spark were occurred, the battery components were not
damaged due to burning or the like and the battery components could
be desirably recovered in any case.
[0254] In each of the foregoing examples 2 to 6, description has
been made of the recovery of the enclosed type lithium battery. But
the recovering manner of any of these examples is not restrictive.
The recovering manner described any of these examples is effective
in recovering other enclosed type batteries as nickel-metal hydride
battery, nickel-cadmium battery, lead battery and the like.
[0255] As above described, according to the present invention, for
any spent, enclosed type batteries, its constituent components can
be more safely recovered while desirably preventing them from being
damaged and at a high recovery. And the recovering apparatus
(system) enables to relatively easily recover the components of an
enclosed type battery at a reasonable cost.
* * * * *