Battery pack

Abstract

To provide a battery pack capable of promoting smoke evacuation while insulating the case when smoke gas is generated from the top of a battery module.SOLUTION: A battery pack includes: a battery module in which multiple battery cells are arranged in the arrangement direction; and a case housing the battery module. A heat-resistant insulating plate is constituted of a top plate part facing the top surface of the battery module and side plate parts facing the side surface perpendicular to the arrangement direction of the battery modules so that the cross-section perpendicular to the arrangement direction is L-shaped, which is placed on the top of the battery module. The heat-resistant insulating plate is configured to be deformable in the height direction of the battery module.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] The battery pack described in Patent Document 1 has a thermal protection layer on the wall of the high-voltage battery housing in the area where an emergency vent opening is located that can discharge high-temperature gas generated in the event of a battery cell failure from inside the battery cell housing to the high-voltage battery housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2021-528296 Summary of the Invention [Problem to be solved by the invention]

[0004] In a battery pack in which a battery module, in which multiple battery cells are arranged in an array direction, is housed in a case, there was room for improvement in achieving both the insulation of the case and the exhaust of smoke gas when smoke gas is generated from the top surface of the battery module.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a battery pack that can promote smoke exhaust while insulating the case when smoke gas is generated from the top surface of the battery module. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the battery pack of the present invention is a battery pack comprising a battery module in which a plurality of battery cells are arranged in an arrangement direction, and a case for housing the battery module, wherein a heat-resistant insulating plate is placed on the top surface of the battery module and configured so that its cross section perpendicular to the arrangement direction is L-shaped, the cross section being formed by a top plate portion facing an upper surface of the battery module and a side plate portion facing a side surface of the battery module in a direction perpendicular to the arrangement direction, and the heat-resistant insulating plate is configured to be displaceable in the height direction of the battery module.

[0007] As a result, when smoke gas is generated from the top surface of the battery module, the heat-resistant insulating plate can insulate the case, while the heat-resistant insulating plate can guide the smoke gas in any direction to promote exhaustion of the smoke.

[0008] In the above, a guide member for guiding displacement of the heat-resistant insulating plate in the height direction may be provided at a position facing the battery modules across the side plate portion in a direction perpendicular to the arrangement direction.

[0009] This allows the heat-resistant insulating plate to be smoothly displaced in the height direction of the battery module by the pressure of the smoke gas when smoke gas is generated from the upper surface of the battery module.

[0010] In the above, the heat-resistant insulating plate may be a mica plate.

[0011] This ensures heat resistance and insulation. Effect of the Invention

[0012] The battery pack of the present invention has the advantage that, when smoke gas is generated from the upper surface of the battery module, the heat-resistant insulating plate insulates the case, while the heat-resistant insulating plate can guide the smoke gas in any direction, thereby promoting smoke exhaust. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic configuration diagram of a main part of a battery pack according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of a part of the battery pack according to the embodiment cut along the arrangement direction of the battery modules. [Diagram 3] FIG. 3 is a cross-sectional view that illustrates the state of the battery pack when smoke gas is generated in any of the multiple battery cells in the battery module. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a battery pack according to the present invention will be described below, however, the present invention is not limited to the embodiment.

[0015] Fig. 1 is a schematic configuration diagram of a main part of a battery pack 1 according to an embodiment. Fig. 2 is a cross-sectional view of a part of the battery pack 1 according to the embodiment cut along the arrangement direction of the battery modules.

[0016] The battery pack 1 according to the embodiment is used as a driving source for vehicles such as BEVs (Battery Electric Vehicles), HEVs (Hybrid Electric Vehicles), and PHEVs (Plug-in Hybrid Electric Vehicles). The direction indicated by the arrow X in FIG. 1 is the arrangement direction of a plurality of battery cells 3 constituting a battery module 4 in the battery pack 1 according to the embodiment. The direction indicated by the arrow Y in FIG. 1 is a direction perpendicular to the arrangement direction X of the battery cells 3, and is the arrangement direction (battery module arrangement direction) of a plurality of battery modules 4 in the battery pack 1 according to the embodiment. The direction indicated by the arrow Z in FIG. 2 is the height direction (vertical direction) of the battery modules 4 in the battery pack 1 according to the embodiment. In the battery pack 1 according to the embodiment, the height direction (vertical direction) of the battery modules 4 is the vertical direction.

[0017] As shown in Fig. 1 and Fig. 2, the battery pack 1 according to the embodiment includes a case 2, a plurality of battery modules 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H, 4I, 4J, 4K, 4L, and a plurality of heat-resistant insulating plates 5A, 5B, 5C, 5D, 5E, 5F, 5G, 5H, 5I, 5J, 5K, 5L. In the battery pack 1 according to the embodiment, the plurality of battery modules 4A, 4B, 4C, 4D, 4E, 4F are configured as a group of battery units, and the plurality of battery modules 4G, 4H, 4I, 4J, 4K, 4L are configured as a group of units. In this embodiment, when the plurality of battery modules 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H, 4I, 4J, 4K, 4L are not particularly distinguished from one another, they are also simply referred to as battery modules 4. In addition, in this embodiment, when there is no particular distinction between the multiple heat-resistant insulating plates 5A, 5B, 5C, 5D, 5E, 5F, 5G, 5H, 5I, 5J, 5K, and 5L, they will be simply referred to as heat-resistant insulating plates 5.

[0018] The case 2 is, for example, a housing formed by a lower case and an upper case 21, and houses a plurality of battery modules 4 and the like.

[0019] Each of the battery modules 4 has a plurality of battery cells 3 arranged along a predetermined direction. Specifically, the battery module 4 is configured by arranging a plurality of battery cells 3 side by side in a predetermined arrangement direction X. The battery cells 3 are configured using, for example, lithium ion secondary batteries.

[0020] The heat-resistant insulating plates 5 are placed on the upper surfaces 41 of the battery modules 4. The heat-resistant insulating plates 5 are configured such that a cross section perpendicular to the arrangement direction X is L-shaped, with a top plate portion 51 facing the upper surface 41 of the battery module 4 and a side plate portion 52 facing a side surface 42 of the battery module 4 in the battery module arrangement direction Y. The battery module 4 has two side surfaces 42, 43 in the battery module arrangement direction Y. The side surface 42 of the battery module 4 is a surface located on the opposite side to a smoke exhaust port 20 (see FIG. 3) provided on one end side of the case 2 described later in the battery module arrangement direction Y. On the other hand, the side surface 43 of the battery module 4 is a surface located on the smoke exhaust port 20 side in the battery module arrangement direction Y. The top plate portion 51 extends in the arrangement direction X and the battery module arrangement direction Y and is formed along the upper surface 41 of the battery module 4. The side plate portion 52 extends in the arrangement direction X and the battery module height direction Z and is formed along the side surface 42 of the battery module 4. The heat-resistant insulating plate 5 is made of a mica plate etc. The heat-resistant insulating plate 5 is simply fixed to the battery module 4 by, for example, a clip which is a fixing member.

[0021] Note that "simply fixed" here refers to a fixation in which, for example, the heat-resistant insulating plate 5 is normally fixed to the battery module 4 by a clip, but the fixation of the heat-resistant insulating plate 5 to the battery module 4 by the clip is released by the pressure of the smoke gas 10 from the battery cell 3 as described below.

[0022] 2, when the heat-resistant insulating plate 5 is placed on the upper surface 41 of the battery module 4, a gap is formed between the upper case 21 of the case 2 and the heat-resistant insulating plate 5 in the battery module height direction Z. This allows the battery pack 1 to be configured such that the heat-resistant insulating plate 5 is displaceable in the battery module height direction Z (vertical direction).

[0023] In the battery pack 1 according to the embodiment, for example, as shown in Fig. 2, battery cross-members 6A, 6B, 6C are provided between adjacent battery modules 4 in the battery module arrangement direction Y. In this embodiment, when there is no need to distinguish between the battery cross-members 6A, 6B, 6C, they will be simply referred to as battery cross-member 6. The battery cross-member 6 is provided on the bottom surface of the lower case of the case 2, extending in the arrangement direction X.

[0024] 2, a cross upper part 7A is provided on a battery cross member 6A that is provided between battery modules 4A and 4B in the battery module arrangement direction Y. The upper end of the cross upper part 7A is located at approximately the same height as the upper surfaces 41A, 41B of the battery modules 4A, 4B in the battery module height direction Z. The top plate portion 51B of the heat-resistant insulating plate 5B placed on the upper surface 41B of the battery module 4B is formed outside the upper surface 41B of the battery module 4B in the battery module arrangement direction Y, extending above the cross upper part 7A and in contact with the upper end of the cross upper part 7A.

[0025] Additionally, a cross upper part 7B is provided on a battery cross member 6B that is provided between the battery modules 4B and 4C in the battery module arrangement direction Y. The upper end of the cross upper part 7B is located at approximately the same height as the upper surfaces 41B, 41C of the battery modules 4B, 4C in the battery module height direction Z. A top plate portion 51C of a heat-resistant insulating plate 5C placed on the upper surface 41C of the battery module 4C is formed outside the upper surface 41C of the battery module 4C in the battery module arrangement direction Y, extending above the cross upper part 7B and in contact with the upper end of the cross upper part 7B.

[0026] Additionally, a cross upper part 7C is provided on a battery cross member 6C provided between the battery modules 4C and 4D in the battery module arrangement direction Y. The upper end of the cross upper part 7C is located at approximately the same height as the upper surfaces 41C, 41D of the battery modules 4C, 4D in the battery module height direction Z. A top plate portion 51D of a heat-resistant insulating plate 5D placed on the upper surface 41D of the battery module 4D is formed outside the upper surface 41D of the battery module 4D in the battery module arrangement direction Y, extending above the cross upper part 7C and in contact with the upper end of the cross upper part 7C.

[0027] In this embodiment, when there is no particular distinction between the battery cross-members 6A, 6B, and 6C, they are also simply referred to as battery cross-members 6. In this embodiment, when there is no particular distinction between the cross upper parts 7A, 7B, and 7C, they are also simply referred to as cross upper parts 7.

[0028] FIG. 3 is a cross-sectional view that illustrates the state of the battery pack 1 when smoke gas 10 is generated in any one of the plurality of battery cells 3 in the battery module 4. As shown in FIG.

[0029] In the battery pack 1 according to the embodiment, the heat-resistant insulating plate 5 is lifted upward in the vertical direction (height direction of the battery module) by the pressure of the smoke gas 10 generated from the upper surface 41 of the battery module 4 (upper surface of the battery cell 3). For example, as shown in FIG. 3, when the smoke gas 10 is generated from the upper surface 41B of the battery module 4B, the heat-resistant insulating plate 5B is lifted upward in the vertical direction by the pressure of the smoke gas 10, and the area of ​​the opening through which the smoke gas 10 passes becomes large. As a result, the heat-resistant insulating plate 5B can be prevented from interfering with the discharge of the smoke gas 10, and the heat-resistant insulating plate 5 can be prevented from being damaged by the pressure of the smoke gas 10. In addition, since there is no need to provide a hole for exhausting smoke in the top plate portion 51 of the heat-resistant insulating plate 5, the load-bearing capacity of the top plate portion 51 of the heat-resistant insulating plate 5 can be improved.

[0030] In the battery pack 1 according to the embodiment, the battery cross member 6 and the cross upper part 7 function as guide members for guiding the displacement of the heat-resistant insulating plate 5 in the battery module height direction Z at positions facing the side surface 42 of the battery module 4 across the side plate portion 52 of the heat-resistant insulating plate 5 in the battery module arrangement direction Y. This allows the heat-resistant insulating plate 5 to be smoothly displaced in the battery module height direction by the pressure of the smoke gas 10 when smoke gas 10 is generated from the upper surface 41 of the battery module 4. Therefore, in the battery pack 1 according to the embodiment, the side plate portion 52 of the heat-resistant insulating plate 5 is guided by the battery cross member 6, the cross upper part 7, and the side surface 42 of the battery module 4, while the heat-resistant insulating plate 5 can be smoothly lifted upward in the vertical direction by the pressure of the smoke gas 10.

[0031] Furthermore, in the battery pack 1 according to the embodiment, after the heat-resistant insulating plate 5 is lifted up, the heat-resistant insulating plate 5 remains above the battery module 4 including the smoking battery cell 3, thereby providing a thermal insulation effect for the upper case 21 of the case 2. This makes it possible to reduce the amount of insulating material provided in the upper case 21 of the case 2, apart from the heat-resistant insulating plate 5.

[0032] 3, for example, in a flow path through which the smoke gas 10 flows, formed between the upper surface 41 of the battery module 4 and the top plate portion 51 of the heat-resistant insulating plate 5, the side plate portion 52 of the heat-resistant insulating plate 5 can restrict the smoke gas 10 from flowing to the opposite side of the smoke exhaust port 20 provided at one end of the case 2 in the battery module arrangement direction Y. In this manner, in the battery pack 1 according to the embodiment, the heat-resistant insulating plate 5 is configured such that the cross section perpendicular to the arrangement direction X is L-shaped by the top plate portion 51 and the side plate portion 52, so that the flow of the smoke gas 10 can be guided toward the smoke exhaust port 20 to promote smoke exhaust.

[0033] In the battery pack 1 according to the embodiment, for example, when no smoke gas 10 is generated from the battery module 4B, the top plate portion 51B of the heat-resistant insulating plate 5B can insulate the top surface 41B of the battery module 4B. In addition, the side plate portion 52B of the heat-resistant insulating plate 5B can insulate the side surface 42B of the battery module 4B and the side surface 43C of the battery module 4C, which face each other across the side plate portion 52B in the battery module arranging direction Y. As a result, in the battery pack 1 according to the embodiment, the minimum area of ​​the heat-resistant insulating plate 5 can insulate the three surfaces of the battery modules 4 adjacent to each other in the battery module arranging direction Y. [Explanation of symbols]

[0034] 1 Battery pack 2 Cases 3 Battery Cells 4 Battery Module 5. Heat-resistant insulating plate 6 Battery cross member 7 Upper cross part 10 Smoke Gas 20 Smoke exhaust vent 21 Upper Case 41 Top side 42,43 Side 51 Top plate 52 Side plate part

Claims

1. A battery module in which a plurality of battery cells are arranged in an arrangement direction; a case for accommodating the battery module; A battery pack comprising: a heat-resistant insulating plate is placed on the upper surfaces of the battery modules, the heat-resistant insulating plate having an L-shaped cross section perpendicular to the arrangement direction, the L-shaped cross section being made up of a top plate portion facing an upper surface of the battery module and a side plate portion facing a side surface of the battery module in a direction perpendicular to the arrangement direction; a heat-resistant insulating plate configured to be displaceable in a height direction of the battery module;

2. 2. The battery pack according to claim 1, further comprising a guide member for guiding displacement of the heat-resistant insulating plate in the height direction, the guide member being disposed opposite the battery module across the side plate portion in a direction perpendicular to the arrangement direction.

3. 3. The battery pack according to claim 1, wherein the heat-resistant insulating plate is a mica plate.

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