U.S. patent application number 14/390325 was filed with the patent office on 2015-02-19 for air cell.
The applicant listed for this patent is NISSAN MOTOR CO., LTD.. Invention is credited to Atsushi Miyazawa, Mori Nagayama, Yoshiko Tsukada.
Application Number | 20150050569 14/390325 |
Document ID | / |
Family ID | 49300362 |
Filed Date | 2015-02-19 |
United States Patent
Application |
20150050569 |
Kind Code |
A1 |
Tsukada; Yoshiko ; et
al. |
February 19, 2015 |
AIR CELL
Abstract
An air cell includes a plurality of electrode structures each
including a filling chamber for an electrolyte liquid interposed
between an air electrode and a metal negative electrode; an
electrode housing portion individually housing the plural electrode
structures; and a liquid supply unit which supplies the electrolyte
liquid to the plural electrode structures. The electrode housing
portion includes a plurality of liquid injection holes to inject
the electrolyte liquid into the filling chambers of the respective
electrode structures and a plurality of liquid junction prevention
portions each dividing a space between the liquid injection holes
adjacent to each other. The liquid supply unit includes a liquid
injection device allowing the electrolyte liquid to flow into the
plural liquid injection holes.
Inventors: |
Tsukada; Yoshiko;
(Yokohama-shi, JP) ; Nagayama; Mori;
(Yokohama-shi, JP) ; Miyazawa; Atsushi;
(Kamakura-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NISSAN MOTOR CO., LTD. |
Yokohama-shi, Kanagawa |
|
JP |
|
|
Family ID: |
49300362 |
Appl. No.: |
14/390325 |
Filed: |
March 12, 2013 |
PCT Filed: |
March 12, 2013 |
PCT NO: |
PCT/JP2013/056753 |
371 Date: |
October 2, 2014 |
Current U.S.
Class: |
429/405 |
Current CPC
Class: |
H01M 2250/20 20130101;
Y02E 60/50 20130101; H01M 8/04283 20130101; H01M 2/362 20130101;
H01M 2220/20 20130101; H01M 12/02 20130101; H01M 12/06 20130101;
H01M 12/065 20130101; H01M 12/08 20130101; H01M 2220/10 20130101;
H01M 6/32 20130101 |
Class at
Publication: |
429/405 |
International
Class: |
H01M 8/04 20060101
H01M008/04; H01M 12/02 20060101 H01M012/02; H01M 12/08 20060101
H01M012/08 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 4, 2012 |
JP |
2012-085301 |
Apr 4, 2012 |
JP |
2012-085303 |
Claims
1. An air cell comprising: plural electrode structures each
including a filling chamber for an electrolyte liquid interposed
between an air electrode and a metal negative electrode; an
electrode housing portion individually housing the plural electrode
structures; and a liquid supply unit which supplies the electrolyte
liquid to the plural electrode structures, wherein the plural
electrode structures are arranged in series in the electrode
housing portion, the electrode housing portion includes plural
liquid injection holes to inject the electrolyte liquid into the
filling chambers of the respective electrode structures and plural
liquid junction prevention portions each dividing a space between
the liquid injection holes adjacent to each other, the liquid
supply unit includes a storage tank for the electrolyte liquid and
a liquid injection device allowing the electrolyte liquid in the
storage tank to flow into the plural liquid injection holes, and
the liquid injection device and the liquid injection holes are
separated from each other and there is no interposition between the
liquid injection device and the liquid injection holes.
2. The air cell according to claim 1, wherein the electrode housing
portion is further provided with liquid junction prevention
portions located towards arrangement end portions with respect to
the liquid injection holes for injecting the electrolyte liquid
into the filling chambers of the electrode structures located at
the arrangement end portions.
3. The air cell according to claim 1, wherein the plural liquid
junction prevention portions each have a protruding structure.
4. The air cell according to claim 3, wherein at least one of the
plural liquid junction prevention portions has a surface inclined
downward to the liquid injection hole adjacent thereto.
5. The air cell according to claim 4, wherein at least one of the
plural liquid junction prevention portions has a triangular
cross-section.
6. The air cell according to claim 4, wherein at least one of the
plural liquid junction prevention portions has a trapezoidal
cross-section.
7. The air cell according to claim 3, wherein at least one of the
plural liquid junction prevention portions has a downward step
towards at least one liquid injection hole adjacent thereto.
8. The air cell according to claim 3, wherein at least one of the
plural liquid junction prevention portions has a concave curved
surface inclined downward at least one liquid injection hole
adjacent thereto.
9. The air cell according to claim 3, wherein at least one of the
plural liquid junction prevention portions has a convex curved
surface inclined downward at least to one liquid injection hole
adjacent thereto.
10. The air cell according to claim 3, wherein at least one of the
plural liquid junction prevention portions includes plural
projections arranged at predetermined intervals in an arrangement
direction of the plural electrode structures.
11. The air cell according to claim 10, wherein the plural
projections have a common height.
12. The air cell according to claim 10, wherein the plural
projections have different heights.
13. The air cell according to claim 1, wherein the liquid injection
device includes a switching body which controls a flow of the
electrolyte liquid.
14. The air cell according to claim 1, wherein the liquid injection
device is placed to allow the electrolyte liquid to concurrently
flow into the plural liquid injection holes.
15. The air cell according to claim 1, wherein more than one liquid
injection device is provided to correspond to the respective liquid
injection holes.
16. The air cell according to claim 1, wherein the liquid injection
device is placed at a position separate from the plural liquid
junction prevention portions.
17. The air cell according to claim 1, wherein at least a
peripheral surface of the liquid injection device has water
repellency.
18. The air cell according to claim 3, wherein at least one of top
surfaces of the plural liquid junction prevention portions has
water repellency.
19. The air cell according to claim 1, wherein at least one of
peripheries of openings of the plural liquid injection holes is a
hydrophilic region having hydrophilicity.
20. The air cell according to claim 19, wherein an outer side of at
least one of the peripheries of the openings of the plural liquid
injection holes has a water-repellent region having water
repellency.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority from
Japanese Patent Application No. 2012-085301, filed on Apr. 4, 2012,
and Japanese Patent Application No. 2012-085303, filed on Apr. 4,
2012, the entire contents of all of which are incorporated herein
by reference.
TECHNICAL FIELD
[0002] The present invention relates to an air cell using oxygen as
a positive electrode active material, and particularly, relates to
an injection-type air cell into which an electrolyte liquid can be
injected at the time of use.
BACKGROUND
[0003] There has been known an air cell, for example, as described
in Japanese Unexamined Patent Application Publication No.
S62-177873. The air cell described in Japanese Unexamined Patent
Application Publication No. S62-177873 includes a frame including
electrodes and a tank housing the frame and an electrolysis
solution. The frame includes a pair of cathodes arranged at a
predetermined interval and anodes each being placed to be opposed
to the outer side of each cathode.
[0004] The air cell has a configuration in which the frame and the
tank are provided with fin-shaped portions and grooves
respectively. The fin-shaped portions engage with the grooves when
the frame and the tank are assembled together so that two
electrolyte holding regions electrically separated from each other
are formed in the tank. Accordingly, generation of a current path
(liquid junction) via the electrolysis solution between the anodes
can be avoided. In addition, the air cell is provided with a
non-conductive baffle between the paired cathodes. Therefore, a
current flow can be prevented from being generated between the
cathodes even if a liquid enters the space between the cathodes.
The above-described air cell uses, for example, seawater as the
electrolysis solution. The air cell is dropped into the sea so as
to introduce seawater into the tank and thereby start power
generation.
SUMMARY
[0005] In recent years, research and development of air cells used
for power supplies or auxiliary power supplies in motor vehicles is
being carried out. An air cell mounted in a vehicle is required to
ensure output performance and capacity necessary for the vehicle
and therefore required to have a configuration in which a plurality
of electrode structures are arranged in series and use a strong
alkaline electrolysis solution.
[0006] In the conventional air cell, since the fin-shaped portions
and the grooves merely engage with each other at partitioning
portions between the electrolyte holding regions, a liquid junction
via the electrolysis solution cannot be completely prevented
between the anodes. Thus, there is a problem of applying the
conventional configuration to an air cell with high output power
and high capacity using a strong alkaline electrolysis
solution.
[0007] The air cell using seawater as the electrolysis solution has
no practical problem with regard to a slight liquid junction, since
the electrolysis solution has low resistance and the output power
is small in such an air cell. On the other hand, any liquid
junction should be prevented in an air cell using a strong alkaline
electrolysis solution because the resistance of the electrolysis
solution is high.
[0008] The present invention has been made in view of the
above-described conventional problem. An object of the present
invention is to provide an injection-type air cell including a
plurality of electrode structures arranged in series, and
particularly, an air cell capable of reliably preventing a liquid
junction between the electrode structures via an electrolyte
liquid.
[0009] An air cell according to an aspect of the present invention
includes: a plurality of electrode structures each including a
filling chamber for an electrolyte liquid interposed between an air
electrode and a metal negative electrode; an electrode housing
portion individually housing the plural electrode structures; and a
liquid supply unit which supplies the electrolyte liquid to the
plural electrode structures, wherein the plural electrode
structures are arranged in series in the electrode housing portion,
the electrode housing portion includes a plurality of liquid
injection holes to inject the electrolyte liquid into the filling
chambers of the respective electrode structures and a plurality of
liquid junction prevention portions each dividing a space between
the liquid injection holes adjacent to each other, and the liquid
supply unit includes a storage tank for the electrolyte liquid and
a liquid injection device allowing the electrolyte liquid in the
storage tank to flow into the plural liquid injection holes.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1A is a cross-sectional view of an air cell according
to a first embodiment of the present invention.
[0011] FIG. 1B is a side view of the air cell according to the
first embodiment of the present invention.
[0012] FIG. 2 is a block diagram schematically showing an air cell
system including an air cell in which a liquid supply unit shown in
FIG. 1A is further equipped with a controller and a pipe.
[0013] FIG. 3A is a cross-sectional view of an air cell according
to a first modified example of the first embodiment of the present
invention.
[0014] FIG. 3B is a side view of the air cell according to the
first modified example of the first embodiment of the present
invention.
[0015] FIG. 4A is a cross-sectional view of an air cell according
to a second modified example of the first embodiment of the present
invention.
[0016] FIG. 4B is a perspective view of a liquid junction
prevention portion according to the second modified example of the
first embodiment of the present invention.
[0017] FIG. 5A is a cross-sectional view of an air cell according
to a third modified example of the first embodiment of the present
invention.
[0018] FIG. 5B is a perspective view of a liquid junction
prevention portion according to the third modified example of the
first embodiment of the present invention.
[0019] FIG. 6A is a perspective view for explaining another form of
the liquid junction prevention portion according to the third
modified example of the first embodiment of the present
invention.
[0020] FIG. 6B is a perspective view for explaining yet another
form of the liquid junction prevention portion according to the
third modified example of the first embodiment of the present
invention.
[0021] FIG. 6C is a perspective view for explaining yet another
form of the liquid junction prevention portion according to the
third modified example of the first embodiment of the present
invention.
[0022] FIG. 7A is a cross-sectional view of an air cell according
to a fourth modified example of the first embodiment of the present
invention.
[0023] FIG. 7B is a cross-sectional view for explaining another
form of a liquid junction prevention portion according to the
fourth modified example of the first embodiment of the present
invention.
[0024] FIG. 8A is a cross-sectional view of an air cell according
to a fifth modified example of the first embodiment of the present
invention while showing a state during injection of an electrolyte
liquid.
[0025] FIG. 8B is a cross-sectional view of the air cell according
to the fifth modified example of the first embodiment of the
present invention while showing a state after injection of the
electrolyte liquid.
[0026] FIG. 9A is a cross-sectional view of an air cell according
to a sixth modified example of the first embodiment of the present
invention.
[0027] FIG. 9B is a partly enlarged view of a liquid injection
device according to the sixth modified example of the first
embodiment of the present invention.
[0028] FIG. 10A is a cross-sectional view of an air cell according
to a seventh modified example of the first embodiment of the
present invention.
[0029] FIG. 10B is a side view of the air cell according to the
seventh modified example of the first embodiment of the present
invention.
[0030] FIG. 10C is a partly enlarged view of a liquid junction
prevention portion according to the seventh modified example of the
first embodiment of the present invention.
[0031] FIG. 11A is a cross-sectional view of an air cell according
to an eighth modified example of the first embodiment of the
present invention.
[0032] FIG. 11B is a partly enlarged view of a liquid injection
hole according to the eighth modified example of the first
embodiment of the present invention.
[0033] FIG. 11C is a partly enlarged view of the liquid injection
hole according to the eighth modified example of the first
embodiment of the present invention.
[0034] FIG. 12A is a cross-sectional view of an air cell according
to a second embodiment of the present invention.
[0035] FIG. 12B is an enlarged cross-sectional view of an upper
portion of an electrode housing portion according to the second
embodiment of the present invention.
[0036] FIG. 13A is a cross-sectional view of an air cell according
to a first modified example of the second embodiment of the present
invention.
[0037] FIG. 13B is an enlarged cross-sectional view of an upper
portion of an electrode housing portion according to the first
modified example of the second embodiment of the present
invention.
[0038] FIG. 14A is a cross-sectional view of an air cell according
to a second modified example of the second embodiment of the
present invention while showing a state during injection of an
electrolyte liquid.
[0039] FIG. 14B is a cross-sectional view of the air cell according
to the second modified example of the second embodiment of the
present invention while showing a state after injection of the
electrolyte liquid.
[0040] FIG. 15A is a cross-sectional view of an air cell according
to a third modified example of the second embodiment of the present
invention.
[0041] FIG. 15B is an enlarged cross-sectional view of a liquid
injection device and an upper portion of an electrode housing
portion according to the third modified example of the second
embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
First Embodiment
[0042] An air cell C1 shown in FIG. 1A includes a plurality of
electrode structures 1, an electrode housing portion 2 having a
plurality of housing compartments individually housing the plural
electrode structures 1, and a liquid supply unit 3 for supplying an
electrolyte liquid to the plural electrode structures 1, each
electrode structure 1 including an air electrode 11, a metal
negative electrode 12 and a filling chamber 13 for the electrolyte
liquid interposed between the respective electrodes. Here, each of
the electrode structures 1 serves as a single cell (an air cell)
once the electrolyte liquid is supplied thereto. Thus, the air cell
C1 according to the present embodiment is an assembly of single
cells and is also referred to as an assembled battery.
[0043] Each of the electrode structures 1 is formed into a
rectangular plate as a whole. The air electrode 11 includes a
positive electrode member and a water-repellent layer placed as an
outermost layer of the air electrode 11 (not shown in the figure).
The positive electrode member contains, for example, a catalyst
component and an electric conductive catalyst carrier on which the
catalyst component is supported.
[0044] In particular, the catalyst component is metal selected as
appropriate from platinum (Pt), ruthenium (Ru), iridium (Ir),
silver (Ag), rhodium (Rh), palladium (Pd), osmium (Os), tungsten
(W), lead (Pb), iron (Fe), chromium (Cr), cobalt (Co), nickel (Ni),
manganese (Mn), vanadium (V), molybdenum (Mo), gallium (Ga), and
aluminum (Al), or an alloy of these metals arbitrarily combined
together. The shape and size of the catalyst component are not
particularly limited, and any shape and size similar to those used
in conventionally-known catalyst components may be used. However,
the catalyst component is preferably in a particle state. The
average particle diameter of catalyst particles is preferably in a
range from 1 nm to 30 nm. When the average particle diameter of the
catalyst particles is within the range from 1 nm to 30 nm, a
balance of ease of support of the catalyst component and a catalyst
utilization rate with regard to an effective electrode area in
which an electrochemical reaction progresses, can be controlled as
appropriate.
[0045] The catalyst carrier functions as a carrier for supporting
the catalyst component as described above and as an electron
conducting path involved in electron communication between the
catalyst component and other substances. The catalyst carrier is
not particularly limited as long as it has a specific surface area
sufficient to support the catalyst component in a desired dispersed
state and has sufficient electron conductivity, and preferably
contains carbon as a main component. A specific example of the
catalyst carrier may be carbon particles containing carbon black,
activated carbon, coke, natural graphite or artificial graphite.
The size of the catalyst carrier is not particularly limited;
however, an average particle diameter of the catalyst carrier may
be approximately in a range from 5 nm to 200 nm, preferably
approximately in a range from 10 nm to 100 nm, in view of ease of
support, the catalyst utilization rate, the thickness of the
catalyst layer adjusted within an appropriate range, and the
like.
[0046] The supported amount of the catalyst component in the
positive electrode member is preferably in a range from 10% to 80%
by mass, more preferably in a range from 30% to 70% by mass, with
respect to the total amount of the positive electrode member.
However, the positive electrode member is not limited thereto, and
conventionally-known materials applied to air cells may be
used.
[0047] The water-repellent layer has a liquid-tight (watertight)
property with respect to the electrolyte liquid and has air
permeability with respect to oxygen. The water-repellent layer
includes a water-repellent film such as polyolefin or fluorine
resin in order to prevent leakage of the electrolyte liquid, and
also has a large number of fine pores in order to supply oxygen to
the positive electrode member.
[0048] The metal negative electrode 12 includes a negative
electrode active material containing a single substance of metal or
an alloy having a standard electrode potential which is less noble
than that of hydrogen. Examples of a single substance of metal
having a standard electrode potential less noble than that of
hydrogen, include zinc (Zn), iron (Fe), aluminum (Al), magnesium
(Mg), manganese (Mn), silicon (Si), titanium (Ti), chromium (Cr),
and vanadium (V). The alloy may be obtained in such a manner as to
add, to the metal element as listed above, one or more kinds of
metal elements or non-metal elements. However, the material is not
limited thereto, and conventionally-known materials applied to air
cells may be used.
[0049] The electrode housing portion 2 has a configuration in which
the plural electrode structures 1 are each formed into a
rectangular plate and kept in a standing state, and are arranged in
series in the horizontal direction and individually housed in each
of the plural housing compartments. Each of the housing
compartments of the electrode housing portion 2 is provided with an
air chamber 21 located towards the air electrode 11 of each
electrode structure 1. The electrode housing portion 2 further
includes a plurality of liquid injection holes 22 formed at the
upper portion of the electrode housing portion 2 through which the
electrolyte liquid is injected into the plural filling chambers 13
of the electrode structures 1, and a plurality of liquid junction
prevention portions 51 having a protruding structure so that a
space between the liquid injection holes 22 adjacent to each other
is divided by each liquid junction prevention portion 51.
[0050] The plural liquid junction prevention portions 51 of the
present embodiment are each formed into a rib as shown in FIG. 1.
The electrode housing portion 2 is further provided with liquid
junction prevention portions 51 located towards the end portions in
the arrangement direction with respect to the liquid injection
holes 22 for injecting the electrolyte liquid into the filling
chambers 13 of the electrode structures 1 located at the end
portions in the arrangement direction. In other words, the liquid
junction prevention portions 51 are also located on both sides of
each liquid injection hole 22.
[0051] As shown in FIG. 1A and FIG. 1B, the liquid supply unit 3
includes a storage tank 31 for the electrolyte liquid, and a
plurality of liquid injection devices 32 located above the
respective liquid injection holes 22 to allow the electrolyte
liquid in the storage tank 31 to flow into the liquid injection
holes 22. In the present embodiment, each liquid injection device
32 includes a switching body 41 which controls the flow of the
electrolyte liquid. The plural liquid injection devices 32 are
located to face the corresponding liquid injection holes 22. The
switching body 41 is a switching valve. The plural liquid injection
devices 32 are each located at a position vertically separate from
the liquid junction prevention portions 51.
[0052] The electrolyte liquid stored in the liquid supply unit 3 is
an electrolysis solution or, for example, a liquid (water) for
dissolving a solid electrolyte placed or mixed in the electrode
structures 1 or in a pipe 35 (shown in FIG. 2) installed from the
storage tank 31 to the respective liquid injection devices 32. In
the case of using the electrolysis solution, an aqueous solution of
potassium chloride, sodium chloride, or potassium hydroxide may be
applicable. However, the electrolyte liquid is not limited thereto,
and conventionally-known electrolysis solutions applied to air
cells may be used. The amount of the electrolyte liquid is
determined in view of a discharge time of the air cell C1, a
precipitation amount of metal salt produced at the time of
discharge, or the like.
[0053] FIG. 2 is a block diagram schematically showing an air cell
system including an air cell C1' in which the liquid supply unit 3
shown in FIG. 1 is further equipped with a controller 33 and the
pipe 35. Each of the electrode structures 1 includes a case housing
the air electrode 11 and the metal negative electrode 12 so as to
serve as a cartridge, and is housed in each of the housing
compartments of the electrode housing portion 2 as indicated by the
arrow in the figure. The electrode housing portion 2 is provided
with a cover (not shown in the figure) placed on the respective
housing compartments. The cover may also be provided with the
liquid injection holes 22 and the liquid junction prevention
portions 51.
[0054] The electrode housing portion 2 further includes a busbar 23
inside thereof on which the plural electrode structures 1 housed in
the electrode housing portion 2 are connected in series. The air
cell C1' supplies electric power to a driven body 5 such as a motor
via a controller 4.
[0055] The electrode housing portion 2 is further connected with an
air supply unit 6. The air supply unit 6 supplies air to the air
chambers 21 adjacent to the electrode structures 1 in the
respective housing compartments. The air supply unit 6 includes an
air compressor, a flow amount control valve, pipes, and the
like.
[0056] The liquid supply unit 3 includes the storage tank 31, the
liquid injection devices 32, the pipe 35 and the controller 33 that
controls the flow of the electrolyte liquid. The controller 33
includes a pump, a flow amount control valve, and the like. Instead
of the configuration of the air cell C1 shown in FIG. 1 in which
the storage tank 31 and the liquid injection devices 32 are
directly connected together, the air cell C1' may have a
configuration in which the storage tank 31 and the liquid injection
devices 32 are provided separately from each other, as shown in
FIG. 2.
[0057] In the air cell C1 configured as described above, the liquid
supply unit 3 opens the switching bodies (the switching valves) 41
of the respective liquid injection devices 32 so that the
electrolyte liquid flows down through the liquid injection holes 22
to be injected into the filling chambers 13 of the respective
electrode structures 1. Accordingly, each of the electrode
structures 1 serves as a single cell (an air cell) to start power
generation.
[0058] Here, a slight amount of the electrolyte liquid may remain
on the upper surface of the electrode housing portion 2 after the
injection of the electrolyte liquid. In order to deal with such a
problem, the air cell C1 includes the plural liquid junction
prevention portions 51 each having a protruding structure and
dividing the space between the liquid injection holes 22 adjacent
to each other. Thus, the remaining electrolyte liquid does not flow
into the adjacent liquid injection hole 22. Accordingly, the air
cell C1 can reliably prevent a liquid junction between the
electrode structures (the single cells) 1 adjacent to each other,
namely, a short circuit via the electrolyte liquid. Therefore, the
air cell C1 can be applied appropriately to an air cell with high
output power and high capacity using an electrolysis solution
having high resistance, such as a strong alkaline electrolysis
solution, in which any liquid junction should be prevented. The air
cell C1 is thus remarkably suitable for an onboard power supply for
a vehicle or the like which is required to have high output power
and high capacity.
[0059] In addition, the air cell C1 has a configuration in which
the electrode housing portion 2 is provided with the liquid
junction prevention portions 51 also at the end portions in the
arrangement direction of the electrode structures 1. This
configuration can prevent the electrolyte liquid from flowing out
of the air cell C1 at the time of injecting the electrolyte
liquid.
[0060] Further, the air cell C1 uses the storage tank 31 as a
common tank for the plural electrode structures 1 so as to simplify
the structure thereof and reduce costs. In addition, since the
liquid injection devices 32 each include the switching body (the
switching valve) 41, the amount of the electrolyte liquid used can
be adjusted. Since the switching bodies 41 are closed after the
electrolyte liquid is injected, a liquid junction via the
electrolyte liquid in the storage tank 31 can be prevented.
[0061] Further, the air cell C1 is provided with the plural liquid
injection devices 32 in such a manner as to face the corresponding
liquid injection holes 22. Therefore, the electrolyte liquid can be
injected rapidly into the respective electrode structures 1, which
can contribute to shortening the startup time. Further, since the
air cell C1 can inject the electrolyte liquid only into the
selected electrode structures 1, the air cell C1 can selectively
start a particular number of the electrode structures (the single
cells) 1 depending on the required amount of electricity. The air
cell C1 can also easily deal with automatic control of liquid
injection.
[0062] Further, since the air cell C1 includes the plural liquid
injection devices 32 each being located at a position vertically
separate from the liquid junction prevention portions 51, a liquid
junction between the electrode structures (the single cells) 1 via
the electrolyte liquid on the liquid supply unit 3 side can be
prevented at the time of and after injecting the electrolyte
liquid.
[0063] FIG. 3A to FIG. 11C are views for explaining air cells C2 to
C9 according to the first to eighth modified examples of the first
embodiment of the present invention. It should be noted that the
same elements as those of the air cell C1 are indicated by the same
reference numerals in the respective modified examples, and
specific explanations thereof are omitted as appropriate.
[0064] An air cell C2 according to the first modified example shown
in FIG. 3A and FIG. 3B includes, on the upper surface of the
electrode housing portion 2, the liquid injection holes 22
corresponding to the respective electrode structures 1, and liquid
junction prevention portions 52 each having a protruding structure
formed into a step and being located on one side of each liquid
injection hole 22. The liquid supply unit 3 includes the storage
tank 31 and a supply head 34 provided with the plural liquid
injection devices 32. The supply head 34 is connected to the
storage tank 31 via the pipe 35 and can be lifted up and down with
respect to the electrode housing portion 2.
[0065] In the air cell C2 configured as described above, the
electrolyte liquid is injected into the respective electrode
structures 1 by the liquid supply unit 3. The electrolyte liquid
may be injected while the supply head 34 is in contact with the
liquid junction prevention portions 52. The air cell C2 can
reliably prevent a liquid junction between the electrode structures
(the single cells) 1 via the electrolyte liquid in the same manner
as the air cell C1. An air cell C3 according to the second modified
example shown in FIG. 4A includes a plurality of liquid junction
prevention portions 53 each having surfaces inclined downward to
the liquid injection holes 22 or having a step. In particular, as
shown in FIG. 4B, each of the liquid junction prevention portions
53 has a triangular cross-section and has surfaces inclined
downward to the liquid injection holes 22.
[0066] The air cell C3 can ensure smooth and rapid injection of the
electrolyte liquid into the liquid injection holes 22 and shorten
the startup time in a manner such that the inclined surfaces of the
liquid junction prevention portions 53 serve as a guide at the time
of injecting the electrolyte liquid, so as to achieve the same
functions and effects as the air cell C1. The inclined surfaces of
the liquid junction prevention portions 53 contribute to avoiding
the remains of the electrolyte liquid and thereby reliably
preventing a liquid junction.
[0067] An air cell C4 according to the third modified example shown
in FIG. 5A includes a plurality of liquid junction prevention
portions 54 each having surfaces inclined downward to the liquid
injection holes 22 or having a step. In particular, as shown in
FIG. 5B, each of the liquid junction prevention portions 54 has a
trapezoidal cross-section and has surfaces inclined downward to the
liquid injection holes 22.
[0068] The air cell C4 can ensure smooth and rapid injection of the
electrolyte liquid into the liquid injection holes 22 and shorten
the startup time in a manner such that the inclined surfaces of the
liquid junction prevention portions 53 serve as a guide at the time
of injecting the electrolyte liquid, so as to achieve the same
functions and effects as the air cell C1. In addition, since the
upper surfaces of the respective liquid junction prevention
portions 54 are flat, the liquid supply unit 3 comes into contact
with the liquid junction prevention portions 54 when the
electrolyte liquid is injected so that the liquid supply unit 3 can
be positioned appropriately.
[0069] FIGS. 6A, 6B and 6C show liquid junction prevention portions
55, 56 and 57, respectively, each having surfaces inclined downward
to the liquid injection holes 22 or having steps. The liquid
junction prevention portion 55 shown in FIG. 6A has a
cross-sectional shape having downward steps towards the liquid
injection hole 22. The liquid junction prevention portion 56 shown
in FIG. 6B has a cross-sectional shape having a concave curved
surface inclined downward to the liquid injection hole 22. The
liquid junction prevention portion 57 shown in FIG. 6C has a
cross-sectional shape having a convex curved surface inclined
downward to the liquid injection hole 22. The respective liquid
junction prevention portions 55, 56 and 57 can achieve the same
effects as the liquid junction prevention portion 51 of the air
cell C1.
[0070] An air cell C5 according to the fourth modified example
shown in FIG. 7A includes a plurality of liquid junction prevention
portions 58 each including a plurality of projections 58A located
at predetermined intervals in the arrangement direction of the
electrode structures 1. In particular, the respective liquid
junction prevention portions 58 include the plural projections 58A
having the same height.
[0071] The air cell C5 can achieve the same functions and effects
as the air cell C1. In particular, the air cell C5 can secure the
state of preventing a liquid junction immediately after the
electrolyte liquid is injected, so as to achieve an improved liquid
junction preventing function. Alternately, the liquid junction
prevention portions 58 each include the plural projections 58A
having different heights.
[0072] The air cell C5 may further include sensors S between the
respective projections 58A, as shown in FIG. 7B. According to this
configuration, even when the electrolyte liquid flowing from the
liquid injection devices 32 flows over the projections 58A closest
to the liquid injection holes 22, the sensors S can detect the
flowing electrolyte liquid so as to close the switching body
41.
[0073] In an air cell C6 according to the fifth modified example
shown in FIG. 8A and FIG. 8B, the liquid injection device 32 of the
liquid supply unit 3 includes a switching body 42 instead of the
switching body 41 (the switching valve) of the air cell C1. The
switching body 42 is placed to allow the electrolyte liquid to flow
into the plural liquid injection holes 22. The switching body 42 of
this modified example is a partitioning plate. The air cell C6
opens the switching body 42 so as to allow the electrolyte liquid
to immediately flow onto the upper surface of the electrode housing
portion 2 and thereby inject the electrolyte liquid into the plural
electrode structures 1. Here, the electrolyte liquid may fall on
and cover the middle liquid junction prevention portion 51.
[0074] The air cell C6 can greatly shorten the time interval
between the injection of the electrolyte liquid and the startup.
The liquid junction prevention portions 51 can reliably prevent a
liquid junction between the electrode structures (the single cells)
1 via the electrolyte liquid after the injection of the electrolyte
liquid.
[0075] An air cell C7 according to the sixth modified example shown
in FIG. 9A and FIG. 9B includes water-repellent portions 61a having
water repellency provided at least on peripheral surfaces of the
respective liquid injection devices 32. The water-repellent
portions 61a are formed, for example, in a manner such that an
arbitrary water-repellent agent is applied to the peripheral
surfaces of the respective liquid injection devices 32. The contact
angle of each water-repellent portion 61a with respect to the
electrolyte liquid (namely, water or an electrolysis solution) is
at least 50 degrees or greater, preferably 80 degrees or
greater.
[0076] The air cell C7 can achieve the same functions and effects
as the air cell C1 and also prevent the electrolyte liquid from
adhering to the peripheries of the respective liquid injection
devices 32 due to the water-repellent portions 61a. Accordingly,
even in a state where the storage tank 31 is in contact with the
liquid junction prevention portions 51 as shown in FIG. 9A, a
liquid junction between the electrode structures (the single cells)
1 via the electrolyte liquid on the storage tank 31 side can be
prevented.
[0077] An air cell C8 according to the seventh modified example
shown in FIGS. 10A, 10B and 10C includes water-repellent portions
61b having water repellency provided at least on surfaces of top
portions of the respective liquid junction prevention portions 52.
The air cell C8 can achieve the same functions and effects as the
air cell C1 and also prevent the electrolyte liquid from remaining
on the top portions of the respective liquid junction prevention
portions 52 due to the water-repellent portions 61b. Accordingly,
the air cell C8 can further improve the liquid junction preventing
function due to the liquid junction prevention portions 52.
[0078] An air cell C9 according to the eighth modified example
shown in FIG. 11A and FIG. 11B includes hydrophilic portions 62a
having hydrophilicity provided on peripheries of the openings of
the respective liquid injection holes 22. The hydrophilic portions
62a are formed, for example, in a manner such that an arbitrary
hydrophilic agent is applied to the peripheries of the openings of
the respective liquid injection holes 22. The contact angle of each
hydrophilic portion 62a with respect to the electrolyte liquid
(namely, water or an electrolysis solution) is at least less than
80 degrees, preferably less than 50 degrees.
[0079] The air cell C9 can achieve the same functions and effects
as the air cell C1 and also allow the electrolyte liquid to easily
flow into the respective liquid injection holes 22 due to the
hydrophilic portions 62a so as to further shorten the startup time
in association with an increase of the liquid injection rate.
[0080] In addition to the hydrophilic portions 62a serving as
hydrophilic regions provided on the peripheries of the openings of
the respective liquid injection holes 22, the air cell C9 may
further include water-repellent portions 61c serving as
water-repellent regions on the outer sides of the hydrophilic
regions (namely, the hydrophilic portions 62a).
[0081] The air cell C9 can not only increase the liquid injection
rate and further shorten the startup time due to the hydrophilic
portions 62a but also prevent the electrolyte liquid from remaining
on the peripheries of the respective liquid injection holes 22 due
to the water-repellent portions 61c after the injection of the
electrolyte liquid. Accordingly, a liquid junction between the
electrode structures (the single cells) 1 via the electrolyte
liquid can be prevented.
Second Embodiment
[0082] In the present embodiment, the same elements as those of the
air cell C1 are indicated by the same reference numerals, and
specific explanations thereof are omitted as appropriate. An air
cell C10 shown in FIG. 12A and FIG. 12B includes the plural
electrode structures 1, the electrode housing portion 2 having a
plurality of housing compartments individually housing the plural
electrode structures 1, and the liquid supply unit 3 for supplying
the electrolyte liquid to the plural electrode structures 1, each
electrode structure 1 including the air electrode 11, the metal
negative electrode 12 and the filling chamber 13 for the
electrolyte liquid interposed between the respective
electrodes.
[0083] The electrode housing portion 2 includes, at the upper
portion thereof, a plurality of water-repellent portions 61d having
water repellency, instead of the plural liquid junction prevention
portions 51. The respective water-repellent portions 61d are
located between the liquid injection holes 22 adjacent to each
other.
[0084] The water-repellent portions 61d are each formed in a manner
such that an arbitrary water-repellent agent is applied to a
portion between the liquid injection holes 22 adjacent to each
other on the upper surface of the electrode housing portion 2. The
contact angle of each water-repellent portion 61d with respect to
the electrolyte liquid (namely, water or an electrolysis solution)
is at least 50 degrees or greater, preferably 80 degrees or
greater. The electrode housing portion 2 is further provided, at
the upper portion thereof, with water-repellent portions 61d placed
towards the end portions in the arrangement direction with respect
to the liquid injection holes 22 for injecting the electrolyte
liquid into the filling chambers 13 of the electrode structures 1
located at the end portions in the arrangement direction. In other
words, the water-repellent portions 61d are also placed on both
sides of each liquid injection hole 22.
[0085] The air cell C10 can remove the electrolyte liquid from the
respective water-repellent portions 61d so as to prevent the
electrolyte liquid remaining on the upper portion of the electrode
housing portion 2 from connecting the liquid injection holes 22
adjacent to each other. Accordingly, the air cell C10 can reliably
prevent a liquid junction between the electrode structures (the
single cells) 1 adjacent to each other, namely, a short circuit via
the electrolyte liquid. Therefore, the air cell C10 can be applied
appropriately to an air cell with high output power and high
capacity using an electrolysis solution having high resistance,
such as a strong alkaline electrolysis solution, in which any
liquid junction should be prevented. The air cell C10 is thus
remarkably suitable for an onboard power supply for a vehicle or
the like which is required to have high output power and high
capacity.
[0086] Further, since the air cell C10 includes the liquid
injection devices 32 each being located at a position vertically
separate from the electrode housing portion 2, a liquid junction
between the electrode structures (the single cells) 1 via the
electrolyte liquid on the liquid supply unit 3 side can be
prevented at the time of and after injecting the electrolyte
liquid.
[0087] FIG. 13A to FIG. 15B are views for explaining air cells C11
to C13 according to the first to third modified examples of the
second embodiment of the present invention. It should be noted that
the same elements as those of the air cell C10 are indicated by the
same reference numerals in the respective modified examples, and
specific explanations thereof are omitted as appropriate.
[0088] The air cell C11 according to the first modified example
shown in FIG. 13A and FIG. 13B includes, on the upper surface of
the electrode housing portion 2, the plural liquid injection holes
22 corresponding to the respective electrode structures 1, a
plurality of water-repellent portions 61e, and a plurality of
hydrophilic portions 62b provided on peripheries of the openings of
the respective liquid injection holes 22. Therefore, the electrode
housing portion 2 is provided, on the upper surface thereof, with
the water-repellent portions 61e and the hydrophilic portions 62b
including the liquid injection holes 22 alternately arranged.
[0089] The hydrophilic portions 62b are formed by the application
of an arbitrary hydrophilic agent. The contact angle of each
hydrophilic portion 62b with respect to the electrolyte liquid
(namely, water or an electrolysis solution) is at least less than
80 degrees, preferably less than 50 degrees.
[0090] The air cell C11 configured as described above can not only
achieve the same functions and effects for liquid junction
prevention as the air cell C10 due to the water-repellent portions
61e but also allow the electrolyte liquid to easily flow into the
respective liquid injection holes 22 due to the hydrophilic
portions 62b so as to further shorten the startup time in
association with an increase of the liquid injection rate.
[0091] In an air cell C12 according to the second modified example
shown in FIG. 14A and FIG. 14B, the liquid injection device 32 of
the liquid supply unit 3 provided in the air cell C11 includes the
switching body 42 instead of the switching body 41 (the switching
valve) of the air cell C11. The switching body 42 is placed to
allow the electrolyte liquid to flow into the plural liquid
injection holes 22. The switching body 42 of this modified example
is a partitioning plate. The electrode housing portion 2 is
provided with ribs 24 on both sides or on the periphery of the
upper surface thereof. The ribs 24 prevent the electrolyte liquid
from flowing out of the air cell C12 at the time of injecting the
electrolyte liquid.
[0092] The air cell C12 opens the switching body 42 so as to allow
the electrolyte liquid to immediately flow onto the upper surface
of the electrode housing portion 2 and thereby inject the
electrolyte liquid into the plural electrode structures 1.
Therefore, the air cell C12 can greatly shorten the time interval
between the injection of the electrolyte liquid and the startup.
The air cell C12 can remove the electrolyte liquid from the
water-repellent portions 61e after the injection of the electrolyte
liquid so as to prevent the electrolyte liquid from connecting the
liquid injection holes 22 adjacent to each other. Accordingly, the
air cell C12 can reliably prevent a liquid junction between the
electrode structures (the single cells) 1 via the electrolyte
liquid.
[0093] An air cell C13 according to the third modified example
shown in FIG. 15A and FIG. 15B includes, on the upper surface of
the electrode housing portion 2, the liquid injection holes 22, the
water-repellent portions 61e and the hydrophilic portions 62b, and
further includes the water-repellent portions 61a provided at least
on peripheral surfaces of the respective liquid injection devices
32. The electrode housing portion 2 is provided, on the upper
surface thereof, with ribs 25 in contact with the storage tank 31
of the liquid supply unit 3. The ribs 25 function to prevent the
electrolyte liquid from flowing out of the air cell C13 at the time
of injecting the electrolyte liquid as in the case of the air cell
C12, and function to position the liquid supply unit 3
appropriately.
[0094] The air cell C13 can achieve the same functions and effects
as the air cell C12 and also prevent the electrolyte liquid from
adhering to the peripheries of the respective liquid injection
devices 32 due to the water-repellent portions 61a on the storage
tank 31 side. Accordingly, the air cell C13 having a configuration
in which the storage tank 31 is in contact with the ribs 25, can
prevent a liquid junction between the electrode structures (the
single cells) 1 via the electrolyte liquid on the storage tank 31
side.
[0095] The air cell according to the present invention is not
limited to the first or second embodiment, and specific
configurations such as shapes, numbers and materials of the
respective elements can be modified as appropriate without
departing from the scope of the present invention. Although the
first embodiment exemplified the liquid junction prevention
portions having predetermined lengths such as ribs, other liquid
junction prevention portions formed, for example, in such a manner
as to surround the respective liquid injection holes may be
applicable. Although the second embodiment exemplified the
water-repellent portions having predetermined lengths, other
water-repellent portions provided, for example, in regions
surrounding the respective liquid injection holes may be
applicable. Further, the first to eighth modified examples of the
first embodiment and the first to third modified examples of the
second embodiment may be combined as appropriate.
[0096] The injection-type air cell according to the present
invention including a plurality of electrode structures arranged in
series, can reliably prevent a liquid junction between the
electrode structures via the electrolyte liquid. Thus, the air cell
can be applied to an air cell with high output power and high
capacity using a strong alkaline electrolysis solution, and is
remarkably suitable for an onboard power supply for a vehicle or
the like.
* * * * *