WO2017119206A1

WO2017119206A1 - Battery module

Info

Publication number: WO2017119206A1
Application number: PCT/JP2016/084790
Authority: WO
Inventors: 和樹前田; 加藤　崇行; 浩生植田
Original assignee: 株式会社豊田自動織機
Priority date: 2016-01-08
Filing date: 2016-11-24
Publication date: 2017-07-13
Also published as: JP6561849B2; JP2017123309A

Abstract

This battery module (21) is provided with: an array (28) provided with a plurality of battery cells (23) which are arrayed in one direction (D), and a plurality of heat transfer plates (41) which are arrayed in the one direction, and which are disposed so as to be in contact with main surfaces (24c) of the battery cells, i.e. surfaces which intersect the one direction; and a bracket (25) which binds the array in a state in which pressure is being applied in the one direction. The heat transfer plates are provided with: first main body parts (42) which are in contact with the main surfaces; and second main body parts (43) which are respectively bent in a direction intersecting the main surfaces, from one end (43b) of each of the first main body parts, and which are in contact with a heat conduction member. Other ends (43a) of the second main body parts, said other ends being respectively located at the opposite side to each of the one ends, and the heat transfer plates which are adjacently disposed in the direction in which the second main body parts are bent from the first main body parts are separated by a distance (G) corresponding to the amount of movement of the heat transfer plates in the one direction caused by expansion of the battery cells.

Description

Battery module

One aspect of the present invention relates to a battery module.

There is known a battery pack in which a battery module in which a plurality of battery cells held in a battery holder are arranged is attached to a housing or the like. Patent Document 1 discloses a battery module that can improve heat dissipation by attaching a heat transfer plate to a battery holder and bringing the heat transfer plate into contact with a housing via a heat conductive member. In this battery module, an elastic member is disposed at an end in the arrangement direction of a plurality of battery cells arranged, and the plurality of battery cells and the elastic member are integrally restrained in a state of being pressed in the arrangement direction. .

JP 2015-156303 A

In the battery module configured as described above, an elastic member that absorbs the expansion of the battery cell in a certain range is arranged, and thus the heat transfer plate provided to come into contact with the battery cell moves in a certain range. Moreover, since the battery module of such a structure is fixed to a housing | casing in the state which pressed the heat conductive member, it deform | transforms in the pressing direction with the heat-transfer plate which contacts. For this reason, when there exists a deformation | transformation as mentioned above in the heat conductive member applicable to the movement destination part of a heat-transfer plate, a heat-transfer plate will not contact a heat conductive member and heat dissipation efficiency will fall.

Accordingly, an object of one aspect of the present invention is to provide a battery module that can suppress a decrease in heat dissipation efficiency even when the heat transfer plate moves in the arrangement direction of the battery cells due to the expansion of the battery cells. It is in.

A battery module according to one aspect of the present invention is a battery module that is attached to a housing via a heat conducting member, and a plurality of battery cells arranged in one direction and a surface intersecting in one direction of the battery cell. An array having a plurality of heat transfer plates arranged in one direction and in contact with a certain main surface, and a restraining portion that restrains the array in a state of being pressed in one direction. The heat transfer plate has a first main body portion that contacts the main surface, a second main body portion that bends in a direction intersecting the main surface from one end portion of the first main body portion, and contacts the heat conducting member. The other end portion of the two main body portions opposite to the one end portion and the heat transfer plate disposed adjacent to the first main body portion in the direction in which the second main body portion bends are disposed at a predetermined distance. The predetermined distance is a distance according to the amount of movement in one direction of the heat transfer plate due to the expansion of the battery cells.

In the battery module having this configuration, the end portion of the second main body portion opposite to the first main body portion and the heat transfer plate disposed adjacent to the first main body portion in the direction in which the second main body portion bends are provided. It is separated. Furthermore, the separation distance is a distance corresponding to the amount of movement in one direction of the heat transfer plate due to the expansion of the battery cells. The adjustment of the separation distance means that when one heat transfer plate moves due to the expansion of the battery cell, the one heat transfer plate and another heat transfer plate adjacent to the heat transfer plate in the moving direction are pressed. This means that the length of the overlapping portion in the moving direction with the heat conducting member deformed by the above is adjusted. Since the overlapping portion can be a portion where one heat transfer plate does not come into contact with the heat conducting member, in a battery module having a heat transfer plate in which the overlapping amount (that is, the separation distance) is appropriately adjusted, the heat dissipation efficiency is reduced. Can be suppressed.

In the battery module according to one aspect of the present invention, the length of the second body portion in one direction may be 1 to 10 times the thickness of the first body portion in one direction.

In the battery module according to one aspect of the present invention, the distance may be longer than the maximum amount of movement of the heat transfer plate due to the expansion of the battery cells.

According to the battery module of this configuration, even when the heat transfer plate moves due to the expansion of the battery cell, the heat transfer plate in which the other end of the second main body is arranged adjacent to the moving direction is arranged. It does not move to the position where it was done. In other words, even if the heat transfer plate moves due to the expansion of the battery cell, it does not move to the position of the heat conducting member deformed by the pressure of the heat transfer plate arranged adjacent to the moving direction. . Accordingly, a part of the second main body portion does not come into contact with the heat conducting member, and a state in which all of the second main body portion comes into contact with the heat conducting member can be maintained. As a result, it is possible to further suppress a decrease in heat dissipation efficiency.

The battery module according to one aspect of the present invention further includes an elastic member disposed at one end of the array body, and the restraining portion restrains the array body and the elastic member in a state of being pressed in one direction. May be.

In the battery module with this configuration, the expansion of the battery cell can be absorbed within a certain range.

In the battery module according to one aspect of the present invention, the length of the second main body portion in one direction may be made longer as the heat transfer plate is in contact with the battery cell arranged at a position far from the elastic member in one direction. .

In the battery module having this configuration, the heat transfer plate having a larger movement amount due to the expansion of the battery cell (that is, the heat transfer plate closer to the elastic member) has a shorter length in the moving direction of the second main body portion. Thereby, even when the heat transfer plate moves due to the expansion of the battery cell, there is a possibility of moving to the position of the heat conducting member deformed by the pressure of the heat transfer plate arranged adjacent to the moving direction. Can be lowered. As a result, it is possible to further suppress a decrease in heat dissipation efficiency.

According to one aspect of the present invention, even if the heat transfer plate moves in the battery cell arrangement direction due to the expansion of the battery cells, it is possible to suppress a decrease in heat dissipation efficiency.

FIG. 1 is a perspective view showing a battery pack including a battery module according to an embodiment. FIG. 2 is a side view showing the battery module according to the embodiment. FIG. 3 is an exploded perspective view showing the battery cell, battery holder, and heat transfer plate of FIG. FIG. 4 is a side view illustrating an arrangement state of the battery cell, the battery holder, and the heat transfer plate of FIG. 2. FIG. 5A is a side view showing one battery cell, a battery holder, and a heat transfer plate, and FIG. 5B is an enlarged side view showing a curved portion of the heat transfer plate. FIG. 6 is a side view showing the battery module of FIG. 2 attached to the side wall on which the heat conducting member is arranged. FIG. 7 is a side view showing a state where the battery module of FIG. 2 is attached to the side wall on which the heat conducting member is arranged. FIG. 8A is a side view showing a state before the heat transfer plate moves due to expansion of the battery cell, and FIG. 8B shows a state after the heat transfer plate moves due to expansion of the battery cell. FIG. FIG. 9A is an enlarged side view showing the vicinity of the elastic member included in the battery module of FIG. 2, and FIG. 9B is an enlarged view of the vicinity of the elastic member included in the battery module according to the modification. It is the side view shown.

Hereinafter, a battery pack 10 including a battery module 21 according to an embodiment will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

As shown in FIG. 1, the battery pack 10 has a housing 11. A plurality of battery modules 21 are accommodated in the housing 11. The casing 11 has a rectangular box shape, a rectangular flat plate-like bottom plate 12, a rectangular flat plate-like side wall 13 standing from the periphery of the bottom plate 12, and a rectangular flat plate shape that closes an opening surrounded by the side wall 13. The top plate 14 is provided.

As shown in FIG. 2, the battery module 21 includes a plurality of battery cells 23 (see FIG. 1), a pair of brackets (restraining portions) 25 and 25, an elastic member 47, bolts B and nuts N, and transmission. And a heat plate 41.

The battery cell 23 is a secondary battery such as a lithium ion secondary battery or a nickel hydride storage battery. As shown in FIG. 3, the battery cells 23 are juxtaposed in one direction D while being held by the battery holder 22. The battery holder 22 has a first covering portion 31, a second covering portion 32, a third covering portion 33, a fourth covering portion 34, and a pair of

leg portions

36 and 36.

The first covering portion 31 is a portion that is formed in a rectangular flat plate shape and covers the bottom 24 a of the battery cell 23. The second covering portion 32 and the third covering portion 33 are portions erected from both longitudinal ends of the first covering portion 31. The second covering portion 32 and the third covering portion 33 are formed in a rectangular flat plate shape and cover the side surface 24 b of the battery cell 23. The fourth covering portion 34 is a portion that is formed in a rectangular flat plate shape and covers a part of one main surface (surface orthogonal to the thickness direction) 24 c of the battery cell 23. The fourth covering portion 34 includes a first end portion 32 a (an end portion opposite to the end portion on which the first covering portion 31 is provided) in the longitudinal direction of the second covering portion 32 and a longitudinal direction of the third covering portion 33. Is connected to the first end 33a (the end opposite to the end where the first covering portion 31 is provided). The fourth covering portion 34 is arranged such that the thickness direction thereof coincides with the juxtaposed direction of the battery cells 23 and the longitudinal direction thereof coincides with the opposing direction of the second covering portion 32 and the third covering portion 33. A region surrounded by the first covering portion 31, the second covering portion 32, and the third covering portion 33 is a housing portion S in which the battery cell 23 is housed.

The

first end portions

32a and 33a in the longitudinal direction of the second covering portion 32 and the third covering portion 33 are connected to the second covering portion 32 and the third covering portion 33, respectively. A rectangular flat plate-like projecting portion 35 extending in the longitudinal direction of the covering portion 33 is provided. In addition, square

columnar leg portions

36 and 36 are provided at

second end portions

32 c and 33 c in the longitudinal direction of the second covering portion 32 and the third covering portion 33, respectively.

As shown in FIG. 1, the pair of

brackets

25, 25 are provided at both ends of the battery cells 23 arranged in parallel in one direction D. The bracket 25 has a clamping part 25a, a fixing part 25b, and an insertion hole 25c formed in the fixing part 25b. The battery module 21 is fixed to the housing 11 by fixing the fixing portion 25 b of the bracket 25 to the side wall 13. Specifically, the bracket 25 is fixed to the housing 11 by a bolt (not shown) inserted through the insertion hole 25 c being screwed into the side wall 13.

As shown in FIG. 2, the elastic member 47 is disposed at one end of the array 28. The array body 28 and the elastic member 47 are restrained in a state where they are pressed in the array direction (one direction D) of the battery cells 23 by bolts B and nuts N described in detail later. The elastic member 47 is made of an elastic material such as urethane rubber. The elastic member 47 absorbs the expansion of the battery cell 23 within a certain range.

As shown in FIG. 2, the bolt B and the nut N connect the pair of

brackets

25, 25 to each other. Bolts B are inserted through the pair of

brackets

25, 25. The bolt B is inserted from one bracket 25 toward the other bracket 25 and is screwed into the nut N at a position where the other bracket 25 is inserted. The pair of

brackets

25, 25 are in contact with a plurality of battery cells 23 arranged in one direction D and a main surface 24 c (see FIG. 3) that is a surface intersecting with one direction D (arrangement direction) of the battery cells 23. The arrangement body 28 and the elastic member 47 including the plurality of heat transfer plates 41 arranged so as to be restrained in a state of being pressed in one direction D.

As shown in FIGS. 3, 4, 5 </ b> A and 5 </ b> B, the heat transfer plate 41 is disposed in contact with the main surface 24 c of the battery cell 23 accommodated in the battery holder 22. It is a plate-shaped member. The heat transfer plate 41 is formed, for example, by bending a metal plate made of aluminum, and is perpendicular to a rectangular flat plate-like first main body portion 42 and one end portion 43 b in the longitudinal direction of the first main body portion 42 ( And a rectangular flat plate-like second main body portion 43 bent at 90 degrees. The first main body portion 42 is provided in the accommodating portion S in a state adjacent to the battery cell 23 in the thickness direction of the battery cell 23. The second main body portion 43 is opposed to one surface of the second covering portion 32 (the surface on the opposite side of the accommodating portion S in the thickness direction surface of the second covering portion 32).

The second main body 43 is bent 90 degrees from the first main body 42. In other words, the first main body portion 42 and the second main body portion 43 intersect at 90 degrees. The second main body 43 is bent from the first main body 42 in the direction in which the elastic member 47 is disposed. As shown in FIG. 4, the battery module 21 is adjacent to the other end portion 43 a of the second main body portion 43 opposite to the one end portion 43 b and the direction in which the second main body portion 43 is bent from the first main body portion 42. And a heat transfer plate 41 arranged in a distance G. The distance G in this embodiment is a distance (predetermined distance) according to the amount of movement of the heat transfer plate 41 that moves in one direction D due to the expansion of the battery cell 23, and the heat transfer plate that moves due to the expansion of the battery cell 23. It is longer than the maximum movement amount of 41. As shown in FIG. 5B, the length L2 of the second main body 43 in one direction D is 1 to 10 times the thickness L1 of the first main body 42 in one direction D (usually 5 times). ).

Specifically, as shown in FIG. 4, the battery cell 23A, the battery cell 23B, the battery cell 23, the battery cell 23D, the battery cell 23E, the battery cell 23F, and the battery cell 23G are arranged in this order from one end side of the array 28. Is arranged in. The other end portion 43a of the second body portion 43 of the heat transfer plate 41G that contacts the main surface 24c of the battery cell 23G, and the heat transfer disposed adjacent to the first body portion 42 in the direction in which the second body portion 43 is bent. The heat plate 41F is separated by a distance G. Similarly, the distance between the other end 43a of the second main body 43 of the heat transfer plate 41F that contacts the main surface 24c of the battery cell 23F and the heat transfer plate 41E, the heat transfer plate that contacts the main surface 24c of the battery cell 23E. The other end 43a and the heat transfer plate in the second main body 43 of the heat transfer plate 41D contacting the main surface 24c of the battery cell 23D, the separation distance between the other end 43a and the heat transfer plate 41D in the second main body 43 of 41E. The distance between 41C, the distance between the other end 43a and the heat transfer plate 41B of the second body 43 of the heat transfer plate 41C that contacts the main surface 24c of the battery cell 23C, and the main surface 24c of the battery cell 23B. The separation distance between the other end 43a of the second main body 43 of the heat transfer plate 41B and the heat transfer plate 41A is the distance G.

As shown in FIG. 5B, a curved portion 44 is formed on the first body portion 42 side of the second body portion 43. For example, when the thickness of the heat transfer plate 41 is 3 mm, the curved portion 44 can have a curved radius of the outer portion 44a of 6 mm and a curved radius of the inner portion 44b of 3 mm. A part of the curved portion 44 is in contact with a heat conducting member 51 described later. The radius of the curve in the curve portion 44 is preferably as small as possible.

The battery module 21 having the above-described configuration is attached to the side wall 13 of the housing 11 to form a battery pack 10 as shown in FIG. As shown in FIGS. 6 and 7, when the battery module 21 is attached to the side wall 13 of the housing 11, it is attached by a pair of

brackets

25, 25. Further, a TIM (Thermal Interface Material) as the heat conducting member 51 is disposed between the array 28 and the side wall 13. That is, the 2nd main-body part 43 of the heat-transfer plate 41 is contacting the side wall 13 of the housing | casing 11 via TIM.

The heat conducting member 51 is a member made of a sheet-like material having adhesiveness on both sides. The heat conducting member 51 has insulating properties. As the heat conductive member having such an insulating property, a heat conductive sheet not including a metal filler can be used. In addition, the heat conductive member 51 includes a silicone heat conductive sheet and an acrylic heat conductive sheet. When a silicone-based heat conductive sheet is used, the range of operating temperature can be widened because of excellent cold resistance and heat resistance. In addition, a silicone-based heat conductive sheet that does not use a metal filler is suitable for an insulating material because the change in electrical characteristics due to temperature and frequency is small. On the other hand, since the acryl-based sheet does not generate siloxane gas, the contact failure of the mechanical contact and the abrasion do not occur in the sealed space. Acrylic sheets are generally less expensive than silicone.

Next, the function and effect of the battery module 21 of the above embodiment will be described. In the battery module 21 of the above embodiment, as shown in FIG. 4, the other end portion 43 a of the second main body portion 43 and the second main body portion 43 are disposed adjacent to each other in a direction in which the second main body portion 43 is bent. The heat transfer plate 41 is separated. For example, as shown in FIG. 8A, in the direction in which the second main body 43 is bent from the other end 43a of the second main body 43 of the heat transfer plate 41G and the first main body 42 of the heat transfer plate 41G. The heat transfer plates 41F arranged adjacent to each other are separated from each other. Moreover, the heat transfer plate 41E arrange | positioned adjacent to the other end part 43a in the 2nd main-body part 43 of the heat-transfer plate 41F, and the direction in which the 2nd main-body part 43 bends from the 1st main-body part 42 of the heat-transfer plate 41F. Are separated from each other.

Furthermore, the separation distance is a distance G corresponding to the amount of movement in one direction of the heat transfer plate due to the expansion of the battery cells. The adjustment of the distance to be separated means that the one heat transfer plate 41 and the heat transfer plate 41 when the one heat transfer plate 41 (for example, the heat transfer plate 41G) is moved by the expansion of the battery cell 23. Adjusting the length of the overlapping portion in one direction D with the heat conducting member 51 deformed by pressing of another heat transfer plate 41 (for example, heat transfer plate 41F) adjacent to one direction (movement direction) D Means. Since the overlapping portion can be a portion where one heat transfer plate does not come into contact with the heat conducting member, in the battery module 21 having the heat transfer plate 41 in which the overlapping amount (that is, the distance G) is appropriately adjusted, the heat dissipation efficiency. Can be suppressed.

8B, in the battery module 21 of the above embodiment, the distance G is longer than the maximum movement amount M of the heat transfer plate 41 due to the expansion of the battery cells 23. According to the battery module 21 having this configuration, the expansion of the battery cell 23 causes the heat transfer plate 41 to move from the position shown in FIG. 8A to the position shown in FIG. 8B. Even if it exists, the other end part 43a of the 2nd main-body part 43 does not move to the position H1, H2 in which the heat-transfer plate 41 arrange | positioned adjacent to the moving direction was arrange | positioned.

Specifically, even when the heat transfer plate 41G moves due to the expansion of the battery cell 23, the position H1 of the heat conducting member 51 deformed by pressing of the heat transfer plate 41F arranged adjacent to the moving direction. Never move up to. That is, the state where the second main body 43 of the heat transfer plate 41G and the heat conducting member 51 are in contact with each other is maintained. Similarly, even when the heat transfer plate 41F moves due to the expansion of the battery cell 23, the heat transfer member 51 is deformed by the pressing of the heat transfer plate 41E arranged adjacent to the moving direction to the position H2 of the heat transfer member 51. Never move. Therefore, a part of the second main body 43 does not come into contact with the heat conducting member 51. As a result, it is possible to further suppress a decrease in heat dissipation efficiency.

The battery module 21 of the above embodiment further includes an elastic member 47 disposed at one end of the array 28, and the pair of

brackets

25 and 25 connect the array 28 and the elastic member 47 in one direction D. It restrains in the state pressurized. In the battery module 21 having this configuration, the expansion of the battery cell 23 can be absorbed within a certain range.

Although one embodiment has been described above, one aspect of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.

In the above embodiment, the heat transfer plate 41 having the rectangular flat plate-like second main body portion 43 bent at a right angle (90 degrees) from the one end portion 43b of the first main body portion 42 has been described as an example. One aspect of the present invention is not limited to this, and the heat transfer plate 41 may have, for example, a second main body portion 43 that bends at 60 to 90 degrees. The bending angle can be selected in accordance with a multiple of the length L2 of the second main body portion. In addition, the battery module 21 includes a heat transfer plate 41 having a rectangular flat plate-like second body portion 43 bent at a right angle (90 degrees) from one end portion 43 b of the first body portion 42, and one end portion of the first body portion 42. A heat transfer plate having a rectangular flat plate-like second main body portion 43 bent from 60 degrees to less than 90 degrees from 43 b may be mixed.

In the said embodiment or modification, the heat transfer plate 41 which has the 2nd main-body part 43 of the rectangular flat plate bent at right angles (90 degree | times) from the one end part 43b of the 1st main-body part 42 is mentioned as an example, and is demonstrated. However, it is good also as a heat-transfer plate of the shape which is not bent from the one end part 43b of the 1st main-body part 42. FIG. In other words, it is good also as a heat-transfer plate which does not have the 2nd main-body part 43. FIG. Further, the battery module 21 includes the different heat transfer plates described in the above embodiment or modification (the rectangular plate-like second main body portion 43 bent at a right angle (90 degrees) from the one end portion 43b of the first main body portion 42). The heat transfer plate 41 having the second main body 43, the heat transfer plate having the second main body 43, and the second main body 43 having a rectangular flat plate shape bent from the one end 43b of the first main body 42 to 60 degrees or more and less than 90 degrees. A structure in which a heat plate or the like is arbitrarily combined may be employed.

In the embodiment or the modification, as shown in FIG. 4, in all the heat transfer plates 41, the length L2 of the second main body portion 43 is all the same (in other words, the distance G is all the same). Although described above, one aspect of the present invention is not limited to this. For example, the length L2 of the second main body portion 43 in the one direction D may be a battery module configured to increase gradually or stepwise as the distance from the elastic member 47 in the one direction D increases. In other words, the battery module may be configured such that the distance G decreases gradually or stepwise as the distance from the elastic member 47 increases in one direction D.

In the battery module according to this modification, even when the heat transfer plate 41 moves due to the expansion of the battery cells 23, the heat conductive member deformed by the pressure of the heat transfer plate 41 arranged adjacent to the moving direction. The possibility of moving to the position 51 can be reduced. As a result, it is possible to further suppress a decrease in heat dissipation efficiency.

In the said embodiment or modification, although the 2nd main-body part 43 in the heat-transfer plate 41 gave and demonstrated the example bent in the direction in which the elastic member 47 was arrange | positioned from the 1st main-body part 42, all the heat transfer was demonstrated. A part or all of the second main body 43 in the plate 41 may be bent from the first main body 42 to the opposite side to the direction in which the elastic member 47 is arranged.

In the embodiment or the modification, the battery module 21 according to the embodiment smoothly connects the first body portion 42 and the second body portion 43 between the first body portion 42 and the second body portion 43. Although the example provided with the heat-transfer plate 41 by which the curved part 44 to arrange | position is given and demonstrated, the 1st main-body part 42 and the 2nd main-body part 43 are provided with the heat-transfer plate 41 in which the curved part 44 does not exist. It may be. In addition, the second main body 43 is not flat as in the above-described embodiment or modification, and is formed, for example, in a shape that bends upward (in a direction away from the heat conducting member 51) or has a thin tip. Or you may. Thereby, the catching to the heat conductive member 51 of the heat-transfer plate 41 can be reduced, and damage to the heat conductive member 51 can be reduced.

In the above-described embodiment or modification, the example in which the array body 28 is restrained in a state of being pressed in one direction D by the pair of

brackets

25 and 25 has been described, but a pair that does not have a function of attaching to the housing 11. The end plate may be constrained in a state where the array body 28 is pressurized in one direction D.

In the above embodiment or modification, the elastic member 47 has been described with an example in which only one elastic member 47 is disposed at one end of the array 28 as shown in FIG. 9A. One aspect is not limited to this. For example, the elastic member 47 may be disposed at both ends of the array 28, or may be disposed between the battery cells 23. Moreover, the elastic member 47 may be arrange | positioned among all or one part battery cells 23, as FIG.9 (B) shows.

In the above-described embodiment or modification, the elastic member 47 formed of an elastic material such as urethane rubber has been described as an example. However, one aspect of the present invention is not limited thereto, for example, a spring or the like. The elastic member may be used.

In the said embodiment or modification, although the battery module 21 in which the battery cell 23 of the state hold | maintained at the battery holder 22 was arranged in parallel was mentioned as an example, it was not hold | maintained at the battery holder 22, but only the battery cell 23 was demonstrated. You may use the battery module 21 which consists of.

In the above-described embodiment or modification, the side wall 13 of the casing 11 in the battery pack 10 is described as an example of the member to be fixed, but a counterweight mounted on an industrial vehicle may be used.

Various embodiments and modifications described above may be combined in various ways without departing from the spirit of one aspect of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Battery pack, 11 ... Housing | casing, 13 ... Side wall, 21 ... Battery module, 22 ... Battery holder, 23 (23A-23G) ... Battery cell, 24c ... Main surface, 25 ... Bracket (restraint part), 28 ... Arrangement Body 41 (41A to 41G) ... heat transfer plate 42 ... first body part 43 ... second body part 43a ... other end part 43b ... one end part 47 ... elastic member 51 ... heat conducting member B ... bolts (restraints), N ... nuts (restraints), D ... unidirectional.

Claims

A battery module attached to the housing via a heat conducting member,
A plurality of battery cells arranged in one direction, and a plurality of heat transfer plates arranged in contact with a main surface that is a surface intersecting the one direction of the battery cells and arranged in the one direction. An array having
A restraining portion for restraining the arrayed body in a state of being pressed in the one direction,
The heat transfer plate is
A first main body that contacts the main surface;
A second body part that is bent in a direction intersecting the main surface from one end part of the first body part and is in contact with the heat conducting member;
The other end portion of the second main body portion opposite to the one end portion, and the heat transfer plate disposed adjacent to the first main body portion in a direction in which the second main body portion bends, Are located at a distance,
The said predetermined distance is a battery module which is a distance according to the moving amount | distance in the said one direction of the said heat-transfer plate by expansion | swelling of the said battery cell.
2. The battery module according to claim 1, wherein a length of the second main body portion in the one direction is 1 to 10 times a thickness of the first main body portion in the one direction.
The battery module according to claim 1 or 2, wherein the predetermined distance is longer than a maximum movement amount of the heat transfer plate due to expansion of the battery cell.
An elastic member disposed at one end of the array;
The battery module according to any one of claims 1 to 3, wherein the restraining portion restrains the array body and the elastic member in a state where the array member and the elastic member are pressed in the one direction.
5. The battery module according to claim 4, wherein a length of the second main body portion in the one direction is longer as a heat transfer plate is in contact with the battery cell arranged at a position far from the elastic member in the one direction.