Battery pack

Abstract

A battery pack (10) comprises a battery module (100), a support body (400), and a lower plate (310) positioned between the battery module (100) and the support body (400). The support body (400) defines a space (402).

Description

Battery pack

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

[0002] In recent years, various battery packs have been developed. A battery pack includes a battery module and a housing that houses the battery module.

[0003] Patent Document 1 describes a battery pack. The battery pack includes a battery, a liquid-cooling plate, a honeycomb panel, and a support plate. The honeycomb panel is positioned between the liquid-cooling plate and the support plate.

[0004] Patent Document 2 describes a battery pack. The battery pack is provided with a liquid-cooled plate. An elastic heat-insulating support is bonded to the liquid-cooled plate via an adhesive.

[0005] Chinese Utility Model No. 218513558 Chinese Utility Model No. 209804749

[0006] As described in Patent Documents 1 and 2, battery modules and cooling bodies may be stacked on top of each other. When the battery modules and cooling body are stacked on top of each other, a support may be provided on the side of the cooling body opposite the side where the battery modules are located to suppress deformation of the cooling body due to factors such as the weight of the battery modules. However, simply positioning the cooling body between the battery modules and the support may prevent the support from dissipating heat from the battery modules, making it difficult to efficiently cool the battery modules.

[0007] One object of the present invention is to efficiently cool a battery module with a cooling body positioned between the battery module and the support. Other objects of the present invention will become apparent from the description of this specification.

[0008] An aspect of the present invention is as follows: 1. A battery pack comprising: a battery module; a support; and a cooling body located between the battery module and the support, wherein the support defines a space. 2. The battery pack according to 1., wherein the space forms a path for air flow. 3. The battery pack according to 1. or 2., wherein the space extends in at least one direction. 4. The battery pack according to any one of 1. to 3., wherein the space is defined by a folded portion of the support. 5. The battery pack according to any one of 1. to 3., wherein the space is defined by a hole provided in the support. 6. The battery pack according to any one of 1. to 3., wherein the space is defined between the cooling body and a portion of the support located a predetermined distance away from the cooling body. 7. The battery pack according to any one of 1. to 6., wherein the cooling body has a plurality of plates overlapping each other. 8. 7. The battery pack according to 7., wherein the support body and the plate located on the side where the support body is located are attached to each other.

[0009] According to the above aspect of the present invention, the battery module can be efficiently cooled with the cooling body positioned between the battery module and the support body.

[0010] 1 is a schematic plan view of a battery pack according to an embodiment; FIG. 2 is a cross-sectional view taken along line AA in FIG. 1; FIG. 3 is a cross-sectional view of a lower plate and a plurality of supports taken along line BB in FIG. 1; FIG. 4 is a diagram illustrating a first modified example of FIG. 2; FIG. 5 is a diagram illustrating a second modified example of FIG. 2; and FIG. 6 is a diagram illustrating a third modified example of FIG. 2.

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

[0012] Fig. 1 is a schematic plan view of a battery pack 10 according to an embodiment. Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1. Fig. 3 is a cross-sectional view of a lower plate 310 and a plurality of supports 400 taken along line B-B in Fig. 1. For ease of explanation, the upper plate 330 shown in Fig. 2 has been removed from Fig. 1.

[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, each figure shows the X, Y, and Z directions. 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. 2, 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. In FIG. 3, a white circle with a black dot indicating the Y direction indicates that the arrow pointing to the Y 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-rear direction, left-right direction, and up-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 FIGS. 1 to 3. FIG.

[0018] As shown in FIG. 1 , the battery pack 10 includes a plurality of battery modules 100 , a junction box 200 , a pack housing 300 , and a plurality of supports 400 .

[0019] In the example shown in Fig. 1, four battery modules 100 are arranged in two rows and two columns in the X direction and the Y direction, respectively. The number and arrangement of the battery modules 100 are not limited to the number and arrangement 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 includes 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. As shown in FIG. 1 , each battery module 100 further includes a module housing 110 that houses the battery cells (not shown). Each module housing 110 has a substantially rectangular parallelepiped shape. As shown in FIG. 1 , when viewed from the Z direction, each module housing 110 has a substantially rectangular shape with a pair of sides substantially parallel to the X direction and another pair of sides substantially parallel to the Y direction. As shown in FIG. 1 , protrusions 112 are provided on both sides of each module housing 110 in the Y direction. When viewed from the Z direction, each protrusion 112 extends in the X direction. However, the shape of the protrusions 112 is not limited to the shape shown in FIG. 1 .

[0021] As shown in Fig. 1 , the junction box 200 is located on the +X side of the two battery modules 100 located on the +X side. The position at which the junction box 200 is disposed is not limited to the position shown in Fig. 1 . The multiple battery modules 100 and the junction box 200 are electrically connected by a bus bar (not shown).

[0022] 1 and 2, the pack housing 300 has a lower plate 310, side frames 320, an upper plate 330, and a support frame 340. The pack housing 300 houses a plurality of battery modules 100 and a junction box 200. As shown in FIGS. 2 and 3, the lower plate 310 includes a first lower plate 312 and a second lower plate 314.

[0023] The first lower plate 312 has a generally plate shape that is generally perpendicular to the Z direction. The multiple battery modules 100 and the junction box 200 are located on the +Z side of the +Z side surface of the first lower plate 312. As shown in Fig. 1 , the first lower plate 312 has a generally rectangular shape with a pair of long sides that are generally parallel to the X direction and a pair of short sides that are generally parallel to the Y direction. The shape of the first lower plate 312 is not limited to the example shown in Fig. 1 .

[0024] The first lower plate 312 and the second lower plate 314 overlap each other in the Z direction, with the second lower plate 314 positioned on the −Z side relative to the first lower plate 312. As shown in Figures 2 and 3, the second lower plate 314 defines a recess that is partially recessed toward the −Z side by a bent portion of the second lower plate 314. A flow path 316 is partially defined between the first lower plate 312 and the second lower plate 314 by the recess defined by the bent portion of the second lower plate 314.

[0025] As shown in FIG. 2 , each battery module 100 is located on the +Z side of the +Z side of the first lower plate 312, with the thermally conductive adhesive 150 positioned between the −Z side of the module housing 110 and the +Z side of the first lower plate 312. The −Z side of the module housing 110 and the +Z side of the first lower plate 312 are physically bonded to each other via the thermally conductive adhesive 150 and are thermally coupled to each other via the thermally conductive adhesive 150. Therefore, the thermal conductivity between the battery module 100 and the first lower plate 312 can be improved by the thermally conductive adhesive 150. However, the −Z side of the module housing 110 and the +Z side of the first lower plate 312 may be in direct contact with each other without the thermally conductive adhesive 150.

[0026] A coolant such as water can flow through the flow paths 316. For example, in the cross sections shown in FIGS. 2 and 3 , the coolant can flow through the flow paths 316 from one side to the other in the Y direction. Therefore, when the coolant flows through the flow paths 316, the lower plate 310 can function as a cooler that cools the battery module 100. The coolant flowing through the flow paths 316 is not limited to a liquid such as water, but may also be a gas. The structure of the lower plate 310 is not limited to the example shown in FIGS. 2 and 3 . For example, the lower plate 310 may include three or more plates stacked together in the Z direction. Even when the lower plate 310 includes three or more plates, the lower plate 310 can function as a cooler that cools the battery module 100 when the coolant flows through the flow paths provided inside the lower plate 310.

[0027] The side frame 320 extends toward the +Z side from the entire periphery in the Z direction of the +Z side surface of the first lower plate 312. When viewed from the Z direction, the side frame 320 surrounds the area in which the multiple battery modules 100 and the junction box 200 are located.

[0028] The upper plate 330 is located on the +Z side relative to the multiple battery modules 100, the junction box 200, and the side frame 320. When viewed from the Z direction, the first lower plate 312 and the upper plate 330 have substantially the same shape. The side frame 320 and the portion of the upper plate 330 that overlaps with the side frame 320 in the Z direction are fastened to each other with fasteners such as bolts (not shown). With the side frame 320 and the portion of the upper plate 330 that overlaps with the side frame 320 in the Z direction fastened to each other, the lower plate 310, the side frame 320, and the upper plate 330 form an accommodation space that accommodates the multiple battery modules 100 and the junction box 200.

[0029] As shown in FIG. 1 , when viewed from the Z direction, the support frame 340 extends in a frame shape that at least partially surrounds each battery module 100. As shown in FIG. 1 , when viewed from the Z direction, the support frame 340 includes an extension body 342 located on the +Y side of the +Y-side battery module 100, an extension body 342 located between the +Y-side battery module 100 and the −Y-side battery module 100, and an extension body 342 located on the −Y side of the −Y-side battery module 100. When viewed from the Z direction, each extension body 342 extends in the X direction. As shown in FIG. 2 , each protrusion 112 is located on the +Z side of the +Z-side surface of each extension body 342. The protrusions 112 and each extension body 342 are fastened to each other by fasteners such as bolts (not shown). With the protrusions 112 and each extension body 342 fastened to each other, the battery modules 100 and the pack housing 300 are attached to each other.

[0030] 1 and 3, the plurality of supports 400 are lined up in the X direction. In the example shown in Fig. 1, the support 400 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. However, the shape, number, and arrangement of the plurality of supports 400 are not limited to the examples shown in Figs. 1 to 3.

[0031] As shown in FIGS. 2 and 3 , each support 400 is located on the −Z side relative to the second lower plate 314. As shown in FIG. 2 , both Y-direction end portions of each support 400 are bent toward the +Z side. Both Y-direction end portions of the lower plate 310 and both Y-direction end portions of each support 400 are fastened to each other by fasteners such as bolts (not shown). When both Y-direction end portions of the lower plate 310 and both Y-direction end portions of each support 400 are fastened to each other, the second lower plate 314 and the support 400 are attached to each other. However, the attachment method of the second lower plate 314 and the support 400 is not limited to the example shown in FIG. 2 . When both Y-direction end portions of the lower plate 310 and both Y-direction end portions of each support 400 are fastened to each other, the support 400 supports the lower plate 310 from the side opposite to the side on which the multiple battery modules 100 are located. Therefore, deformation of the lower plate 310 due to factors such as the weight of each battery module 100 can be suppressed by the support body 400. In order to suppress deformation of the lower plate 310, the support body 400 is preferably made of a material with relatively high rigidity. For example, the support body 400 is made of sheet metal such as an aluminum plate.

[0032] As shown in FIG. 2 , each support 400 defines a recess partially recessed toward the −Z side by the bent portion of each support 400. The recess defined by the bent portion of each support 400 partially defines a space 402 between the second lower plate 314 and each support 400. For example, as shown in FIG. 2 , two spaces 402 may exist that overlap two battery modules 100 in the Z direction. As shown in FIG. 3 , each space 402 is open on both sides of each support 400 in the X direction. Therefore, each space 402 communicates with the spaces existing on both sides of each space 402 in the X direction. However, the shape, arrangement, and number of the spaces 402 are not limited to the examples shown in FIGS. 1 to 3 .

[0033] The space 402 forms a flow path for air to flow. For example, when air flows in the X direction while a vehicle equipped with the battery pack 10 is running, some of the air may pass through the space 402. The air flowing through the space 402 can cool the battery module 100. Therefore, compared to when the space 402 does not exist, the battery module 100 can be cooled more efficiently with the lower plate 310 positioned between the battery module 100 and the support body 400. The coolant flowing through the space 402 is not limited to air. A cooling gas other than air may flow through the space 402. Alternatively, a liquid coolant such as water may flow through the space 402.

[0034] 2, the -Z side portion of the second lower plate 314 and the +Z side portion of the space 402 are in direct contact with each other. Therefore, the space 402 can more easily cool the battery module 100 compared to a case where the -Z side portion of the second lower plate 314 and the +Z side portion of the space 402 are not in direct contact with each other. However, the -Z side portion of the second lower plate 314 and the +Z side portion of the space 402 do not have to be in direct contact with each other.

[0035] In the examples shown in Figures 2 and 3, the spaces 402 extend in at least one direction perpendicular to the Z direction. For example, in the cross section shown in Figure 2, each space 402 extends in the Y direction, and in the cross section shown in Figure 3, each space 402 extends in the X direction. By having the spaces 402 extend in a predetermined extension direction, air can flow in the extension direction of the spaces 402. The spaces 402 do not have to extend linearly, and may be partially curved. Furthermore, in the cross section shown in Figure 2, two spaces 402 aligned in the Y direction may be connected to each other.

[0036] Figure 4 is a diagram showing a first modification of Figure 2. The example shown in Figure 4 is similar to the embodiment shown in Figure 2, except for the following points.

[0037] As shown in Fig. 4 , the support body 400A may define spaces 402A by holes formed in the support body 400A. In the example shown in Fig. 4 , a cross section perpendicular to the X direction of each space 402A has a substantially rectangular shape having a pair of long sides substantially parallel to the Y direction and a pair of short sides substantially parallel to the Z direction. The shape of the cross section perpendicular to the X direction of each space 402A is not limited to the example shown in Fig. 4 . In the example shown in Fig. 4 , as in the embodiment, the battery module 100 can be cooled more efficiently with the lower plate 310 positioned between the battery module 100 and the support body 400A, compared to when the space 402A does not exist.

[0038] Figure 5 shows a second variation of Figure 2. The example shown in Figure 5 is similar to the embodiment shown in Figure 2, except for the following points.

[0039] In the example shown in FIG. 5 , the support body 400B has a first support member 410B and a second support member 420B. The first support member 410B has a generally plate shape that is generally perpendicular to the Z direction. The second support member 420B is partially located between the −Z side surface of the second lower plate 314 and the +Z side surface of the first support member 410B. The −Z side surface of the second lower plate 314 and the +Z side surface of the first support member 410B are positioned a predetermined distance apart in the Z direction by the second support member 420B. The second support member 420B can also be considered a spacer that positions the −Z side surface of the second lower plate 314 and the +Z side surface of the first support member 410B at a distance from each other by the Z direction dimension of the second support member 420B. The support body 400B defines a space 402B by an area where the second support body 420B is not located between the −Z side surface of the second lower plate 314 and the +Z side surface of the first support body 410B. In the example shown in Fig. 5, similarly to the embodiment, the battery module 100 can be cooled more efficiently with the lower plate 310 located between the battery module 100 and the support body 400B than when the space 402B does not exist.

[0040] Figure 6 is a diagram showing a third modification of Figure 2. The example shown in Figure 6 is similar to the embodiment shown in Figure 2, except for the following points.

[0041] As shown in Fig. 6, the lower plate 310C may be a single plate. A flow path not shown in Fig. 6 is provided inside the lower plate 310C. When a refrigerant flows through the flow path inside the lower plate 310C, the lower plate 310C can function as a cooling body that cools the battery module 100.

[0042] 6 , the support 400 also supports the lower plate 310C from the side opposite to the side where the multiple battery modules 100 are located. Therefore, the support 400 can suppress deformation of the lower plate 310C due to factors such as the weight of each battery module 100. Furthermore, in the example shown in FIG. 6 , as in the embodiment, the battery module 100 can be cooled more efficiently with the lower plate 310C located between the battery module 100 and the support 400 than when the space 402 is not present.

[0043] Although the embodiments and modifications 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.

[0044] This application claims priority based on Japanese Patent Application No. 2024-005438, filed January 17, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0045] REFERENCE SIGNS LIST 10 battery pack, 100 battery module, 110 module housing, 112 protrusion, 150 thermally conductive adhesive, 200 junction box, 300 pack housing, 310, 310C lower plate, 312 first lower plate, 314 second lower plate, 316 flow path, 320 side frame, 330 upper plate, 340 support frame, 342 extension body, 400, 400A, 400B support, 402, 402A, 402B space, 410B first support member, 420B second support member

Claims

1. A battery pack comprising a battery module, a support, and a cooling body positioned between the battery module and the support, wherein the support defines a space.

2. The battery pack according to claim 1, wherein the space forms a path for air to flow.

3. The battery pack according to claim 1 or 2, wherein the space extends in at least one direction.

4. The battery pack according to any one of claims 1 to 3, wherein the space is defined by a bent portion of the support.

5. The battery pack according to any one of claims 1 to 3, wherein the space is defined by a hole provided in the support.

6. The battery pack according to any one of claims 1 to 3, wherein the space is defined between the cooling body and a portion of the support positioned at a predetermined distance from the cooling body.

7. The battery pack according to any one of claims 1 to 6, wherein the cooling body has a plurality of plates overlapping each other.

8. The battery pack according to claim 7, wherein the support and the plate positioned on the side where the support is located are attached to each other.

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