Battery module

Abstract

To secure electrical insulation between a battery cell and an accommodation body.SOLUTION: A battery module 100 includes a battery cell 110 including a positive electrode tab 114 or a negative electrode tab 116, and an accommodation body 200 for accommodating the battery cell 110. The accommodation body 200 includes a first metal part 212 and a first resin part 214 existing at least partially between the battery cell 110 and the first metal part 212. The first resin part 214 includes a second resin protrusion 214c protruding toward a first voltage detection terminal 132 electrically connected to the positive electrode tab 114 or the negative electrode tab 116.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] 2. Description of the Related Art 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 pack. The battery pack includes a battery unit, a positive output terminal and a negative output terminal electrically connected to the battery unit, and a holder that holds the positive output terminal and the negative output terminal. The holder has an uneven surface between the positive output terminal and the negative output terminal.

[0004] Patent Document 2 describes an example of a fuel cell stack. The fuel cell stack includes a plurality of fuel cell power generation units arranged in a predetermined direction, a pair of terminal plates located on either side of the plurality of fuel cell power generation units in the predetermined direction, a pair of insulating sheets located on either side of the pair of terminal plates in the predetermined direction, and a pair of end plates located on either side of the pair of insulating sheets in the predetermined direction. Bolts pass through the plurality of fuel cell power generation units, the pair of terminal plates, the pair of insulating sheets, and the pair of end plates. The inner surface of the through hole through which the bolt passes in the insulating sheet is stepped. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-220391 A [Patent Document 2] JP 2020-170631 A Summary of the Invention [Problem to be solved by the invention]

[0006] The housing that houses the battery cells may have a conductive part such as a metal plate. Inside the housing, a conductive part such as a tab of the battery cell or a conductive member electrically connected to the tab may be provided. When the voltage between the conductive part of the housing and the conductive part inside the housing is relatively high, it may be difficult to suppress discharge such as creeping discharge and spatial discharge between the conductive part of the housing and the conductive part inside the housing. When it is difficult to suppress discharge between the conductive part of the housing and the conductive part inside the housing, it may be difficult to ensure electrical insulation between the battery cell and the housing.

[0007] One object of the present invention is to ensure electrical insulation between the battery cell and the housing. Other objects of the present invention will become apparent from the description herein. [Means for solving the problem]

[0008] 1. A battery cell having an output terminal; a housing that houses the battery cell; Equipped with the housing includes a first conductive portion and an insulating portion located at least partially between the battery cell and the first conductive portion; the insulating portion includes a projection that projects toward a second conductive portion that includes at least one of the output terminal and a conductive member electrically connected to the output terminal. 2. The battery module described in 1., wherein the protrusion protrudes toward a portion of the second conductive portion that is shifted toward the center of the second conductive portion relative to the end of the second conductive portion. 3. A battery module described in 1. or 2., wherein the insulating portion includes a resin portion including the protrusion and a heat-resistant portion located between the first conductive portion and the resin portion. 4. The battery module according to any one of 1. to 3., wherein the second conductive portion includes a voltage detection terminal electrically connected to the output terminal. 5. A battery cell having an output terminal; a housing that houses the battery cell; Equipped with the housing includes a first conductive portion and an insulating portion located at least partially between the battery cell and the first conductive portion; The insulating portion includes a concave-convex surface located between the first conductive portion and a second conductive portion including at least one of the output terminal and a conductive member electrically connected to the output terminal. 6. The battery module described in 5., wherein the insulating portion includes a resin portion including the uneven surface and a heat-resistant portion located between the first conductive portion and the resin portion. 7. The battery module described in 5. or 6., wherein the second conductive portion includes a voltage detection terminal electrically connected to the output terminal. Effect of the Invention

[0009] According to the above aspect of the present invention, electrical insulation between the battery cell and the container can be ensured. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is an exploded top perspective view of the battery module according to the embodiment. [Diagram 2] FIG. 4 is a front perspective view of a first plate according to the embodiment. [Diagram 3] FIG. 4 is a rear perspective view of a first plate according to the embodiment. [Figure 4] 2 is a cross-sectional view taken along the line AA in FIG. 1 in a state in which the battery module is assembled. [Diagram 5] FIG. 5 is a diagram showing a first modified example of FIG. [Figure 6] FIG. 5 is a diagram showing a second modified example of FIG. [Figure 7] FIG. 11 is a cross-sectional view of a portion of a battery module according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, similar components are given similar reference numerals and descriptions 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] In each figure, the X direction, the Y direction, and the Z direction are shown for the purpose of explanation. The X direction indicates the front-rear direction of the battery module 100. The Y direction is perpendicular to the X direction. The Y direction indicates the left-right direction of the battery module 100. The Z direction is perpendicular to both the X direction and the Y direction. The Z direction indicates the up-down direction of the battery module 100. The arrows indicating 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 the arrow indicating the X direction is referred to as the +X side, the opposite side of the tip of the arrow indicating the X direction is referred to as the -X side, the tip side of the arrow indicating the Y direction is referred to as the +Y side, the opposite side of the tip of the arrow indicating the Y direction is referred to as the -Y side, the tip side of the arrow indicating the Z direction is referred to as the +Z side, and the opposite side of the tip of the arrow indicating the Z direction is referred to as the -Z side. The relationship between the X direction, the Y direction, and the 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 container 200 .

[0015] The battery cells 110 and the compression pads 120 are alternately stacked in the Y direction. Each compression pad 120 is disposed between the battery cells 110 adjacent to each other in the Y direction and on both sides of the battery cells 110 in the Y direction. Hereinafter, the battery cells 110 and the compression pads 120 alternately stacked in the Y direction are referred to as a stack of battery cells 110 as necessary. 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) alternately stacked in the Y direction, and a separator (not shown) located between the positive electrodes and the negative electrodes adjacent 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 drawn 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 drawn 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. For example, in an embodiment, the output terminal of each battery cell 110 is the positive electrode tab 114 or the negative electrode tab 116. The potential of the battery element included in the battery cell 110 is output from the output terminal of each battery cell 110. However, the output terminal of each battery cell 110 is not limited to tabs such as the positive electrode tab 114 and the negative electrode tab 116.

[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. Hereinafter, unless otherwise specified, each battery cell 110 will be described as a battery cell containing an electrolyte.

[0018] The battery cells 110 are electrically connected in series and parallel. 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, and a tab group 118 including the positive electrode tab 114 and the negative electrode tab 116 is located. 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. The tab group 118 is also located on the -X side of the stack of battery cells 110. Thus, a plurality of cell groups are connected in series from the cell group located at one end side of the stack of battery cells 110 in the Y direction to the cell group located at the other end side 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 multiple battery cells 110 is not limited to the above example. For example, a stack of the battery cells 110 may be formed by connecting single battery cells 110 in series.

[0020] The first voltage detection device 130 detects the voltages of the multiple +X side tab group 118. The first voltage detection device 130 includes a first protector 131, multiple first voltage detection terminals 132, multiple 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 first voltage detection terminals 132 is located on the +X side of each of the +X side tab groups 118. Each of the first voltage detection terminals 132 is, for example, a conductive member such as metal. The -X side surface of each of the first voltage detection terminals 132 and the +X side surface of each of the +X side tab groups 118 are joined to each other by a joining method such as laser welding. Therefore, each of the first voltage detection terminals 132 and each of the +X side tab groups 118 are electrically connected to each other. Therefore, the first voltage detection device 130 can detect the voltage of each of the +X side tab groups 118 by each of the first voltage detection terminals 132. The first voltage detection terminals 132 are integrally held by the first protector 131. Therefore, by placing the first protector 131 at an appropriate position with respect to the stack of the battery cells 110, each of the first voltage detection terminals 132 can be placed at an appropriate position with respect to each of the +X side tab groups 118.

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

[0024] The first bus bar 135 is disposed at an end portion on the +Y side of the first protector 131. The first bus bar 135 is electrically connected to a positive electrode tab 114 drawn out to the +X side from a battery cell 110 of a cell group located at an 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 multiple -X side tab groups 118. The second voltage detection device 140 includes a second protector 141, multiple second voltage detection terminals 142, multiple 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 second voltage detection terminals 142 is located on the -X side of each of the -X side tab groups 118. Each of the second voltage detection terminals 142 is, for example, a conductive member such as metal. The +X side surface of each of the second voltage detection terminals 142 and the -X side surface of each of the -X side tab groups 118 are joined to each other by a joining method such as laser welding. Therefore, each of the second voltage detection terminals 142 and each of the -X side tab groups 118 are electrically connected to each other. Therefore, the second voltage detection device 140 can detect the voltage of each of the -X side tab groups 118 by each of the second voltage detection terminals 142. The second voltage detection terminals 142 are integrally held by the second protector 141. Therefore, by placing the second protector 141 at an appropriate position with respect to the stack of the battery cells 110, each of the second voltage detection terminals 142 can be placed at an appropriate position with respect to each of the -X side tab groups 118.

[0028] One end of each second voltage detection line 143 and each second voltage detection terminal 142 are electrically connected to each other. The other end of each second voltage detection line 143 and the second connector 144 are electrically connected to each other. 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 each second voltage detection line 143 and the other end of each second voltage detection line 143 via the second protector 141.

[0029] The second bus bar 145 is disposed at an end portion on the -Y side of the second protector 141. The second bus bar 145 is electrically connected to a negative electrode tab 116 drawn out to the -X side from a battery cell 110 of a cell group located at an 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] In the example shown in FIG. 1, the positive electrode tab 114 at the end of the multiple cell groups connected in series is drawn 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 the multiple cell groups connected in series is drawn 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 the multiple cell groups connected in series may differ depending on the number of battery cells 110 included in the stack of battery cells 110. For example, there are cases 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 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.

[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 the 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 the 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 the battery cells 110. The fourth plate 240 covers the -Y side portion of the stack of the battery cells 110. The fifth plate 250 covers the +Z side portion of the stack of the battery cells 110. The sixth plate 260 covers the -Z side portion of the stack of the 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 the battery cells 110. Thus, heat generated from the stack of the battery cells 110 can be released downwards of the battery module 100 through the thermally conductive adhesive 270.

[0033] Fig. 2 is a front perspective view of the first plate 210 according to the embodiment. Fig. 3 is a rear perspective view of the first plate 210 according to the embodiment. Fig. 4 is a cross-sectional view corresponding to the AA cross section in Fig. 1 in a state in which the battery module 100 is assembled.

[0034] The first plate 210 according to the embodiment will be described with reference to Figures 2 to 4, and also with reference to Figure 1 as necessary. The matters described below regarding the first plate 210 according to the embodiment can be similarly applied to the second plate 220 according to the embodiment.

[0035] As shown in FIG. 2 to FIG. 4, the first plate 210 includes a first metal part 212, a first resin part 214, and a first fireproof part 216. The first metal part 212 includes a first metal plate 212a, a first metal protrusion 212b, and a second metal protrusion 212c. The first metal plate 212a defines a first notch 212a1 and a second notch 212a2. The first resin part 214 includes a first resin plate 214a, a plurality of first resin protrusions 214b, and a plurality of second resin protrusions 214c. The first fireproof part 216 includes a first fireproof sheet 216a, a first fireproof extension sheet 216b1, and a second fireproof extension sheet 216b2.

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

[0037] The first metal plate 212a has a thickness that is approximately parallel to the X direction. Specifically, the first metal plate 212a has a substantially rectangular shape having 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, except for the first notch 212a1 and the second notch 212a2.

[0038] As shown in Fig. 2, the first notch 212a1 is located in a portion on the +Y side of the long side on the +Z side of the first metal plate 212a. 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 conductive member electrically connected to the battery cell 110. Therefore, electrical insulation between the first metal plate 212a and the first bus bar 135 can be ensured compared to a case in which the first metal plate 212a does not define the first notch 212a1.

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

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

[0041] The first metal protrusion 212b is located at an end portion on the -Z side of the -X side surface of the first metal plate 212a. The first metal protrusion 212b protrudes toward the -X side. The first metal protrusion 212b extends along the edge of the first metal plate 212a on the -Z side. The first metal plate 212a and the first metal protrusion 212b are integral with each other.

[0042] The second metal protrusion 212c is located at the end portion on the +Z side of the -X side surface of the first metal plate 212a. The second metal protrusion 212c protrudes toward the -X side. The second metal protrusion 212c extends along the edge on the +Z side of the first metal plate 212a, except for the first notch 212a1 and the second notch 212a2. The first metal plate 212a and the second metal protrusion 212c are integral with each other.

[0043] The first resin portion 214 is an insulating portion. The first resin portion 214 is made of a resin such as polypropylene (PP).

[0044] The first resin plate 214a has a thickness that is approximately parallel to the X direction. Specifically, the first resin plate 214a has an approximately rectangular shape having 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. As shown in Figs. 3 and 4, the -Z side long side of the first resin plate 214a and the +Z side surface of the first metal protrusion 212b are spaced apart from each other in the Z direction. Therefore, a portion of the first fireproof sheet 216a described later is exposed toward the -X side between the -Z side long side of the first resin plate 214a and the +Z side surface of the first metal protrusion 212b.

[0045] 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 part 212. Therefore, the first resin plate 214a is at least partially located in the X direction between the -X side surface of the first metal plate 212a and the +X side surfaces of the tab group 118, the first voltage detection terminal 132, and the first bus bar 135 on the +X side. Therefore, the first resin plate 214a can suppress short circuits between the first metal plate 212a and each of the tab group 118, the first voltage detection terminal 132, and the first bus bar 135 on the +X side.

[0046] The first resin protrusions 214b are provided on the surface side of the first resin plate 214a on the +X side. For example, the first resin plate 214a and the first resin protrusions 214b are integrally formed by resin molding. The first metal plate 212a and the first resin plate 214a are joined to each other by heat caulking the first resin protrusions 214b in a state in which a first fireproof sheet 216a described later is at least partially disposed between the -X side surface of the first metal plate 212a and the +X side surface of the first resin plate 214a. Specifically, in a state in which the first metal plate 212a and the first resin plate 214a are joined to each other, each of the first resin protrusions 214b penetrates a through hole provided in the first fireproof sheet 216a and a through hole provided in the first metal plate 212a in the X direction. The dimension of the end portion on the +X side 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 plate 212a in the direction perpendicular to the X direction by heat crimping the end portion on the +X side of each first resin protrusion 214b. Therefore, the first metal plate 212a and the first resin plate 214a are joined to each other in a state in which the first metal plate 212a does not come off the first resin plate 214a toward the +X side. However, the method of joining the first metal plate 212a and the first resin plate 214a is not limited to heat crimping the end portion on the +X side of each first resin part 214.

[0047] The second resin protrusions 214c are provided on the -X side surface of the first resin plate 214a. For example, the first resin plate 214a and the second resin protrusions 214c are integrally formed by resin molding. The -X side surface of each second resin protrusion 214c and the +X side surface of each first voltage detection terminal 132 face each other in the X direction in a state in which 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. Instead of the second resin protrusions 214c, a single second resin protrusion 214c extending in the Y direction may be provided. When a single second resin protrusion 214c is provided, the -X side surface of the second resin protrusion 214c and the +X side surface of each first voltage detection terminal 132 face each other in the X direction when 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.

[0048] The moldability of the first resin portion 214 is higher than the moldability of the first fire-resistant portion 216. Therefore, in the embodiment, the degree of freedom of the shape of the -X side of the first plate 210 can be improved compared to a case in which 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.

[0049] The first refractory portion 216 is an insulating portion. The first refractory portion 216 includes a refractory material such as silicon fiber.

[0050] The first fire-resistant sheet 216a has a thickness approximately parallel to the X-direction. Specifically, the first resin plate 214a, except for the first fire-resistant extending sheet 216b1 and the second fire-resistant extending sheet 216b2, has a substantially rectangular shape having a pair of long sides approximately parallel to the Y-direction and a pair of short sides approximately parallel to the Z-direction.

[0051] The first fireproof sheet 216a has electrical insulation. The first fireproof sheet 216a covers substantially the entire surface of the -X side of the first metal part 212 except for the first metal protrusion 212b and the second metal protrusion 212c. Therefore, the first fireproof sheet 216a is at least partially located in the X direction between the -X side surface of the first metal plate 212a and the +X side surfaces of the tab group 118, the first voltage detection terminal 132, and the first bus bar 135 on the +X side. Therefore, the first fireproof sheet 216a can suppress short circuits between the first metal plate 212a and each of the tab group 118, the first voltage detection terminal 132, and the first bus bar 135 on the +X side.

[0052] The first fireproof sheet 216a does not have to cover substantially the entire surface of the -X side of the first metal plate 212a. For example, the first fireproof sheet 216a may partially cover the portions of the -X side surface of the first metal plate 212a 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 fireproof sheet 216a partially covers the portions of the -X side surface of the first metal plate 212a, the first fireproof sheet 216a can suppress short circuits between the first metal plate 212a 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 plate 212a, 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 plate 212a.

[0053] The first fireproof sheet 216a is disposed between the +Z side surface of the first metal projection 212b and the -Z side surface of the second metal projection 212c. Therefore, it is possible to prevent the -Z side end of the first fireproof sheet 216a from entering the gap between the -Z side end of the first plate 210 and the +Z side surface of the +X side end of the sixth plate 260. Therefore, compared to the case where the -Z side end of the first fireproof sheet 216a enters the gap, the -Z side end of the first plate 210 and the +X side end of the sixth plate 260 can be more reliably joined by a joining method such as laser welding. Similarly, it is possible to prevent the +Z side end of the first fireproof sheet 216a from entering the gap between the +Z side end of the first plate 210 and the +Z side surface of the +X side end of the fifth plate 250. Therefore, compared to the case where the +Z side end of the first fire-resistant sheet 216a gets into the gap, the +Z side end of the first plate 210 and the +X side end of the fifth plate 250 can be more reliably joined by a joining method such as laser welding.

[0054] 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 plate 212a. 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 plate 212a facing the +Z side. Therefore, compared to a case where the first fire-resistant extension sheet 216b1 does not cover the edge of the first metal plate 212a, it is possible to ensure electrical insulation between the first metal plate 212a and the conductive member disposed around the first notch 212a1. For example, a connection bus bar (not shown) that electrically connects the first bus bar 135 and a bus bar of an external device such as another battery module may be disposed around the first notch 212a1. In the embodiment, even if the connection bus bar falls toward the edge of the first metal plate 212a, a short circuit between the connection bus bar and the first metal plate 212a can be suppressed by the first fire-resistant extension sheet 216b1.

[0055] 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 plate 212a. 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 plate 212a facing the +Z side. Therefore, compared to a case where the second fire-resistant extension sheet 216b2 does not cover the edge of the first metal plate 212a, it is possible to ensure electrical insulation between the first metal plate 212a and the conductive member disposed around the second notch 212a2. For example, a harness (not shown) electrically connected to the first connector 134 may be disposed around the second notch 212a2. In the embodiment, even if the harness falls toward the edge of the first metal plate 212a, a short circuit between the harness and the first metal plate 212a can be suppressed by the second fire-resistant extending sheet 216b2.

[0056] In the embodiment, the first fire-resistant portion 216 covers at least a part of the edge of the first metal plate 212a, such as the first notch 212a1 and the second notch 212a2. However, the first fire-resistant portion 216 may cover at least a part of an edge different from the edge of the notch of the first metal plate 212a. For example, the first fire-resistant portion 216 may cover at least a part of the edge of the first metal plate 212a in a state in which the first metal plate 212a does not define a notch. When the first fire-resistant portion 216 covers at least a part of the edge of the first metal plate 212a, electrical insulation between the first metal plate 212a and the conductive member disposed around the part of the edge of the first metal plate 212a covered by the first fire-resistant portion 216 can be ensured, compared to a case in which the first fire-resistant portion 216 does not cover any part of the edge of the first metal plate 212a.

[0057] The first fire-resistant portion 216 is a heat-resistant portion having a relatively high heat resistance. As the heat resistance of the first fire-resistant portion 216, the electrical insulation of the first fire-resistant portion 216 is maintained, for example, after the first fire-resistant portion 216 is exposed to 800° C. for 10 minutes, preferably after the first fire-resistant portion 216 is 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 fire-resistant portion 216 can make the first fire-resistant portion 216 difficult 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 difficult 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 tab group 118 on the +X side, the first voltage detection terminal 132, and the first bus bar 135.

[0058] 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. When 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.

[0059] The first fire-resistant portion 216 further has a relatively high fire resistance. The fire resistance is determined by the time required for a flame to burn a certain member. The longer the time required for the flame to burn a member, the higher the fire resistance, and the shorter the time required for the flame to burn a member, the lower the fire resistance. In the embodiment, even if abnormal heat is generated in the battery cell 110, the fire resistance of the first fire-resistant portion 216 can make the first fire-resistant portion 216 difficult 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 difficult 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 tab group 118 on the +X side, the first voltage detection terminal 132, and the first bus bar 135.

[0060] 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. When 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.

[0061] 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.

[0062] The first plate 210 may have a heat-resistant portion instead of the first fire-resistant portion 216. The heat-resistant portion may or may not have fire resistance. When the first plate 210 has a heat-resistant portion, even if abnormal heat generation occurs in the battery cell 110, the heat resistance of the heat-resistant portion can make the heat-resistant portion less likely to melt.

[0063] 4, a description will be given of electrical insulation between the first metal portion 212 and the first voltage detection terminal 132. In the example shown in Fig. 4, the first voltage detection terminal 132 is a conductive member electrically connected to the tab group 118 on the +X side.

[0064] In FIG. 4, for the purpose of explanation, the creeping path C between the +Z side surface of the first metal protrusion 212b and the +X side surface of the first voltage detection terminal 132 is illustrated by a thick line. The longer the total length of the creeping path C, the easier it is to ensure electrical insulation between the first voltage detection terminal 132 and the first metal part 212. The creeping path C shown in FIG. 4 runs along the -X side surface of the first fireproof sheet 216a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c, and runs along the -Z side surface of the second resin protrusion 214c between the -X side surface of the first fireproof sheet 216a and the +X side surface of the first voltage detection terminal 132. As shown in FIG. 4, a part of the creeping path C is formed in the space between the -X side end of the -Z side surface of the second resin protrusion 214c and the +X side surface of the first voltage detection terminal 132. The reason why the portion of the creeping path C is formed in the space is because the -X side surface of the second resin protrusion 214c is located closer to the +X side surface of the first voltage detection terminal 132 than the -X side surface of the first resin plate 214a and the -X side surface of the first fire-resistant sheet 216a. In other words, the position where discharge occurs in the space between the insulating portion including the first resin portion 214 and the first fire-resistant portion 216 and the conductive portion including the +X side tab group 118 and the first voltage detection terminal 132 can be adjusted according to the position of the second resin protrusion 214c in the Z direction.

[0065] The first voltage detection terminal 132 is movable in the X direction. In the example shown in Fig. 4, the +X side surface of the first voltage detection terminal 132 and the -X side surface of the second resin protrusion 214c face each other with a gap therebetween. However, when the first voltage detection terminal 132 moves toward the +X side, the +X side surface of the first voltage detection terminal 132 and the -X side surface of the second resin protrusion 214c may come into contact with each other.

[0066] In the example shown in FIG. 4, the second resin protrusion 214c protrudes toward the first voltage detection terminal 132. Therefore, in the example shown in FIG. 4, even if the first voltage detection terminal 132 moves toward the +X side, the movement of the first voltage detection terminal 132 toward the +X side can be restricted by the contact between the -X side surface of the second resin protrusion 214c and the +X side surface of the first voltage detection terminal 132. Therefore, in the example shown in FIG. 4, it is easier to ensure the distance between the -X side surface of the first fireproof sheet 216a and the +X side surface of the first voltage detection terminal 132 compared to the case where the second resin protrusion 214c is not provided. Therefore, in the example shown in FIG. 4, it is easier to ensure the electrical insulation between the first voltage detection terminal 132 and the first metal part 212 compared to the case where the second resin protrusion 214c is not provided.

[0067] 4, the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is shifted toward the center of the first voltage detection terminal 132 with respect to the end of the first voltage detection terminal 132 on the -Z side. That is, the distance in the Z direction between the -Z side surface of the second resin protrusion 214c and the +Z side surface of the sixth plate 260 is longer than the distance in the Z direction between the end of the -Z side of the first voltage detection terminal 132 and the +Z side surface of the sixth plate 260. Therefore, in the example shown in FIG. 4, compared to the case where the end of the -Z side of the second resin protrusion 214c and the end of the -Z side of the first voltage detection terminal 132 overlap in the X direction, a creeping path can be formed along the -Z side surface of the second resin protrusion 214c at a position farther away from the +Z side surface of the first metal protrusion 212b toward the +Z side. Therefore, in the example shown in FIG. 4, compared to the case where the -Z side end of the second resin protrusion 214c and the -Z side end of the first voltage detection terminal 132 overlap in the X direction, the creeping path along the -X side surface of the first fire-resistant sheet 216a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c can be made longer.

[0068] 4, the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is located relatively close to the -Z side end of the first voltage detection terminal 132. Specifically, the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is located between the -Z side end of the first voltage detection terminal 132 and the -Z side end of the +X side tab group 118. Therefore, compared to a case in which the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is located relatively far from the -Z side end of the first voltage detection terminal 132, the movement of the -Z side end of the first voltage detection terminal 132 toward the +X side can be more easily restricted by the first voltage detection terminal 132. Therefore, compared to a case where the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is located relatively far from the -Z side end of the first voltage detection terminal 132, it is easier to suppress discharge in the space between the -Z side end of the first voltage detection terminal 132 and the -X side surface of the first fire-resistant sheet 216a.

[0069] In the example shown in FIG. 4, the thickness of the first resin part 214 in the X direction is partially thickened by the second resin protrusion 214c. Therefore, it is possible to restrict the movement of the first voltage detection terminal 132 to the +X side without making the thickness of the first resin part 214 in the X direction thick over the entire first resin part 214. If the thickness of the first resin part 214 in the X direction is thick over the entire first resin part 214, the warping stress of the first resin part 214 becomes relatively large, and the influence of the warping stress of the first resin part 214 on the members surrounding the first resin part 214 becomes relatively large. In contrast, in the example shown in FIG. 4, the thickness of the first resin part 214 in the X direction can be made relatively thin except for the second resin protrusion 214c. Therefore, compared to the case where the thickness of the first resin part 214 in the X direction is thick over the entire first resin part 214, the influence of the warping stress of the first resin part 214 on the members surrounding the first resin part 214 can be made smaller.

[0070] In the example shown in Fig. 4, the second resin protrusion 214c suppresses short-circuiting between the conductive part including the first metal part 212 and the conductive part including the first voltage detection terminal 132 and the +X side tab group 118 via the creeping path C of the insulating part including the first resin plate 214a and the first fireproof sheet 216a. However, the structure to which the protrusion corresponding to the second resin protrusion 214c is applied is not limited to the example shown in Fig. 4. For example, the protrusion may protrude toward the +X side tab group 118 instead of the first voltage detection terminal 132.

[0071] In the embodiment, the output terminal of each battery cell 110 is a positive electrode tab 114 or a negative electrode tab 116. The output terminal of each battery cell 110 outputs the potential of the battery element included in the battery cell 110. However, the output terminal of each battery cell 110 is not limited to tabs such as the positive electrode tab 114 and the negative electrode tab 116.

[0072] FIG. 5 is a diagram showing a first modified example of FIG.

[0073] The creeping path C1 shown in FIG. 5 runs along the -X side surface of the first fire-resistant sheet 216a, the -Z side surface of the first resin plate 214a, and the -X side surface of the first resin plate 214a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c, and runs along the -Z side surface of the second resin protrusion 214c between the -X side surface of the first fire-resistant sheet 216a and the +X side surface of the first voltage detection terminal 132.

[0074] 5, the second resin protrusion 214c protrudes toward the first voltage detection terminal 132, similar to the example shown in FIG 4. Therefore, in the example shown in FIG 5, even if the first voltage detection terminal 132 moves toward the +X side, the movement of the first voltage detection terminal 132 toward the +X side can be restricted by contact between the -X side surface of the second resin protrusion 214c and the +X side surface of the first voltage detection terminal 132. Therefore, in the example shown in FIG 5, similar to the example shown in FIG 4, electrical insulation between the first voltage detection terminal 132 and the first metal portion 212 can be ensured compared to the case where the second resin protrusion 214c is not provided.

[0075] 5, similarly to the example shown in Fig. 4, the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is shifted toward the center of the first voltage detection terminal 132 with respect to the -Z side end of the first voltage detection terminal 132. Therefore, in the example shown in Fig. 5, similarly to the example shown in Fig. 4, the creeping path along the -X side surface of the first fireproof sheet 216a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c can be made longer than in the case where the -Z side end of the second resin protrusion 214c and the -Z side end of the first voltage detection terminal 132 overlap in the X direction.

[0076] 5, the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is relatively far from the end of the first voltage detection terminal 132 on the -Z side. Specifically, the second resin protrusion 214c and the +X side tab group 118 at least partially overlap each other in the X direction. Therefore, compared to a case in which the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is relatively close to the end of the first voltage detection terminal 132 on the -Z side, the creeping path along the -X side surface of the first fireproof sheet 216a, the -Z side surface of the first resin plate 214a, and the -X side surface of the first resin plate 214a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c can be made longer.

[0077] FIG. 6 is a diagram showing a second modified example of FIG.

[0078] The creeping path C2 shown in FIG. 6 runs along the -X side surface of the first fire-resistant sheet 216a between the +Z side surface of the first metal protrusion 212b and the -Z side surface of the second resin protrusion 214c, and runs along the -Z side surface of the second resin protrusion 214c between the -X side surface of the first fire-resistant sheet 216a and the +X side surface of the first voltage detection terminal 132.

[0079] 6, the second resin protrusion 214c protrudes toward the first voltage detection terminal 132, similar to the example shown in FIG 4. Therefore, in the example shown in FIG 6, even if the first voltage detection terminal 132 moves toward the +X side, the movement of the first voltage detection terminal 132 toward the +X side can be restricted by contact between the -X side surface of the second resin protrusion 214c and the +X side surface of the first voltage detection terminal 132. Therefore, in the example shown in FIG 6, similar to the example shown in FIG 4, electrical insulation between the first voltage detection terminal 132 and the first metal portion 212 can be ensured compared to the case where the second resin protrusion 214c is not provided.

[0080] 6, the -Z side end of the second resin protrusion 214c and the -Z side end of the first voltage detection terminal 132 overlap in the X direction. Therefore, compared to a case in which the second resin protrusion 214c protrudes toward a portion of the first voltage detection terminal 132 that is shifted toward the center of the first voltage detection terminal 132 with respect to the -Z side end of the first voltage detection terminal 132, it is possible to more easily restrict movement of the -Z side end of the first voltage detection terminal 132 toward the +X side.

[0081] Fig. 7 is a cross-sectional view of a portion of a battery module 100A according to a modified example. The cross section AA shown in Fig. 7 according to the modified example corresponds to the cross section AA in Fig. 4 according to the embodiment. The battery module 100A according to the modified example is similar to the battery module 100 according to the embodiment, except for the following points.

[0082] As shown in FIG. 7, the -X side surface of the -Z side end of the first resin plate 214aA of the first resin part 214A according to the modified example includes an uneven surface between the +Z side surface of the first metal protrusion 212b and the +X side surface of the first voltage detection terminal 132. In FIG. 7, the creeping path CA is illustrated by a thick line for the purpose of explanation. As shown by the creeping path CA, in the example shown in FIG. 7, the total length of the creeping path CA can be made longer than when the -X side surface of the -Z side end of the first resin plate 214aA is a flat surface perpendicular to the X direction. Therefore, compared to when the -X side surface of the -Z side end of the first resin plate 214aA is a flat surface perpendicular to the X direction, electrical insulation between the first voltage detection terminal 132 and the first metal part 212 can be ensured. The shape of the uneven surface is not particularly limited as long as the total length of the creeping path CA between the +Z side surface of the first metal protrusion 212b and the +X side surface of the first voltage detection terminal 132 can be made longer.

[0083] Although the embodiment and modified examples of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted. [Explanation of symbols]

[0084] 100,100A 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 container, 210 first plate, 212 first metal part, 212a first metal plate, 212a1 first notch, 212a2 second notch, 212b first metal protrusion, 212c Second metal projection, 214, 214A First resin portion, 214a, 214aA First resin plate, 214b First resin projection, 214c Second resin projection, 216 First fire-resistant portion, 216a First fire-resistant sheet, 216b2 Second fire-resistant extension sheet, 216b1 First fire-resistant extension sheet, 220 Second plate, 230 Third plate, 240 Fourth plate, 250 Fifth plate, 260 Sixth plate, 270 Thermally conductive adhesive, C, C1, C2, CA Surface path

Claims

1. A battery cell having an output terminal; a housing that houses the battery cell; Equipped with the housing includes a first conductive portion and an insulating portion located at least partially between the battery cell and the first conductive portion; the insulating portion includes a projection that projects toward a second conductive portion that includes at least one of the output terminal and a conductive member electrically connected to the output terminal.

2. The battery module according to claim 1 , wherein the projection protrudes toward a portion of the second conductive portion that is positioned offset toward a center of the second conductive portion with respect to an end of the second conductive portion.

3. The battery module according to claim 1 , wherein the insulating portion includes a resin portion including the protrusion, and a heat-resistant portion located between the first conductive portion and the resin portion.

4. The battery module according to claim 1 , wherein the second conductive portion includes a voltage detection terminal electrically connected to the output terminal.

5. A battery cell having an output terminal; a housing that houses the battery cell; Equipped with the housing includes a first conductive portion and an insulating portion located at least partially between the battery cell and the first conductive portion; The insulating portion includes an uneven surface located between the first conductive portion and a second conductive portion including at least one of the output terminal and a conductive member electrically connected to the output terminal.

6. The battery module according to claim 5 , wherein the insulating portion includes a resin portion including the uneven surface, and a heat-resistant portion located between the first conductive portion and the resin portion.

7. The battery module according to claim 5 , wherein the second conductive portion includes a voltage detection terminal electrically connected to the output terminal.

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