Battery module

Abstract

This battery module (100) comprises: a battery cell (110); and a housing body (200) that houses the battery cell (110). The housing body (200) has a first metal part (212) and a first refractory part (216) positioned at least partially between the first metal part (212) and the battery cell (110).

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 battery cells and a housing that houses the battery cells.

[0003] Patent Document 1 describes an example of a battery module. The battery module includes a plurality of battery cells, a module frame that houses the plurality of battery cells, and end plates that are connected to the module frame. The end plates have a main body made of a metal material and an insulating coating that covers the entire surface of the main body.

[0004] Patent Document 2 describes an example of a battery module. The battery module includes a plurality of battery cells, a module frame that houses the plurality of battery cells, a bus bar frame positioned between a side surface of the module frame and the plurality of battery cells, and an insulating plate positioned between the side surface of the module frame and the bus bar frame.

[0005] Special table 2021-532543 publication Special table 2022-519234 publication

[0006] The housing that houses the battery cells may have a metal part such as a metal plate. To prevent a short circuit between the battery cell and the metal part, an electrically insulating resin part may be provided between the battery cell and the metal part. However, if abnormal heat is generated in the battery cell, the resin part may melt. If the resin part melts, it may become difficult to prevent a short circuit between the battery cell and the metal part.

[0007] An example of an object of the present invention is to prevent a short circuit between a battery cell and a housing when abnormal heat generation occurs in the battery cell. 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; and a housing that houses the battery cell, wherein the housing has a metal portion and a heat-resistant portion located at least partially between the metal portion and the battery cell. 2. The battery module described in 1., wherein the housing further has a resin portion, and the heat-resistant portion is located at least partially between the metal portion and the resin portion. 3. The battery module described in 2., wherein the metal portion and the resin portion are joined to each other with the resin portion at least partially penetrating the heat-resistant portion. 4. The battery module described in any one of 1. to 3., wherein the heat-resistant portion covers at least a portion of an edge of the metal portion. 5. The battery module described in 4., wherein the metal portion defines a notch that includes at least the portion of the edge of the metal portion, and wherein a space defined by the notch at least partially overlaps a conductor electrically connected to the battery cell. 6. The heat-resistant portion includes silicon fiber. 7. The battery module according to any one of 1. to 6., wherein the battery cell has a tab, and the heat-resistant portion is at least partially located between the metal portion and the tab.

[0009] According to the above aspect of the present invention, it is possible to prevent a short circuit between the battery cell and the container when abnormal heat generation occurs in the battery cell.

[0010] 2 is an exploded top perspective view of a battery module according to an embodiment of the present invention, a front perspective view of a first plate and a second plate according to an embodiment of the present invention, and a schematic cross-sectional view of the battery module according to an embodiment of the present invention taken along line AA of FIG.

[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 purpose of explanation, the X, Y, and Z directions are shown in each figure. 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 , and a housing 200 .

[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 conductor 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 includes 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 a conductor 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 installing 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 the +Y side of the stack of battery cells 110, and the second bus bar 145 is arranged on the +X side and the −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. A thermally conductive adhesive 270 is disposed between the +Z side surface of the sixth plate 260 and the −Z side surface of the stack of battery cells 110. Therefore, heat generated from the stack of battery cells 110 can be dissipated downwards in the battery module 100 through the thermally conductive adhesive 270.

[0033] Fig. 2 is a front perspective view of a first plate 210 and a second plate 220 according to the embodiment. Fig. 3 is a schematic cross-sectional view taken along line AA in Fig. 2.

[0034] The first plate 210 according to the embodiment will be described with reference to FIGS. 2 and 3, and also with reference to FIG. 1 as necessary.

[0035] The first plate 210 includes a first metal portion 212, a first resin portion 214, and a first fire-resistant portion 216. The first metal portion 212 defines a first notch 212a1 and a second notch 212a2. The first resin portion 214 includes a first resin plate 214a and a plurality of first resin protrusions 214b. The first fire-resistant portion 216 includes a first fire-resistant sheet 216a, a first fire-resistant extending sheet 216b1, and a second fire-resistant extending sheet 216b2.

[0036] The first metal portion 212 is made of a metal such as aluminum or stainless steel. The rigidity of the first metal portion 212 can be made higher than the rigidity of resin. Therefore, when the first plate 210 has the first metal portion 212, the strength of the first plate 210 can be improved compared to when the first plate 210 does not have the first metal portion 212 and is made of only resin.

[0037] The first metal portion 212 is a metal plate having a thickness substantially parallel to the X direction. Specifically, the first metal portion 212 has a substantially rectangular shape with a pair of long sides substantially parallel to the Y direction and a pair of short sides substantially parallel to the Z direction, excluding the first notch 212a1 and the second notch 212a2.

[0038] As shown in Fig. 2 , the first notch 212a1 is located on the +Y side of the long side on the +Z side of the first metal portion 212. As shown in Figs. 1 and 2 , the space defined by the first notch 212a1 and the first bus bar 135 at least partially overlap in the X direction. The first bus bar 135 is a conductor electrically connected to the battery cell 110. Therefore, electrical insulation between the first metal portion 212 and the first bus bar 135 can be ensured compared to when the first notch 212a1 is not defined in the first metal portion 212.

[0039] As shown in Fig. 2, the second notch 212a2 is located on the -Y side of the long side on the +Z side of the first metal portion 212. As shown in Figs. 1 and 2, the space defined by the second notch 212a2 and the first connector 134 at least partially overlap in the X direction. The first connector 134 is a conductor electrically connected to the battery cell 110. Therefore, electrical insulation between the first metal portion 212 and the first connector 134 can be ensured compared to when the first metal portion 212 does not define the second notch 212a2.

[0040] The first metal portion 212 may define a notch instead of or in addition to the first notch 212a1 and the second notch 212a2. The space defined by the notch and the conductor electrically connected to the battery cell 110 may at least partially overlap in the X direction. When the space and the conductor at least partially overlap in the X direction, electrical insulation between the first metal portion 212 and the conductor can be ensured, compared to when the first metal portion 212 does not define the notch.

[0041] The first resin portion 214 is made of a resin such as polypropylene (PP).

[0042] The first resin plate 214a has a thickness that is approximately parallel to the X direction. Specifically, the first resin plate 214a has a substantially rectangular shape with a pair of long sides that are approximately parallel to the Y direction and a pair of short sides that are approximately parallel to the Z direction.

[0043] The first resin plate 214a has electrical insulation properties. The first resin plate 214a covers substantially the entire surface of the −X side of the first metal portion 212. Therefore, in the X direction, the first resin plate 214a is at least partially located between the −X side surface of the first metal portion 212 and the +X side surfaces of the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135. Therefore, the first resin plate 214a can suppress short circuits between the first metal portion 212 and the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135.

[0044] The plurality of first resin protrusions 214b are provided on the +X side surface of the first resin plate 214a. For example, the first resin plate 214a and the plurality of first resin protrusions 214b are integrally formed by resin molding. The first metal part 212 and the first resin plate 214a are joined to each other by thermally caulking the plurality of first resin protrusions 214b, with a first fire-resistant sheet 216a (described later) at least partially disposed between the -X side surface of the first metal part 212 and the +X side surface of the first resin plate 214a. Specifically, when the first metal part 212 and the first resin plate 214a are joined to each other, each of the first resin protrusions 214b passes through a through-hole provided in the first fire-resistant sheet 216a and a through-hole provided in the first metal part 212 in the X direction. The dimension of the +X side end of each first resin protrusion 214b in the direction perpendicular to the X direction is larger than the dimension of the through hole provided in the first metal part 212 in the direction perpendicular to the X direction by heat caulking the +X side end of each first resin protrusion 214b. Therefore, the first metal part 212 and the first resin plate 214a are joined to each other in a state where the first metal part 212 does not come out of the first resin plate 214a toward the +X side. However, the method of joining the first metal part 212 and the first resin plate 214a is not limited to heat caulking the +X side end of each first resin part 214.

[0045] The formability of the first resin portion 214 is higher than the formability of the first fire-resistant portion 216. Therefore, in the embodiment, the degree of freedom in the shape of the −X side of the first plate 210 can be improved compared to when the first plate 210 does not include the first resin portion 214. However, the first plate 210 may include the first metal portion 212 and the first fire-resistant portion 216 without including the first resin portion 214.

[0046] The first refractory portion 216 includes a refractory material such as silicon fiber.

[0047] The first fire-resistant sheet 216a has a thickness that is approximately parallel to the X direction. Specifically, the first resin plate 214a, excluding the first fire-resistant extending sheet 216b1 and the second fire-resistant extending sheet 216b2, has a substantially rectangular shape with a pair of long sides that are approximately parallel to the Y direction and a pair of short sides that are approximately parallel to the Z direction.

[0048] The first fire-resistant sheet 216a has electrical insulation properties. The first fire-resistant sheet 216a covers substantially the entire surface of the −X side of the first metal portion 212. Therefore, in the X direction, the first fire-resistant sheet 216a is at least partially located between the −X side surface of the first metal portion 212 and the +X side surfaces of the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135. Therefore, the first fire-resistant sheet 216a can prevent short circuits between the first metal portion 212 and the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135.

[0049] The first fire-resistant sheet 216a does not have to cover substantially the entire −X side of the first metal portion 212. For example, the first fire-resistant sheet 216a may partially cover portions of the −X side surface of the first metal portion 212 that overlap in the X direction with the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135. When the first fire-resistant sheet 216a partially covers these portions of the −X side surface of the first metal portion 212, the first fire-resistant sheet 216a can suppress short circuits between the first metal portion 212 and the +X side tab group 118, the first voltage detection terminal 132, and the first bus bar 135. When the first fire-resistant sheet 216a partially covers the -X side surface of the first metal part 212, the material cost of the first fire-resistant sheet 216a can be reduced compared to when the first fire-resistant sheet 216a covers almost the entire -X side surface of the first metal part 212.

[0050] As shown in FIG. 2 , the first fire-resistant extension sheet 216b1 is folded back toward the −Z side, with at least a portion of the first fire-resistant extension sheet 216b1 covering at least a portion of the edge of the first notch 212a1 of the first metal portion 212. In the example shown in FIG. 2 , the first fire-resistant extension sheet 216b1 covers the edge of the first notch 212a1 of the first metal portion 212 facing the +Z side. This ensures electrical insulation between the first metal portion 212 and the conductors arranged around the first notch 212a1, compared to when the first fire-resistant extension sheet 216b1 does not cover the edge of the first metal portion 212. For example, a connection bus bar (not shown) may be arranged around the first notch 212a1 to electrically connect the first bus bar 135 to a bus bar of an external device, such as another battery module. In the embodiment, even if the connection bus bar falls toward the edge of the first metal portion 212, the first fire-resistant extension sheet 216b1 can prevent a short circuit between the connection bus bar and the first metal portion 212.

[0051] As shown in FIG. 2 , the second fire-resistant extension sheet 216b2 is folded back toward the −Z side, with at least a portion of the second fire-resistant extension sheet 216b2 covering at least a portion of the edge of the second notch 212a2 of the first metal portion 212. In the example shown in FIG. 2 , the second fire-resistant extension sheet 216b2 covers the edge of the second notch 212a2 of the first metal portion 212 facing the +Z side. This ensures electrical insulation between the first metal portion 212 and the conductors arranged around the second notch 212a2, compared to when the second fire-resistant extension sheet 216b2 does not cover the edge of the first metal portion 212. For example, a harness (not shown) electrically connected to the first connector 134 may be arranged around the second notch 212a2. In the embodiment, even if the harness falls toward the edge of the first metal part 212, the second fire-resistant extension sheet 216b2 can prevent a short circuit between the harness and the first metal part 212.

[0052] In the embodiment, the first refractory portion 216 covers at least a portion of the edges of the first notch 212a1, the second notch 212a2, etc. of the first metal portion 212. However, the first refractory portion 216 may cover at least a portion of an edge of the first metal portion 212 that is different from the edge of the notch. For example, the first refractory portion 216 may cover at least a portion of the edge of the first metal portion 212 in a state in which the first metal portion 212 does not define a notch. When the first refractory portion 216 covers at least a portion of the edge of the first metal portion 212, electrical insulation between the first metal portion 212 and a conductor disposed around the portion of the edge of the first metal portion 212 that is covered by the first refractory portion 216 can be ensured, compared to when the first refractory portion 216 does not cover any portion of the edge of the first metal portion 212.

[0053] The first refractory portion 216 is a heat-resistant portion having relatively high heat resistance. For example, the electrical insulation of the first refractory portion 216 is maintained after the first refractory portion 216 is exposed to 800°C for 10 minutes, preferably after being exposed to 1000°C for 10 minutes. In the embodiment, even if abnormal heat generation occurs in the battery cell 110, the heat resistance of the first refractory portion 216 can make the first refractory portion 216 less likely to melt. Therefore, even if the first resin portion 214 melts due to abnormal heat generation in the battery cell 110, the first refractory portion 216 can make it less likely to melt. Therefore, even if the first resin portion 214 melts due to abnormal heat generation in the battery cell 110, the first refractory portion 216 can suppress short-circuiting between the first metal portion 212 and each of the +X-side tab group 118, the first voltage detection terminal 132, and the first bus bar 135.

[0054] In one example, the heat resistance of the first fire-resistant portion 216 is higher than the heat resistance of the first resin portion 214. If the heat resistance of the first fire-resistant portion 216 is higher than the heat resistance of the first resin portion 214, the first fire-resistant portion 216 can be made less likely to melt than the first resin portion 214 even if abnormal heat generation occurs in the battery cell 110.

[0055] The first fire-resistant portion 216 also has relatively high fire resistance. Fire resistance is determined by the time it takes for a flame to completely burn a certain component. The longer it takes for the flame to burn a component, the higher the fire resistance, and the shorter it takes for the flame to burn a component, the lower the fire resistance. In the embodiment, even if abnormal heat generation occurs in the battery cell 110, the fire resistance of the first fire-resistant portion 216 can make the first fire-resistant portion 216 less likely to melt. Therefore, even if the first resin portion 214 melts due to abnormal heat generation in the battery cell 110, the first fire-resistant portion 216 can make it less likely to melt. Therefore, even if the first resin portion 214 melts due to abnormal heat generation in the battery cell 110, the first fire-resistant portion 216 can suppress short-circuiting between the first metal portion 212 and each of the +X-side tab group 118, the first voltage detection terminal 132, and the first bus bar 135.

[0056] In one example, the fire resistance of the first fire-resistant portion 216 is higher than the fire resistance of the first resin portion 214. If the fire resistance of the first fire-resistant portion 216 is higher than the fire resistance of the first resin portion 214, the first fire-resistant portion 216 can be made less likely to melt than the first resin portion 214 even if abnormal heat generation occurs in the battery cell 110.

[0057] The first fire-resistant portion 216 may or may not have flame resistance. If the first fire-resistant portion 216 has flame resistance, the first fire-resistant portion 216 may melt without burning at a temperature higher than the heat resistance temperature of the first fire-resistant portion 216. If the first fire-resistant portion 216 does not have flame resistance, the first fire-resistant portion 216 may burn and melt at a temperature higher than the heat resistance temperature of the first fire-resistant portion 216.

[0058] 2 , the second plate 220, like the first plate 210, includes a second metal portion 222 and a second resin portion 224 that correspond to the first metal portion 212 and the first resin portion 214, respectively. Like the first plate 210, the second plate 220 includes a second fire-resistant portion (not shown) that corresponds to the first fire-resistant portion 216. Therefore, even if abnormal heat generation occurs in the battery cell 110, the second fire-resistant portion can suppress short-circuiting between the second metal portion 222 and each of the −X-side tab group 118, the second voltage detection terminal 142, and the second bus bar 145.

[0059] In the embodiment, the first plate 210 and the second plate 220 have been described as having a three-layer structure of a resin portion, a fire-resistant portion, and a metal portion. However, the third plate 230, the fourth plate 240, the fifth plate 250, and the sixth plate 260 may also have a three-layer structure of a resin portion, a fire-resistant portion, and a metal portion, similar to the first plate 210 and the second plate 220. When the fire-resistant portion of each plate is at least partially located between the metal portion of each plate and the battery cell 110, a short circuit between the battery cell 110 and the housing 200 when abnormal heat generation occurs in the battery cell 110 can be suppressed compared to when the fire-resistant portion is not provided on each plate. Furthermore, each plate may have a three-layer structure of a resin portion, a heat-resistant portion, and a metal portion. The heat-resistant portion may or may not be fire-resistant.

[0060] 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.

[0061] This application claims priority based on Japanese Patent Application No. 2023-172622, filed October 4, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0062] 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, 212 First metal part, 212a1 First notch, 212a2 Second notch, 214 First resin part, 214a First resin plate, 214b First resin protrusion, 216 First fire-resistant portion, 216a: First fire-resistant sheet, 216b1: First fire-resistant extension sheet, 216b2: Second fire-resistant extension sheet, 220: Second plate, 222: Second metal portion, 224: Second resin portion, 230: Third plate, 240: Fourth plate, 250: Fifth plate, 260: Sixth plate, 270: Thermally conductive adhesive

Claims

1. A battery module comprising: a battery cell; and a housing that houses the battery cell, the housing having a metal part and a heat-resistant part located at least partially between the metal part and the battery cell.

2. The battery module according to claim 1, wherein the container further has a resin part, and the heat-resistant part is at least partially located between the metal part and the resin part.

3. The battery module according to claim 2, wherein the metal portion and the resin portion are joined to each other with the resin portion at least partially penetrating the heat-resistant portion.

4. The battery module according to any one of claims 1 to 3, wherein the heat-resistant portion covers at least a portion of the edge of the metal portion.

5. The battery module described in claim 4, wherein the metal portion defines a notch including at least a portion of the edge of the metal portion, and a space defined by the notch at least partially overlaps a conductor electrically connected to the battery cell.

6. The battery module according to any one of claims 1 to 5, wherein the heat-resistant portion contains silicon fiber.

7. A battery module according to any one of claims 1 to 6, wherein the battery cells have tabs, and the heat-resistant portion is at least partially located between the metal portion and the tab.

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