Battery module

Abstract

A battery module (100) comprises: a battery cell (110); a housing (200) that houses the battery cell (110); an adhesive (300) at least some of which is positioned between the battery module (100) and the housing (200); and a first extension section (264) and an elastic member (400) that block at least some of the adhesive (300).

Description

Battery module

[0001] The present invention relates to a battery module.

[0002] In recent years, various battery modules have been developed. A battery module includes a plurality of battery cells stacked in a predetermined direction and a housing that houses the plurality of battery cells.

[0003] Patent Document 1 describes a battery module, which includes a thermally conductive adhesive provided on both the upper and lower surfaces of a plurality of battery cells.

[0004] Patent Document 2 describes a battery module in which a frame-shaped protrusion is provided on the main surface of a battery cell, and a filler is applied to the main surface of the battery cell within the frame-shaped protrusion.

[0005] JP 2020-523749 A, WO 2019 / 187043

[0006] An adhesive, such as a thermally conductive adhesive, may be at least partially positioned between the battery cell and the housing, and the adhesive may be required to be positioned with precision.

[0007] One object of the present invention is to position an adhesive with precision. Other objects of the present invention will become apparent from the description of this specification.

[0008] An aspect of the present invention is as follows: 1. A battery module comprising: a battery cell; a housing that houses the battery cell; an adhesive located at least partially between the battery cell and the housing; and a structure that blocks at least a portion of the adhesive. 2. The battery module described in 1., in which the structure includes an elastic material. 3. The battery module described in 2., in which the elastic material is located at least partially between the battery cell and the housing. 4. The battery module described in 2. or 3., in which, when the elastic material is compressed, the stress of the elastic material is equal to or greater than the pressure exerted by the adhesive before hardening on the elastic material. 5. The battery module described in any one of 1. to 4., in which predetermined portions of the housing are joined to each other, and the structure is located at least partially between the predetermined portions and the adhesive. 6. The battery module described in any one of 1. to 5., in which the adhesive is thermally conductive.

[0009] According to the above aspect of the present invention, the adhesive can be positioned with high precision.

[0010] 1 is a graph showing the relationship between the compressibility of the elastic material and the stress of the elastic material;

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, similar components are designated by similar reference numerals, and the description thereof will be omitted as appropriate.

[0012] FIG. 1 is an exploded top perspective view of a battery module 100 according to an embodiment.

[0013] For the sake of explanation, the X, Y, and Z directions are shown in FIG. 1 and FIG. 2 , which will be described later. The X direction indicates the front-to-rear direction of the battery module 100. The Y direction is perpendicular to the X direction. The Y direction indicates the left-to-right direction of the battery module 100. The Z direction is perpendicular to both the X and Y directions. The Z direction indicates the up-down direction of the battery module 100. The arrows pointing to the X direction, the Y direction, and the Z direction indicate the front, left, and up directions of the battery module 100, respectively. Hereinafter, as necessary, the tip side of an arrow indicating the X direction will be referred to as the +X side, the opposite side of the tip of the arrow indicating the X direction will be referred to as the −X side, the tip side of an arrow indicating the Y direction will be referred to as the +Y side, the opposite side of the tip of the arrow indicating the Y direction will be referred to as the −Y side, the tip side of an arrow indicating the Z direction will be referred to as the +Z side, and the opposite side of the tip of the arrow indicating the Z direction will be referred to as the −Z side. The relationship between the X direction, Y direction, and Z direction and the front-rear direction, left-right direction, and up-down direction of the battery module 100 is not limited to the above example.

[0014] The battery module 100 includes a plurality of battery cells 110 , a plurality of compression pads 120 , a first voltage detection device 130 , a second voltage detection device 140 , a container 200 , an adhesive 300 , and a pair of elastic members 400 .

[0015] The multiple battery cells 110 and the multiple compression pads 120 are stacked alternately in the Y direction. Each compression pad 120 is arranged between adjacent battery cells 110 in the Y direction and on both sides of the multiple battery cells 110 in the Y direction. Hereinafter, as necessary, the multiple battery cells 110 and the multiple compression pads 120 stacked alternately in the Y direction will be referred to as a stack of battery cells 110. The dimension of each battery cell 110 in the X direction is the dimension in the longitudinal direction of each battery cell 110. The dimension of each battery cell 110 in the Z direction is the dimension in the lateral direction of each battery cell 110. The dimension of each battery cell 110 in the Y direction is the dimension in the thickness direction of each battery cell 110. The shape of each battery cell 110 is not limited to this example.

[0016] Each battery cell 110 includes a battery element (not shown), an exterior material 112, a positive electrode tab 114, and a negative electrode tab 116. In one example, the battery element includes a plurality of positive electrodes and a plurality of negative electrodes (not shown) stacked alternately in the Y direction, and a separator (not shown) positioned between adjacent positive electrodes and negative electrodes in the Y direction. The exterior material 112 seals the battery element and an electrolyte (not shown). The positive electrode tab 114 is electrically connected to the positive electrode of the battery element. The positive electrode tab 114 is pulled out from one of both sides of the exterior material 112 in the X direction. The negative electrode tab 116 is electrically connected to the negative electrode of the battery element. The negative electrode tab 116 is pulled out from the other side of both sides of the exterior material 112 in the X direction. However, the structure of each battery cell 110 is not limited to this example.

[0017] Each battery cell 110 may be an all-solid-state battery. In an all-solid-state battery, a solid electrolyte layer is provided in a portion corresponding to a separator. An all-solid-state battery does not contain an electrolyte solution. Unless otherwise specified, the following description will be given assuming that each battery cell 110 is a battery cell containing an electrolyte solution.

[0018] The multiple battery cells 110 are electrically connected in a series-parallel combination. Specifically, cell groups including at least two battery cells 110 adjacent to each other in the Y direction and connected in parallel are stacked in the Y direction and connected in series. On the +X side of the stack of battery cells 110, a positive electrode tab 114 drawn from a battery cell 110 of one cell group connected in parallel and a negative electrode tab 116 drawn from a battery cell 110 of another cell group connected in parallel are electrically connected to each other, forming a tab group 118 including the positive electrode tab 114 and the negative electrode tab 116. The positive electrode tab 114 and the negative electrode tab 116 in the tab group 118 are joined to each other by, for example, laser welding. A tab group 118 is also located on the −X side of the stack of battery cells 110. Thus, multiple cell groups are connected in series from the cell group located at one end of the stack of battery cells 110 in the Y direction to the cell group located at the other end of the stack of battery cells 110 in the Y direction. Hereinafter, as necessary, the tab group 118 located on the +X side of the stack of battery cells 110 will be referred to as the +X side tab group 118, and the tab group 118 located on the -X side of the stack of battery cells 110 will be referred to as the -X side tab group 118.

[0019] The electrical connection of the plurality of battery cells 110 is not limited to the above example. For example, a stack of battery cells 110 may be configured by connecting single battery cells 110 in series.

[0020] The first voltage detection device 130 detects the voltages of the plurality of +X side tab groups 118. The first voltage detection device 130 includes a first protector 131, a plurality of first voltage detection terminals 132, a plurality of first voltage detection lines 133, a first connector 134, and a first bus bar 135.

[0021] The first protector 131 covers the +X side portion of the stack of battery cells 110. The first protector 131 is, for example, an insulator such as resin. The first protector 131 defines a plurality of first openings 131a. Each of the plurality of +X side tab groups 118 is exposed toward the +X side through each of the plurality of first openings 131a.

[0022] Each of the multiple first voltage detection terminals 132 is located on the +X side of each of the multiple +X side tab groups 118. Each first voltage detection terminal 132 is made of a conductive material such as metal. The -X side surface of each first voltage detection terminal 132 and the +X side surface of each +X side tab group 118 are joined to each other by a joining method such as laser welding. Therefore, each first voltage detection terminal 132 and each +X side tab group 118 are electrically connected to each other. Therefore, the first voltage detection device 130 can detect the voltage of each +X side tab group 118 using each first voltage detection terminal 132. The multiple first voltage detection terminals 132 are held together by a first protector 131. Therefore, by placing the first protector 131 at an appropriate position relative to the stack of battery cells 110, each of the multiple first voltage detection terminals 132 can be positioned appropriately relative to each of the multiple +X side tab groups 118.

[0023] One end of each first voltage detection line 133 is electrically connected to each first voltage detection terminal 132. The other end of each first voltage detection line 133 is electrically connected to each first connector 134. Thus, the first voltage detection terminals 132 and the first connectors 134 are electrically connected to each other via the first voltage detection lines 133. Each first voltage detection line 133 is routed between one end of the first voltage detection line 133 and the other end of the first voltage detection line 133 via the first protector 131.

[0024] The first bus bar 135 is disposed at the end portion on the +Y side of the first protector 131. The first bus bar 135 is electrically connected to the positive electrode tab 114 drawn out to the +X side from the battery cell 110 of the cell group located at the end portion on the +Y side of the stack of battery cells 110. The first bus bar 135 functions as an external terminal for electrically connecting the battery module 100 to an external device such as another battery module.

[0025] The second voltage detection device 140 detects the voltages of the plurality of −X side tab groups 118. The second voltage detection device 140 has a second protector 141, a plurality of second voltage detection terminals 142, a plurality of second voltage detection lines 143, a second connector 144, and a second bus bar 145.

[0026] The second protector 141 covers the -X side portion of the stack of battery cells 110. The second protector 141 is, for example, an insulator such as resin. The second protector 141 defines a plurality of second openings 141a. Each of the plurality of -X side tab groups 118 is exposed toward the -X side through each of the plurality of second openings 141a.

[0027] Each of the multiple second voltage detection terminals 142 is located on the -X side of each of the multiple -X side tab groups 118. Each second voltage detection terminal 142 is made of a conductive material such as metal. The +X side surface of each second voltage detection terminal 142 and the -X side surface of each -X side tab group 118 are joined to each other by a joining method such as laser welding. Therefore, each second voltage detection terminal 142 and each -X side tab group 118 are electrically connected to each other. Therefore, the second voltage detection device 140 can detect the voltage of each -X side tab group 118 using each second voltage detection terminal 142. The multiple second voltage detection terminals 142 are held together by a second protector 141. Therefore, by placing the second protector 141 at an appropriate position relative to the stack of battery cells 110, each of the multiple second voltage detection terminals 142 can be positioned appropriately relative to each of the multiple -X side tab groups 118.

[0028] One end of each second voltage detection line 143 is electrically connected to each second voltage detection terminal 142. The other end of each second voltage detection line 143 is electrically connected to each second connector 144. Thus, the second voltage detection terminals 142 and the second connector 144 are electrically connected to each other via the second voltage detection lines 143. Each second voltage detection line 143 is routed between one end of the second voltage detection line 143 and the other end of the second voltage detection line 143 via the second protector 141.

[0029] The second bus bar 145 is disposed at the end portion on the -Y side of the second protector 141. The second bus bar 145 is electrically connected to the negative electrode tab 116 that is drawn out to the -X side from the battery cell 110 of the cell group located at the end portion on the -Y side of the stack of battery cells 110. The second bus bar 145 functions as an external terminal for electrically connecting the battery module 100 to an external device such as another battery module.

[0030] 1 , the positive electrode tab 114 at the end of a group of multiple cells connected in series is drawn out toward the +X side from the battery cell 110 of the cell group located at the end portion on the +Y side of the stack of battery cells 110, and the negative electrode tab 116 at the end of a group of multiple cells connected in series is drawn out toward the −X side from the battery cell 110 of the cell group located at the end portion on the −Y side of the stack of battery cells 110. Thus, the first bus bar 135 is disposed on the +X side and +Y side of the stack of battery cells 110, and the second bus bar 145 is disposed on the −X side and −Y side of the stack of battery cells 110. However, the arrangement of the positive electrode tab 114 and the negative electrode tab 116 at the end of a group of multiple cells connected in series may differ depending on the number of battery cells 110 included in the stack of battery cells 110. For example, there may be a case where the positive electrode tab 114 at the end of a group of multiple cells connected in series is pulled out toward the +X side from the battery cell 110 of the cell group located at the end portion on the +Y side of the stack of battery cells 110, and the negative electrode tab 116 at the end of a group of multiple cells connected in series is pulled out toward the +X side from the battery cell 110 of the cell group located at the end portion on the -Y side of the stack of battery cells 110. In this case, the first bus bar 135 is arranged on the +X side and +Y side of the stack of battery cells 110, and the second bus bar 145 is arranged on the -X side and -Y side of the stack of battery cells 110.

[0031] The container 200 includes a first plate 210 , a second plate 220 , a third plate 230 , a fourth plate 240 , a fifth plate 250 , and a sixth plate 260 .

[0032] The first plate 210 covers the +X side portion of the stack of battery cells 110 and the +X side portion of the first voltage detection device 130. The second plate 220 covers the -X side portion of the stack of battery cells 110 and the -X side portion of the second voltage detection device 140. The third plate 230 covers the +Y side portion of the stack of battery cells 110. The fourth plate 240 covers the -Y side portion of the stack of battery cells 110. The fifth plate 250 covers the +Z side portion of the stack of battery cells 110. The sixth plate 260 covers the -Z side portion of the stack of battery cells 110.

[0033] 2 is a perspective view of one battery cell 110 according to the embodiment, a sixth plate 260, an adhesive 300, and a pair of elastic members 400. In FIG. 2, one battery cell 110 located at the end of the stack of battery cells 110 on the −Y side is illustrated.

[0034] The sixth plate 260, the adhesive 300, and the pair of elastic members 400 will be described with reference to FIG. 2 and, if necessary, with reference to FIG.

[0035] The sixth plate 260 is a metal plate such as an aluminum plate. The sixth plate 260 includes a plate portion 262, a pair of first extending portions 264, and a pair of second extending portions 266. When viewed from the Z direction, the plate portion 262 has a substantially square or rectangular plate shape with a pair of sides parallel to the X direction and another pair of sides parallel to the Y direction. The pair of first extending portions 264 are bent toward the +Z side from both ends of the plate portion 262 in the X direction. The pair of first extending portions 264 extend in the Y direction. The pair of second extending portions 266 are bent toward both outer sides of the plate portion 262 in the X direction from the +Z side ends of the pair of first extending portions 264. The pair of second extending portions 266 extend in the Y direction. When viewed from the Y direction, the plate portion 262 and the pair of first extending portions 264 define a concave shape that is open toward the +Z side.

[0036] The adhesive 300 has thermal conductivity. The adhesive 300 is, for example, a thermally conductive adhesive such as a silicone adhesive or a urethane adhesive. The adhesive 300 is at least partially located between the -Z side surface of the stack of battery cells 110 and the +Z side surface of the plate portion 262 in the Z direction. Therefore, heat generated from the stack of battery cells 110 can be released toward the plate portion 262 via the adhesive 300. However, the adhesive 300 does not have to have thermal conductivity.

[0037] Each elastic material 400 is an elastically deformable material. In one example, each elastic material 400 is a porous material such as a sponge. When the elastic material 400 is a porous material, pores exist on the surface and at least a portion of the interior of the elastic material 400. The elastic material 400 may be rubber. In the embodiment, each elastic material 400 in an uncompressed state has a substantially square pillar shape extending in the X direction. However, the shape of the elastic material 400 in an uncompressed state is not limited to the shape described in the embodiment.

[0038] The pair of first extending portions 264 are located on both sides of the adhesive 300 in the X direction. Therefore, when viewed from the Z direction, the pair of first extending portions 264 are located at least partially around the periphery of the adhesive 300. Therefore, the pair of first extending portions 264 are structured to block both ends of the adhesive 300 in the X direction.

[0039] The pair of elastic members 400 are located on both sides of the adhesive 300 in the Y direction. Therefore, when viewed from the Z direction, each elastic member 400 is located at least partially around the periphery of the adhesive 300. Therefore, the pair of elastic members 400 are structured to block both ends of the adhesive 300 in the Y direction.

[0040] Hereinafter, as needed, the battery cell 110 located at the end on the -Y side of the stack of battery cells 110 will be referred to as the -Y-side battery cell 110, and the battery cell 110 located at the end on the +Y side of the stack of battery cells 110 will be referred to as the +Y-side battery cell 110. Hereinafter, as needed, the first extension portion 264 located on the -X side of the pair of first extension portions 264 will be referred to as the -X-side first extension portion 264, and the first extension portion 264 located on the +X side of the pair of first extension portions 264 will be referred to as the +X-side first extension portion 264. Hereinafter, as needed, the second extension portion 266 located on the -X side of the pair of second extension portions 266 will be referred to as the -X-side second extension portion 266, and the second extension portion 266 located on the +X side of the pair of second extension portions 266 will be referred to as the +X-side second extension portion 266. Hereinafter, as necessary, the elastic material 400 located on the -Y side of the pair of elastic materials 400 will be referred to as the -Y side elastic material 400, and the elastic material 400 located on the +Y side of the pair of elastic materials 400 will be referred to as the +Y side elastic material 400.

[0041] The adhesive 300 is formed by curing adhesive applied in a liquid or gel state to the +Z side surface of the plate portion 262. Hereinafter, the adhesive 300 in a liquid or gel state before curing is referred to as the uncured adhesive. The uncured adhesive is formed into the adhesive 300 as follows. First, the uncured adhesive is applied to the +Z side surface of the plate portion 262 between the pair of first extension portions 264 in the X direction and between the pair of elastic members 400 in the Y direction. Next, a stack of battery cells 110 is placed on the +Z side surface of the plate portion 262 via the uncured adhesive and the pair of elastic members 400. The load on the stack of battery cells 110 in the Z direction causes the uncured adhesive to spread in a direction perpendicular to the Z direction. Even if the uncured adhesive spreads to the +X side and the −X side, the pair of first extension portions 264 can block both ends of the uncured adhesive in the X direction. Even if the uncured adhesive spreads to the +Y side and the -Y side, the pair of elastic members 400 can block both ends of the uncured adhesive in the Y direction. Therefore, compared to a state in which the pair of first extending portions 264 and the pair of elastic members 400 are not provided, the uncured adhesive, i.e., the adhesive 300, can be positioned with higher precision. Next, the uncured adhesive is cured to form the uncured adhesive into the adhesive 300. The method for curing the uncured adhesive is not particularly limited, and examples thereof include drying, heating, and light irradiation.

[0042] 1 and 2, unevenness is formed on the +Z side surface of the adhesive 300. The unevenness on the +Z side surface of the adhesive 300 is formed by the transfer of uncured adhesive from the −Z side surface of the stack of battery cells 110 to the +Z side surface due to the load on the uncured adhesive of the stack of battery cells 110.

[0043] In the embodiment, after adhesive 300 is formed on the +Z side surface of plate portion 262, the -Z side end of first plate 210 and the +Z side surface of +X side second extension portion 266 are joined to each other by a joining method such as laser welding, and the -Z side end of second plate 220 and the +Z side surface of -X side second extension portion 266 are joined to each other by a joining method such as laser welding. The +X side first extension portion 264 is at least partially located between the +Z side surface of +X side second extension portion 266 and the +X side end of adhesive 300. This prevents the +X side end of adhesive 300 from reaching the +Z side surface of +X side second extension portion 266. Therefore, it is possible to suppress poor bonding, such as poor welding, between the -Z side end of the first plate 210 and the +Z side surface of the +X side second extension portion 266, which is caused by the presence of at least a portion of the adhesive 300 on the +Z side surface of the +X side second extension portion 266. Similar to the +X side first extension portion 264, the -X side first extension portion 264 is at least partially located between the +Z side surface of the -X side second extension portion 266 and the -X side end of the adhesive 300. Therefore, it is possible to suppress poor bonding between the -Z side end of the second plate 220 and the +Z side surface of the -X side second extension portion 266, which is caused by the presence of at least a portion of the adhesive 300 on the +Z side surface of the -X side second extension portion 266.

[0044] In the embodiment, after adhesive 300 is formed on the +Z side surface of plate portion 262, the -Z side end of third plate 230 and the +Z side surface of the +Y side end of plate portion 262 are joined to each other by a joining method such as laser welding, and the -Z side end of fourth plate 240 and the +Z side surface of the -Y side end of plate portion 262 are joined to each other by a joining method such as laser welding. The +Y side elastic material 400 is at least partially located between the +Z side surface of the +Y side end of plate portion 262 and the +Y side end of adhesive 300. This prevents the +Y side end of adhesive 300 from reaching the +Z side surface of the +Y side end of plate portion 262. This prevents poor joining, such as poor welding, between the -Z side end of third plate 230 and the +Z side surface of the +Y side end of plate portion 262, due to the presence of at least a portion of adhesive 300 on the +Z side surface of the +Y side end of plate portion 262. Similar to the +Y-side elastic material 400, the -Y-side elastic material 400 is at least partially located between the +Z-side surface of the -Y-side end of plate portion 262 and the -Y-side end of adhesive 300. Therefore, poor bonding between the -Z-side end of fourth plate 240 and the +Z-side surface of the -Y-side end of plate portion 262, which is caused by the presence of at least a portion of adhesive 300 on the +Z-side surface of the -Y-side end of plate portion 262, can be suppressed.

[0045] As shown in FIG. 2 , the -Y-side elastic material 400 is at least partially located between the -Z-side surface of the -Y-side battery cell 110 and the +Z-side surface of the plate portion 262. Therefore, the -Y-side elastic material 400 is compressed in the Z direction by the -Z-side surface of the -Y-side battery cell 110 and the +Z-side surface of the plate portion 262. Therefore, stress in the Z direction is generated in the -Y-side elastic material 400. In this embodiment, the Z-direction stress of the -Y-side elastic material 400 is equal to or greater than the pressure exerted by the uncured resin on the -Y-side elastic material 400, preferably greater than the pressure exerted by the uncured resin on the -Y-side elastic material 400. Therefore, compared to when the Z-direction stress of the -Y-side elastic material 400 is less than the pressure exerted by the uncured resin on the -Y-side elastic material 400, it is possible to make it less likely for the -Y-side end of the uncured resin to protrude toward the -Y side from the gap between the -Z-side surface of the -Y-side battery cell 110 and the +Z-side surface of the -Y-side elastic material 400. However, the stress in the Z direction of the elastic material 400 on the -Y side may be less than the pressure that the uncured resin exerts on the -Y side elastic material 400. The same applies to the relationship between the stress in the Z direction of the elastic material 400 on the +Y side and the pressure that the uncured resin exerts on the elastic material 400 on the +Y side.

[0046] The Z-direction stress of the -Y-side elastic material 400 can be adjusted by the Z-direction compressibility of the -Y-side elastic material 400. Therefore, the Z-direction stress of the -Y-side elastic material 400 can be determined depending on the relationship between the Z-direction thickness of the -Y-side elastic material 400 in an uncompressed state and the Z-direction dimension of the gap between the -Z-side surface of the -Y-side battery cell 110 and the +Z-direction surface of the plate portion 262. The same applies to the Z-direction stress of the +Y-side elastic material 400. The pressure exerted by the uncured resin on the -Y-side elastic material 400 can be adjusted by the material of the uncured resin. The pressure exerted by the uncured resin on the -Y-side elastic material 400 may be constant regardless of the Z-direction compressibility of the uncured resin. The same applies to the pressure exerted by the uncured resin on the +Y-side elastic material 400.

[0047] The method of generating stress in the Z direction in the elastic material 400 is not limited to the method described in the embodiment. For example, the elastic material 400 may be compressed in the Z direction by a member other than the battery cell 110 and the +Z side surface of the plate portion 262. In this example, stress in the Z direction can also be generated in the elastic material 400.

[0048] In the embodiment, each elastic member 400 serves as a structure that blocks the adhesive 300. Additionally, each elastic member 400 is at least partially positioned between the −Z-side surface of the stack of battery cells 110 and the +Z-side surface of the plate portion 262. Therefore, compared to when each elastic member 400 is positioned offset from the stack of battery cells 110 as viewed in the Z direction, the elastic member 400 can be placed in a smaller space inside the housing 200. Additionally, when this structure is an elastic member 400, damage to the battery cells 110 due to contact with the structure can be reduced compared to when this structure is made of a relatively hard material such as a metal block or a resin block. In particular, when the elastic member 400 is a porous material such as sponge, damage to the battery cells 110 due to contact with the elastic member 400 can be reduced compared to when the elastic member 400 is made of a solid material such as rubber. However, when viewed in the Z direction, the elastic member 400 may be positioned offset from the stack of battery cells 110. The structure that blocks the adhesive 300 may be a relatively hard material such as a metal block or a resin block instead of or in addition to the elastic material 400 .

[0049] In the example shown in Figure 2, except for both ends of the -Y-side elastic material 400 in the X direction, approximately half of the -Y-side surface of the -Z-side battery cell 110 and the +Z-side surface of the -Y-side elastic material 400 are in contact with each other. Therefore, the -Z-side surface of the -Y-side battery cell 110 is partially in contact with the -Y-side elastic material 400 and partially in contact with the adhesive 300. Therefore, compared to when the -Z-side surface of the -Y-side battery cell 110 is in contact only with the elastic material 400 without contacting the adhesive 300, heat generated from the -Y-side battery cell 110 can be more easily released to the plate portion 262 via the adhesive 300. However, the -Z-side surface of the -Y-side battery cell 110 may be in contact only with the elastic material 400 without contacting the adhesive 300. Even when the -Z side surface of the -Y side battery cell 110 is not in contact with the adhesive 300, the heat generated from the -Y side battery cell 110 can be released from the fourth plate 240. The same applies to the -Z side surface of the +Y side battery cell 110.

[0050] In the example shown in FIG. 2 , the +X-side end of the -Y-side elastic material 400 protrudes toward the +X-side from the +X-side end of the -Z-side surface of the -Y-side battery cell 110. Therefore, compared to when the +X-side end of the -Y-side elastic material 400 is positioned offset toward the -X side with respect to the +X-side end of the -Z-side surface of the -Y-side battery cell 110, it is possible to prevent the adhesive 300 from protruding through the +X-side region of the -Z-side surface of the -Y-side battery cell 110. The -X-side end of the -Y-side elastic material 400 also protrudes toward the -X side from the -X-side end of the -Z-side surface of the -Y-side battery cell 110. Therefore, compared to when the -X-side end of the -Y-side elastic material 400 is positioned offset toward the +X side with respect to the -X-side end of the -Z-side surface of the -Y-side battery cell 110, it is possible to prevent the adhesive 300 from protruding through the -X-side region of the -Z-side surface of the -Y-side battery cell 110. The same applies to the +Y-side elastic material 400.

[0051] FIG. 3 is a graph showing the relationship between the compressibility of the elastic material 400 and the stress of the elastic material 400. In the graph shown in FIG. 3, the horizontal axis represents the Z-direction compressibility of the elastic material 400 (unit: %), and the vertical axis represents the Z-direction stress of the elastic material 400 (unit: kPa). The Z-direction compressibility of the elastic material 400 is the ratio of the Z-direction thickness of the elastic material 400 in a compressed state to the Z-direction thickness of the elastic material 400 in an uncompressed state. The uncompressed state refers to a state in which the elastic material 400 is disposed on the +Z side surface of the plate portion 262 and the +Z side surface of the elastic material 400 is not pressed. The Z-direction stress of the elastic material 400 is the Z-direction stress of the elastic material 400 in a compressed state. In the example shown in FIG. 3, the elastic material 400 is a sponge having pores.

[0052] 3, the stress in the Z direction of the elastic material 400 increases relatively slowly as the Z direction compression rate of the elastic material 400 increases when the Z direction compression rate of the elastic material 400 is between 40% and 80%, and increases relatively rapidly as the Z direction compression rate of the elastic material 400 increases when the Z direction compression rate of the elastic material 400 is 80% or higher. The reason why the increase in the Z direction stress of the elastic material 400 as the Z direction compression rate of the elastic material 400 increases relatively slowly when the Z direction compression rate of the elastic material 400 is between 40% and 80% is presumably because when the Z direction compression rate of the elastic material 400 is between 40% and 80%, the hollow portions inside the elastic material 400, i.e., the pores, are mainly crushed, and the compression of the elastic material 400 in the Z direction does not contribute much to the increase in the stress of the elastic material 400. The reason why the increase in the Z-direction stress of the elastic material 400 with an increase in the Z-direction compression rate of the elastic material 400 is relatively rapid when the Z-direction compression rate of the elastic material 400 is 80% or more is presumably because the solid portion inside the elastic material 400 is crushed when the Z-direction compression rate of the elastic material 400 is 80% or more.

[0053] The pressure that the uncured adhesive exerts on the elastic material 400 is approximately 50 kPa, regardless of the compression of the uncured adhesive in the Z direction. Therefore, when the compression rate of the elastic material 400 in the Z direction is approximately 90% or more, the stress in the Z direction of the elastic material 400 can be made equal to or greater than the pressure that the uncured adhesive exerts on the elastic material 400. Therefore, in an embodiment, the Z direction thickness of the elastic material 400 in an uncompressed state and the Z direction dimension of the gap between the −Z side surface of the battery cell 110 and the +Z side surface of the plate portion 262 can be determined so that the compression rate of the elastic material 400 in the Z direction is 90% or more.

[0054] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0055] In the embodiment, a structure including a pair of first extensions 264 and a pair of elastic members 400 blocks the adhesive 300 that is at least partially located between the −Z side surface of the stack of battery cells 110 and the +Z side surface of the sixth plate 260. However, a structure similar to the structure described in the embodiment can also be used to block other adhesive that is at least partially located between the battery cells 110 and the housing 200. For example, an adhesive may also be at least partially located between the +Z side surface of the stack of battery cells 110 and the −Z side surface of the fifth plate 250. A structure similar to the structure described in the embodiment may also be located at least partially around this adhesive. In this example, the structure blocks the adhesive that is at least partially located between the +Z side surface of the stack of battery cells 110 and the −Z side surface of the fifth plate 250.

[0056] This application claims priority based on Japanese Patent Application No. 2023-141440, filed on August 31, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0057] REFERENCE SIGNS LIST 100 Battery module, 110 Battery cell, 112 Exterior material, 114 Positive electrode tab, 116 Negative electrode tab, 118 Tab group, 120 Compression pad, 130 First voltage detection device, 131 First protector, 131a First opening, 132 First voltage detection terminal, 133 First voltage detection line, 134 First connector, 135 First bus bar, 140 Second voltage detection device, 141 Second protector, 141a Second opening, 142 Second voltage detection terminal, 143 Second voltage detection line, 144 Second connector, 145 Second bus bar, 200 Housing, 210 First plate, 220 Second plate, 230 Third plate, 240 Fourth plate, 250 Fifth plate, 260 Sixth plate, 262 Plate portion, 264 First extension portion, 266 Second extension portion, 300 adhesive, 400 elastic material

Claims

1. A battery module comprising: a battery cell; a housing that houses the battery cell; an adhesive that is at least partially located between the battery cell and the housing; and a structure that blocks at least a portion of the adhesive.

2. The battery module according to claim 1, wherein the structure comprises an elastic material.

3. The battery module according to claim 2, wherein the elastic material is at least partially located between the battery cells and the housing.

4. The battery module according to claim 2 or 3, wherein the stress of said elastic material in a compressed state is equal to or greater than the pressure that said adhesive before hardening exerts on said elastic material.

5. A battery module according to any one of claims 1 to 4, wherein predetermined portions of the container are joined to each other, and the structure is at least partially located between the predetermined portions and the adhesive.

6. The battery module according to any one of claims 1 to 5, wherein the adhesive has thermal conductivity.

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