Battery pack

Abstract

A battery pack (1) comprises: a first battery module (10a) and a second battery module (10b); and a shielding member that at least partially shields, from each other, a first discharge hole (125a) for discharging a substance generated from the first battery module (10a) and a second discharge hole (125b) for discharging a substance generated from the second battery module (10b).

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.

[0003] Patent Document 1 describes a bus bar assembly. The bus bar assembly includes a main body portion provided with a discharge groove. High-temperature gas discharged from a battery cell is discharged through the discharge groove.

[0004] Specification of China Utility Model No. 218448339

[0005] A battery module may have a discharge structure such as a discharge hole for discharging substances such as gas and solid ejected matter generated due to factors such as abnormality of battery cells included in the battery module. In a battery pack, it may be necessary to suppress the influence of substances discharged from the discharge structure of one battery module on other battery modules.

[0006] An example of the object of the present invention is to suppress the influence of substances discharged from a discharge structure of a battery module on other battery modules. Other objects of the present invention will become apparent from the description of the present specification.

[0007] One aspect of the present invention is as follows. 1. A battery pack comprising: a plurality of battery modules; and a shielding member that at least partially shields discharge structures for discharging substances generated from the plurality of battery modules from each other. 2. The battery pack according to 1, wherein the shielding member has a structure located at least partially between the discharge structures. 3. The battery pack according to 1, wherein the shielding member has a covering member that openably covers at least one of the discharge structures. 4. The battery pack according to 1, wherein the shielding member includes a compressed elastic material. 5. The battery pack according to 1, wherein the shielding member includes a plurality of plates covering the discharge structures of the plurality of battery modules, and a recessed plate recessed relative to the plurality of plates.

[0008] According to the above embodiment of the present invention, it is possible to suppress the impact of substances discharged from the discharge structure of a battery module on other battery modules.

[0009] This is a perspective view of the battery pack according to Embodiment 1. This is a schematic plan view of the battery pack according to Embodiment 1 with the upper plate removed. This is a cross-sectional view along line A-A in Figure 2. This is a perspective view of the bracket according to Embodiment 1. This is a diagram showing a first modified example of the bracket shown in Figure 4. (a) is a diagram showing a second modified example of the bracket 50A shown in Figure 4, and (b) is a front view of the battery module to which the bracket shown in (a) is attached. This is a diagram showing a modified example of Figure 3. This is a top view of a part of the battery pack according to Embodiment 2. This is a diagram showing a first modified example of Figure 8. This is a diagram showing a second modified example of Figure 8. This is a top view of a part of the battery pack according to Embodiment 3. This is a cross-sectional view along line B-B in Figure 11. This is a diagram showing a first modified example of Figure 12. This is a diagram showing a second modified example of Figure 12.

[0010] Embodiments and modified examples of the present invention will be described below with reference to the drawings. In all drawings, similar components are denoted by the same reference numerals, and their descriptions are omitted where appropriate.

[0011] Figure 1 is a perspective view of the battery pack 1 according to Embodiment 1. Figure 2 is a schematic plan view of the battery pack 1 according to Embodiment 1 with the upper plate 23 removed. Figure 3 is a cross-sectional view along line A-A in Figure 2. Figure 4 is a perspective view of the bracket 50A according to Embodiment 1.

[0012] In Embodiment 1, the battery pack 1 is mounted in an automobile. Specifically, the battery pack 1 is mounted between the front and rear wheels of the automobile. Hereafter, unless otherwise specified, the battery pack 1 will be described as being mounted in an automobile. However, the battery pack 1 can also be applied to applications other than automobiles.

[0013] Each figure shows the X, Y, and Z axes for illustrative purposes. In Figure 2, the white circle with a black dot indicating the Z axis indicates that the Z-axis arrow is pointing towards the front of the page. In Figure 3, the white circle with a black dot indicating the X axis indicates that the X-axis arrow is pointing towards the front of the page. The X direction indicates the front-to-back direction of the battery pack 1. The Y direction is perpendicular to the X direction. The Y direction indicates the left-to-right direction of the battery pack 1. 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 1. The arrows on the X, Y, and Z axes indicate the front, left, and up directions of the battery pack 1, respectively. The relationship between the X, Y, and Z directions and the front-to-back, left-to-right, and up-to-down directions of the battery pack 1 is not limited to this example.

[0014] In Embodiment 1, the front-to-back, left-to-right, and up-to-down directions of the battery pack 1 are determined by the vehicle on which the battery pack 1 is mounted. The X, Y, and Z directions represent the front-to-back, left-to-right, and up-to-down directions of the vehicle, respectively. The arrows on the X, Y, and Z axes represent the front, left, and up directions of the vehicle, respectively. However, the relationship between the front-to-back, left-to-right, and up-to-down directions of the battery pack 1 and the front-to-back, left-to-right, and up-to-down directions of the vehicle is not limited to this example.

[0015] Unless otherwise specified, the +X side or +X refers to the side indicated by the arrow on the X axis, and the -X side or -X refers to the opposite side of the side indicated by the arrow on the X axis. Unless otherwise specified, the +Y side or +Y refers to the side indicated by the arrow on the Y axis, and the -Y side or -Y refers to the opposite side of the side indicated by the arrow on the Y axis. Unless otherwise specified, the +Z side or +Z refers to the side indicated by the arrow on the Z axis, and the -Z side or -Z refers to the opposite side of the side indicated by the arrow on the Z axis.

[0016] The battery pack 1 according to Embodiment 1 will be described with reference to Figures 1 to 3.

[0017] As shown in Figures 1 to 3, the battery pack 1 comprises multiple battery modules 10, a pack housing 20, two cables 30, a guide member 40, and a bracket 50A. In Figure 2, for the sake of simplification, the first flange 123a, the second flange 124a, the two cables 30, and the guide member 40 shown in Figure 3 are omitted.

[0018] In the example shown in Figure 2, the battery pack 1 comprises four battery modules 10 arranged in two rows and two columns in the X and Y directions, respectively. Hereinafter, the first battery module 10a refers to the battery module 10 located on the +X-Y side, the second battery module 10b refers to the battery module 10 located on the +X+Y side, the third battery module 10c refers to the battery module 10 located on the -X-Y side, and the fourth battery module 10d refers to the battery module 10 located on the -X+Y side. The number and position of the battery modules 10 are not limited to the example shown in Figure 2. For example, the battery pack 1 may comprise a single battery module 10, or it may comprise two, three, or five or more battery modules 10.

[0019] As shown in Figures 2 and 3, each battery module 10 has a plurality of battery cells 11 and a module housing 12.

[0020] As can be seen from Figure 3, in Embodiment 1, the multiple battery cells 11 of each battery module 10 are stacked in the Y direction. The multiple battery cells 11 are connected to each other in series, parallel, or a combination of series and parallel. In Embodiment 1, each battery cell 11 has a substantially rectangular parallelepiped shape with a pair of faces substantially perpendicular to the X direction, a pair of faces substantially perpendicular to the Y direction, and a pair of faces substantially perpendicular to the Z direction. The side lengths of each battery cell 11 are longer in the order of sides substantially parallel to the Y direction, sides substantially parallel to the Z direction, and sides substantially parallel to the X direction. The layout of the multiple battery cells 11 and the shape of each battery cell 11 are not limited to the examples described above.

[0021] The module housing 12 houses a plurality of battery cells 11. As shown in Figures 2 and 3, the module housing 12 includes a first plate 121, a second plate 122, a third plate 123, a fourth plate 124, a fifth plate 125, and a sixth plate (not shown) that cover the +X side, -X side, +Y side, -Y side, +Z side, and -Z side of the plurality of battery cells 11, respectively.

[0022] As shown in Figure 3, the third plate 123 of the first battery module 10a is provided with a first flange 123a protruding toward the +Y side. The fourth plate 124 of the second battery module 10b is provided with a second flange 124a protruding toward the -Y side. The third plate 123 of the third battery module 10c is also provided with a first flange 123a in the same manner as the third plate 123 of the first battery module 10a. The fourth plate 124 of the fourth battery module 10d is also provided with a second flange 124a in the same manner as the fourth plate 124 of the second battery module 10b.

[0023] As shown in Figures 2 and 3, the approximate center of the +Y side end of the fifth plate 125 of the first battery module 10a in the X direction defines the first discharge hole 125a. The approximate center of the -Y side end of the fifth plate 125 of the second battery module 10b in the X direction defines the second discharge hole 125b. In each battery module 10, a malfunction of the battery cell 11 may cause substances such as gas or solid ejecta to be generated from the battery cell 11. Substances generated from the battery cell 11 of the first battery module 10a are discharged from the first battery module 10a through the first discharge hole 125a. Therefore, the first discharge hole 125a is an discharge structure for discharging substances generated from the first battery module 10a. Similarly, the second discharge hole 125b is an discharge structure for discharging substances generated from the second battery module 10b. As shown in Figure 2, the third battery module 10c is also provided with a first discharge hole 125a, similar to the first battery module 10a. The fourth battery module 10d is also provided with a second discharge hole 125b, similar to the second battery module 10b. The number and location of the discharge structures in each battery module 10 are not limited to the examples shown in Figures 2 and 3. For example, each battery module 10 may define a plurality of discharge holes. The arrangement of the plurality of discharge holes is not particularly limited.

[0024] In Embodiment 1, the discharge structure for discharging material generated from the first battery module 10a is a first discharge hole 125a. The discharge structure is not limited to the first discharge hole 125a. For example, the discharge structure may be defined by a portion of the fifth plate 125 that is thinner in the Z direction. When each battery module 10 is operating normally, the thin portion of the fifth plate 125 is closed without penetrating the fifth plate 125. On the other hand, when an abnormality occurs in any of the battery modules 10, the thin portion of the fifth plate 125 melts due to a relatively high-temperature material generated from the battery cell 11, defining a hole. The material generated from the battery cell 11 can be discharged through the hole defined in the thin portion of the fifth plate 125. The same applies to the discharge structures of the other battery modules 10.

[0025] Hereafter, unless otherwise specified, the first discharge port 125a refers to the first discharge port 125a of the first battery module 10a, and the second discharge port 125b refers to the second discharge port 125b of the second battery module 10b. Matters described with respect to the first battery module 10a and the second battery module 10b are also applicable to the third battery module 10c and the fourth battery module 10d.

[0026] As shown in Figures 1 and 2, the pack housing 20 has a lower plate 21, side frames 22, an upper plate 23, and a support frame 24. The lower plate 21 and side frames 22 are sometimes collectively referred to as the lower case. The upper plate 23 is sometimes referred to as the upper case. The pack housing 20 houses a plurality of battery modules 10.

[0027] As shown in Figures 1 and 2, the lower plate 21 is positioned substantially perpendicular to the Z direction. Multiple battery modules 10 are mounted on the +Z side of the lower plate 21. In the example shown in Figures 1 and 2, the lower plate 21 has a longitudinal direction substantially parallel to the X direction and a short direction substantially parallel to the Y direction. The shape of the lower plate 21 is not limited to the example shown in Figures 1 and 2.

[0028] As shown in Figures 1 and 2, the side frame 22 extends from the entire circumference of the +Z plane of the lower plate 21 toward the +Z direction. Viewed from the Z direction, the side frame 22 surrounds the area where the multiple battery modules 10 are located.

[0029] As can be seen from Figures 1 and 2, the upper plate 23 is located on the +Z side relative to the multiple battery modules 10 and the side frame 22. Viewed from the +Z side, the lower plate 21 and the upper plate 23 have substantially the same shape. The side frame 22 and the portion of the upper plate 23 that overlaps with the side frame 22 in the Z direction are fastened to each other by fasteners such as bolts (not shown). With the side frame 22 and the portion of the upper plate 23 that overlaps with the side frame 22 in the Z direction fastened to each other, the lower plate 21, the side frame 22, and the upper plate 23 form a housing space for accommodating the multiple battery modules 10, cables 30, guide members 40, and brackets 50A.

[0030] As shown in Figure 2, when viewed from the Z direction, the support frame 24 extends in a frame shape that at least partially surrounds each battery module 10. Each battery module 10 and the support frame 24 are fastened to each other by fasteners such as bolts (not shown). With each battery module 10 and the support frame 24 fastened to each other, each battery module 10 and the pack housing 20 are attached to each other.

[0031] As shown in Figure 3, the cable 30 is guided in the X direction by a guide member 40 between the first battery module 10a and the second battery module 10b. In the example shown in Figure 3, the guide member 40 is located on the +Z side with respect to the first flange 123a of the first battery module 10a and the second flange 124a of the second battery module 10b. The guide member 40 is fixed in place, for example, with the set of the first flange 123a of the first battery module 10a and the second flange 124a of the second battery module 10b attached to each other. In the example shown in Figure 3, the +Z side portion of the guide member 40 defines two guide grooves 41 that guide two cables 30 aligned in the Y direction. The number of cables 30 located between the first battery module 10a and the second battery module 10b is not limited to two; it may be only one, or three or more.

[0032] A bracket 50A according to an embodiment will be described with reference to Figures 2 to 4.

[0033] As shown in Figures 3 and 4, the bracket 50A includes a first cover plate 51A, a second cover plate 52A, and a recessed plate 53A. The recessed plate 53A includes a first side cover plate 531A, a second side cover plate 532A, and a bottom cover plate 533A.

[0034] As shown in Figures 2 and 3, the first cover plate 51A covers the approximately central portion in the X direction of the +Y side end of the fifth plate 125 of the first battery module 10a, including the first discharge hole 125a. As shown in Figures 2 and 3, the second cover plate 52A covers the approximately central portion in the X direction of the -Y side end of the fifth plate 125 of the second battery module 10b, including the second discharge hole 125b.

[0035] As shown in Figure 3, the recessed plate 53A is located between the first cover plate 51A and the second cover plate 52A. The recessed plate 53A is recessed to the -Z side relative to the first cover plate 51A and the second cover plate 52A. The first side cover plate 531A extends from the +Y side end of the first cover plate 51A to the -Z side and is located between the third plate 123 and the guide member 40 of the first battery module 10a. The second side cover plate 532A extends from the -Y side end of the second cover plate 52A to the -Z side and is located between the fourth plate 124 and the guide member 40 of the second battery module 10b. The bottom cover plate 533A extends between the -Z end of the first side cover plate 531A and the -Z end of the second side cover plate 532A, and is located between the set of the first flange 123a of the first battery module 10a and the second flange 124a of the second battery module 10b, and the guide member 40. The bracket 50A is fixed, for example, to the set of the first flange 123a of the first battery module 10a and the second flange 124a of the second battery module 10b, and the bottom cover plate 533A, which are attached to each other.

[0036] In Embodiment 1, the first cover plate 51A, the second cover plate 52A, the first side cover plate 531A, and the second side cover plate 532A are structures that are at least partially located between the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b. Therefore, the bracket 50A is a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Consequently, compared to the case where the bracket 50A is not provided, the influence of substances such as gas and solid ejecta generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances such as gas and solid ejecta generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0037] Specifically, in Embodiment 1, the gas discharged from the first discharge hole 125a of the first battery module 10a can be rectified by the first cover plate 51A and the first side cover plate 531A to the +X side, -X side, or -Y side from the space between the first cover plate 51A and the first discharge hole 125a. Therefore, the gas discharged from the first discharge hole 125a can be shielded from the second discharge hole 125b of the second battery module 10b. Furthermore, solid ejecta discharged from the first discharge hole 125a can be shielded from the second discharge hole 125b by the first cover plate 51A and the first side cover plate 531A. In addition, the first cover plate 51A can prevent gas, solid ejecta, etc. discharged from the second discharge hole 125b of the second battery module 10b from entering the first discharge hole 125a.

[0038] Furthermore, in Embodiment 1, the gas discharged from the second discharge port 125b of the second battery module 10b can be rectified by the second cover plate 52A and the second side cover plate 532A to the +X side, -X side, or +Y side from the space between the second cover plate 52A and the second discharge port 125b. Thus, the gas discharged from the second discharge port 125b can be shielded from the first discharge port 125a of the first battery module 10a. Furthermore, solid ejecta discharged from the second discharge port 125b can be shielded from the first discharge port 125a by the second cover plate 52A and the second side cover plate 532A. In addition, the second cover plate 52A can prevent gas, solid ejecta, etc. discharged from the first discharge port 125a of the first battery module 10a from entering the second discharge port 125b.

[0039] In Embodiment 1, the bracket 50A is made of metal. Therefore, the strength of the bracket 50A can be made relatively high, and the heat resistance of the bracket 50A can be ensured against relatively high temperature substances discharged from the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b. The material constituting the bracket 50A is not limited to metal, for example, as long as the strength of the bracket 50A is made relatively high and the heat resistance of the bracket 50A can be ensured against relatively high temperature substances discharged from the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b.

[0040] In Embodiment 1, the guide member 40 and the bracket 50A are separate components. However, the guide member 40 and the bracket 50A may be integrated. In other words, the bracket 50A may be at least a part of the guide member for guiding the cable 30.

[0041] Figure 5 shows a first modified example of the bracket 50A shown in Figure 4.

[0042] As shown in FIG. 5, the dimensions in the Y direction of the first cover plate 51A and the second cover plate 52A may be relatively long. In the example shown in FIG. 5, the dimension in the Y direction of each of the first cover plate 51A and the second cover plate 52A is longer than the dimension in the Y direction of the recessed plate 53A. Also in the example shown in FIG. 5, compared with the case where the bracket 50A is not provided, the influence of substances such as gas and solid ejecta generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances such as gas and solid ejecta generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0043] FIG. 6(a) is a diagram showing a second modified example of the bracket 50A shown in FIG. 4. FIG. 6(b) is a front view of the battery module 10 to which the bracket 50A shown in FIG. 6(a) is attached.

[0044] The bracket 50A shown in FIGS. 6(a) and 6(b) includes a cover plate 54A, a first side cover plate 55A and a second side cover plate 56A. As shown in FIG. 6(b), the cover plate 54A extends from one end to the other end of the fifth plate 125 in the Y direction. The first side cover plate 55A extends from the +Y side end of the cover plate 54A toward the -Z side, and covers the +Z side portion of the third plate 123. The second side cover plate 56A extends from the -Y side end of the cover plate 54A toward the -Z side, and covers the +Z side portion of the fourth plate 124.

[0045] The bracket 50A shown in Figure 6(a) can be provided on each of the first battery module 10a and the second battery module 10b. When the battery module 10 shown in Figure 6(b) is the first battery module 10a, the +Y side portion of the cover plate 54A and the first side cover plate 55A function as structures that are at least partially located between the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b, similar to the first cover plate 51A and the first side cover plate 531A in the embodiment. When the battery module 10 shown in Figure 6(b) is the second battery module 10b, the -Y side portion of the cover plate 54A and the second side cover plate 56A function as structures that are at least partially located between the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b, similar to the second cover plate 52A and the second side cover plate 532A in the embodiment. Therefore, the bracket 50A shown in Figures 6(a) and 6(b) serves as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, compared to a case where the bracket 50A shown in Figure 6(a) is not provided on the first battery module 10a and the second battery module 10b, the influence of substances such as gas and solid ejecta generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances such as gas and solid ejecta generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0046] Figure 7 shows a modified version of Figure 3.

[0047] As shown in Figure 7, the bottom cover plate 533A may be located on the +Z side with respect to the two cables 30. In the example shown in Figure 7, the bracket 50A is fixed in a state where, for example, the first cover plate 51A and the upper plate 23 are attached to each other, and the second cover plate 52A and the upper plate 23 are attached to each other.

[0048] Also in the example shown in Fig. 7, the first cover plate 51A, the second cover plate 52A, the first side cover plate 531A, and the second side cover plate 532A form a structure that is located at least partially between the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b. Accordingly, the bracket 50A serves as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Therefore, compared to a case where the bracket 50A is not provided, the influence of substances such as gas and solid ejecta generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances such as gas and solid ejecta generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0049] Fig. 8 is a top view of a part of the battery pack 1 according to the second embodiment. The battery pack 1 according to the second embodiment is the same as the battery pack 1 according to the first embodiment except for the following points.

[0050] In the second embodiment, a first heat-resistant sheet 51B is provided on the +Z surface side of the fifth plate 125 of the first battery module 10a. The first heat-resistant sheet 51B includes a first fixed portion 511B and a first movable portion 512B. The first fixed portion 511B is located on the +X side with respect to the first discharge hole 125a. The first fixed portion 511B and the fifth plate 125 of the first battery module 10a are fixed to each other via a bonding material such as an adhesive, for example. The first movable portion 512B extends from the first fixed portion 511B to the -X side. The first discharge hole 125a and the first movable portion 512B overlap each other in the Z direction. The fifth plate 125 of the first battery module 10a and the first movable portion 512B are not fixed to each other. Accordingly, the first movable portion 512B is free with respect to the fifth plate 125 of the first battery module 10a. Therefore, the first movable portion 512B serves as a covering member that openably covers the first discharge hole 125a.

[0051] In Embodiment 2, a second heat-resistant sheet 52B is provided on the +Z side of the fifth plate 125 of the second battery module 10b. The second heat-resistant sheet 52B includes a second fixed portion 521B and a second movable portion 522B. The second heat-resistant sheet 52B is similar to the first heat-resistant sheet 51B, except that it is substantially symmetrical with the first heat-resistant sheet 51B with respect to an axis passing through the approximate center in the Y direction of the region between the first battery module 10a and the second battery module 10b in the X direction.

[0052] In Embodiment 2, when solid ejected material is discharged from the first discharge hole 125a of the first battery module 10a, the pressure of the solid ejected material causes the first movable part 512B to rotate so that the -X side end of the first movable part 512B moves toward the +Z side, with the +X side end of the first movable part 512B and the first fixed part 511B fixed to each other. As the first movable part 512B rotates, the first discharge hole 125a is opened from the first movable part 512B. As the first discharge hole 125a is opened, solid ejected material is discharged from the first discharge hole 125a to the area around it. The second discharge hole 125b of the second battery module 10b remains closed by the second movable part 522B even when the first discharge hole 125a is opened from the first movable part 512B. Therefore, the second movable part 522B acts as a shielding member that at least partially shields the first discharge hole 125a and the second discharge hole 125b from each other. Thus, compared to the case where the second heat-resistant sheet 52B is not provided, the impact of substances discharged from the first discharge hole 125a of the first battery module 10a on the second battery module 10b can be suppressed.

[0053] In Embodiment 2, when solid ejected material is discharged from the second discharge hole 125b of the second battery module 10b, the pressure of the solid ejected material causes the second movable part 522B to rotate such that the -X side end of the second movable part 522B moves toward the +Z side, with the +X side end of the second movable part 522B and the second fixed part 521B fixed to each other. As the second movable part 522B rotates, the second discharge hole 125b is opened from the second movable part 522B. As the second discharge hole 125b is opened, solid ejected material is discharged from the second discharge hole 125b to the area around it. The first discharge hole 125a of the first battery module 10a remains closed by the first movable part 512B even when the second discharge hole 125b is opened from the second movable part 522B. Therefore, the first movable part 512B acts as a shielding member that at least partially shields the first discharge hole 125a and the second discharge hole 125b from each other. Thus, compared to the case where the first heat-resistant sheet 51B is not provided, the impact of substances discharged from the second discharge hole 125b of the second battery module 10b on the first battery module 10a can be suppressed.

[0054] The material constituting the first heat-resistant sheet 51B is not particularly limited, as long as the first heat-resistant sheet 51B has heat resistance to the relatively high-temperature gas discharged from the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b. The same applies to the material constituting the second heat-resistant sheet 52B.

[0055] Figure 9 shows the first modified example of Figure 8.

[0056] As shown in Figure 9, the first movable portion 512B may cover the first discharge hole 125a with the first fixed portion 511B positioned on the +Y side relative to the first discharge hole 125a. In the example shown in Figure 9, the first fixed portion 511B and the first movable portion 512B extend in the X direction. The first movable portion 512B is a covering member that covers the first discharge hole 125a in an openable manner. In the example shown in Figure 9, when solid ejected material is discharged from the first discharge hole 125a of the first battery module 10a, the pressure of the solid ejected material causes the first movable portion 512B to rotate such that the -Y side end of the first movable portion 512B moves toward the +Z side, with the +Y side end of the first movable portion 512B and the first fixed portion 511B fixed to each other. As the first movable portion 512B rotates, the first discharge hole 125a is opened from the first movable portion 512B.

[0057] Viewed from the +Z side, the second heat-resistant sheet 52B is similar to the first heat-resistant sheet 51B, except that the first heat-resistant sheet 51B and the second heat-resistant sheet 52B are substantially symmetrical with respect to an axis that passes through the approximate center in the Y direction in the region between the first battery module 10a and the second battery module 10b in the X direction.

[0058] In the example shown in Figure 9, similar to the example shown in Figure 8, the second discharge hole 125b of the second battery module 10b remains closed by the second movable part 522B even when the first discharge hole 125a is opened from the first movable part 512B. Therefore, the second movable part 522B acts as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, compared to the case where the second heat-resistant sheet 52B is not provided, the impact of substances discharged from the first discharge hole 125a of the first battery module 10a on the second battery module 10b can be suppressed.

[0059] In the example shown in Figure 9, similar to the example shown in Figure 8, the first discharge hole 125a of the first battery module 10a remains closed by the first movable part 512B even when the second discharge hole 125b is opened from the second movable part 522B. Therefore, the first movable part 512B acts as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, compared to the case where the first heat-resistant sheet 51B is not provided, the impact of substances discharged from the second discharge hole 125b of the second battery module 10b on the first battery module 10a can be suppressed.

[0060] Figure 10 shows a second modified example of Figure 8.

[0061] In the example shown in Figure 10, viewed from the +Z side, the first movable portion 512B is at least partially surrounded by the first fixed portion 511B. Viewed from the +Z side, the first fixed portion 511B and the first movable portion 512B are separated from each other by the first slit 513B around the first discharge hole 125a, except for the +Y side end of the first movable portion 512B. The first movable portion 512B is free from the fifth plate 125 of the first battery module 10a. Therefore, the first movable portion 512B is a covering member that covers the first discharge hole 125a in an openable manner. In the example shown in Figure 10, when solid ejected material is discharged from the first discharge hole 125a of the first battery module 10a, the pressure of the solid ejected material causes the first movable part 512B to rotate such that the -Y side end of the first movable part 512B moves toward the +Z side, with the +Y side end of the first movable part 512B and the first fixed part 511B fixed to each other. As the first movable part 512B rotates, the first discharge hole 125a is opened from the first movable part 512B.

[0062] In the example shown in Figure 10, when viewed from the +Z side, the second fixed portion 521B and the second movable portion 522B are separated from each other by the second slit 523B around the second discharge hole 125b, except for the -Y side end of the second movable portion 522B. When viewed from the +Z side, the second heat-resistant sheet 52B is similar to the first heat-resistant sheet 51B, except that the first heat-resistant sheet 51B and the second heat-resistant sheet 52B are substantially symmetrical with respect to an axis that passes through the approximate center in the Y direction of the region between the first battery module 10a and the second battery module 10b in the X direction.

[0063] In the example shown in Figure 10, similar to the example shown in Figure 8, the second discharge hole 125b of the second battery module 10b remains closed by the second movable part 522B even when the first discharge hole 125a is opened from the first movable part 512B. Therefore, the second movable part 522B acts as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, compared to the case where the second heat-resistant sheet 52B is not provided, the impact of substances discharged from the first discharge hole 125a of the first battery module 10a on the second battery module 10b can be suppressed.

[0064] In the example shown in Figure 10, similar to the example shown in Figure 8, the first discharge hole 125a of the first battery module 10a remains closed by the first movable part 512B even when the second discharge hole 125b is opened from the second movable part 522B. Therefore, the first movable part 512B acts as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, compared to the case where the first heat-resistant sheet 51B is not provided, the impact of substances discharged from the second discharge hole 125b of the second battery module 10b on the first battery module 10a can be suppressed.

[0065] Figure 11 is a top view of a portion of the battery pack 1 according to Embodiment 3. Figure 12 is a cross-sectional view along the line B-B in Figure 11. The battery pack 1 according to Embodiment 3 is the same as the battery pack 1 according to Embodiment 1, except for the following points.

[0066] As shown in Figure 12, the first elastic material 51C is located between the +Z plane of the fifth plate 125 of the first battery module 10a and the -Z plane of the upper plate 23. The second elastic material 52C is located between the +Z plane of the fifth plate 125 of the second battery module 10b and the -Z plane of the upper plate 23. When the first battery module 10a is housed in the pack housing 20, the first elastic material 51C is compressed in the Z direction by the +Z plane of the fifth plate 125 of the first battery module 10a and the -Z plane of the upper plate 23. When the second battery module 10b is housed in the pack housing 20, the second elastic material 52C is compressed in the Z direction by the +Z plane of the fifth plate 125 of the second battery module 10b and the -Z plane of the upper plate 23.

[0067] As shown in Figure 11, when viewed from the +Z side, the first elastic material 51C is located on the +Y side relative to the first discharge hole 125a. In the example shown in Figure 11, the X-direction dimension of the first elastic material 51C is larger than the X-direction dimension of the first discharge hole 125a. As shown in Figure 11, when viewed from the +Z side, the second elastic material 52C is located on the -Y side relative to the second discharge hole 125b. In the example shown in Figure 11, the X-direction dimension of the second elastic material 52C is larger than the X-direction dimension of the second discharge hole 125b.

[0068] The first elastic material 51C and the second elastic material 52C are at least partially located between the first discharge hole 125a and the second discharge hole 125b. Therefore, the first elastic material 51C and the second elastic material 52C serve as shielding members that at least partially shield the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Thus, substances discharged from the first discharge hole 125a can be shielded from the second discharge hole 125b by the first elastic material 51C and the second elastic material 52C. Similarly, substances discharged from the second discharge hole 125b can be shielded from the first discharge hole 125a by the first elastic material 51C and the second elastic material 52C. Therefore, compared to the case where the first elastic material 51C and the second elastic material 52C are not provided, the influence of substances generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0069] The relatively high temperature of the material discharged from the first discharge hole 125a or the second discharge hole 125b may cause the housing space of the pack housing 20 to expand, and the upper plate 23 may bend to the +Z side. In Embodiment 3, as described above, the first elastic material 51C and the second elastic material 52C are compressed in the Z direction before the housing space of the pack housing 20 expands. Therefore, even if the housing space of the pack housing 20 expands and the upper plate 23 bends to the +Z side, the first elastic material 51C and the second elastic material 52C expand due to their elasticity in accordance with the bending of the upper plate 23. Consequently, the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b can continue to be shielded from each other by the first elastic material 51C and the second elastic material 52C.

[0070] The first elastic material 51C and the second elastic material 52C are materials that include, for example, at least one of a foaming material and a thermal expansion material. Silicone foam is an example of such material. Preferably, the first elastic material 51C and the second elastic material 52C have heat resistance to relatively high temperature substances discharged from the first discharge hole 125a or the second discharge hole 125b. When the first elastic material 51C and the second elastic material 52C include at least one of a foaming material and a thermal expansion material, when the housing space of the pack housing 20 expands due to the relatively high temperature substance discharged from the first discharge hole 125a or the second discharge hole 125b, the first elastic material 51C and the second elastic material 52C expand not only due to their elasticity but also due to their thermal expansion. Therefore, even if the housing space of the pack housing 20 expands and the upper plate 23 curves to the +Z side, the first elastic material 51C and the second elastic material 52C expand in accordance with the curvature of the upper plate 23. Thus, the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b can continue to be shielded from each other by the first elastic material 51C and the second elastic material 52C.

[0071] The first elastic material 51C and the second elastic material 52C may be elastic materials that do not contain foaming material or thermal expansion material. Even if the first elastic material 51C and the second elastic material 52C do not contain foaming material or thermal expansion material, in Embodiment 3, the first elastic material 51C and the second elastic material 52C are compressed in the Z direction before the housing space of the pack housing 20 expands. Therefore, even if the housing space in the pack housing 20 expands and the upper plate 23 curves to the +Z side, the first elastic material 51C and the second elastic material 52C expand due to the elasticity of the first elastic material 51C and the second elastic material 52C in accordance with the curvature of the upper plate 23. Thus, the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b can continue to be shielded from each other by the first elastic material 51C and the second elastic material 52C.

[0072] Figure 13 shows the first modified example of Figure 12.

[0073] As shown in Figure 13, the elastic material 50C may be positioned between the +Z side end of the guide member 40 and the upper plate 23-Z surface. In the example shown in Figure 13, the two cables 30 and the elastic material 50C overlap each other in the Z direction. Similar to the first elastic material 51C and the second elastic material 52C shown in Figures 11 and 12, the elastic material 50C shown in Figure 13 is compressed in the Z direction by the +Z side end of the guide member 40 and the -Z surface of the upper plate 23. Furthermore, the elastic material 50C is at least partially positioned between the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b. Therefore, the elastic material 50C acts as a shielding member that at least partially shields the first discharge hole 125a of the first battery module 10a and the second discharge hole 125b of the second battery module 10b from each other. Therefore, compared to the case where the elastic material 50C is not provided, the influence of substances generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of substances generated from the second battery module 10b on the first battery module 10a can be suppressed.

[0074] Figure 14 shows a second modified example of Figure 12.

[0075] As shown in Figure 14, when viewed from the +X side, the Y-direction dimension of the elastic material 50C may be less than the distance between the centers of the two guide grooves 41. As shown in Figure 14, even when the Y-direction dimension of the elastic material 50C is relatively small, the influence of material generated from the first battery module 10a on the second battery module 10b can be suppressed, and the influence of material generated from the second battery module 10b on the first battery module 10a can be suppressed, in the same manner as in the example shown in Figure 13, compared to the case where the elastic material 50C is not provided.

[0076] The embodiments and modifications of the present invention have been described above with reference to the drawings, but these are merely examples of the present invention, and various other configurations can also be adopted.

[0077] This application claims priority based on Japanese Patent Application No. 2025-053075, filed on 27 March 2025, and incorporates all of its disclosures herein.

[0078] 1 Battery pack, 10 Battery modules, 10a First battery module, 10b Second battery module, 10c Third battery module, 10d Fourth battery module, 11 Battery cell, 12 Module housing, 121 First plate, 122 Second plate, 123 Third plate, 123a First flange, 124 Fourth plate, 124a Second flange, 125 Fifth plate, 125a First discharge hole, 125b Second discharge hole, 20 Pack housing, 21 Lower plate, 22 Side frame, 23 Upper plate, 24 Support frame, 30 Cable, 40 Guide member, 41 Guide groove, 50A Bracket, 51A First cover plate, 52A Second cover plate, 53A Recessed plate, 531A First side cover plate, 532A Second side cover plate, 533A Bottom cover plate, 54A Cover plate, 55A First side cover plate, 56A Second side cover plate, 51B First heat-resistant sheet, 511B First fixing part, 512B First movable part, 513B First slit, 52B Second heat-resistant sheet, 521B Second fixing part, 522B Second movable part, 523B Second slit, 50C Elastic material, 51C First elastic material, 52C Second elastic material

Claims

1. A battery pack comprising: a plurality of battery modules; and shielding members that at least partially shield each other from each other the discharge structures for discharging substances generated from the plurality of battery modules.

2. The battery pack according to claim 1, wherein the shielding member has a structure that is at least partially located between the discharge structures.

3. The battery pack according to claim 1, wherein the shielding member has a covering member that covers at least one of the discharge structures in an openable manner.

4. The battery pack according to claim 1, wherein the shielding member has a compressed elastic material.

5. The battery pack according to claim 1, wherein the shielding member comprises a plurality of plates covering the discharge structure of the plurality of battery modules, and a recessed plate recessed relative to the plurality of plates.

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