Battery pack

Abstract

To improve the workability of installing a heat insulating material.SOLUTION: A battery pack 10 includes a battery module 100, a heat insulating sheet 400, and a protrusion 340 that at least partially locks the heat insulating sheet 400 with the heat insulating sheet 400 covering the battery module 100 at least partially.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In recent years, various battery packs have been developed, each of which includes at least one battery module.

[0003] Patent Document 1 describes a battery module that includes an electrical separator provided with holes for welding aluminum bars, and a cover that is integrally formed with the electrical separator and can be folded over the electrical separator.

[0004] Patent Document 2 describes a battery assembly. The battery assembly includes a battery pack and side plates with hooks attached to both sides of the battery pack. An aerogel felt is provided on the outside of the battery assembly. A hanging ring is provided on the top of the aerogel felt to connect to the hooks on the side plates. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] China Utility Model Registration No. 213660570 [Patent Document 2] China Utility Model Registration No. 208460835 Summary of the Invention [Problem to be solved by the invention]

[0006] When an abnormality occurs in a battery module, relatively high-temperature gas or flames may be generated from the battery module. Furthermore, high-voltage components may be installed in the battery pack. To protect components around the battery module from the gas, flame, and high-voltage components, a heat insulating material such as a heat insulating sheet may be installed. In the manufacture of battery packs, it may be necessary to improve the workability of installing the heat insulating material.

[0007] One object of the present invention is to improve the workability of installing thermal insulation material. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0008] One aspect of the present invention is as follows. 1. A battery module; Heat insulating material; a structure that at least partially holds the heat insulating material in a state where the heat insulating material at least partially covers the battery module; A battery pack comprising: 2. The battery pack according to claim 1, wherein the structure penetrates the heat insulating material. 3. The thermal insulation defines a slit through which the structure passes; 3. The battery pack according to 2., wherein the slit is at least partially branched. 4. The battery pack according to any one of 1. to 3., further comprising wiring attached to the structure. 5. Further comprising a housing for accommodating the battery module; 5. The battery pack according to any one of 1. to 4., wherein the heat insulating material is at least partially located between the battery module and the housing. 6. The battery pack according to any one of 1. to 5., wherein the structure is provided on a member that at least partially overlaps the battery pack. [Effects of the Invention]

[0009] According to the above aspect of the present invention, the workability of installing the heat insulating material can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 2 is a schematic plan view of the battery pack according to the embodiment with the upper plate removed. [Figure 2] FIG. 2 is a perspective view of a battery module and its periphery according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 4] FIG. 1 is a top view of a protrusion according to an embodiment. [Figure 5] FIG. 10 is a top view of a slit in the fixed sheet portion according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

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

[0012] Fig. 1 is a schematic plan view of a battery pack 10 according to an embodiment with an upper plate 230 removed. Fig. 2 is a perspective view of a battery module 100 according to an embodiment and its periphery. Fig. 3 is a cross-sectional view taken along line AA in Fig. 2.

[0013] In the embodiment, the battery pack 10 is mounted on an automobile. Specifically, the battery pack 10 is mounted between the front and rear wheels of the automobile. Unless otherwise specified, the following description will be given assuming that the battery pack 10 is mounted on an automobile. However, the battery pack 10 can also be used for purposes other than automobiles.

[0014] For the purpose of explanation, the X, Y, and Z directions are shown in each figure. The X direction indicates the front-to-rear direction of the battery pack 10. The Y direction is perpendicular to the X direction. The Y direction indicates the left-to-right direction of the battery pack 10. The Z direction is perpendicular to both the X and Y directions. The Z direction indicates the up-to-down direction of the battery pack 10. The arrows pointing to the X direction, the Y direction, and the Z direction indicate the front, left, and up directions of the battery pack 10, respectively. In FIG. 1, a white circle with a black dot indicating the Z direction indicates that the arrow pointing to the Z direction extends from the back of the page to the front. In FIG. 3, a white circle with a black dot indicating the X direction indicates that the arrow pointing to the X direction extends from the back of the page to the front. However, the relationship between the X direction, Y direction, and Z direction and the front-to-rear direction, left-to-right direction, and up-to-down direction of the battery pack 10 is not limited to this example.

[0015] In the embodiment, the front-rear direction, left-right direction, and up-down direction of the battery pack 10 are determined by the vehicle in which the battery pack 10 is mounted. The X direction, Y direction, and Z direction respectively indicate the front-rear direction, left-right direction, and up-down direction of the vehicle. The arrow pointing to the X direction, the arrow pointing to the Y direction, and the arrow pointing to the Z direction respectively indicate the front, left, and up directions of the vehicle. However, the relationship between the front-rear direction, left-right direction, and up-down direction of the battery pack 10 and the front-rear direction, left-right, and up-down directions of the vehicle is not limited to this example.

[0016] Hereinafter, as needed, the side indicated by the arrow indicating the X direction will be referred to as the +X side, and the side opposite the side indicated by the arrow indicating the X direction will be referred to as the -X side. Hereinafter, as needed, the side indicated by the arrow indicating the Y direction will be referred to as the +Y side, and the side opposite the side indicated by the arrow indicating the Y direction will be referred to as the -Y side. Hereinafter, as needed, the side indicated by the arrow indicating the Z direction will be referred to as the +Z side, and the side opposite the side indicated by the arrow indicating the Z direction will be referred to as the -Z side.

[0017] A battery pack 10 according to an embodiment will be described with reference to FIG. 1, and if necessary, with reference to FIG. 2 and FIG.

[0018] As shown in FIG. 1, the battery pack 10 includes a plurality of battery modules 100 and a housing 200.

[0019] In the example shown in Fig. 1, four battery modules 100 are arranged in two rows and two columns in the X and Y directions. The number and arrangement of the battery modules 100 are not limited to those shown in Fig. 1. For example, the battery pack 10 may include only one battery module 100. Alternatively, the battery pack 10 may include, for example, five or more battery modules 100.

[0020] Each battery module 100 has a plurality of battery cells (not shown) stacked in a direction perpendicular to the Z direction. The plurality of battery cells are electrically connected to one another in series, parallel, or a combination of series and parallel. Each battery module 100 shown in FIG. 1 shows the shape of a housing that houses the battery cells (not shown). In the example shown in FIG. 1, the housing has a substantially rectangular parallelepiped shape with a substantially rectangular bottom surface having a pair of long sides extending in the X direction and another pair of sides extending in the Y direction when viewed from the Z direction.

[0021] 1 to 3, the housing 200 has a lower plate 210, side frames 220, an upper plate 230, and a support frame 240. The lower plate 210 and the side frames 220 are sometimes collectively referred to as a lower case. The upper plate 230 is sometimes referred to as an upper case. The housing 200 houses a plurality of battery modules 100.

[0022] The lower plate 210 is disposed substantially perpendicular to the Z direction. The multiple battery modules 100 are located on the +Z side of the +Z side surface of the lower plate 210. As shown in Fig. 1, the lower plate 210 has a substantially rectangular shape with a pair of long sides substantially parallel to the X direction and a pair of short sides substantially parallel to the Y direction. The shape of the lower plate 210 is not limited to the example shown in Fig. 1.

[0023] The side frame 220 extends toward the +Z side from the entire periphery in the Z direction of the +Z side surface of the lower plate 210. When viewed from the Z direction, the side frame 220 surrounds the area where the multiple battery modules 100 are located.

[0024] The upper plate 230 is located on the +Z side with respect to the multiple battery modules 100 and the side frame 220. When viewed from the Z direction, the lower plate 210 and the upper plate 230 have substantially the same shape. In FIGS. 2 and 3, the portion of the upper plate 230 located around the battery modules 100 is selectively illustrated. The side frame 220 and the portion of the upper plate 230 that overlaps with the side frame 220 in the Z direction are fastened to each other with fasteners such as bolts (not shown). With the side frame 220 and the portion of the upper plate 230 that overlaps with the side frame 220 in the Z direction fastened to each other, the lower plate 210, the side frame 220, and the upper plate 230 form an accommodation space that accommodates multiple battery modules 100.

[0025] 1, when viewed in the Z direction, the support frame 240 extends in a frame shape that at least partially surrounds each battery module 100. Both Y-direction side portions of each battery module 100 and both Y-direction side portions of the support frame 240 of each battery module 100 are fastened to each other by fasteners such as bolts (not shown). With these portions of each battery module 100 and these portions of the support frame 240 fastened to each other, each battery module 100 and the housing 200 are attached to each other.

[0026] The battery module 100 and its surroundings will be described with reference to Figures 2 and 3. The description of the battery module 100 shown in Figures 2 and 3 can be applied to any of the multiple battery modules 100 mounted in the battery pack 10 shown in Figure 1. The X direction, Y direction, and Z direction shown in Figures 2 and 3 do not have to coincide with the X direction, Y direction, and Z direction shown in Figure 1, respectively. For example, the battery module 100 shown in Figures 2 and 3 may be mounted in the battery pack 10 shown in Figure 1 in a state where the X direction and Y direction shown in Figures 2 and 3 coincide with the Y direction and X direction shown in Figure 1, respectively.

[0027] 2 and 3, the battery pack 10 further includes a bracket 300, a heat insulating sheet 400, and wiring 500. As shown in FIGS. 2 and 3, the upper plate 230 includes a first plate portion 231, a second plate portion 232, a third plate portion 233, a fourth plate portion 234, and a fifth plate portion 235. As shown in FIG. 2, the bracket 300 includes a first bracket portion 310, a second bracket portion 320, and a third bracket portion 330.

[0028] 2 and 3, the first bracket portion 310 is located on the +Z side of the battery module 100. The first bracket portion 310 is a member that at least partially overlaps with the battery module 100 in the Z direction. In the example shown in FIG. 2, the first bracket portion 310 is disposed approximately perpendicular to the Z direction. The shape and arrangement of the first bracket portion 310 are not limited to the example shown in FIG. 2.

[0029] As shown in FIG. 2 , a plurality of protrusions 340 are provided on the +Z side surface of the first bracket portion 310. In the example shown in FIG. 2 , two protrusions 340 are provided on the +Y side portion of the +Z side surface of the first bracket portion 310. In the example shown in FIG. 2 , the two protrusions 340 are aligned in the X direction, and the wiring 500 penetrates the two wirings 500 in the X direction. The wiring 500 is, for example, a harness electrically connected to the battery module 100 or a harness electrically connected to an electrical element such as a voltage detection device electrically connected to the battery module 100. In the example shown in FIG. 2 , the wiring 500 is routed in the X direction by the two protrusions 340, with the wiring 500 and each protrusion 340 attached to each other. The number and arrangement of the protrusions 340 and the number and routing of the wirings 500 are not limited to the example shown in FIG. 2 . For example, the number of protrusions 340 may be one or more. The wiring 500 may be routed not only in the X direction but also in any direction perpendicular to the Z direction. Two or more wires 500 may be routed on the +Z side of the +Z side surface of the first bracket portion 310. In place of or in addition to the wires 500, an electronic element such as a printed circuit board (PCB) may be arranged on the +Z side of the +Z side surface of the first bracket portion 310.

[0030] As shown in Fig. 2, the second bracket portion 320 and the third bracket portion 330 are located on the +X side and the -X side, respectively, of the battery module 100. As shown in Fig. 2, the second bracket portion 320 and the third bracket portion 330 are drawn out from the +X side end and the -X side end of the first bracket portion 310, respectively. In the example shown in Fig. 2, the second bracket portion 320 and the third bracket portion 330 are arranged substantially perpendicular to the X direction. The shapes and arrangements of the second bracket portion 320 and the third bracket portion 330 are not limited to the example shown in Fig. 2.

[0031] 2 and 3, the first plate portion 231 is located on the +Z side of the battery module 100, with the first bracket portion 310 being at least partially located between the battery module 100 and the first plate portion 231. In the example shown in FIGS. 2 and 3, the first plate portion 231 is disposed substantially perpendicular to the Z direction. The shape and arrangement of the first plate portion 231 are not limited to the example shown in FIG. 1.

[0032] 2 and 3, the second plate portion 232 is located on the +X side with respect to the battery module 100, with the second bracket portion 320 being at least partially located between the battery module 100 and the second plate portion 232. As shown in FIGS. 2 and 3, the third plate portion 233 is located on the -X side with respect to the battery module 100, with the third bracket portion 330 being at least partially located between the battery module 100 and the third plate portion 233. In the example shown in FIGS. 2 and 3, the second plate portion 232 and the third plate portion 233 are disposed approximately perpendicular to the X direction. The shapes and arrangements of the second plate portion 232 and the third plate portion 233 are not limited to the example shown in FIG. 1.

[0033] 2, the fourth plate portion 234 and the fifth plate portion 235 are located on the +Y side and the -Y side, respectively, of the battery module 100. In the example shown in Fig. 2, the fourth plate portion 234 and the fifth plate portion 235 are arranged substantially perpendicular to the Y direction. The shapes and arrangements of the fourth plate portion 234 and the fifth plate portion 235 are not limited to the examples shown in Figs. 2 and 3.

[0034] The heat insulating sheet 400 is a heat insulating material that protects components surrounding the battery module 100 from relatively high-temperature gases and flames generated by the battery module 100 in the event of an abnormality in the battery module 100, and from high-voltage components, if any, installed in the battery pack 10. The heat insulating sheet 400 has thermal and electrical insulation properties. The heat insulating sheet 400 is, for example, aerogel felt. However, the heat insulating sheet 400 is not limited to the materials exemplified here, as long as it is capable of protecting components surrounding the battery module 100 from the gases, flames, and high-voltage components. The heat insulating sheet 400 is at least partially foldable. This allows the heat insulating sheet 400 to be easily deformed according to the shape of the location where it is installed. However, the heat insulating sheet 400 does not have to be foldable.

[0035] As shown in FIGS. 2 and 3, the heat insulating sheet 400 includes a fixed sheet portion 410 and a pull-out sheet portion 420. As shown in FIGS. 2 and 3, the fixed sheet portion 410 is located on the +Z side of the +Y side portion of the +Z side surface of the first bracket portion 310. As shown in FIGS. 2 and 3, the pull-out sheet portion 420 is pulled out from the +Y side end of the fixed sheet portion 410 and hangs down from the +Y side end of the fixed sheet portion 410 toward the -Z side. As shown in FIGS. 2 and 3, the heat insulating sheet 400 at least partially covers the battery module 100 and the bracket 300 with the fixed sheet portion 410 located at least partially on the +Z side of the +Y side portion of the +Z side surface of the first bracket portion 310 and the pull-out sheet portion 420 hanging down from the +Y side end of the fixed sheet portion 410 toward the -Z side. Therefore, the heat insulating sheet 400 can protect the portion of the upper plate 230 located around the battery module 100 from the gases, flames, and high-voltage components.

[0036] As shown in FIG. 2 , the fixing sheet 410 and the first bracket 310 are attached to each other with multiple protrusions 340 penetrating the fixing sheet 410 in the Z direction. Therefore, the multiple protrusions 340 form a structure that locks the fixing sheet 410 while the heat insulating sheet 400 at least partially covers the battery module 100 and the bracket 300. By locking the fixing sheet 410 with the multiple protrusions 340, the fixing sheet 410 and the first bracket 310 can be attached to each other without bonding them to each other via adhesive. Therefore, compared to when adhesive is used, the workability of installing the heat insulating sheet 400 can be improved. Furthermore, when adhesive is not required, damage such as melting of the adhesive due to gas or flame generated from the battery module 100 can be eliminated, and peeling of the fixing sheet 410 from the first bracket 310 due to adhesive damage can be prevented. Therefore, compared to when adhesive is used, even if gas or flame is generated from the battery module 100, the fixing sheet portion 410 and the first bracket portion 310 can be more easily kept attached to each other by the multiple protrusions 340.

[0037] In the embodiment, the protrusion 340 for attaching the wiring 500 serves as a structure for locking the fixing sheet portion 410. Therefore, the configuration of the bracket 300 can be simplified compared to when a structure for attaching the wiring 500 and a structure for locking the fixing sheet portion 410 are provided separately. However, the structure for attaching the wiring 500 and the structure for locking the fixing sheet portion 410 may be provided separately. The structure for locking the fixing sheet portion 410 is not limited to the protrusion 340 that penetrates the fixing sheet portion 410. The structure for locking the fixing sheet portion 410 may be, for example, a bolt such as a stud bolt that fixes the fixing sheet portion 410 to the first bracket portion 310, or a retainer that holds the fixing sheet portion 410 to the first bracket portion 310.

[0038] 2 and 3, the -Y side surface of the pull-out sheet portion 420 and the +Y side surface of the battery module 100 are not attached to each other. Therefore, the pull-out sheet portion 420 is not constrained by the battery module 100. Therefore, the pull-out sheet portion 420 is at least partially freely disposed relative to the battery module 100. Therefore, the pull-out sheet portion 420 is at least partially freely movable relative to the battery module 100 unless restricted by a member different from the battery module 100.

[0039] 2 and 3 , the pull-out sheet portion 420 is at least partially positioned in the gap between the +Y side surface of the battery module 100 and the −Y side surface of the fourth plate portion 234 when the upper plate 230 at least partially covers the battery module 100 and the bracket 300. Therefore, the fourth plate portion 234 is a structure that restricts movement of the pull-out sheet portion 420 toward the +Y side. Therefore, by adjusting the distance in the Y direction between the +Y side surface of the battery module 100 and the −Y side surface of the fourth plate portion 234, it is possible to adjust the allowable flapping of the pull-out sheet portion 420 between the +Y side surface of the battery module 100 and the −Y side surface of the fourth plate portion 234 due to vibration of the automobile in which the battery pack 10 is mounted. Furthermore, by restricting the movement of the pull-out sheet portion 420 with the fourth plate portion 234, it is possible to arrange the pull-out sheet portion 420 between the +Y side surface of the battery module 100 and the −Y side surface of the fourth plate portion 234 without using an adhesive to bond the pull-out sheet portion 420 and the battery module 100 to each other or to bond the pull-out sheet portion 420 and the fourth plate portion 234 to each other. Therefore, compared to when an adhesive is used, it is possible to improve the workability of installing the heat insulating sheet 400.

[0040] In the example shown in FIGS. 2 and 3 , the +Y-side surface of the battery module 100 and the −Y-side surface of the fourth plate portion 234 are close enough to each other that movement of the draw-out sheet portion 420 toward the +Y-side is restricted, but not close enough to each other that the draw-out sheet portion 420 is compressed in the Y direction by the +Y-side surface of the battery module 100 and the −Y-side surface of the fourth plate portion 234. Therefore, as shown in FIG. 2 , there is at least a partial gap between the +Y-side surface of the draw-out sheet portion 420 and the −Y-side surface of the fourth plate portion 234. This gap is a space where air is present. Therefore, compared to when the draw-out sheet portion 420 and the fourth plate portion 234 are bonded to each other via an adhesive, this gap can more easily insulate the fourth plate portion 234 from gases and flames emitted from the battery module 100 toward the fourth plate portion 234. However, the +Y side surface of the battery module 100 and the -Y side surface of the fourth plate portion 234 may be close to each other to the extent that the pull-out sheet portion 420 is at least partially compressed in the Y direction by the +Y side surface of the battery module 100 and the -Y side surface of the fourth plate portion 234.

[0041] The structure for restricting movement of the withdrawal sheet portion 420 to the +Y side is not limited to the fourth plate portion 234. The structure for restricting movement of the withdrawal sheet portion 420 to the +Y side may be provided separately from the upper plate 230.

[0042] Fig. 4 is a top view of the protrusion 340 according to the embodiment. Fig. 5 is a top view of the slit 430 of the fixed sheet portion 410 according to the embodiment. The X direction, Y direction, and Z direction shown in Figs. 4 and 5 do not have to coincide with the X direction, Y direction, and Z direction shown in Figs. 2 and 3, respectively. For example, the protrusion 340 and the fixed sheet portion 410 shown in Figs. 4 and 5 may be arranged such that the X direction and Y direction shown in Figs. 4 and 5 coincide with the Y direction and X direction shown in Figs. 2 and 3, respectively.

[0043] As shown in FIG. 4, the protrusion 340 has a substantially n-shape when viewed from the Z direction. In the example shown in FIG. 4, the protrusion 340 includes a first extending portion 342, a second extending portion 344, and a third extending portion 346. When viewed from the Z direction, the first extending portion 342 extends in the Y direction. The first extending portion 342 is disposed substantially perpendicular to the X direction. When viewed from the Z direction, the second extending portion 344 extends from the +Y side end of the first extending portion 342 toward the +X side. The second extending portion 344 is disposed substantially perpendicular to the Y direction. When viewed from the Z direction, the third extending portion 346 extends from the -Y side end of the first extending portion 342 toward the +X side. The third extending portion 346 is disposed substantially perpendicular to the Y direction. When the second extension portion 344 and the third extension portion 346 are added to the first extension portion 342, the strength of the protrusion 340 can be improved compared to when the second extension portion 344 and the third extension portion 346 are not added to the first extension portion 342.

[0044] As shown in FIG. 5 , the fixed sheet portion 410 defines a slit 430. When viewed from the Z direction, the slit 430 is substantially H-shaped. The slit 430 includes a first slit portion 432, a second slit portion 434, and a third slit portion 436. When viewed from the Z direction, the first slit portion 432 extends in the Y direction. When viewed from the Z direction, the second slit portion 434 branches into a first branch portion 434a extending from the +Y side end of the first slit portion 432 toward the +X side and a second branch portion 434b extending from the +Y side end of the first slit portion 432 toward the −X side. When viewed from the Z direction, the third slit portion 436 branches into a third branch portion 436a extending from the −Y side end of the first slit portion 432 toward the +X side and a fourth branch portion 436b extending from the −Y side end of the first slit portion 432 toward the −X side.

[0045] The protrusion 340 and the fixing sheet portion 410 are engaged with each other in a state in which the first extending portion 342 penetrates the first slit portion 432 in the Z direction, the second extending portion 344 penetrates the second slit portion 434 in the Z direction, and the third extending portion 346 penetrates the third slit portion 436 in the Z direction. The Y-direction dimension of the first extending portion 342 and the Y-direction dimension of the first slit portion 432 are designed to be approximately equal. The X-direction dimension of the second extending portion 344 and the X-direction dimension of the second slit portion 434 are designed to be approximately equal. The X-direction dimension of the third extending portion 346 and the X-direction dimension of the third slit portion 436 are designed to be approximately equal. Therefore, when the protrusion 340 and the slit 430 are formed as designed, the portion of the fixed sheet portion 410 between the fourth branch portion 436b and the second branch portion 434b is rolled up toward the +Z side along the -X side surface of the first extension portion 342, and the protrusion 340 and the fixed sheet portion 410 are engaged with each other.

[0046] If the slit 430 does not include the second branch portion 434b and the fourth branch portion 436b when viewed in the Z direction and has the same shape as the protrusion 340, the dimension in the X direction of the portion of the fixed sheet portion 410 between the second slit portion 434 and the second slit portion 434 may be relatively large, and the force locking the protrusion 340 and the fixed sheet portion 410 together may be relatively weak. However, in the example shown in Figures 4 and 5, the portion of the fixed sheet portion 410 between the second slit portion 434 and the third slit portion 436 can be divided into the portion between the first branch portion 434a and the third branch portion 436a of the fixed sheet portion 410 and the portion between the second branch portion 434b and the fourth branch portion 436b of the fixed sheet portion 410. Therefore, compared to when the slit 430 does not include the second branch portion 434b and the fourth branch portion 436b and has the same shape as the projection 340, the force that locks the projection 340 and the fixing sheet portion 410 together can be strengthened.

[0047] When the slit 430 does not include the second branch portion 434b and the fourth branch portion 436b and has the same shape as the protrusion 340 when viewed from the Z direction, if the fixed sheet portion 410 is pulled toward the +X side due to factors such as the tolerance of the protrusion 340 and the fixed sheet portion 410, stress is likely to concentrate on the fixed sheet portion 410 around the corner between the -X side surface of the first extending portion 342 of the protrusion 340 and the +Y side surface of the second extending portion 344, and around the corner between the -X side surface of the first extending portion 342 of the protrusion 340 and the -Y side surface of the third extending portion 346, and the fixed sheet portion 410 may be relatively easily torn. However, in the example shown in FIGS. 4 and 5 , even if the fixed sheet portion 410 is pulled toward the +X side, the portion of the fixed sheet portion 410 between the second branch portion 434b and the fourth branch portion 436b is rolled up. Therefore, compared to when the slits 430 and the protrusions 340 have the same shape when viewed in the Z direction, the fixed sheet portion 410 is less likely to break even when pulled toward the +X side.

[0048] 4 and 5 , even if the fixed sheet portion 410 is pulled toward the −X side due to factors such as tolerances of the protrusion 340 and the fixed sheet portion 410, the portion of the fixed sheet portion 410 between the first branch portion 434a and the third branch portion 436a is rolled up. Therefore, even if the fixed sheet portion 410 is pulled toward the −X side, stress is less likely to concentrate on the fixed sheet portion 410 around the +X side end of the second extension portion 344 and around the +X side end of the third extension portion 346, compared to when the portion of the fixed sheet portion 410 between the first branch portion 434a and the third branch portion 436a is not rolled up. Therefore, the fixed sheet portion 410 is less likely to tear, compared to when the portion of the fixed sheet portion 410 between the first branch portion 434a and the third branch portion 436a is not rolled up.

[0049] If the slit 430 does not include the second branch portion 434b and the fourth branch portion 436b and has the same shape as the protrusion 340 when viewed from the Z direction, when the fixed sheet portion 410 is pulled toward the -Y side due to factors such as the tolerance of the protrusion 340 and the fixed sheet portion 410, stress tends to concentrate relatively easily on the fixed sheet portion 410 around the corner between the -X side surface of the first extending portion 342 of the protrusion 340 and the +Y side surface of the second extending portion 344, and the fixed sheet portion 410 may tend to tear relatively easily. However, in the example shown in Figures 4 and 5, the second slit portion 434 is branched into the first branch portion 434a and the second branch portion 434b. Therefore, even when the fixed sheet portion 410 is pulled toward the -Y side, stress is less likely to concentrate on the fixed sheet portion 410 around the corner between the -X side surface of the first extending portion 342 of the protrusion 340 and the +Y side surface of the second extending portion 344, compared to when the slits 430 and the protrusions 340 have the same shape when viewed from the Z direction. Therefore, even when the fixed sheet portion 410 is pulled toward the -Y side, the fixed sheet portion 410 is less likely to tear, compared to when the slits 430 and the protrusions 340 have the same shape when viewed from the Z direction. The same is true when the fixed sheet portion 410 is pulled toward the +Y side due to factors such as tolerances of the protrusions 340 and the fixed sheet portion 410.

[0050] The shape of the slit 430 is not limited to the example shown in Fig. 5. For example, when viewed from the Z direction, the slit 430 may not include the second branch portion 434b and the fourth branch portion 436b and may have substantially the same shape as the shape of the protrusion 340. The branches of the second slit portion 434 and the third slit portion 436 are not limited to the example shown in Fig. 5. When viewed from the Z direction, the multiple branches of the second slit portion 434 can branch in different directions from each other. The same applies to the third slit portion 436.

[0051] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted. [Explanation of symbols]

[0052] 10 battery pack, 100 battery module, 200 housing, 210 lower plate, 220 side frame, 230 upper plate, 231 first plate portion, 232 second plate portion, 233 third plate portion, 234 fourth plate portion, 235 fifth plate portion, 240 support frame, 300 bracket, 310 first bracket portion, 320 second bracket portion, 330 third bracket portion, 340 protrusion, 342 first extension portion, 344 second extension portion, 346 third extension portion, 400 heat insulating sheet, 410 fixed sheet portion, 420 pull-out sheet portion, 430 slit, 432 first slit portion, 434 second slit portion, 434a first branch portion, 434b second branch portion, 436 third slit portion, 436a third branch portion, 436b fourth branch portion, 500 wiring

Claims

1. A battery module; Heat insulating material; a structure that at least partially holds the heat insulating material in a state where the heat insulating material at least partially covers the battery module; A battery pack comprising:

2. The battery pack according to claim 1 , wherein the structure penetrates the thermal insulation.

3. the thermal insulation defines a slit through which the structure extends; The battery pack according to claim 2 , wherein the slit is at least partially branched.

4. The battery pack according to any one of claims 1 to 3, further comprising wiring attached to the structure.

5. Further, a housing for accommodating the battery module is provided.

4. The battery pack according to claim 1, wherein the heat insulating material is at least partially located between the battery module and the housing.

6. 4. The battery pack according to claim 1, wherein the structure is provided on a member that at least partially overlaps the battery pack.

Images