Battery Module

Abstract

To provide a battery module configured to reliably maintain mounting state of a cover body while preventing displacement of the cover body with respect to a plurality of battery cells.SOLUTION: A cover body 51 for covering a plurality of battery cells 11 includes: a plurality of sub cover sections 52 arranged in Y-axis direction with gaps 321; elastic deformation sections 311 which are provided between adjacent sub cover sections 52 and can be elastically deformed so that the size of the gap 321 may be changed; a first connection section 56 which is provided in a first sub cover section 52A arranged at one end in the Y-axis direction and connected to a mounted member so as to be fixed in the Y-axis direction; a second connection section 57 which is provided in a second sub cover section 52C arranged at the other end in the Y-axis direction and connected to the mounted member so as to be fixed in the Y-axis direction; and a third connection section 58 which is arranged between the first connection section 56 and the second connection section 57 and connected to the mounted member so as to be slid in the Y-axis direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] For example, Japanese Patent Application Laid-Open No. 2013-157128 (Patent Document 1) discloses a power supply device including a case body arranged on the electrode side of a battery assembly and having multiple terminal fixing parts connected via hinge parts, and a cover fixed to the case body and covering the multiple terminal fixing parts. The cover has two split cover parts and a hinge part connecting these split cover parts together.

[0003] Furthermore, JP 2014-229594 A (Patent Document 2) discloses a busbar module including a busbar case that houses a busbar, three insulating covers that cover the openings of the busbar case, and a flexible connecting member that connects adjacent insulating covers to each other.

[0004] In addition, JP 2018-181562 A (Patent Document 3) discloses a battery wiring module including a first split housing and a second split housing attached to the top of a secondary battery, a first cover and a second cover respectively covering the openings of the first split housing and the second split housing, and a tongue portion extending from the first cover toward the second cover. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-157128 A [Patent Document 2] JP 2014-229594 A [Patent Document 3] JP 2018-181562 A Summary of the Invention [Problem to be solved by the invention]

[0006] As disclosed in the above-mentioned Patent Document 1, a battery module is known that includes a plurality of battery cells (battery assembly) stacked in one direction and a cover body that is attached to a mounting member (case body) and arranged to cover the plurality of battery cells.

[0007] In such a battery module, when the temperature of the case body changes in accordance with the temperature change of the battery cells, the cover body expands or contracts according to its own linear expansion coefficient, which may cause the cover body to become misaligned with respect to the multiple battery cells or cause excessive stress to act on the connection part of the cover body to the mounting member, resulting in a loss of attachment of the cover body.

[0008] Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a battery module that can more reliably maintain the attachment state of the cover body while preventing the cover body from shifting in position relative to multiple battery cells. [Means for solving the problem]

[0009] [1] A battery module comprising: a plurality of stacked battery cells; a cover body arranged to cover the plurality of battery cells; and a mounting member to which the cover body is attached, wherein the cover body has: a plurality of split cover parts arranged with gaps in a first direction and separated from each other; an elastic deformation part extending between the split cover parts adjacent in the first direction and capable of elastically deforming so as to change the size of the gap; a first connection part provided on a first split cover part arranged at one end in the first direction among the plurality of split cover parts and connected to the mounting member so as to be fixed in the first direction; a second connection part provided on a second split cover part arranged at the other end in the first direction among the plurality of split cover parts and connected to the mounting member so as to be fixed in the first direction; and a third connection part provided on the split cover part, arranged between the first connection part and the second connection part in the first direction, and connected to the mounting member so as to be slidable in the first direction.

[0010] In the battery module configured in this manner, as the cover body expands and contracts due to temperature changes, the elastic deformation portion elastically deforms so that the size of the gap between adjacent split cover parts in the first direction changes. In this case, each connection part of the first connection part and the second connection part is connected to the attachment member so as to be fixed in the first direction, and the third connection part disposed between the first connection part and the second connection part is connected to the attachment member so as to be slidable in the first direction. Therefore, the sliding movement of the cover body along the first direction due to the expansion and contraction of the cover body is permitted while the positions of the first split cover part and the second split cover part are maintained at both ends in the first direction. This makes it possible to more reliably maintain the attachment state of the cover body while preventing the cover body from shifting in position relative to the multiple battery cells.

[0011] [2] The battery module described in [1], wherein the first split cover portion is further provided with the third connection portion, the second split cover portion is further provided with the third connection portion, and a third split cover portion among the multiple split cover portions, which is arranged between the first split cover portion and the second split cover portion in the first direction, is provided with a plurality of the third connection portions.

[0012] With a battery module configured in this manner, the positions of the first split cover part and the second split cover part can be maintained at both ends in the first direction, while allowing sliding movement of each of the first split cover part, the second split cover part and the third split cover part along the first direction.

[0013] [3] The battery module according to [1] or [2], wherein the elastic deformation portion extends while curving between the divided cover portions adjacent to each other in the first direction.

[0014] According to the battery module configured in this manner, it is possible to prevent excessive stress from being generated in the elastically deforming portion that elastically deforms in association with the expansion and contraction of the cover body.

[0015] [4] A battery module described in any of [1] to [3], wherein the plurality of battery cells are stacked in the first direction, the plurality of split cover portions face the plurality of battery cells in a second direction perpendicular to the first direction, and the elastic deformation portion is configured to protrude from the split cover portion in a third direction perpendicular to the first direction and the second direction.

[0016] According to the battery module configured in this manner, it is possible to prevent the size of the battery module from increasing in both the first and second directions due to the provision of the elastic deformation portion.

[0017] [5] The battery module according to any one of [1] to [4], wherein the cover body is integrally molded from a resin material.

[0018] According to the battery module configured in this manner, the cover body can be easily configured.

[0019] [6] A battery module described in any of [1] to [5], wherein the plurality of battery cells are stacked in the first direction, the plurality of divided cover parts face the plurality of battery cells in a second direction perpendicular to the first direction, and further includes a plurality of battery cell units arranged in the first direction, each of the battery cell units having a plurality of the battery cells arranged continuously in the first direction and a case body that houses the plurality of the battery cells arranged continuously in the first direction, and the gap extends along the boundary between the case bodies adjacent to each other in the first direction when viewed in the second direction.

[0020] According to a battery module configured in this manner, the gaps and the insulation distances between the battery cells can be set large.

[0021] [7] The battery module described in [6], further comprising: a bus bar connected to the battery cells for electrically connecting adjacent battery cells in the first direction; and a tab terminal connected to the bus bar and facing the cover body in the second direction, wherein the split cover part further has a protrusion that protrudes from an edge of the split cover part that forms the gap in a direction approaching the battery cells in the second direction and is provided along the tab terminal when viewed in the second direction.

[0022] According to the battery module configured in this manner, the gap and the insulation distance between the tab terminals can be set large. Effect of the Invention

[0023] As described above, according to the present invention, it is possible to provide a battery module that can prevent the cover body from shifting from its position relative to a plurality of battery cells and can more reliably maintain the attached state of the cover body. [Brief description of the drawings]

[0024] [Figure 1] 1 is a perspective view showing a battery module according to an embodiment of the present invention. [Diagram 2] FIG. 4 is another perspective view showing the battery module in the embodiment of the present invention. [Diagram 3] FIG. 2 is an exploded view showing the battery module in FIG. [Figure 4] FIG. 2 is a perspective view showing the internal structure of the battery module in FIG. [Diagram 5] 2 is another perspective view showing the internal structure of the battery module in FIG. 1. [Figure 6] 2 is a perspective view showing a battery cell unit that constitutes the battery module in FIG. 1. [Figure 7] 2 is a perspective view showing a battery cell that constitutes the battery cell unit in FIG. 1. [Figure 8] FIG. [Figure 9] FIG. 4 is another perspective view showing the cover body. [Figure 10] 9 is an enlarged perspective view showing the area surrounded by the two-dot chain line X in FIG. 8. [Figure 11] FIG. 2 is a top view partially showing the battery module in FIG. [Figure 12] 12 is a cross-sectional view showing the battery module as seen in the direction of the arrows on line XII-XII in FIG. 11. [Figure 13] 13 is a cross-sectional view showing the battery module as seen in the direction of the arrows on line XIII-XIII in FIG. 11. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0026] Figures 1 and 2 are perspective views showing a battery module in an embodiment of the present invention. Figure 3 is an exploded assembly diagram showing the battery module in Figure 1. Figures 4 and 5 are perspective views showing the internal structure of the battery module in Figure 1. Figure 6 is a perspective view showing a battery cell unit constituting the battery module in Figure 1. Figure 7 is a perspective view showing a battery cell constituting the battery cell unit in Figure 1.

[0027] 1 to 7, a battery module 100 is used as a power source for driving a vehicle such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a battery electric vehicle (BEV).

[0028] In this specification, for convenience of explaining the structure of the battery module 100, an axis extending parallel to the stacking direction of the multiple battery cells 11 described later is referred to as the "Y axis", an axis extending in a direction perpendicular to the Y axis based on the "Y axis" is referred to as the "X axis", and an axis extending in a direction perpendicular to the Y axis and the X axis is referred to as the "Z axis". The diagonally upper right direction on the paper surface of FIG. 1 is the "+Y axis direction", and the diagonally lower left direction is the "-Y axis direction". The diagonally lower right direction on the paper surface of FIG. 1 is the "+X axis direction", and the diagonally upper left direction is the "-X axis direction". The upward direction on the paper surface of FIG. 1 is the "+Z axis direction", and the downward direction is the "-Z axis direction". Typically, the battery module 100 is mounted on a vehicle in a position in which the +Z axis direction corresponds to the upward direction, and the -Z axis direction corresponds to the downward direction.

[0029] First, there will be described the overall structure of the battery module 100. As shown in Figures 4 and 5, the battery module 100 has a plurality of battery cell units 21 (21A, 21B, 21C, 21D, 21E, 21F).

[0030] The multiple battery cell units 21 are aligned in the Y-axis direction. Battery cell unit 21A, battery cell unit 21B, battery cell unit 21C, battery cell unit 21D, battery cell unit 21E, and battery cell unit 21F are aligned in the listed order from the negative side to the positive side in the Y-axis direction. Note that the number of battery cell units 21 included in the battery module 100 is not particularly limited as long as it is two or more.

[0031] As shown in FIGS. 6 and 7, each of the battery cell units 21A to 21F has a plurality of battery cells 11 and a case body 31.

[0032] In each battery cell unit 21, two battery cells 11 are arranged consecutively in the Y-axis direction. The number of battery cells 11 provided in each battery cell unit 21 is not particularly limited as long as it is a plurality of battery cells.

[0033] The battery cells 11 are lithium ion batteries. The battery cells 11 have a power density of 8000 W / L or more. The battery cells 11 are square and have a rectangular parallelepiped thin plate shape. The multiple battery cells 11 are stacked such that the Y-axis direction is the thickness direction of the battery cells 11.

[0034] The battery cell 11 has an exterior body 12. The exterior body 12 is made of a rectangular parallelepiped housing, and forms the external appearance of the battery cell 11. The exterior body 12 contains an electrode assembly and an electrolyte.

[0035] Exterior body 12 has cell side surface 13, cell side surface 14, and cell top surface 15. Each of cell side surface 13 and cell side surface 14 consists of a plane perpendicular to the Y-axis direction. Cell side surface 13 and cell side surface 14 face opposite each other in the Y-axis direction. Each of cell side surface 13 and cell side surface 14 has the largest area among the multiple side surfaces that exterior body 12 has. Cell top surface 15 consists of a plane perpendicular to the Z-axis direction. Cell top surface 15 faces the +Z-axis direction.

[0036] Battery cell 11 further has a gas exhaust valve 17. Gas exhaust valve 17 is provided on cell top surface 15. Gas exhaust valve 17 is provided in the center of cell top surface 15 in the X-axis direction. When gas generated inside exterior body 12 causes the internal pressure of exterior body 12 to reach or exceed a predetermined value, gas exhaust valve 17 exhausts the gas to the outside of exterior body 12. Gas from gas exhaust valve 17 flows through duct 71, which will be described later, and is exhausted to the outside of battery module 100.

[0037] The battery cell 11 further has electrode terminals 16, each of which is a pair of a positive terminal 16p and a negative terminal 16n. The electrode terminals 16 are provided on a cell top surface 15. The positive terminal 16p and the negative terminal 16n are provided on either side of the gas release valve 17 in the X-axis direction.

[0038] The case body 31 has a rectangular parallelepiped appearance. The case body 31 is made of resin. In each battery cell unit 21, the case body 31 houses a plurality of battery cells 11. The case body 31 has a case top 32. The case top 32 has a wall shape with the Z-axis direction being the thickness direction and disposed parallel to the X-axis-Y-axis plane.

[0039] As shown in Fig. 4 and Fig. 5, a plurality of battery cells 11 are stacked in the Y-axis direction across the battery cell units 21A to 21F arranged in the Y-axis direction. The plurality of battery cells 11 are stacked such that the cell side surfaces 13 face each other and the cell side surfaces 14 face each other between the battery cells 11 adjacent in the Y-axis direction. As a result, the positive electrode terminals 16p and the negative electrode terminals 16n are alternately arranged in the Y-axis direction in which the plurality of battery cells 11 are stacked. The positive electrode terminals 16p and the negative electrode terminals 16n adjacent in the Y-axis direction are connected to each other by a bus bar 26 (see Fig. 11 described later). As a result, the plurality of battery cells 11 are electrically connected to each other in series.

[0040] 1 to 5, the battery module 100 further includes a pair of end plates 42 (42P, 42Q) and a pair of bind bars 43. The pair of bind bars 43 and the pair of end plates 42 integrally hold multiple battery cell units 21 (multiple battery cells 11) aligned in the Y-axis direction.

[0041] The pair of end plates 42 are respectively arranged at both ends of the multiple battery cells 11 (multiple battery cell units 21) in the Y axis direction. The end plate 42P faces the battery cell unit 21A in the Y axis direction, and the end plate 42Q faces the battery cell unit 21F in the Y axis direction.

[0042] The end plate 42 has a plate portion 46 and an overhanging portion 47. The plate portion 46 has a plate shape with its thickness direction in the Y-axis direction. The overhanging portion 47 extends from the end (upper end) of the plate portion 46 in the +Z-axis direction in a direction away from the stack of battery cells 11 in the Y-axis direction. The overhanging portion 47 has a thickness in the Z-axis direction, and has an overhanging shape that extends in a strip shape along the upper end of the plate portion 46.

[0043] The pair of bind bars 43 are arranged on both ends of the stack of battery cells 11 in the X-axis direction. The bind bars 43 extend in the Y-axis direction. The end of the bind bar 43 in the -Y-axis direction is connected to the end plate 42P. The end of the bind bar 43 in the +Y-axis direction is connected to the end plate 42Q. The pair of bind bars 43, together with the pair of end plates 42, apply a restraining force in the Y-axis direction to the multiple battery cells 11 (multiple battery cell units 21).

[0044] The battery module 100 further has a positive terminal box 81 and a negative terminal box 86. The positive terminal box 81 and the negative terminal box 86 are made of resin. The positive terminal box 81 and the negative terminal box 86 respectively house a positive general terminal and a negative general terminal for connecting the battery module 100 to external wiring such as a cable disposed outside the battery module 100.

[0045] The positive terminal box 81 has a base 212 and an opening / closing door 211. The base 212 is attached to the end plate 42 (42P). The base 212 is provided so as to straddle the overhanging portion 47 in the Y-axis direction. A bus bar 27 extending from the battery cell 11 toward the positive general terminal is mounted on the base 212. The opening / closing door 211 is attached to the base 212 so as to be capable of being opened and closed. The negative terminal box 86 has a base 217 and an opening / closing door 216. The base 217 and the opening / closing door 216 correspond to the base 212 and the opening / closing door 211 in the positive terminal box 81, respectively. A bus bar 28 extending from the battery cell 11 toward the negative general terminal is mounted on the base 217.

[0046] The battery module 100 further has a duct 71 and a cover body 51. The duct 71 is made of resin. The duct 71 extends in the Y-axis direction while facing the multiple battery cells 11 (multiple battery cell units 21) in the Z-axis direction. The duct 71 forms a passage through which gas discharged from the multiple battery cells 11 flows. The duct 71 is attached to the multiple case bodies 31.

[0047] 3, the duct 71 has a duct main body 72 and a connector support 74. The duct main body 72 forms a main portion of the duct 71 for circulating gas from the battery cells 11. The duct main body 72 extends in the Y-axis direction while facing a plurality of gas exhaust valves 17 arranged at intervals in the Y-axis direction in the Z-axis direction. The connector support 74 extends in the +Y-axis direction from an end of the duct main body 72 in the +Y-axis direction. The connector support 74 has a plate shape that is arranged parallel to the X-axis-Y axis plane.

[0048] The cover body 51 is made of resin. The cover body 51 is provided so as to cover the multiple battery cells 11 in the Z-axis direction. The cover body 51 is provided so as to face the case top portion 32 of the case body 31 in the Z-axis direction. The cover body 51 is provided so as to further cover the bus bars 26, 27, 28 and the duct 71.

[0049] The cover body 51 is detachably attached to the multiple case bodies 31, the base 212, the base 217, and the duct 71. The multiple case bodies 31, the base 212, the base 217, and the duct 71 constitute an attachment member 30 to which the cover body 51 is attached.

[0050] 8 and 9 are perspective views showing the cover body. Next, the structure of the cover body 51 will be described in more detail.

[0051] 1 to 5, 8 and 9, the cover body 51 has a flat plate portion 231 and an edge portion 236. The flat plate portion 231 has a thickness in the Z-axis direction and is disposed parallel to an X-axis-Y-axis plane perpendicular to the Z-axis direction. The flat plate portion 231 has a rectangular shape as a whole when viewed from above. The flat plate portion 231 is provided facing the multiple battery cells 11 (multiple battery cell units 21) in the Z-axis direction. The edge portion 236 extends from the peripheral portion of the flat plate portion 231 in the -Z-axis direction. The edge portion 236 extends intermittently along the peripheral portion of the flat plate portion 231 while forming a height in the Z-axis direction.

[0052] The cover body 51 has a plurality of divided cover parts 52 and a plurality of elastic deformation parts 311. The divided cover parts 52 are separated from one another. The divided cover parts 52 are arranged side by side with gaps 321 provided in the Y-axis direction. The gaps 321 are slit-shaped, having a width in the Y-axis direction and extending in the X-axis direction.

[0053] The multiple divided cover parts 52 include a first divided cover part 52A, a second divided cover part 52C, and a third divided cover part 52B. The first divided cover part 52A is disposed at the end in the -Y axis direction of the multiple divided cover parts 52 aligned in the Y axis direction. The second divided cover part 52C is disposed at the end in the +Y axis direction of the multiple divided cover parts 52 aligned in the Y axis direction. The third divided cover part 52B is disposed between the first divided cover part 52A and the second divided cover part 52C in the Y axis direction.

[0054] The length of each of the first divided cover portion 52A and the second divided cover portion 52C in the Y axis direction is smaller than the length of the third divided cover portion 52B in the Y axis direction.

[0055] In the present embodiment, the gap 321 between the split cover parts 52 extends in a direction (X-axis direction) perpendicular to the stacking direction (Y-axis direction) of the battery cells 11, but the gap 321 may extend in any direction within the X-Y plane. The gap 321 may be composed of a combination of multiple sections extending in different directions (for example, a combination of a section extending in the X-axis direction, a section extending in the Y-axis direction, and a section extending in the X-axis direction). The cover body in the present invention may have two split cover parts, or may have four or more split cover parts.

[0056] Fig. 10 is an enlarged perspective view showing an area surrounded by a two-dot chain line X in Fig. 8. With reference to Fig. 8 to Fig. 10, the elastic deformation portion 311 extends between adjacent divided cover portions 52 in the Y-axis direction.

[0057] The multiple elastic deformation parts 311 include a first elastic deformation part 311A, a second elastic deformation part 311a, a third elastic deformation part 311B, and a fourth elastic deformation part 311b. The first elastic deformation part 311A ​​and the second elastic deformation part 311a extend between the first divided cover part 52A and the third divided cover part 52B. The first elastic deformation part 311A ​​and the second elastic deformation part 311a are provided symmetrically on both sides of the center line of the cover body 51 extending in the Y-axis direction. The third elastic deformation part 311B and the fourth elastic deformation part 311b extend between the third divided cover part 52B and the second divided cover part 52C. The third elastic deformation part 311B and the fourth elastic deformation part 311b are provided symmetrically on both sides of the center line of the cover body 51 extending in the Y-axis direction.

[0058] The elastic deformation portion 311 is configured to be elastically deformable so that the size of the gap 321 changes. The elastic deformation portion 311 is configured to be elastically deformable so that the length of the gap 321 in the Y-axis direction changes. The elastic deformation portion 311 is made of a resin material and is integrally provided to the multiple divided cover portions 52. The cover body 51 is integrally molded from a resin material. With this configuration, the cover body 51 is made of a single part, and therefore the manufacturing cost of the battery module 100 can be reduced.

[0059] Focusing on the first elastic deformation portion 311A ​​shown in Fig. 10, the first elastic deformation portion 311A ​​extends while curving between the first divided cover portion 52A and the third divided cover portion 52B. The first elastic deformation portion 311A ​​has a constant length in the Z-axis direction (the same length as the edge portion 236). The first elastic deformation portion 311A ​​is provided so as to protrude in the +X-axis direction from the divided cover portion 52 (first divided cover portion 52A, third divided cover portion 52B). The first elastic deformation portion 311A ​​is provided at a position overlapping the bind bar 43 when viewed in the Z-axis direction.

[0060] The first elastic deformation portion 311A ​​has a first base end portion 313, a second base end portion 314, and an intermediate portion 312. The first base end portion 313 is connected to the edge portion 236 of the first divided cover portion 52A. The second base end portion 314 is connected to the edge portion 236 of the third divided cover portion 52B. The intermediate portion 312 extends in an elliptical shape between the first base end portion 313 and the second base end portion 314. The intermediate portion 312 is provided so as to protrude from the first base end portion 313 and the second base end portion 314 in the +X-axis direction and the ±Y-axis direction. When the first elastic deformation portion 311A ​​is viewed in the Z-axis direction, the widths of the first base end portion 313 and the second base end portion 314 are larger than the width of the intermediate portion 312.

[0061] As the cover body 51 expands and contracts, the first elastic deformation portion 311A ​​elastically deforms so that the curvature of the intermediate portion 312 changes. In the present embodiment, since the first elastic deformation portion 311A ​​has a curved shape, it is possible to suppress the occurrence of excessive stress locally in the elastically deforming first elastic deformation portion 311A. Furthermore, since the first elastic deformation portion 311A ​​is provided so as to protrude in the +X-axis direction from the divided cover portion 52, the length (total height) of the battery module 100 in the Z-axis direction does not increase due to the installation of the first elastic deformation portion 311A.

[0062] Although the configuration of the first elastic deformation portion 311A ​​has been described here as a representative example, the second elastic deformation portion 311a, the third elastic deformation portion 311B, and the fourth elastic deformation portion 311b each have a configuration similar to that of the first elastic deformation portion 311A. The shape of the elastic deformation portion 311 is not particularly limited, and may be, for example, a U-shaped or triangular shape when viewed in the Z-axis direction.

[0063] Next, a description will be given of the attachment structure of cover body 51 to attachment target member 30. With reference to Figures 1 and 2, 8 and 9, cover body 51 further has a first connection portion 56, a second connection portion 57, and a third connection portion 58.

[0064] The first connection part 56 is provided on the first split cover part 52A. The first connection part 56 is connected to the attached member 30 so as to be fixed in the Y-axis direction. The second connection part 57 is provided on the second split cover part 52C. The second connection part 57 is connected to the attached member 30 so as to be fixed in the Y-axis direction. The third connection part 58 is provided on the split cover part 52 (the first split cover part 52A, the second split cover part 52C, the third split cover part 52B). The third connection part 58 is disposed between the first connection part 56 and the second connection part 57 in the Y-axis direction. The third connection part 58 is connected to the attached member 30 so as to be slidable in the Y-axis direction.

[0065] 4 and 5, the case bodies 31 constituting battery cell unit 21A, battery cell unit 21B, battery cell unit 21C, battery cell unit 21D, battery cell unit 21E and battery cell unit 21F are respectively shown as case body 31A, case body 31B, case body 31C, case body 31D, case body 31E and case body 31F. With reference to FIGS. 1 to 6, case body 31 further has a rib portion 113 and a claw portion 221.

[0066] The rib portion 113 protrudes from the case top 32, and extends in a rib shape so as to surround the electrode terminal 16 while increasing in height in the Z-axis direction. The claw portion 221 has a convex shape protruding in the X-axis direction from the side surface of the rib portion 113. The claw portion 221 is provided on each side surface of the rib portion 113 facing the +X-axis direction and the outer side surface of the rib portion 113 facing the -X-axis direction. The claw portion 221 has a convex shape protruding in the +X-axis direction on the outer side surface of the rib portion 113 facing the +X-axis direction, and has a convex shape protruding in the -X-axis direction on the outer side surface of the rib portion 113 facing the -X-axis direction. When the multiple case bodies 31 are arranged in the Y-axis direction, the multiple claw portions 221 are provided at intervals from each other in the Y-axis direction.

[0067] 1 to 5, the base 212 is provided with a claw portion 222 and a claw portion 225. The claw portion 222 is provided on the outer surface of the base 212 facing the +X-axis direction, and has a convex shape protruding in the +X-axis direction. The claw portion 225 is provided on the outer surface of the base 212 facing the -X-axis direction, and has a convex shape protruding in the -X-axis direction. The claw portion 222 and the claw portion 225 are provided directly above the end plate 42P. The base 217 is provided with a claw portion 223. The claw portion 223 is provided on the outer surface of the base 217 facing the +X-axis direction, and has a convex shape protruding in the +X-axis direction. The claw portion 223 is provided directly above the end plate 42Q.

[0068] The connector support portion 74 of the duct 71 is provided with a claw portion 224. The claw portion 224 is provided on the outer surface of the connector support portion 74 facing the -X-axis direction, and has a convex shape that protrudes in the -X-axis direction. The claw portion 224 is provided directly above the end plate 42Q.

[0069] 1 to 5 and 8 to 9, cover body 51 is provided with a plurality of openings 251, 252, 253, 254, and 255. The plurality of openings 251, 252, 253, 254, and 255 are provided in edge portion 236.

[0070] As shown in FIG. 1 and FIG. 2, the first divided cover part 52A has an opening 252 and an opening 255. The opening 252 and the opening 255 are provided in a portion of the first divided cover part 52A that covers the base 212. The claw part 222 and the claw part 225 are fitted into the opening 252 and the opening 255, respectively. The opening length (width) of the opening 252 in the Y-axis direction is approximately the same as the length (width) of the claw part 222 in the Y-axis direction, and the opening length (width) of the opening 255 in the Y-axis direction is approximately the same as the length (width) of the claw part 225 in the Y-axis direction. The claw part 222 and the claw part 225 are engaged in the Z-axis direction and the Y-axis direction on the inside of the opening 252 and the opening 255, respectively. With this configuration, the opening 252 and the opening 255 constitute the first connection part 56 that is connected to the mounting member 30 (base 212) so as to be fixed in the Y-axis direction.

[0071] The second split cover part 52C has an opening 253 and an opening 254. The opening 253 is provided in a portion of the second split cover part 52C that covers the base 217. The opening 254 is provided in a portion of the second split cover part 52C that covers the connector support part 74. The claw part 223 and the claw part 224 are fitted into the opening 253 and the opening 254, respectively. The opening length (width) of the opening 253 in the Y-axis direction is approximately the same as the length (width) of the claw part 223 in the Y-axis direction, and the opening length (width) of the opening 254 in the Y-axis direction is approximately the same as the length (width) of the claw part 224 in the Y-axis direction. The claw part 223 and the claw part 224 are engaged in the Z-axis direction and the Y-axis direction on the inside of the opening 253 and the opening 254, respectively. With this configuration, the opening 253 and the opening 254 form the second connection portion 57 that is connected to the attachment member 30 (the base 217, the connector support portion 74) so ​​as to be fixed in the Y-axis direction.

[0072] The first divided cover part 52A is further provided with a plurality of openings 251. The first divided cover part 52A has a plurality of openings 251 disposed between the openings 252 and 255 and the third divided cover part 52B in the Y-axis direction. The second divided cover part 52C has a plurality of openings 251 disposed between the openings 253 and 254 and the third divided cover part 52B in the Y-axis direction. The third divided cover part 52B has a plurality of openings 251 disposed between the openings 252 and 255 (first connecting part 56) and the openings 253 and 254 (second connecting part 57) in the Y-axis direction.

[0073] A plurality of claw portions 221 are fitted into the plurality of openings 251, respectively. The opening length (width) of the opening 251 in the Y-axis direction is greater than the length (width) of the claw portion 221 in the Y-axis direction. The claw portion 221 is disposed at a position away from the opening edge of the opening 251 in the ±Y-axis directions. The claw portion 221 is engaged only in the Z-axis direction inside the opening 251. With this configuration, the plurality of openings 251 form a third connection portion 58 that is connected to the attachment member 30 (plurality of case bodies 31) so as to be slidable in the Y-axis direction.

[0074] 1 and 2, in battery module 100 in the present embodiment, as cover body 51 expands due to a temperature change, elastic deformation portion 311 elastically deforms so that gap 321 between first divided cover portion 52A and third divided cover portion 52B and gap 321 between third divided cover portion 52B and second divided cover portion 52C decrease in size, and similarly, as cover body 51 contracts, elastic deformation portion 311 elastically deforms so that gap 321 increases. In this case, each connection portion of first connection portion 56 and second connection portion 57 is connected to attachment member 30 (base 212, base 217, connector support portion 74) so ​​as to be fixed in the Y-axis direction, while third connection portion 58 disposed between first connection portion 56 and second connection portion 57 is connected to attachment member 30 (plurality of case bodies 31) so as to be slidable in the Y-axis direction. With this configuration, the positions of the first divided cover part 52A and the second divided cover part 52C are maintained at both ends in the Y-axis direction, and the sliding movement of the cover body 51 along the Y-axis direction due to expansion and contraction of the cover body 51 is permitted. This makes it possible to prevent the cover body 51 from shifting in position relative to the multiple battery cells 11, while also preventing deformation of the cover body 51 or damage to the attachment state of the cover body 51 to the attachment member 30.

[0075] Fig. 11 is a top view partially showing the battery module in Fig. 1. Fig. 12 is a cross-sectional view showing the battery module seen in the direction of the arrows on the line XII-XII in Fig. 11. Fig. 13 is a cross-sectional view showing the battery module seen in the direction of the arrows on the line XIII-XIII in Fig. 11.

[0076] 11 to 13, gap 321 between first divided cover part 52A and third divided cover part 52B extends along the boundary between case body 31A and case body 31B adjacent to each other in the Y-axis direction when viewed in the Z-axis direction. Gap 321 protrudes from case top 32 in the +Z-axis direction and is located directly above rib portion 113 of case body 31 extending in the X-axis direction.

[0077] With this configuration, the insulation distance between the gap 321 and the battery cell 11 disposed adjacent to the gap 321 can be set large.

[0078] The battery module 100 further has a tab terminal 65. The tab terminal 65 is connected to the bus bar 26. The tab terminal 65 faces the cover body 51 in the Z-axis direction. The tab terminal 65 is provided as a terminal for detecting the voltage of each battery cell 11. The tab terminal 65 is connected to the positive electrode terminal 16p of each battery cell 11. The tab terminal 65 is provided at a position shifted in the X-axis direction between battery cells 11 adjacent to each other in the Y-axis direction. The tab terminal 65 is disposed between the bus bar 26 and the cover body 51 in the Z-axis direction.

[0079] The split cover part 52 has protrusions 331 (331A, 331B). The protrusions 331 protrude from the edge of the split cover part 52 that forms the gap 321 in the Z axis direction toward the battery cell 11 (-Z axis direction). The protrusions 331 are provided along the tab terminals 65 when viewed in the Z axis direction.

[0080] The protrusion 331A is provided on the first divided cover part 52A. When viewed in the Z-axis direction, the protrusion 331A is provided in an area on the negative side in the X-axis direction from the center line of the cover body 51 extending in the Y-axis direction. The protrusion 331A is First divided cover portion 52A to third divided cover portion 52B 2 and extends in the X-axis direction while having a constant width in the Y-axis direction. When viewed in the Z-axis direction, the protrusion 331A is provided along a tab terminal 65 connected to a bus bar 26 that connects the battery cells 11 together inside the battery cell unit 21A. When viewed in the Z-axis direction, the protrusion 331A extends in the X-axis direction at a position adjacent to the tab terminal 65 in the Y-axis direction.

[0081] The protrusion 331B is provided on the third divided cover part 52B. When viewed in the Z-axis direction, the protrusion 331B is provided in an area on the positive side in the X-axis direction from the center line of the cover body 51 extending in the Y-axis direction. The protrusion 331B is From the third divided cover portion 52B to the first divided cover portion 52A2 and extends in the X-axis direction while having a constant width in the Y-axis direction. When viewed in the Z-axis direction, the protrusion 331B is provided along the tab terminal 65 connected to the bus bar 26 that connects the battery cells 11 between the battery cell unit 21A and the battery cell unit 21B. When viewed in the Z-axis direction, the protrusion 331B extends in the X-axis direction at a position adjacent to the tab terminal 65 in the Y-axis direction.

[0082] Although not shown, the boundary portion between the third divided cover portion 52B and the second divided cover portion 52C has a similar configuration to the boundary portion between the first divided cover portion 52A and the third divided cover portion 52B described above.

[0083] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0084] 11 battery cell, 12 exterior body, 13, 14 cell side, 15 cell top surface, 16 electrode terminal, 16n negative electrode terminal, 16p positive electrode terminal, 17 gas exhaust valve, 21, 21A, 21B, 21C, 21D, 21E, 21F battery cell unit, 26, 27, 28 bus bar, 30 mounting member, 31, 31A, 31B, 31C, 31D, 31E, 31F case body, 32 case top, 42, 42P, 42Q end plate, 43 bind bar, 46 plate portion, 47 eaves portion, 51 cover body, 52 split cover portion, 52A first split cover portion, 52B third split cover portion, 52C second split cover portion, 56 first connection portion, 57 second connection portion, 58 third connection portion, 65 tab terminal, 71 Duct, 72 duct main body, 74 connector support portion, 81 positive terminal box, 86 negative terminal box, 100 battery module, 113 rib portion, 211, 216 opening and closing door, 212, 217 base, 221, 222, 223, 224, 225 claw portion, 231 flat plate portion, 236 edge portion, 251, 252, 253, 254, 255 opening portion, 311 elastic deformation portion, 311A ​​first elastic deformation portion, 311B third elastic deformation portion, 311a second elastic deformation portion, 311b fourth elastic deformation portion, 312 middle portion, 313 first base end portion, 314 second base end portion, 321 gap, 331, 331A, 331B protruding portion.

Claims

1. A plurality of stacked battery cells; A cover body provided to cover the plurality of battery cells; a mounting member to which the cover body is attached, The cover body is A plurality of split cover portions arranged with gaps in a first direction and separated from each other; an elastic deformation portion having a first base end portion and a second base end portion respectively connected to the divided cover portions adjacent to each other in the first direction, extending from the first base end portion to the second base end portion, and capable of elastic deformation such that a size of the gap changes; a first connection portion provided on a first split cover portion disposed at one end in the first direction among the plurality of split cover portions, the first connection portion being connected to the mounting member so as to be fixed in the first direction; a second connection portion provided on a second split cover portion disposed at the other end in the first direction among the plurality of split cover portions, the second connection portion being connected to the attachment member so as to be fixed in the first direction; a third connection portion provided on the divided cover portion, disposed between the first connection portion and the second connection portion in the first direction, and connected to the mounting member so as to be slidable in the first direction; The first divided cover portion is further provided with the third connection portion, The second divided cover portion is further provided with the third connection portion, A battery module, wherein a third split cover portion among the plurality of split cover portions is arranged between the first split cover portion and the second split cover portion in the first direction, and is provided with a plurality of the third connection portions.

2. The battery module according to claim 1 , wherein the elastic deformation portion extends while curving from the first base end portion to the second base end portion.

3. The plurality of battery cells are stacked in the first direction, the divided cover portions face the battery cells in a second direction perpendicular to the first direction; The battery module according to claim 1 , wherein the elastic deformation portion is provided so as to protrude from the divided cover portion in a third direction perpendicular to the first direction and the second direction.

4. The battery module according to claim 1 , wherein the cover body is integrally formed from a resin material.

5. The plurality of battery cells are stacked in the first direction, The divided cover portions face the battery cells in a second direction perpendicular to the first direction, and a plurality of battery cell units arranged in the first direction; Each of the battery cell units includes: A plurality of the battery cells arranged continuously in the first direction; a case body that houses the plurality of battery cells that are continuously aligned in the first direction, The battery module according to claim 1 , wherein the gap extends along a boundary between the case bodies adjacent to each other in the first direction when viewed in the second direction.

6. A plurality of stacked battery cells; A cover body provided to cover the plurality of battery cells; a mounting member to which the cover body is attached, The cover body is A plurality of split cover portions arranged with gaps in a first direction and separated from each other; an elastic deformation portion having a first base end portion and a second base end portion respectively connected to the divided cover portions adjacent to each other in the first direction, extending from the first base end portion to the second base end portion, and capable of elastic deformation such that a size of the gap changes; a first connection portion provided on a first split cover portion disposed at one end in the first direction among the plurality of split cover portions, the first connection portion being connected to the mounting member so as to be fixed in the first direction; a second connection portion provided on a second split cover portion disposed at the other end in the first direction among the plurality of split cover portions, the second connection portion being connected to the attachment member so as to be fixed in the first direction; a third connection portion provided on the divided cover portion, disposed between the first connection portion and the second connection portion in the first direction, and connected to the mounting member so as to be slidable in the first direction; The plurality of battery cells are stacked in the first direction, The divided cover portions face the battery cells in a second direction perpendicular to the first direction, and a plurality of battery cell units arranged in the first direction; Each of the battery cell units includes: A plurality of the battery cells arranged continuously in the first direction; a case body that houses the plurality of battery cells that are continuously aligned in the first direction, When viewed in the second direction, the gap extends along a boundary between the case bodies adjacent to each other in the first direction, and a bus bar connected to the battery cell and configured to electrically connect the battery cells adjacent to each other in the first direction; a tab terminal connected to the bus bar and facing the cover body in the second direction, the split cover portion protrudes from an edge of the split cover portion that forms the gap in the second direction toward the battery cell, and further has a protrusion that is arranged along the tab terminal when viewed in the second direction.

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