U.S. patent application number 13/394272 was filed with the patent office on 2012-06-28 for battery module.
Invention is credited to Toshiki Itoi, Hiroshi Takasaki, Shunsuke Yasui.
Application Number | 20120164490 13/394272 |
Document ID | / |
Family ID | 43758331 |
Filed Date | 2012-06-28 |
United States Patent
Application |
20120164490 |
Kind Code |
A1 |
Itoi; Toshiki ; et
al. |
June 28, 2012 |
BATTERY MODULE
Abstract
The case 20 housing a plurality of cells 100 is divided, by a
circuit board 30 provided at the same sides of the cells 100, into
a housing space 50 housing the cells 100 and an exhaust duct 60 for
releasing a gas from the vents 8a of the cells 100 to outside the
case 20. The vents 8a of the cells 100 communicate with the exhaust
duct 60 through openings 30a formed in the flat plate 30. The
exhaust duct 60 is divided into a first space 61 and a second space
62 by a partition 40 provided between the flat plate 30 and an
external plate 21 of the case 20. The first space 61 communicates
with the second space 62 through holes 40a formed in the partition
40.
Inventors: |
Itoi; Toshiki; (Nara,
JP) ; Yasui; Shunsuke; (Osaka, JP) ; Takasaki;
Hiroshi; (Osaka, JP) |
Family ID: |
43758331 |
Appl. No.: |
13/394272 |
Filed: |
July 21, 2010 |
PCT Filed: |
July 21, 2010 |
PCT NO: |
PCT/JP2010/004674 |
371 Date: |
March 5, 2012 |
Current U.S.
Class: |
429/7 ;
429/82 |
Current CPC
Class: |
H01M 2220/20 20130101;
H01M 10/6566 20150401; H01M 10/613 20150401; Y02E 60/10 20130101;
H01M 50/502 20210101; H01M 50/35 20210101; H01M 50/30 20210101;
H01M 2200/00 20130101; H01M 50/20 20210101; H01M 50/383 20210101;
H01M 50/213 20210101; H01M 10/643 20150401 |
Class at
Publication: |
429/7 ;
429/82 |
International
Class: |
H01M 2/12 20060101
H01M002/12 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 18, 2009 |
JP |
2009-216463 |
Claims
1. A battery module in which a plurality of cells are arranged and
housed in a case, wherein each of the cells has a vent through
which a gas generated in the cell is released to outside the cell,
the case is divided, by a flat plate provided at same sides of the
cells, into a housing space housing the cells and an exhaust duct
for releasing a gas from the vents of the cells to outside the
case, each of the vents of the cells communicates with the exhaust
duct through an opening formed in the flat plate, the exhaust duct
is divided into a first space and a second space by a partition
provided between the flat plate and an external plate or a bottom
of the case, the first space communicates with the second space
through a through hole formed in the partition, and a gas from the
vent of the cell is released to the first space through the opening
formed in the flat plate, is guided to the second space through the
through hole formed in the partition, and then is released to
outside the case.
2. A battery module of claim 1, wherein the flat plate is in close
contact with an end of each of the cells, and the housing space is
hermetically sealed by the flat plate.
3. The battery module of claim 1, wherein a volume of the first
space is adjusted such that when a gas at a high temperature
released from the vent of the cell to the first space by adiabatic
expansion is released from the first space to the second space, the
gas has a temperature reduced to a predetermined temperature or
lower.
4. The battery module of claim 3, wherein the predetermined
temperature is a temperature at which the gas released from the
vent of the cell does not react with oxygen.
5. The battery module of claim 4, wherein the cells are lithium ion
secondary batteries, and the predetermined temperature is
450.degree. C.
6. The battery module of claim 1, wherein the first space is
further divided into a plurality of subspaces each having a volume
adjusted to a predetermined volume.
7. The battery module of claim 6, wherein a volume of each of the
subspaces is adjusted such that when a gas at a high temperature
released from the vent of the cell to the subspace of the first
space by adiabatic expansion is released from the subspace to the
second space, the gas has a temperature reduced to a predetermined
temperature or lower.
8. The battery module of claim 3, wherein a volume of the second
space is adjusted such that when a gas released from the first
space to the second space by adiabatic expansion is released from
the second space to outside the case, the gas has a temperature
equal to or lower than a temperature at which no significant
problems occur even when the gas is released to outside the
case.
9. The battery module of claim 8, wherein the temperature at which
no significant problems occur even when the gas is released to
outside the case is 200.degree. C.
10. The battery module of claim 1, wherein the vent of each of the
cells is provided in a positive electrode projection of the cell,
and the positive electrode projection is inserted in the opening of
the flat plate.
11. The battery module of claim 1, wherein the flat plate is a
circuit board, the circuit board includes a connection plate to
which at least an electrode of each of the cells is connected, and
the electrodes of the cells connected to the connection plate are
connected in parallel.
12. The battery module of claim 1, wherein the flat plate is a
metal bus bar to which at least an electrode of each of the cells
is connected, and the electrodes of the cells connected to the
metal bus bar are connected in parallel.
13. The battery module of claim 12, wherein the case of each of the
cells constitutes another electrode of each of the cells, and the
metal bus bar is in close contact with an end of each of the cells
with an insulator interposed therebetween.
14. The battery module of claim 1, wherein the first space is
formed between the flat plate and the partition, and the second
space is formed between the partition and an external plate or a
bottom of the case.
15. A battery module in which a plurality of cells are arranged and
housed in a case, wherein each of the cells has a vent through
which a gas generated in the cell is released to outside the cell,
the case is divided, by a flat plate provided at same sides of the
cells, into a housing space housing the cells and a first exhaust
space for releasing a gas from the vent of the cell to outside the
case through a release outlet of the case, each of the vents of the
cells communicates with the first exhaust space through an opening
formed in the flat plate, an exhaust duct including a second
exhaust space having an aperture communicating with the release
outlet is in contact with the case, and a gas from the vents of the
cells is released to the first exhaust space through the opening
formed in the flat plate, is guided to the second exhaust space
through the aperture, and then is released to outside the case.
16. The battery module of claim 15, wherein a volume of the first
exhaust space is adjusted such that when a gas at a high
temperature released from the vent of the cell to the first exhaust
space by adiabatic expansion is released from the first exhaust
space to the second exhaust space, the gas has a temperature
reduced to a predetermined temperature or less.
17. The battery module of claim 16, wherein the predetermined
temperature is a temperature at which the gas released from the
vents of the cells does not react with oxygen.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to battery modules in each of
which a plurality of batteries are housed in a case, and more
particularly to a battery module including a release mechanism for
releasing a gas from a battery to outside the case with safety.
BACKGROUND ART
[0002] Battery packs in each of which a plurality of batteries are
housed in a case so as to output a predetermined voltage and have a
predetermined capacity are widely used as power sources for various
equipment and vehicles. For these batteries packs, a technique of
connecting general-purpose batteries in parallel or in series to
form modules of battery assemblies each outputting a predetermined
voltage and having a predetermined capacity and of variously
combining such battery modules to cope with various applications.
This module technique enables reduction in size and weight of
battery modules by enhancing performance of batteries housed in
battery modules, and therefore, has advantages such as improved
workability in packaging battery packs and high flexibility in
installing battery modules in limited space of vehicles or the
like.
[0003] On the other hand, as the performance of batteries housed in
battery modules has been enhanced, it has become more and more
important to increase the safety of batteries modules as groups of
batteries as well as the safety of batteries themselves. In
particular, in a situation where a gas is generated by heat due to,
for example, an internal short circuit in a battery and a safety
valve actuates to release a high-temperature gas to outside the
battery, when adjacent batteries are exposed to this
high-temperature gas, normal batteries might also be affected,
resulting in the possibility of a secondary degradation influenced
by the abnormal battery.
[0004] To solve this problem, Patent Document 1 shows a power
source device including a release mechanism in which a case housing
a plurality of batteries is divided by a partition into a battery
space housing the batteries and a release space through which a
high-temperature gas from the batteries is released and in which
openings of safety valves of the batteries communicate with an
exhaust room. This configuration of the release mechanism allows a
high-temperature gas from the safety valves of the batteries to
flow into the exhaust space while preventing the high-temperature
gas from flowing into the battery space, and to be released to
outside the case through an outlet of the case. In this manner, it
is possible to prevent adjacent batteries from being exposed to a
high-temperature gas from an abnormal battery, thereby reducing a
harmful influence on normal batteries.
CITATION LIST
Patent Document
[0005] Japanese Patent Publication No. 2007-27011
SUMMARY OF THE INVENTION
Technical Problem
[0006] The release mechanism shown in Patent Document 1 provides a
hermetically sealed structure with the exhaust space, thereby
preventing a gas which has flown into the release space through an
opening of a battery from flowing into the battery space again. For
this reason, this release mechanism is advantageous in preventing a
secondary degradation of normal batteries.
[0007] However, a gas which has flown into the exhaust space can be
at a high temperature of 1000.degree. C. or more in some cases, and
might react with oxygen to cause combustion. In this case, the
exhaust space is exposed to a high temperature, and the batteries
housed in the battery space still have the possibility of being
affected by the high temperature.
[0008] It is therefore a major object of the present disclosure to
provide a safe battery module capable of releasing a
high-temperature gas from an abnormal battery to outside a case
without an influence on other normal batteries.
Solution to the Problem
[0009] To achieve the above object, the present disclosure employs
a configuration in which a case housing a plurality of cells is
divided by a partition into two spaces: a housing space housing the
cells and an exhaust duct for releasing a gas from the cells and in
which the exhaust duct is further divided by a partition into two
spaces. Openings through which a gas generated in the cells is
released communicate with a first space, and the first space
communicates with a second space through a through hole formed in
the partition.
[0010] With this configuration, a gas from the vents of the cells
is adiabatically expanded in the first space to have its
temperature reduced to a temperature at which the gas does not
cause combustion, and then is adiabatically expanded in the second
space to have its temperature reduced to a temperature a
temperature at which no significant problems occur even when the
gas is released to outside the case. Accordingly, a
high-temperature gas from an abnormal battery can be released to
outside the case with safety without an influence on other normal
batteries. As a result, a safe battery module can be achieved.
[0011] In other words, the volume of the first space is adjusted
such that when a gas at a high temperature released from the vent
of the cell to the first space by adiabatic expansion is released
from the first space to the second space, this gas has a
temperature equal to or lower than a temperature at which the gas
does not cause combustion. The volume of the second space is
adjusted such that when a gas released from the first space to the
second space by adiabatic expansion is released from the second
space to outside the case, this gas has a temperature equal to or
lower than a temperature at which no significant problems occur
even when the gas is released to outside the case.
[0012] A battery module in an aspect of the present disclosure is a
battery module in which a plurality of cells are arranged and
housed in a case. Each of the cells has a vent through which a gas
generated in the cell is released to outside the cell. The case is
divided, by a flat plate provided at same sides of the cells, into
a housing space housing the cells and an exhaust duct for releasing
a gas from the vents of the cells to outside the case. Each of the
vents of the cells communicates with the exhaust duct through an
opening formed in the flat plate. The exhaust duct is divided into
a first space and a second space by a partition provided between
the flat plate and an external plate or a bottom of the case. The
first space communicates with the second space through a through
hole formed in the partition. A gas from the vents of the cells is
released to the first space through the opening formed in the flat
plate, is guided to the second space through the through hole
formed in the partition, and then is released to outside the
case.
[0013] In a preferred embodiment, the flat plate separating the
housing space and the exhaust duct from each other is a circuit
board, and the circuit board includes a connection plate on which
at least electrodes of the cells at one side are connected in
parallel. Alternatively, the flat plate separating the housing
space and the exhaust duct from each other may be a metal bus bar
on which at least electrodes of the cells at one side are connected
in parallel.
[0014] With these configurations, the flat plate provided to the
same sides of the cells can additionally have a function of
electrically connecting the cells, as well as a function of
separating the housing space and the exhaust duct from each other.
As a result, the size of the battery module can be reduced.
Advantages of the Invention
[0015] According to the present disclosure, a high-temperature gas
from an abnormal battery can be released to outside a case without
an influence on other normal batteries. As a result, a battery
module with a high degree of safety can be obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a cross-sectional view schematically illustrating
a configuration of a battery for use in a battery module according
to a first embodiment of the present disclosure.
[0017] FIG. 2 is a cross-sectional view schematically illustrating
a configuration of the battery module of the first embodiment.
[0018] FIG. 3 is an enlarged cross-sectional view illustrating a
portion near an end of a cell to which a flat plate is
provided.
[0019] FIG. 4 is a partial cross-sectional view showing a
positional relationship between the cell and the flat plate in a
case where a vent of the cell is formed in a side of a projection
of a positive electrode terminal.
[0020] FIGS. 5(a)-5(c) are partial cross-sectional views each
showing a path of a gas released from vents of cells.
[0021] FIG. 6 is a cross-sectional view schematically illustrating
a configuration of a battery module 200 according to a variation of
the first embodiment.
[0022] FIGS. 7(a) and 7(b) are views illustrating a connection
structure among electrodes of cells, FIG. 7(a) is a disassembled
perspective view, and FIG. 7(b) is an enlarged cross-sectional view
illustrating a portion near positive electrode terminals of the
cells.
[0023] FIG. 8 is a perspective view illustrating a battery assembly
according to a second embodiment of the present disclosure.
[0024] FIG. 9 is a disassembled perspective view illustrating the
battery assembly of the second embodiment.
[0025] FIGS. 10(a) and 10(b) are enlarged views illustrating a
region XA and a region XB, respectively, shown in FIG. 9.
[0026] FIG. 11 shows plan views illustrating a negative electrode
bus bar, an insulating plate, and a positive electrode bus bar,
respectively, constituting a connection group.
[0027] FIG. 12 is a partial cross-sectional view in which adjacent
cells are connected in parallel.
[0028] FIG. 13 is a perspective view illustrating a configuration
of a group of battery assemblies in each of which cells are
connected in parallel.
[0029] FIG. 14 is a partial cross-sectional view illustrating a
connection structure between two cells and taken along the line
XIV-XIV in FIG. 13.
[0030] FIG. 15 is a disassembled perspective view illustrating a
battery module according to a specific example of the present
disclosure.
[0031] FIG. 16 is a perspective view illustrating the battery
module of the specific example.
[0032] FIGS. 17(a) and 17(b) show a structure of a partition, FIG.
17(a) is a perspective view, and FIG. 17(b) is a plan view.
[0033] FIGS. 18(a) and 18(b) show a structure of an intermediate
panel, FIG. 18(a) is a perspective view, and FIG. 18(b) is a plan
view.
[0034] FIG. 19 is a cross-sectional view taken along the direction
in which the battery assemblies of a battery module are connected
in series.
[0035] FIG. 20 is a cross-sectional view schematically illustrating
a configuration of a battery module according to a third
embodiment.
[0036] FIG. 21 is a plan view illustrating a variation of the
battery module of the third embodiment.
[0037] FIG. 22 is a perspective view illustrating a configuration
of a battery pack in which a plurality of battery modules are
arranged in parallel.
[0038] FIG. 23(a) is a cross-sectional perspective view
illustrating a configuration of a battery module, and FIG. 23(b) is
a partial cross-sectional view of the battery module.
[0039] FIG. 24 is a perspective view in which a first exhaust duct
and a second exhaust duct are in contact with one battery
module.
[0040] FIG. 25 is a disassembled perspective view illustrating the
structure shown in FIG. 24.
DESCRIPTION OF EMBODIMENTS
[0041] Embodiments of the present disclosure will be described
hereinafter with reference to the drawings. The present disclosure
is not limited to the following embodiments. Various changes and
modifications may be made without departing from the scope of the
present invention, and the following embodiments may be combined as
necessary.
First Embodiment
[0042] FIG. 1 is a cross-sectional view schematically illustrating
a configuration of a battery 100 to be used in a battery module
according to a first embodiment of the present disclosure. A
battery to be used in the battery module of the present disclosure
may be a battery which can be used alone as a power source for
mobile electronic equipment such as a laptop computer (and a
battery to be used in a battery module will be referred to as a
"cell" hereinafter). In this case, high-performance general-purpose
battery can be used as a cell of a battery module, and thus,
performance of the battery module can be more easily enhanced at
lower cost.
[0043] As a cell 100 to be used in a battery module according to
the present disclosure, a cylindrical lithium ion secondary battery
as illustrated in FIG. 1 may be employed, for example. This lithium
ion secondary battery has a general structure, and has a safety
mechanism which releases gas to outside the battery when the
pressure in the battery increases due to occurrence of, for
example, an internal short circuit. The structure of the cell 100
will be specifically described with reference to FIG. 1.
[0044] As illustrated in FIG. 1, an electrode group 4 in which a
positive electrode 1 and a negative electrode 2 are wound with a
separator 3 interposed therebetween is housed in a battery case 7
together with a nonaqueous electrolyte. Insulating plates 9 and 10
are respectively placed on the top and bottom of the electrode
group 4. The positive electrode 1 is joined to a filter 12 with a
positive electrode lead 5 interposed therebetween. The negative
electrode 2 is joined to the bottom of the battery case 7 also
serving as a negative electrode terminal, with a negative electrode
lead 6 interposed therebetween.
[0045] The filter 12 is connected to an inner cap 13 which has a
projection joined to a metal safety valve 14. The valve 14 is
connected to a terminal plate 8 also serving as a positive
electrode terminal. The terminal plate 8, the valve 14, the inner
cap 13, and the filter 12 serve as a unit, and seal an opening of
the battery case 7 with a gasket 11 interposed therebetween.
[0046] When an internal short circuit, for example, occurs in the
cell 100 to increase the pressure in the cell 100, the valve 14
bends toward the terminal plate 8. Then, when the inner cap 13 is
disconnected from the valve 14, a current path is shut off.
Thereafter, when the pressure in the cell 100 further increases,
the valve 14 is broken. Accordingly, a gas generated in the cell
100 is released to the outside through a through hole 12a in the
filter 12, a through hole 13a in the inner cap 13, the crack in the
valve 14, and a vent (opening portion) 8a in the terminal plate 8
in this order.
[0047] The safety mechanism for releasing a gas generated in the
cell 100 to the outside is not limited to the structure illustrated
in FIG. 1, and may have other structures.
[0048] FIG. 2 is a cross-sectional view schematically illustrating
a structure of a battery module 200 according to this
embodiment.
[0049] As illustrated in FIG. 2, a plurality of cells 100 are
arranged, and housed in a case 20. The cells 100 are fixed at
positions restricted by ribs 24 formed in the bottom 23 of the case
20. As illustrated in FIG. 1, each of the cells 100 includes the
vent 8a for releasing a gas generated in the cell 100 to outside
the cell 100.
[0050] The case 20 is divided into a housing space 50 housing a
plurality of cells 100 and an exhaust duct 60 for releasing a gas
from the vents 8a of the cells 100 to outside the case 20, by a
flat plate 30 disposed at the same sides (toward the positive
electrode terminals 8 in this embodiment) of the cells 100. The
vents 8a of the cells 100 communicate with the exhaust duct 60
through openings 30a formed in the flat plate 30.
[0051] In the present disclosure, the exhaust duct 60 is divided,
by a partition 40 placed between the flat plate 30 and an external
plate (lid) 21 of the case 20, into a first space 61 defined
between the partition 40 and the flat plate 30 and a second space
62 defined between the partition 40 and the external plate 21 of
the case 20. The first space 61 communicates with the second space
62 through a through hole 40a formed in the partition 40.
[0052] The exhaust duct thus configured allows a gas from the vents
8a of the cells 100 to be released to the first space 61 through
the openings 30a formed in the flat plate 30, guided to the second
space 62 through the through holes 40a in the partition 40, and
then released to outside the case 20 through a release outlet 22
provided in the case 20.
[0053] The flat plate 30 is in close contact with the same sides
(i.e., toward the positive electrode terminals 8 in this
embodiment) of the cells 100, and thus, the housing space 50 is
hermetically sealed by the flat plate 30. Accordingly, a gas
released to the first space 61 from the vents 8a of the cells 100
through the openings 30a of the flat plate 30 does not return to
the housing space 50 again.
[0054] FIG. 3 is an enlarged cross-sectional view illustrating a
portion near an end of a cell 100 to which the flat plate 30 is
provided. As illustrated in FIG. 3, in a state where the projection
of the positive electrode terminal 8 is inserted in the opening 30a
of the flat plate 30, a shoulder 7a of the battery case 7 and the
flat plate 30 are in close contact with each other with the elastic
member 31 interposed therebetween. Accordingly, a gas released from
the vent 8a formed in the projection of the positive electrode
terminal 8 does not return to the housing space again because the
housing space of the cell 100 is hermetically sealed by the flat
plate 30. The elastic member 31 may be adhesive. In this case, the
cell 100 can be held by the flat plate 30. The flat plate 30 may be
in direct contact with the shoulder 7a of the battery case 7 with
the elastic member 31 not interposed therebetween.
[0055] FIG. 4 is a partial cross-sectional view showing a
positional relationship between the cell 100 and the flat plate 30
in a case where a vent 8a of the cell 100 is formed in a side of
the projection of the positive electrode terminal 8. In this case,
the opening 30a formed in the flat plate 30 has a ring shape, and
thus, the battery case 7 and the flat plate 30 can be in close
contact with each other even on a flat portion of the projection of
the positive electrode terminal 8. This configuration allows the
elastic member to be adhesive, thereby further enhancing the
function of holding the cell 100.
[0056] The "flat plate 30" herein is not necessarily flat, and may
be a plate having unevenness according to the shape of the battery
case 7, for example, as long as the plate is flat as a whole.
[0057] The state of being "hermetically sealed" herein does not
necessarily mean a state of being completely sealed, and includes a
sealed state in which a negligible amount of gas returns from the
exhaust duct 60 to the housing space 50.
[0058] Next, advantages obtained by dividing the exhaust duct 60 of
the present disclosure into the first space 61 and the second space
62 will be described.
[0059] A gas released from the vents 8a of the cells 100 to the
exhaust duct 60 is adiabatically expanded in the exhaust duct 60,
thereby causing a decrease in temperature of the gas. However,
since the gas released from the vents 8a of the cells 100 can be at
a temperature of 1000.degree. C. or more in some cases, if the
temperature of the adiabatically expanded gas does not decrease to
a temperature at which the gas does not react with oxygen, the gas
might react with ambient oxygen to cause combustion.
[0060] The gas temperature decrease due to adiabatic expansion
depends on the capacity of the exhaust duct. Since the gas released
to the exhaust duct is released to outside the case 20 while
pushing oxygen in the exhaust duct out, the amount of a gas which
reacts with oxygen to cause combustion during adiabatic expansion
depends on the volume of the exhaust duct (i.e., the amount of
oxygen). Accordingly, to prevent a gas released from the vents 8a
of the cells 100 from reacting with oxygen to continuously cause
combustion, it is necessary to cause adiabatic expansion in an
exhaust duct whose volume is as small as possible so as to reduce
the gas temperature to a temperature at which the gas does not
react with oxygen. To satisfy this necessity, the volume of the
exhaust duct needs to be controlled near the vents 8a of the cells
100 through which a high-temperature gas is released.
[0061] The first space 61 of the present disclosure is provided to
achieve the control described above. The volume of the first space
61 is adjusted such that when a gas at a high temperature released
from the vent 8a of the cell 100 to the first space 61 by adiabatic
expansion is released from the first space 61 to the second space
62, this gas has a temperature equal to or lower than a temperature
at which the gas does not react with oxygen.
[0062] The volume of the first space 61 can be appropriately
adjusted in consideration of performance of the cells 100 to be
used, the type of an electrolyte (i.e., the type of a gas to be
generated). In addition, the volume of the first space 61 for
achieving the temperature described above may be obtained through a
simulation using a model of adiabatic expansion, or may be obtained
through various experiments. Specifically, as an example of a
simple experiment, the vent 8a of the cell 100 is formed to have a
space having a certain volume, and a release outlet from this space
to the atmosphere is provided. Then, a nail is driven in the
battery case 7 of the cell 100 to cause an internal short circuit
as a simulation, resulting in gushing of a high-temperature gas
from the vent 8a. By selecting the volume of the space, the gas
otherwise gushing from the release outlet with a spark and fire can
be changed into smoke in a state in which fire has been
extinguished. In this manner, the volume of the first space 61 can
be determined.
[0063] The first space 61 communicates with the second space 62
through the through holes 40a formed in the partition 40.
Accordingly, the location of the through holes 40a affects a path
through which a high-temperature gas from the vents 8a of the cells
100 flows from the first space 61 to the second space 62. In view
of this, the volume of the first space 61 may be further adjusted
in consideration of the location of the through holes 40a.
[0064] Specifically, although not shown, the space 61 is not open
but closed in the lateral direction in FIG. 5(a). Accordingly, as
illustrated in FIG. 5(a), in a case where the through holes 40a are
arranged at the same pitch as the cells 100, a path through which a
high-temperature gas from the vents 8a of the cells 100 flows from
the first space 61 to the second space 62 is a path indicated by
arrows in most part. Thus, the first space 61 is expected to be
substantially controlled by a space in the range indicated by A. In
addition, as illustrated in FIG. 5(b), in a case where the through
holes 40a are arranged at a pitch wider than that of the cells 100,
a path through which a high-temperature gas from the vents 8a of
the cells 100 flows from the first space 61 to the second space 62
is a path indicated by arrows in most part. Thus, the first space
61 is expected to be substantially controlled by a space in the
range indicated by B.
[0065] In this manner, the location of the through holes 40a can
substantially control the volume of the first space 61.
Alternatively, as illustrated in FIG. 5(c), the volume of the first
space 61 may be controlled by further dividing the first space into
a plurality of subspaces 63 by side walls 41.
[0066] The control of the first space 61 is not strictly defined.
Effective advantages of the present disclosure can be achieved by
dividing the exhaust duct 60 into the first space 61 and the second
space 62 to adjust the volume of the first space 61 communicating
with the vents 8a of the cells 100.
[0067] On the other hand, the volume of the second space 62 is
adjusted such that when a gas released from the first space 61 to
the second space 62 by adiabatic expansion is released from the
second space 62 to outside the case 20, the gas has a temperature
equal to or lower than a temperature at which no significant
problems occur even when the gas is released to outside the case.
Since the gas released from the space 61 to the second space 62 is
changed to be at a temperature at which the gas does not react with
oxygen in the first space 61, the possibility of combustion of the
gas is eliminated in the second space 62. Accordingly, unlike the
first space 61, the second space 62 does not need to have a volume
as small as possible for adiabatic expansion, and is allowed to
have a relatively large volume as compared to the first space. In
addition, each of the external plate 21 and the partition 40 may be
made of a material having a high thermal conductivity, such as
aluminium or iron. In this case, an advantage of a temperature
decrease by conduction of heat can be achieved in addition to an
advantage of a temperature decrease by adiabatic expansion.
[0068] In this embodiment, the exhaust duct 60 is divided into the
first space 61 and the second space 62. Alternatively, to control a
temperature decrease of a gas by adiabatic expansion, the exhaust
duct 60 may be divided into three or more spaces by a plurality of
partitions.
[0069] The second space 62 is not necessarily formed between the
partition 40 and the case 20. For example, the second space 62 may
be placed between the partition 40 and a second partition provided
between the partition 40 and the external plate 21. In this case,
the space formed between the second partition and the external
plate may be a flow path through which a refrigerant flows. This
configuration can more efficiently reduce the temperature of a gas
in the second space 62.
[0070] In this embodiment, the vents 8a of the cells 100 are formed
in projections (flat portions or sides) of the positive electrode
terminals 8, but may be formed in the bottoms of the battery case 7
serving as the negative electrode terminals. In this case, the flat
plate 30 is provided toward the negative electrode terminals of the
cells 100, and the exhaust duct 60 is formed between the flat plate
30 and the bottom of the case 20. The vents 8a formed in the
bottoms of the battery cases 7 communicate with the exhaust duct 60
through the openings 30a formed in the flat plate 30.
Variation of First Embodiment
[0071] As illustrated in FIG. 2, in the first embodiment, the
exhaust duct 60 is separated from the housing space 50 by a plate
disposed at the same sides (i.e., toward the positive electrode
terminals or the negative electrode terminals) of the cells 100.
This configuration is obtained by arranging the cells 100 in the
case 20 with the polarities of the cells 100 oriented in the same
direction.
[0072] FIG. 6 is a cross-sectional view schematically illustrating
a configuration of the battery module 200 according to a variation
of the first embodiment. As illustrated in FIG. 6, this variation
is different from the first embodiment in that the cells 100 are
arranged with their polarities alternately oriented in opposite
directions.
[0073] As illustrated in FIG. 6, the cells 100 are housed in the
case 20 in such a manner that the positions of the positive
electrode terminals 8 alternate between the top and the bottom,
specifically, the positive electrode terminal 8 of the cell 100a is
positioned at the top and the positive electrode terminal 8 of the
cell 100b adjacent to the cell 100a is positioned at the bottom. In
this variation, the vents 8a from which a gas generated in the
cells 100 is released are formed in the projections of the positive
electrode terminals 8.
[0074] The flat plate 30 separating the housing space 50 and the
exhaust duct 60 is disposed at each end of each of the cells 100,
resulting in that the exhaust duct 60 is formed as two exhaust
ducts 60a and 60b respectively located at the bottom and the top of
the case 20 and sandwiching the housing space 50. Each of the vents
8a of the cells 100 communicates with one of the exhaust ducts 60a
and 60b through the opening 30a formed in the flat plate 30.
[0075] The exhaust duct 60a at the top of the case 20 is divided,
by a partition 40 placed between the flat plate 30 and the external
plate 21 of the case 20, into a first space 61a formed between the
partition 40 and the flat plate 30 and a second space 62a formed
between the partition 40 and the external plate 21 of the case 20.
The first space 61a communicates with the second space 62a through
the through holes 40a formed in the partition 40.
[0076] In the same manner, the exhaust duct 60b at the bottom of
the case 20 is divided, by a partition 40 placed between the flat
plate 30 and the bottom 23 of the case 20, into a first space 61b
formed between the partition 40 and the flat plate 30 and a second
space 62b formed between the partition 40 and the bottom 23 of the
case 20. The first space 61b communicates with the second space 62b
through the through holes 40a formed in the partition 40.
[0077] In a manner similar to that in the first embodiment, a gas
is released from the vents 8a of the cells 100 to the first space
61a, 61b through the openings 30a formed in the flat plate 30, is
guided to the second space 62a, 62b through the through holes 40a
formed in the partition 40, and then is released to outside the
case 20 through the release outlet 22 provided in the case 20.
[0078] In this variation, advantages obtained by dividing each of
the exhaust ducts 60a and 60b into the first space 61a, 61b and the
second space 62a, 62b are similar to those in the first
embodiment.
[0079] In this variation, two exhaust ducts 60a and 60b are
provided. Accordingly, the height of the case 20 increases to cause
an increase in the volume of the battery module 200. However, since
the cells 100 are arranged with their polarities alternatively
oriented in opposite directions, the connection plate can be
advantageously formed to be in the shape of a simple plate in
connecting the cells 100 in series.
Second Embodiment
[0080] In the first embodiment, the housing space 50 housing the
cells 100 and the exhaust duct 60 for releasing a gas from the
vents 8a of the cells 100 are separated from each other by the flat
plate 30. The flat plate 30 may have a function of electrically
connecting the electrodes of the cells 100.
[0081] In this embodiment, this function of the flat plate 30 of
electrically connecting the electrodes of the cells 100 will be
described. The connection structure among the electrodes of the
cells 100 described in this embodiment does not limit the release
mechanism described in the first embodiment. In the following
description, description of the housing space 50 of the cells 100
and the exhaust duct 60 will not be repeated.
[0082] FIGS. 7(a) and 7(b) are views illustrating a connection
structure among the electrodes of the cells 100 connected in a line
(hereinafter referred to as a "battery assembly"). Specifically,
FIG. 7(a) is a disassembled perspective view, and FIG. 7(b) is an
enlarged cross-sectional view illustrating a portion near positive
electrode terminals 8 of the cells 100.
[0083] As illustrated in FIG. 7(a), a positive electrode connection
plate 70 and a negative electrode connection plate 73 are formed on
the surface of a circuit board 30, and openings 70a are formed in
the positive electrode connection plate 70. In addition, openings
30a are formed in the circuit board 30. Negative electrode
terminals of the cells 100 (i.e., the bottoms of the battery cases)
are connected in parallel by a negative electrode bus bar 81, and
are connected to the negative electrode connection plate 73 on the
circuit board 30 through a conductive part 72 extending from the
negative electrode bus bar 81. In this manner, the cells 100 are
connected in parallel by the positive electrode connection plate 70
and the negative electrode connection plate 73 formed on the
circuit board 30.
[0084] In addition, as illustrated in FIG. 7(b), projections of
positive electrode terminals 8 of the cells 100 are inserted in the
openings 30a of the circuit board 30 to be connected to the
positive electrode connection plate 70 formed on the circuit board
30. At this time, the circuit board 30 is brought into contact with
the battery cases with an elastic member 31 interposed
therebetween. The vents 8a of the cells 100 communicate with an
exhaust duct (not shown) through the openings 70a of the positive
electrode connection plate 70. In this manner, a gas from the vents
8a of the cells 100 is released to the exhaust duct through
openings 30a formed in the circuit board 30. In addition, since the
circuit board 30 hermetically seals a housing space (not shown) for
the cells 100, the gas released to the exhaust duct does not return
to the housing space again.
[0085] The flat plate 30 having the function of electrically
connecting the electrodes of the cells 100 is not necessarily a
circuit board made of an insulating member, and may be a connection
plate made of a metal member (hereinafter referred to as a "metal
bus bar").
[0086] The connection structure among the electrodes of the cells
100 using a metal bus bar will be described hereinafter with
reference to FIGS. 8-14.
[0087] FIG. 8 is a perspective view illustrating a battery assembly
300 according to this embodiment. FIG. 9 is a disassembled
perspective view illustrating the battery assembly 300. The battery
cases of the cells 100 are exposed in this embodiment. Accordingly,
in the cells 100, not only the bottom surfaces of the battery cases
but also side surfaces and top surfaces thereof can serve as
negative electrode terminals.
[0088] As illustrated in FIG. 9, the positive electrode bus bar 83
and the negative electrode bus bar 81 connecting the positive
electrodes and the negative electrodes of the cells 100 in parallel
are in contact with the battery cases with the insulating plate 82
interposed between of the battery case and the bus bars 83 and 81
at the side of the positive electrode terminals of the cells 100.
The positive electrode terminals 8 of the cells 100 are connected
to the positive electrode bus bar 83 through positive electrode
connection strips 84.
[0089] In this manner, a connection group 85 including the negative
electrode bus bar 81, the insulating plate 82, the positive
electrode bus bar 83, and the connection strips 84 is locally
placed at the side of the positive electrode terminals 8 of the
cells 100, thereby further reducing the size of the battery
assembly 300. In addition, the negative electrode bus bar 81 and
the positive electrode bus bar 83 have specific shapes, which will
be described later. With this configuration, when battery
assemblies 300 in each of which cells 100 are connected in parallel
are arranged to form a group of battery assemblies (see FIG. 13),
these battery assemblies 300 can be easily connected in series
using the connection groups 85.
[0090] Configuration of the connection group 85 will be described
in detail with reference to FIGS. 10-12. FIGS. 10(a) and 10(b) are
enlarged views illustrating a region XA and a region XB,
respectively, shown in FIG. 9. FIG. 11 shows plan views
illustrating the negative electrode bus bar 81, the insulating
plate 82, and the positive electrode bus bar 83, respectively,
constituting the connection group 85. FIG. 12 is a partial
cross-sectional view in which adjacent cells 100 are connected in
parallel.
[0091] The negative electrode bus bar 81 is, for example, a nickel
plate having a thickness of 0.2 mm, and is configured to be in
contact with the battery cases (i.e., the negative electrode
terminals) of the cells 100 constituting the battery assembly 300.
As illustrated in FIG. 10(a), this negative electrode bus bar 81
has a stepped portion 81b extending along the longitudinal
direction, and through holes 81a and negative electrode connection
strips 81c are arranged to be spaced from one another along the
longitudinal direction. As illustrated in FIG. 12, when the
negative electrode bus bar 81 is brought into contact with the
battery cases, the positive electrode terminals 8 of the cells 100
are exposed in the through holes 81a. The negative electrode
connection strips 81c are welded to the outer peripheries of the
battery cases to be fixed to the battery cases. The bottoms (i.e.,
the negative electrode terminals) of the battery cases of the cells
100 may be connected in parallel by another metal bus bar 88. In
this case, the cells 100 can also be fixed.
[0092] The positive electrode bus bar 83 is, for example, a copper
plate having a thickness of about 1 mm, and is provided on the
negative electrode bus bar 81 with the insulating plate 82
interposed therebetween. As illustrated in FIG. 11, the positive
electrode bus bar 83 and the insulating plate 82 respectively have
through holes 83a and 82a. The through holes 83a are spaced from
one another along the longitudinal direction, and the through holes
82a are also spaced from one another along the longitudinal
direction. The through holes 81a, 82a, and 83a of the negative
electrode bus bar 81, the insulating plate 82, and the positive
electrode bus bar 83 communicate with one another. In this manner,
as illustrated in FIG. 12, the positive electrode terminals 8 of
the cells 100 are exposed in the through holes 81a, 82a, and
83a.
[0093] Each of the positive electrode connection strips 84 is, for
example, a nickel plate having a thickness of 0.2 mm, and as
illustrated in FIG. 10(b), has a first connection strip 84a, a
second connection strip 84b, and a stepped portion 84c. The first
connection strip 84a and the second connection strip 84b sandwich
the stepped portion 84c, and have different heights. As illustrated
in FIG. 12, the first connection strips 84a are connected to the
positive electrode terminals 8 of the cells 100, and the second
connection strips 84b are connected to the upper surface of the
positive electrode bus bar 83. In this manner, the positive
electrode terminals 8 of the cells 100 are connected to the
positive electrode bus bar 83 through the positive electrode
connection strips 84.
[0094] Then, the connection structure among the electrodes in a
case where a plurality of battery assemblies 300 illustrated in
FIG. 8 are arranged to form a group of the battery assemblies will
be described.
[0095] FIG. 13 is a perspective view illustrating a configuration
of a group of four battery assemblies 300 in each of which 10 cells
100 are connected in parallel. FIG. 14 is a partial cross-sectional
view illustrating a connection structure between two cells 100 and
taken along the line XIV-XIV in FIG. 13.
[0096] As illustrated in FIG. 14, the negative electrode bus bar 81
and the positive electrode bus bar 83 are in contact with the
battery cases 7 of the cells 100 with the insulating plate 82
interposed therebetween. In this configuration, as illustrated in
FIG. 11, an end 83b of the positive electrode bus bar 83 in the
lateral direction and the stepped portion 81b of the negative
electrode bus bar 81 in the lateral direction project in opposite
directions with respect to a center line L connecting the centers
of the through holes 83a, 82a, and 81a. Accordingly, in adjacent
cells 100A and 100B illustrated in FIG. 14, the end 83b of the
positive electrode bus bar 83 in the cell 100A and the stepped
portion 81b of the negative electrode bus bar 81 in the cell 100B
overlap each other, thereby connecting the cell 100A and the cell
100B to each other in series.
[0097] (Specific Example of Battery Module)
[0098] A specific example of application of the configuration of
the battery module of this embodiment will be described with
reference to FIGS. 15-19.
[0099] FIG. 15 is a disassembled perspective view illustrating a
battery module of this specific example. FIG. 16 is a perspective
view illustrating the battery module.
[0100] As illustrated in FIG. 15, a temperature adjustment unit 90,
a battery assembly group 400, a resin intermediate panel 93, and a
metal (e.g., aluminium) partition 40 are housed in a resin case 20.
The top of the case 20 is covered with a metal (e.g., aluminium)
external plate (lid) 21. The front of the case 20 is covered with a
resin front panel 94.
[0101] In the battery assembly group 400, seven battery assemblies
300 each including 20 parallel-connected cells 100 are connected in
series. The cells 100 are series-parallel connected, i.e.,
connected in series in some places and in parallel in other places,
by the connection group 85 illustrated in FIG. 9. A positive
electrode terminal 87 of the battery assembly group 400 is
connected to one of the positive electrode bus bars 83 constituting
the battery assemblies 300 (see FIG. 12), and are connected to a
positive electrode terminal 96 for external connection provided on
the front panel 94. A negative electrode terminal 86 of the battery
assembly group 400 is connected to one of the negative electrode
bus bars constituting the battery assemblies 300 (see FIG. 12), and
are connected to a negative electrode terminal 95 for external
connection provided on the front panel 94.
[0102] FIGS. 17(a) and 17(b) show a structure of the partition 40.
Specifically, FIG. 17(a) is a perspective view, and FIG. 17(b) is a
plan view. The partition 40 is made of, for example, aluminium. As
illustrated in FIGS. 17(a) and 17(b), a plurality of through holes
40a are formed at positions corresponding to the positive electrode
terminals 8 of the cells 100. On the top surface of the partition
40, projections 40b are arranged in two lines.
[0103] FIGS. 18(a) and 18(b) show a structure of the intermediate
panel 93. Specifically, FIG. 18(a) is a perspective view, and FIG.
18(b) is a plan view. The intermediate panel 93 is made of, for
example, a resin, and is partitioned into four hollow portions 93a
along the parallel connection of the battery assemblies 300, as
illustrated in FIGS. 18 (a) and 18(b).
[0104] As illustrated in FIG. 15, the temperature adjustment unit
90 has holding portions 90a in which the cells 100 constituting the
battery assembly group 400 are inserted to be held. A flow path
though which a fluid flows is formed among the holding portions
90a, 90a, . . . . In addition, inlet and outlet tubes 91 and 92 for
supplying a fluid to the flow path are connected to the front panel
94 of the temperature adjustment unit 90, and are inserted in
through holes 98 and 99 formed in the front panel 94.
[0105] FIG. 19 is a cross-sectional view taken along the direction
in which the battery assemblies 300 of battery modules are
connected in series. As illustrated in FIG. 19, the cells 100 are
housed in the holding portions 90a of the temperature adjustment
unit 90, and have their temperatures adjusted by the fluid flowing
in a flow path 97. The case 20 is partitioned, by the connection
group 85 provided on the positive electrode terminals 8 of the
cells 100, into a housing space housing the cells 100 and an
exhaust duct 60 for releasing a gas from the vents 8a of the cells
100 to outside the case 20. The vents 8a of the cells 100
communicate with the exhaust duct 60 through the through holes 83a,
82a, and 81a of the negative electrode bus bar 81, the insulating
plate 82, and the positive electrode bus bar 83 constituting the
connection group 85.
[0106] The exhaust duct 60 is divided into a first space 61 and a
second space 62 by a partition 40 provided between the connection
group 85 and the external plate 21 of the case 20. The first space
61 communicates with the second space 62 through the through holes
40a formed in the partition 40. The first space 61 is divided into
a plurality of subspaces by hollow portions 93a formed in the
intermediate panel 93. In this manner, a gas from the vents 8a of
the cells 100 is released to the first space 61 (i.e., the
subspaces) through the through holes 83a, 82a, and 81a of the
connection group 85, and is guided to the second space 62 through
the through holes 40a formed in the partition 40, and then is
released to outside the case 20 through the release outlet 22
formed in the front panel 94.
Third Embodiment
[0107] In the first embodiment, although the exhaust duct 60 is
divided into the first space 61 and the second space 62 by the
partition 40, a gas released from the first space 61 to the second
space 62 has a temperature equal to or lower than a temperature at
which the gas does not react with oxygen, and thus, the possibility
of combustion of a gas is eliminated in the second space 62.
Accordingly, unlike the first space 61, the second space 62 does
not need to have a volume as small as possible for adiabatic
expansion, and is allowed to have a relatively large volume as
compared to the first space. In other words, an exhaust space
corresponding to the second space 62 does not need to be provided
in the case 20 housing a plurality of cells 100.
[0108] A battery module according to this embodiment employs a
configuration in which a first exhaust space (corresponding to the
first space 61) defined by a flat plate 30 placed at the same sides
of the cells 100 is provided in a case 20 and a second exhaust
space (corresponding to the second space 62) communicating with the
first exhaust space is provided to be in contact with the case
20.
[0109] In this embodiment, in a manner similar to that in the first
embodiment, the volume of the first exhaust space is adjusted such
that when a gas released from vent 8a of the cell 100 to the first
exhaust space by adiabatic expansion is released from the first
exhaust space to the second exhaust space, this gas has a
temperature equal to or lower than a temperature at which the gas
does not react with oxygen.
[0110] FIG. 20 is a cross-sectional view schematically illustrating
a configuration of a battery module 200 according to this
embodiment.
[0111] As illustrated in FIG. 20, a plurality of cells 100 are
arranged and housed in a case 20. As illustrated in FIG. 1, the
cells 100 have vents 8a through which a gas generated in the cells
100 is released to outside the cells 100.
[0112] The case 20 is divided, by a flat plate 30 provided at the
same sides of the cells 100, into a housing space 50 housing the
cells 100 and a first exhaust space 61c from which a gas from the
vents 8a of the cells 100 is released to outside the case 20
through a release outlet 22 provided in the case 20. The vents 8a
of the cells 100 communicate with the first exhaust space 61c
through openings 30a formed in the flat plate 30.
[0113] In this embodiment, an exhaust duct 65 including a second
exhaust space 62c having an aperture 66a communicating with the
release outlet 22 is in contact with the case 20. A gas from the
vents 8a of the cells 100 is released to the first exhaust space
61c through the openings 30a formed in the flat plate 30, is guided
to the second exhaust space 62c through the aperture 66a, and then
is released to outside the case 20 through a release outlet 66b
formed in the exhaust duct 65.
[0114] In this embodiment, the case 20 and the exhaust duct 65 may
be formed as an integrated unit. In this case, the battery module
200 includes the housing space 50, the first exhaust space 61c, and
the exhaust duct 65.
[0115] FIG. 21 is a plan view illustrating a variation of the
battery module shown in FIG. 20. In this variation, a plurality of
(four in FIG. 21) of battery modules 200 in each of which a
plurality of cells 100 are aligned are arranged in parallel. In
this case, instead of the exhaust duct 65 including the second
exhaust space 62c and provided for each of the battery modules 200,
an exhaust duct 65 including apertures 66a communicating with the
respective release outlets 22 of the battery modules 200 may be
provided to be in contact with the cases 20 of the battery modules
200. In this manner, the exhaust duct 65 shared by the battery
modules 200 can increase the substantial volume ratio of the
exhaust duct 65 to the exhaust spaces 61c of the battery modules
200. As a result, a temperature decrease due to adiabatic expansion
of a gas released from the first exhaust space 61c to the second
exhaust space 62c can be facilitated.
[0116] FIG. 22 is a perspective view illustrating a configuration
of a battery pack in which a plurality of (four in FIG. 22) battery
modules 200 including series-parallel connected cells 100 housed in
the case 20 as shown in FIG. 15 are arranged in parallel. The
battery modules 200 are in contact with the exhaust ducts 65
including the second exhaust spaces 62c. The first exhaust ducts 65
are in contact with second exhaust ducts 67 including third exhaust
spaces 67c.
[0117] FIG. 23(a) is a cross-sectional perspective view
illustrating a configuration of the battery module 200. FIG. 23(b)
is a partial cross-sectional view of the battery module 200.
[0118] FIG. 24 is a perspective view in which the first exhaust
duct 65 and the second exhaust duct 67 are in contact with one
battery module 200. FIG. 25 is a disassembled perspective view
illustrating the structure shown in FIG. 24.
[0119] As illustrated in FIGS. 23(b) and 25, the first exhaust duct
65 has a plurality of apertures 66a communicating with the first
exhaust space 61c of the battery module 200, and the second exhaust
duct 67 has a plurality of apertures 68a communicating with the
release outlet 66b of each of the first exhaust ducts 65.
[0120] As illustrated in FIG. 23(b), a gas from the vents 8a of the
cells 100 is released to the first exhaust space 61c, is guided to
the second exhaust space 62c through the apertures 66a, and then is
released to the outside through a release outlet 68b provided in
the second exhaust duct 67.
[0121] In this manner, a gas from the vents 8a of the cells 100 is
adiabatically expanded in the first exhaust space 61c, the second
exhaust space 62c, and the third exhaust space 67c in this order to
be released to outside the battery pack while having its
temperature reduced. As a result, a battery pack with a high degree
of safety can be obtained.
[0122] The present disclosure has been described based on the
foregoing preferred embodiments. These embodiments do not limit the
present disclosure, and may be variously changed or modified. For
example, in the above embodiments, the cells 100 are lithium ion
secondary batteries, but may be other secondary batteries (e.g.,
nickel-metal hydride batteries).
INDUSTRIAL APPLICABILITY
[0123] The present disclosure is useful for power sources for
driving automobiles, electric motorcycles, and electric play
equipment, for example.
DESCRIPTION OF REFERENCE CHARACTERS
[0124] 1 positive electrode [0125] 2 negative electrode [0126] 3
separator [0127] 4 electrode group [0128] 5 positive electrode lead
[0129] 6 negative electrode lead [0130] 7 battery case [0131] 7a
shoulder of battery case [0132] 8 positive electrode terminal
(terminal plate) [0133] 8a vent [0134] 9, 10 insulating plate
[0135] 11 gasket [0136] 12 filter [0137] 12a through hole [0138] 13
inner cap [0139] 13a through hole [0140] 14 valve [0141] 20 case
[0142] 21 external plate (lid) [0143] 22 release outlet [0144] 23
bottom of case [0145] 24 rib [0146] 30 flat plate (circuit board)
[0147] 30a opening [0148] 31 elastic member [0149] 40 partition
[0150] 40a through hole [0151] 40b projection [0152] 41 side wall
[0153] 50 housing space [0154] 60, 60a, 60b exhaust duct [0155] 61,
61a, 61b first space [0156] 61c first exhaust space [0157] 62c
second exhaust space [0158] 62, 62a, 62b second space [0159] 63
subspace [0160] 65 (first) exhaust duct [0161] 66a, 68a aperture
[0162] 66b, 68b release outlet [0163] 67 second exhaust duct [0164]
67c third exhaust space [0165] 70 positive electrode connection
plate [0166] 70a opening [0167] 72 conductive part [0168] 73
negative electrode connection plate [0169] 81 negative electrode
bus bar [0170] 81a, 82a, 83a through hole [0171] 81b stepped
portion [0172] 81c negative electrode connection strip [0173] 82
insulating plate [0174] 83 positive electrode bus bar [0175] 83b
end [0176] 84 positive electrode connection strip [0177] 84a first
connection strip [0178] 84b second connection strip [0179] 84c
stepped portion [0180] 85 connection group [0181] 86 negative
electrode terminal of battery assembly group [0182] 87 positive
electrode terminal of battery assembly group [0183] 90 temperature
adjustment unit [0184] 90a holding portion [0185] 91, 92 inlet and
outlet tubes [0186] 93 intermediate panel [0187] 93a hollow portion
[0188] 94 front panel [0189] 95 negative electrode terminal for
external connection [0190] 96 positive electrode terminal for
external connection [0191] 97 flow path [0192] 100 cell [0193] 200
battery module [0194] 300 battery assembly [0195] 400 battery
assembly group
* * * * *