WO2015170581A1

WO2015170581A1 - Battery module

Info

Publication number: WO2015170581A1
Application number: PCT/JP2015/062078
Authority: WO
Inventors: 和樹前田; 加藤　崇行; 浩生植田; 直人守作
Original assignee: 株式会社豊田自動織機
Priority date: 2014-05-07
Filing date: 2015-04-21
Publication date: 2015-11-12

Abstract

The battery module comprises a plurality of battery cells, first and second end plates, an intermediary plate, an elastic member, and a support member. The battery cells are arranged into one row. The first and second end plates sandwich the plurality of battery cells from the two sides in the arrangement direction thereof. The intermediary plate is disposed between the first end plate and the battery cell that is adjacent to said first end plate and is constituted so as to move in the arrangement direction along with the swelling of the plurality of battery cells. The elastic member is provided between the intermediary plate and the first end plate, and constituted in such a way as to deform elastically when pressed due to the movement of the intermediary plate accompanying the swelling of the battery cells. The support member is retained by the first end plate and supports the intermediary plate from a direction orthogonal to the arrangement direction.

Description

Battery module

The present invention relates to a battery module having a plurality of battery cells.

A battery module in which a plurality of battery cells are connected to form a module is described in Patent Document 1, for example. In Patent Document 1, a plurality of battery cells are arranged in a line to constitute a battery module.

JP 2010-211962 A

When vibration or impact is applied to the battery module, some battery cells may be displaced, and the battery module may be deformed due to such displacement. If the battery module is deformed, the connection between the battery cells cannot be maintained, or the members constituting the battery module may be damaged. Therefore, it is desired to suppress the deformation of the battery module.

An object of the present invention is to provide a battery module capable of suppressing deformation.

A battery module that solves the above problems includes a plurality of battery cells arranged in a row, a first end plate and a second end plate that sandwich the plurality of battery cells from both sides in the arrangement direction, and the first end plate. And an intermediate plate provided between the battery cells adjacent to the first end plate and configured to move in the arrangement direction with expansion of the plurality of battery cells, the intermediate plate, and the first An elastic member provided between the end plate and configured to be elastically deformed by being pressed by the movement of the intermediate plate accompanying expansion of the battery cell, and held by the first end plate, And a support member that supports from a direction orthogonal to the arrangement direction.

The perspective view which shows the battery module of one Embodiment. Sectional drawing of the battery module of FIG. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2. The perspective view which shows the battery cell of FIG. 2, a battery holder, a heat-transfer plate, and an intermediate | middle plate. FIG. 5A is a front view showing the first end plate of FIG. 2, and FIG. 5B is a sectional view taken along line 5b-5b of FIG. The front view which shows the 2nd end plate of FIG. The disassembled perspective view which shows the assembly | attachment aspect of the member which comprises the battery module of FIG. The perspective view which shows the 1st cover member of FIG. The perspective view which shows the 2nd cover member of FIG.

Hereinafter, an embodiment of the battery module 10 will be described.
As shown in FIGS. 1 and 2, the battery module 10 includes a plurality of battery cells 11 arranged in a row and a plurality of heat transfer plates 41. The battery cells 11 and the heat transfer plates 41 are alternately arranged. Each of the plurality of battery holders 20 holds one battery cell 11 and one heat transfer plate 41. The battery cell 11 and the heat transfer plate 41 are sandwiched between a first end plate 61 and a second end plate 62 provided on both sides of the battery cell 11 in the arrangement direction. Hereinafter, one of the battery cells 11 at both ends in the arrangement direction is a first battery cell 11a, and the other is a second battery cell 11b. The first battery cell 11 a is adjacent to the first end plate 61, and the second battery cell 11 b is adjacent to the second end plate 62.

As shown in FIGS. 2 and 3, a flat intermediate plate 51 is provided between the first end plate 61 and the first battery cell 11a. A flat elastic member 31 is provided between the intermediate plate 51 and the first end plate 61. The elastic member 31 is made of an elastically deformable material such as rubber or a resin sponge.

No elastic member is provided between the second end plate 62 and the second battery cell 11b. That is, the first and

second end plates

61 and 62 can connect the plurality of battery cells 11 from both sides in the arrangement direction of the battery cells 11 without interposing an elastic member between the second end plate 62 and the second battery cell 11b. It is pinched. The battery holder 20 and the intermediate plate 51 are made of resin, and the

end plates

61 and 62 are made of metal.

As shown in FIG. 4, the battery holder 20 has a first covering wall 21 having a rectangular flat plate shape. A rectangular flat plate-like second covering wall 22 and a third covering wall 23 are respectively provided at both ends in the longitudinal direction of the first covering wall 21. The second and third covering

walls

22 and 23 extend in the thickness direction of the first covering wall 21, in other words, in the direction orthogonal to the first covering wall 21. A region surrounded by the first covering wall 21, the second covering wall 22, and the third covering wall 23 is a housing portion S in which the battery cell 11 is housed.

The second covering wall 22 has a first end 22a in the longitudinal direction and a second end 22c in the longitudinal direction opposite to the first end 22a. The third covering wall 23 has a longitudinal first end 23a and a longitudinal second end 23c opposite to the first end 23a. The first covering wall 21 is connected to the

second ends

22 c and 23 c in the longitudinal direction of the second and third covering

walls

22 and 23. The rectangular flat plate-like fourth covering wall 24 is connected to the first

longitudinal ends

22 a and 23 a of the second and third covering

walls

22 and 23. The fourth covering wall 24 extends between the

first ends

22 b and 23 b in the short direction of the covering

walls

22 and 23. The thickness direction of the fourth covering wall 24 coincides with the short direction of the

covering walls

22 and 23. The second covering wall 22 and the third covering wall 23 face each other in the longitudinal direction of the fourth covering wall 24. The direction perpendicular to both the thickness direction and the longitudinal direction of the fourth covering wall 24 is the short direction of the fourth covering wall 24.

In the vicinity of both ends in the longitudinal direction of the fourth covering wall 24, terminal accommodating portions 25 that are U-shaped and open in the thickness direction of the fourth covering wall 24 are provided. The terminal accommodating portion 25 is continuous with the second covering wall 22 and the third covering wall 23, respectively.

The fourth covering wall 24 is provided with two square columnar column portions 26, and each column portion 26 is adjacent to the corresponding terminal accommodating portion 25. Each column portion 26 has an axis extending in the short direction of the

covering walls

22 and 23. Each column part 26 has an insertion hole 26 a, and each insertion hole 26 a extends in the axial direction of the column part 26 so as to penetrate the corresponding column part 26.

A rectangular flat plate-like projecting wall 27 extends from the first

longitudinal ends

22a, 23a of the second covering wall 22 and the third covering wall 23 in the longitudinal direction of the

corresponding covering walls

22, 23, and is opposed to each other. Each protruding wall 27 is formed integrally with the

corresponding covering wall

22, 23. Square columnar leg portions 28 are provided on the

second end portions

22c and 23c in the longitudinal direction of the second covering wall 22 and the third covering wall 23, respectively. Each leg portion 28 has an axis extending in the short direction of the

covering walls

22 and 23. Each leg portion 28 has an insertion hole 28 a, and each insertion hole 28 a extends in the axial direction of the leg portion 28 so as to penetrate the corresponding leg portion 28.

The battery cell 11 includes a case 12 and an electrode assembly 13 housed in the case 12 and having a positive electrode and a negative electrode. The case 12 includes a square cylindrical case main body 14 having a bottom and an opening, and a lid member 15 that closes the opening. The lid member 15 is provided with two terminals 16, that is, a positive terminal and a negative terminal. A connection member for connecting the battery cells 11 to each other is connected to each terminal 16.

The heat transfer plate 41 is formed by bending a metal plate material into an L shape. The heat transfer plate 41 includes a rectangular flat plate-like main body 42 and a bent portion 43 extending from one end in the longitudinal direction of the main body 42 in the thickness direction of the main body 42.

The intermediate plate 51 has a rectangular flat base 52. The base 52 includes a plurality of

protrusions

53 and 54 that extend in opposite directions from both short-side ends of the base 52. More specifically, two first protrusions 53 are provided at one end of the both ends in the short direction of the base 52, and two second protrusions 54 are provided at the other end. .

The first protrusions 53 are provided in the longitudinal direction of the base 52 at a position near the center in the longitudinal direction of the base 52 and spaced from each other. Each first protrusion 53 has an intermediate bolt hole 55 and a through hole 56 that penetrate the first protrusion 53 in the thickness direction. The interval between the intermediate bolt holes 55 is the same as the interval between the insertion holes 26 a of the column part 26 of the battery holder 20.

The second protrusions 54 are provided near both ends of the base 52 in the longitudinal direction. Each second protrusion 54 has an intermediate bolt hole 57. The interval between the intermediate bolt holes 57 is the same as the interval between the insertion holes 28 a of the leg portions 28 of the battery holder 20.

As shown in FIGS. 5A and 5B, the first end plate 61 has a plate base 63 having a rectangular flat plate shape. The plate base 63 has two first plate protrusions 64 and two second plate protrusions 65 extending in opposite directions from both ends in the short direction of the plate base 63.

Each first plate protrusion 64 has a first bolt hole 66 that penetrates the first plate protrusion 64 in the thickness direction. The distance between the first bolt holes 66, that is, the distance between the centers of the first bolt holes 66 is the same as the distance between the insertion holes 26 a of the column part 26 of the battery holder 20. Each second plate protrusion 65 has a first bolt hole 67 that penetrates the second plate protrusion 65 in the thickness direction. The distance between the first bolt holes 67, that is, the distance between the centers of the first bolt holes 67 is the same as the distance between the insertion holes 28 a of the leg portions 28 of the battery holder 20. The diameter of the first bolt hole 66 is the same as the diameter of the first bolt hole 67.

In the plate base 63, two screw holes 68 are provided around each of the two

plate protrusions

64 and 65 around the two

plate protrusions

64 and 65. Each screw hole 68 has a female screw on its inner peripheral surface.

Four positioning plates 70 are fixed to the first end plate 61. The positioning plates 70 are provided at four locations, that is, locations corresponding to the total four

plate protrusions

64 and 65, respectively. Each positioning plate 70 has a small hole 71 that penetrates the positioning plate 70 in the thickness direction and aligns with the first bolt holes 66 and 67 of the

corresponding plate protrusions

64 and 65. The diameter of the small hole 71 is smaller than the diameter of the first bolt holes 66 and 67. Each positioning plate 70 has two fixing holes 72 that penetrate the positioning plate 70 in the thickness direction and align with the two screw holes 68 of the first end plate 61. The diameter of the fixing hole 72 is larger than the diameter of the screw hole 68.

As shown in FIG. 6, the second end plate 62 has a plate base 73, two first plate protrusions 74 and two second plate protrusions 75 extending from the plate base 73. The shape of the plate base 73 is the same as the shape of the plate base 63 of the first end plate 61. The shapes of the first and

second plate protrusions

74 and 75 are the same as the shapes of the first and

second plate protrusions

64 and 65 of the first end plate 61. That is, the outer shape of the second end plate 62 is the same as the outer shape of the first end plate 61. Each first plate protrusion 74 has a second bolt hole 76 that penetrates the first plate protrusion 74 in its thickness direction. The distance between the second bolt holes 76, that is, the distance between the centers of the second bolt holes 76 is the same as the distance between the insertion holes 26 a of the column part 26 of the battery holder 20. Each first plate protrusion 74 has a through-hole 77 that passes through the first plate protrusion 74 in the thickness direction.

Each second plate protrusion 75 has a second bolt hole 78 that penetrates the second plate protrusion 75 in the thickness direction. The distance between the second bolt holes 78, that is, the distance between the centers of the second bolt holes 78 is the same as the distance between the insertion holes 28 a of the legs 28 of the battery holder 20. The diameter of the second bolt hole 76 is the same as the diameter of the second bolt hole 78. The diameters of the second bolt holes 76 and 78 of the second end plate 62 are smaller than the diameters of the first bolt holes 66 and 67 of the first end plate 61.

As shown in FIGS. 2 and 3, the plurality of battery cells 11, the plurality of heat transfer plates 41, the plurality of battery holders 20, the intermediate plate 51, and the elastic member 31 include a first end plate 61 and a second end plate 62. It is pinched by. Since the thickness direction of the elastic member 31, the thickness direction of the intermediate plate 51, and the thickness direction of the

end plates

61 and 62 are the same as the arrangement direction of the battery cells 11, these thickness directions are hereinafter simply referred to as “thickness direction”. That's it. The battery cells 11 adjacent to each other in the arrangement direction of the battery cells 11 and the main body 42 of the heat transfer plate 41 are bonded to each other by an adhesive sheet 32 having adhesive force. Thereby, the adjacent battery cell 11 is adhere | attached with the heat-transfer plate 41 so that the heat-transfer plate 41 may be pinched | interposed. Similarly, the first battery cell 11 a and the intermediate plate 51 are bonded by an adhesive sheet 32, and the second battery cell 11 b and the second end plate 62 are bonded by an adhesive sheet 32. Further, the intermediate plate 51 and the elastic member 31 are bonded by an adhesive sheet 32. The bent portion 43 of each heat transfer plate 41 covers the second covering wall 22 of the corresponding battery holder 20. Each bent portion 43 is in close contact with a housing or the like via a heat conductive member (not shown).

As shown in FIG. 7, each positioning plate 70 is fixed to the plate base 63 of the first end plate 61 by two screws S1. Screws S <b> 1 are inserted into the two fixing holes 72 of each positioning plate 70, and these screws S <b> 1 are screwed into the screw holes 68 of the first end plate 61. Thereby, the positioning plate 70 is provided so that the small hole 71 of each positioning plate 70 and the corresponding first bolt holes 66 and 67 of the first end plate 61 are aligned.

The small holes 71 of the four positioning plates 70, the four first bolt holes 66, 67 of the first end plate 61, the four intermediate bolt holes 55, 57 of the intermediate plate 51, and the four

insertion holes

26a, 28a of the battery holder 20. The four bolts 80 are inserted through the four second bolt holes 76 and 78 of the second end plate 62 in the arrangement direction of the battery cells 11, respectively. Each bolt 80 is screwed with a nut 85. A load (restraint load) acts on the first end plate 61 and the second end plate 62 in a direction approaching each other, whereby the

end plates

61 and 62 restrain the battery cell 11. The intermediate bolt holes 55 and 57 of the intermediate plate 51, the first bolt holes 66 and 67 of the first end plate 61, and the second bolt holes 76 and 78 of the second end plate 62 function as bolt holes.

The bolt 80 is inserted into the intermediate bolt holes 55 and 57 of the intermediate plate 51 and the first bolt holes 66 and 67 of the first end plate 61, so that the intermediate plate 51 is orthogonal to the arrangement direction of the battery cells 11 by the bolts 80. It is supported from the direction to do. That is, the movement of the intermediate plate 51 in the direction orthogonal to the arrangement direction of the battery cells 11 with the elastic deformation of the elastic member 31 is restricted by the bolt 80 held by the first end plate 61.

Each bolt 80 has a head part 81 and a shaft part 82. The shaft portion 82 includes a cylindrical portion 83 that extends in the axial direction from the head portion 81 and a screw portion 84 that extends in the axial direction from the tip of the cylindrical portion 83. The diameter of the screw portion 84 is smaller than the diameter of the cylindrical portion 83. The diameter of the threaded portion 84 is the diameter of the top of the thread. That is, the bolt 80 of the present embodiment is a stepped bolt having a step at the boundary between the cylindrical portion 83 and the screw portion 84. The diameter of the cylindrical portion 83 is smaller than the diameter of the small hole 71 of the positioning plate 70 and larger than the second bolt holes 76 and 78 of the second end plate 62. Since the diameter of the small hole 71 is smaller than the first bolt holes 66 and 67 of the first end plate 61, the diameter of the cylindrical portion 83 is smaller than the first bolt holes 66 and 67 of the first end plate 61. The diameter of the screw portion 84 is smaller than the second bolt holes 76 and 78 of the second end plate 62.

The bolts 80 are inserted from the first bolt holes 66 and 67 of the first end plate 61 toward the second bolt holes 76 and 78 of the second end plate 62 through the small holes 71 of the positioning plate 70. . A nut 85 is screwed onto the tip of each bolt 80 that extends outward beyond the second end plate 62.

The cylindrical portion 83 of each bolt 80 extends from the first end plate 61 to a position beyond the intermediate plate 51. Since the diameter of the first bolt holes 66 and 67 of the first end plate 61 is larger than the diameter of the small hole 71, the outer peripheral surface of each cylindrical portion 83 is in contact with the inner peripheral surface of the corresponding small hole 71, It does not contact the inner peripheral surface of the corresponding

first bolt hole

66, 67. Therefore, the first end plate 61 holds the bolt 80 via the positioning plate 70 fixed to the first end plate 61.

As shown in FIGS. 1 and 2, the battery module 10 has a cover 90. The cover 90 faces the surface of the battery cell 11 on which the terminal 16 is provided, in other words, the cover member 15, and is disposed between the two protruding walls 27 of each battery holder 20. The cover 90 includes a first cover member 91 and a second cover member 92. The first cover member 91 and the second cover member 92 are arranged in the arrangement direction of the battery cells 11.

As shown in FIG. 8, the first cover member 91 has a rectangular flat plate-like main body 93. The main body 93 includes side wall portions (standing wall portions) 94 extending from both longitudinal ends of the main body 93 in the thickness direction of the main body 93. The main body 93 has a through hole 95 that penetrates the main body 93 in the thickness direction. The through hole 95 is provided near one corner of the four corners of the main body 93.

The main body 93 includes two square columnar fixing portions 96 on the surface opposite to the surface on which the side wall portion 94 is provided (the surface facing the lid member 15). The fixing portions 96 are both provided at one of the end portions of the main body 93 in the short direction. The fixing portions 96 are provided at intervals in the longitudinal direction of the main body 93. A nut 97 is embedded in each fixing portion 96 by insert molding or the like. The interval between the nuts 97 embedded in the fixing portion 96, that is, the distance between the centers of the nuts 97 is the same as the interval between the through holes 56 of the intermediate plate 51.

In the first cover member 91, a fixing plate 98 is provided on the surface of the main body 93 in the thickness direction where the side wall portion 94 is provided (the surface opposite to the surface on which the fixing portion 96 is provided). Yes. The fixing plate 98 is provided in the vicinity of the through hole 95. A nut 99 is embedded in the fixed plate 98 by insert molding or the like.

As shown in FIG. 9, the second cover member 92 has the same configuration as the first cover member 91 except that the fixing plate 98 is not provided. Are given the same reference numerals and their description is omitted.

As shown in FIG. 1, the first cover member 91 and the second cover member 92 are arranged so that the corners of the main body 93 adjacent to the through hole 95 are located diagonally. In the arrangement direction of the battery cells 11, the first cover member 91 is located closer to the first end plate 61, and the second cover member 92 is located closer to the second end plate 62. The side wall portion 94 of the first cover member 91 and the side wall portion 94 of the second cover member 92 are provided along the protruding wall 27 of the battery holder 20, respectively. The first cover member 91 and the second cover member 92 are not fixed to each other and can be separated from each other.

As shown in FIG. 7, both fixing portions 96 of the first cover member 91 are positioned between the two column portions 26 of each battery holder 20. The intermediate plate 51 is fixed to the first cover member 91 by screwing the screws S <b> 2 inserted through the through holes 56 of the intermediate plate 51 into the nuts 99 embedded in the fixing portion 96. Although not shown, the screws inserted into the through holes 77 of the second end plate 62 are screwed into the nuts 97 embedded in the fixing portions 96 of the second cover member 92, so that the first The two end plates 62 are fixed to the second cover member 92.

As shown in FIG. 1, the first cover member 91 is equipped with a monitoring ECU 101 that monitors the battery module 10 and shuts off the discharge when an abnormality occurs in the battery module 10 (or the battery cell 11). Is placed. A columnar bus bar 102 is inserted into the through hole 95 of the first cover member 91. The bus bar 102 is bent in an L shape. The bus bar 102 is connected to the terminal 16 of the first battery cell 11 a and is inserted through the through hole 95 of the first cover member 91 and protrudes above the cover member 91. The screw S3 penetrating the bus bar 102 is screwed into a nut 99 embedded in the fixing plate 98, whereby the bus bar 102 is fixed to the first cover member 91.

On the second cover member 92, an electronic component 103 such as a current sensor or FET (electrolytic effect transistor) is placed.
Next, the operation of the battery module 10 of the present embodiment will be described.

Each battery cell 11 is formed with a film on the surface of the electrode with use. Each battery cell 11 expand | swells because a film becomes thick. The elastic member 31 provided between the second end plate 62 and the second battery cell 11b elastically deforms and contracts when the battery cell 11 expands. As a result, the load applied to the

end plates

61 and 62 as the battery cell 11 expands is absorbed. Specifically, when the battery cells 11 expand, the adjacent battery cells 11 are pressed against each other. The intermediate plate 51 is pressed toward the elastic member 31 by the expansion of the adjacent battery cells 11 and moves toward the elastic member 31. The elastic member 31 is elastically deformed by being pressed by the moving intermediate plate 51.

The elastic member 31 is restricted from moving in the thickness direction by the

end plates

61 and 62 being constrained by the bolts 80 and nuts 85, and is elastically deformed in the thickness direction due to factors other than the expansion of the battery cell 11. Is suppressed. On the other hand, the elastic member 31 is not restricted from moving in the direction orthogonal to the thickness direction, and the elastic member 31 may be elastically deformed in the direction orthogonal to the thickness direction when vibration or impact is applied. . If the elastic member 31 is in direct contact with the battery cell 11, the battery cell 11 may move following the elastic deformation of the elastic member 31 and the battery module 10 may be deformed. When the battery cells 11 are respectively held in the battery holder 20 as in the present embodiment, a load is applied to the battery holder 20 by the movement of the battery cells 11, and the column part 26 and the legs through which the bolts 80 are inserted. The load is concentrated on the portion 28. And there exists a possibility that the pillar part 26 and the leg part 28 may deform | transform. If the battery module 10 is deformed, the connection state between the battery cells 11 may not be maintained, or members constituting the battery module 10 may be damaged. Further, when the battery cell 11 is dissipated by bringing the bent portion 43 into close contact with the housing or the like, if the bent portion 43 is separated from the housing or the like due to a load, the heat dissipation of the battery cell 11 is reduced.

When the intermediate plate 51 is provided between the elastic member 31 and the first battery cell 11a, when the elastic member 31 is elastically deformed in a direction orthogonal to the thickness direction, the intermediate plate 51 is moved in a direction orthogonal to the thickness direction. The moving force of acts. In the present embodiment, since the bolts 80 are inserted into the intermediate bolt holes 55 and 57 of the intermediate plate 51, the bolts 80 corresponding to the peripheral edges of the intermediate bolt holes 55 and 57 abut, and the bolts 80 function as support members. To do. Since the intermediate plate 51 is supported by the bolts 80, the intermediate plate 51 is suppressed from moving in the direction orthogonal to the thickness direction. Further, since the bolts 80 are inserted into the first end plates 61, even if a load is applied to each bolt 80 from the intermediate plate 51, the movement of the bolts 80 is restricted by the first end plate 61. Therefore, the movement of the intermediate plate 51 is suppressed by restricting the movement of the bolt 80.

When the elastic member 31 is elastically deformed and a moving force in a direction perpendicular to the thickness direction acts on the intermediate plate 51, a load is applied to each bolt 80 from the intermediate plate 51. The load concentrates on the part to be done. Since the cylindrical portion 83 has higher rigidity than the screw portion 84, the bolt 80 is disposed so that the cylindrical portion 83 extends from the first end plate 61 to a position beyond the intermediate plate 51, thereby suppressing damage to the bolt 80. can do.

When the bolts 80 are inserted into the

end plates

61 and 62, the intermediate plate 51, and the plurality of battery holders 20, the bolts 80 are inserted into the small holes 71 without the positioning plate 70 being fixed to the plate base 63 of the first end plate 61. Is inserted. And after inserting the volt | bolt 80 in the small hole 71, each positioning plate 70 is fixed with the two screws S1.

The diameters of the first bolt holes 66 and 67 of the first end plate 61 are larger than the minimum diameter necessary for inserting the cylindrical portion 83 of the bolt 80. When the

end plates

61 and 62, the intermediate plate 51, and the plurality of battery holders 20 are arranged, the position of the bolt 80 is shifted due to the dimensional tolerance of these components. In order to allow this deviation, the diameters of the first bolt holes 66 and 67 of the first end plate 61 are made relatively large, so that the bolt 80 can move in the radial direction in the first bolt holes 66 and 67. However, if the radial movement of the bolt 80 in the first bolt holes 66 and 67 is allowed, the bolt 80 moves in the first bolt holes 66 and 67 when the elastic member 31 is elastically deformed in a direction perpendicular to the thickness direction. There is a possibility that the intermediate plate 51 moves in a direction perpendicular to the thickness direction. For this reason, the bolt 80 inserted into the first bolt holes 66 and 67 is further inserted into the small hole 71, and the radial movement of the bolt 80 in the first bolt holes 66 and 67 is restricted by the small hole 71. . Since the diameter of the fixing hole 72 of the positioning plate 70 is larger than the diameter of the screw hole 68, each positioning plate 70 can be positioned with respect to the first end plate 61 according to the position of the corresponding bolt 80. For this reason, the positioning plate 70 can be fixed to the first end plate 61 in a state where the bolt 80 is inserted into the small hole 71 even if the position of the bolt 80 is shifted due to the dimensional tolerance of the constituent members of the battery module 10. . The position of the bolt 80 with respect to the first end plate 61 is fixed by the small hole 71.

The intermediate plate 51 is fixed to the first cover member 91. When the plurality of battery cells 11 expand and the elastic member 31 elastically deforms, the battery cell 11 moves toward the elastic member 31. In particular, the movement amount of the first battery cell 11 a adjacent to the elastic member 31 is the largest among the movement amounts of the plurality of battery cells 11, and stress is generated in the bus bar 102 fixed to the first cover member 91. Since the first cover member 91 moves integrally with the battery cell 11 by the movement of the intermediate plate 51 as the battery cell 11 moves in the arrangement direction, the occurrence of stress on the bus bar 102 is suppressed. .

Therefore, according to the above embodiment, the following effects can be obtained.
(1) An intermediate plate 51 is provided between the elastic member 31 and the first battery cell 11 a, and a load in a direction orthogonal to the arrangement direction of the battery cells 11 is applied to the battery cell 11 with the elastic deformation of the elastic member 31. I am trying not to. The intermediate plate 51 is supported by the support member held by the first end plate 61, that is, the bolt 80, so that the intermediate plate 51 moves in a direction perpendicular to the arrangement direction of the battery cells 11 along with the elastic deformation of the elastic member 31. Is suppressed. For this reason, even if the elastic member 31 is elastically deformed in a direction orthogonal to the arrangement direction of the battery cells 11, the battery module 10 is not easily deformed. Therefore, the connection state between the battery cells 11 is maintained, and breakage of members constituting the battery module 10 is suppressed.

(2) The intermediate plate 51 is supported by a bolt 80 that applies a restraining load to the first end plate 61 and the second end plate 62. For this reason, it is not necessary to separately provide a member for supporting the intermediate plate 51, and an increase in the number of parts is suppressed.

(3) The first end plate 61 has a positioning plate 70. The diameter of the small hole 71 of the positioning plate 70 is smaller than the diameter of the first bolt holes 66 and 67 of the first end plate 61. For this reason, even when the diameter of the first bolt holes 66 and 67 of the first end plate 61 is relatively large in consideration of the dimensional tolerance of the members constituting the battery module 10, the bolts 80 are formed by the small holes 71. Can be restricted.

(4) The cylindrical portion 83 of the bolt 80 extends from the first end plate 61 to a position beyond the intermediate plate 51. When the elastic member 31 is elastically deformed in a direction orthogonal to the arrangement direction of the battery cells 11, a load is applied from the intermediate plate 51 to the bolt 80. In the shaft portion 82, the rigidity of the cylindrical portion 83 is higher than the rigidity of the screw portion 84, so that a portion to which a load from the intermediate plate 51 is easily applied is formed as the cylindrical portion 83, thereby suppressing the breakage of the bolt 80. can do.

(5) The diameter of the second bolt holes 76 and 78 of the second end plate 62 is smaller than the diameter of the cylindrical portion 83 of the bolt 80. For this reason, the bolt 80 cannot be inserted into the battery module 10 from the second end plate 62 toward the first end plate 61. Accordingly, the bolt 80 is prevented from being inserted from the wrong direction, and the bolt 80 is prevented from being arranged so that the screw portion 84 extends from the first end plate 61 to a position beyond the intermediate plate 51.

(6) The battery cells 11 are bonded to each other. Therefore, the battery cells 11 are not easily displaced from each other, and deformation of the battery module 10 is suppressed.
(7) The intermediate plate 51 is fixed to the first cover member 91. For this reason, when the plurality of battery cells 11 expand, the intermediate plate 51 can move integrally with the first cover member 91, and the stress on the bus bar 102 can be suppressed. Therefore, in addition to suppressing the deformation of the battery module 10 due to the elastic deformation of the elastic member 31 in the direction orthogonal to the arrangement direction of the battery cells 11, the deformation of the bus bar 102 can be suppressed.

In addition, you may change embodiment as follows.
The positioning plate 70 may not be fixed to the first end plate 61. In this case, the diameter of the first bolt holes 66 and 67 of the first end plate 61 is made smaller than that of the above embodiment, and the distance that the bolt 80 can move in the first bolt holes 66 and 67 in the radial direction is reduced. Is preferred.

The bolt 80 may be arranged so that the screw portion 84 extends from the first end plate 61 to a position beyond the intermediate plate 51. In this case, it is preferable that the screw portion 84 has such a rigidity that the bolt 80 is not damaged by the load applied from the intermediate plate 51 to the bolt 80.

O The diameters of the second bolt holes 76 and 78 of the second end plate 62 may be larger than the diameter of the cylindrical portion 83. In this case, the diameter of the cylindrical portion 83 and the diameter of the screw portion 84 may be the same. In this case, since the bolt 80 can be inserted into the battery module 10 from the second end plate 62 toward the first end plate 61, when the cylindrical portion 83 is to be inserted into the first end plate 61, It is desirable to prevent the bolt 80 from being inserted from the wrong direction by other configurations.

The battery cell 11 may not be bonded to the heat transfer plate 41.
The heat transfer plate 41 may not be provided. In this case, the adjacent battery cells 11 are bonded together by the adhesive sheet 32.

The intermediate plate 51 may be supported by a support member different from the bolt 80 held by the first end plate 61. For example, a pin extending from the intermediate plate 51 toward the first end plate 61 may be fixed or held on the first end plate 61, and the intermediate plate 51 may be supported by pins held on the first end plate 61.

The intermediate plate 51 may not be connected to the first cover member 91.
The battery cell 11 may not be held by the battery holder 20.
The intermediate plate 51 and the elastic member 31 are not only provided between the first end plate 61 and the first battery cell 11a, but further provided between the second end plate 62 and the second battery cell 11b. Also good. In this case, the deformation of the battery module 10 can be suppressed by supporting the intermediate plate 51 provided between the second end plate 62 and the second battery cell 11b with the bolts 80.

○ The elastic member 31 may be a spring or the like.

Claims

A plurality of battery cells arranged in a row;
A first end plate and a second end plate that sandwich the plurality of battery cells from both sides in the arrangement direction;
An intermediate plate that is provided between the first end plate and the battery cells adjacent to the first end plate, and is configured to move in the arrangement direction with expansion of the plurality of battery cells;
An elastic member provided between the intermediate plate and the first end plate and configured to be elastically deformed by being pressed by the movement of the intermediate plate accompanying expansion of the battery cell;
A battery module comprising: a support member that is held by the first end plate and supports the intermediate plate from a direction orthogonal to the arrangement direction.
The support member is a bolt, and the bolt passes through the first end plate, the second end plate, and the intermediate plate, and a plurality of bolts with respect to the first end plate and the second end plate. Apply a load so as to restrain the battery cells from both sides in the arrangement direction,
2. The battery module according to claim 1, wherein the first end plate, the second end plate, and the intermediate plate each have a bolt hole through which the bolt is inserted in the arrangement direction.
A positioning plate fixed to the first end plate and determining a position of the bolt with respect to the first end plate;
The battery module according to claim 2, wherein the positioning plate has a small hole through which the bolt is inserted, and the small hole has a smaller diameter than the bolt hole of the first end plate.
An elastic member is not provided between the second end plate and the battery cell adjacent to the second end plate, and the first and second end plates are configured so that a plurality of the battery cells are arranged from both sides in the arrangement direction. Pinching,
The bolt has a head, a cylindrical portion extending from the head, and a screw portion extending from the cylindrical portion,
4. The battery according to claim 2, wherein the head is disposed on a side corresponding to the first end plate, and the cylindrical portion extends from the first end plate to a position beyond the intermediate plate. module.
The screw portion has a diameter smaller than the diameter of the cylindrical portion;
The battery module according to claim 4, wherein the bolt hole of the second end plate has a diameter smaller than a diameter of the cylindrical portion and larger than a diameter of the screw portion.
The battery module according to any one of claims 1 to 5, wherein the battery cells adjacent in the arrangement direction are bonded to each other.