Battery pack

Abstract

To provide a battery pack that can adequately protect a battery module against a collision load input through a frame member having a fixing portion with respect to the battery module.SOLUTION: A battery case 20 includes: a first fixing portion 60 that fixes a part of a battery module 10 to a frame member 40 at a position overlapping with an intermediate plate 12 of the battery module 10 when viewed from behind; and a second fixing portion 70 that is provided on the frame member 40 at a position different from the position overlapping with the intermediate plate 12 when viewed from behind and fixes another part of the battery module 10 to the frame member 40. The first fixing portion 60 is configured such that when a load is applied to the first fixing portion 60 and the second fixing portion 70 from behind, the load transmission force to the battery module 10 is greater than the load transmission force of the second fixing portion 70 and the load capacity is greater than the load capacity of the second fixing portion 70.SELECTED DRAWING: Figure 12

Description

[Technical field]

[0001] The present invention relates to a battery pack to be mounted on a vehicle. [Background technology]

[0002] In recent years, research and development has been conducted on secondary batteries (hereafter referred to as batteries) that contribute to energy efficiency in order to ensure that more people have access to affordable, reliable, sustainable and advanced energy.

[0003] Vehicles such as battery-powered electric vehicles, hybrid vehicles, and fuel cell vehicles are equipped with large-capacity batteries. The batteries installed in such vehicles are high-voltage components, so they need to be protected from impacts. However, there is a possibility that a large load may be input to the battery due to a vehicle collision, etc.

[0004] In response to this, for example, Patent Document 1 describes a vehicle body underbody structure that can protect a battery pack arranged under a floor panel during a side collision of the vehicle. The battery side frame of the battery pack described in Patent Document 1 has a structure that effectively transmits the collision load to a battery cross member located on the inside in the vehicle width direction. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-131133 A Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, a frame member constituting the outer frame of the battery pack may be provided with a fixing portion for fixing the battery. In this case, a structure is desired that appropriately protects the battery from a collision load that is input to the battery through the fixing portion when a collision load is input to the frame member.

[0007] The present invention provides a battery pack that can adequately protect a battery module against a collision load input to a frame member that is provided with a fixing portion for the battery module. [Means for solving the problem]

[0008] The present invention relates to A battery module including a plurality of battery cells stacked in a first direction among horizontal directions and a load-bearing member extending in a second direction among the horizontal directions perpendicular to the first direction; A battery pack to be mounted on a vehicle, comprising: a battery case that houses the battery module; The battery case includes: A base plate on which the battery module is mounted; A frame member joined to an outer edge portion of the base plate and constituting an outer frame of the battery case; a first fixing portion provided on the frame member at a position overlapping with the load-bearing member when viewed from the second direction, the first fixing portion fixing a first portion of the battery module to the frame member; a second fixing portion provided on the frame member at a position different from a position overlapping with the load-bearing member when viewed from the second direction, and fixing a second portion of the battery module to the frame member; a tip of the outer edge portion of the base plate as viewed in cross section is disposed below the frame member, the frame member has a vertical wall portion that is located outside the tip of the base plate and extends in the up-down direction so as to overlap the tip of the base plate when viewed from the second direction, The first fixing portion is configured so that when a load in the second direction is applied to the first fixing portion and the second fixing portion, the load transmission force to the battery module is greater than the load transmission force of the second fixing portion, and the load capacity is greater than the load capacity of the second fixing portion. Effect of the Invention

[0009] According to the present invention, it is possible to appropriately protect a battery module against a collision load input to a frame member having a fixing portion for the battery module. [Brief description of the drawings]

[0010] [Figure 1] 1 is a perspective view of a battery pack 1 and a vehicle V on which the battery pack 1 is mounted. [Diagram 2] FIG. 2 is an exploded oblique view of the battery pack 1. [Diagram 3] FIG. 2 is a partial perspective view of the battery module 10. [Figure 4] FIG. 2 is a top view of the battery module 10. [Diagram 5] 2 is a perspective view showing a battery tray 21 and four battery modules 10 placed on the battery tray 21. FIG. [Figure 6] FIG. 2 is a top view showing the internal structure of the battery pack 1. [Figure 7] 2 is a cross-sectional perspective view of a rear cross member 41 and a base plate 30. FIG. [Figure 8] 7 is a cross-sectional view taken along line AA in FIG. 6. [Figure 9] 2 is a perspective view of a first fixing portion 60. FIG. [Figure 10] 7 is a cross-sectional view taken along line BB in FIG. 6. [Figure 11] 2 is a perspective view of a second fixing portion 70. FIG. [Figure 12] 7 is a diagram showing a rotational force T applied to a rear cross member 41 when a collision load is applied from behind, in a cross section taken along the line AA in FIG. 6. FIG. [Figure 13]7 is a diagram showing a rotational force T applied to the rear cross member 41 when a collision load is applied from behind, in the cross section taken along line BB in FIG. 6. FIG. [Figure 14] FIG. 2 is a top view of the battery pack 1 of the first modified example. [Figure 15] FIG. 11 is a top view of the battery pack 1 of the second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A battery pack according to an embodiment of the present invention will be described below with reference to the accompanying drawings. The drawings are to be viewed in the direction of the reference symbols, and in the following description, the front-rear, left-right, and up-down directions are described according to the direction as seen by the driver of the vehicle. In the drawings, the front of the vehicle is indicated as Fr, the rear as Rr, the left as L, the right as R, the upside as U, and the downside as D. The left-right direction is also referred to as the vehicle width direction.

[0012] As shown in Fig. 1, a battery pack 1 according to an embodiment of the present invention is mounted on a vehicle V. The vehicle V is, for example, an electric vehicle such as a battery-powered electric vehicle, a hybrid vehicle, or a fuel cell vehicle. The battery pack 1 is disposed below a floor panel of the vehicle V and attached to the vehicle body.

[0013] As shown in FIG. 2, the battery pack 1 includes four battery modules 10 and a battery case 20 that houses the battery modules 10.

[0014] (Battery module) The four battery modules 10 are arranged in two rows in the front-rear direction and two rows in the left-right direction. The four battery modules 10 are electrically connected to each other via electrical connection members (e.g., bus bars) not shown. The battery modules 10 store electric power to be supplied to a motor or the like that serves as a drive source for the vehicle V. The number of battery modules 10 can be set as desired, and the arrangement is not particularly limited.

[0015] As shown in FIGS. 3 and 4, each battery module 10 includes a plurality of battery cells 11, an intermediate plate 12, a pair of end plates 13, a pair of restraining members 14, and a pair of cover plates 15.

[0016] The battery cell 11 is, for example, a laminated type cell made of a solid-state battery. In this embodiment, a plurality of battery cells 11 are stacked in the left-right direction. The laminated type cell has a positive electrode connected to a positive electrode tab, a negative electrode connected to a negative electrode tab, a solid electrolyte disposed between the positive electrode and the negative electrode, and a laminated film that accommodates these, and charges and discharges by exchanging ions (e.g., lithium ions) between the positive electrode and the negative electrode via the solid electrolyte. Each battery cell 11 is not limited to a laminated type, and may be a square or cylindrical type, and the electrolyte may be liquid or solid.

[0017] The intermediate plate 12 is provided in the middle of the stacking direction (here, the left-right direction) of the multiple battery cells 11, and extends in a direction (here, the front-rear direction) perpendicular to the stacking direction. The intermediate plate 12 is a member having a higher load-bearing capacity than the multiple battery cells 11, and is an example of the load-bearing member of the present invention. Note that two or more intermediate plates 12 may be provided.

[0018] The pair of end plates 13 are provided at both ends in the stacking direction of the multiple battery cells 11, and extend in a direction perpendicular to the stacking direction.

[0019] The pair of restraint members 14 face each other in the vertical direction and are connected to the pair of end plates 13 to restrain the multiple battery cells 11. The pair of restraint members 14 have a plate shape and cover the multiple battery cells 11, the intermediate plate 12, and the pair of end plates 13 from the vertical direction.

[0020] The pair of cover plates 15 are provided outside the multiple battery cells 11 in the front-rear direction, and extend in the stacking direction.

[0021] The cover plate 15 has an intermediate plate connecting portion 152 provided at the central portion 15C in the longitudinal direction (here, the left-right direction) and connects to the intermediate plate 12, and end plate connecting portions 154 provided at the left end portion 15L and the right end portion 15R in the longitudinal direction and connect to a pair of end plates 13.

[0022] Further, a first fixing portion 156 through which a bolt B1 can be inserted from above is provided at the center portion 15C of the cover plate 15. The first fixing portion 156 of the cover plate 15 is fixed to a first fixing portion 60 of the battery case 20 (described later) by the bolt B1. Similarly, a second fixing portion 158 through which a bolt B2 can be inserted from above is provided between the center portion 15C and the left end portion 15L and between the center portion 15C and the right end portion 15R of the cover plate 15. The second fixing portion 158 of the cover plate 15 is fixed to a second fixing portion 70 of the battery case 20 (described later) by the bolt B2. The diameter of the bolt B1 inserted into the first fixing portion 156 is larger than the diameter of the bolt B2 inserted into the second fixing portion 158.

[0023] (Battery case) Returning to FIG. 2, the battery case 20 includes a base plate 30 on which the battery module 10 is placed, a frame member 40 that configures the outer frame of the battery case 20, and a cover 50 that covers the battery module 10.

[0024] The base plate 30 is formed by pressing a metal material such as aluminum. The base plate 30 has a bottom plate 31 on which the battery module 10 is placed and a water jacket plate 32 provided below the bottom plate 31, and is composed of two plates overlapping in the vertical direction. Between the bottom plate 31 and the water jacket plate 32, a water jacket 33 is formed in which a refrigerant (e.g., cooling water) flows to cool the battery module 10 (see FIG. 7, etc.).

[0025] A heat insulating material 34 made of, for example, foamed polypropylene is attached from below to the base plate 30, covering the water jacket 33 from below. A lower cover 35 is attached to the base plate 30 from below the heat insulating material 34.

[0026] The frame member 40 is joined to the outer edge of the base plate 30 and constitutes the outer frame (i.e., the rear wall, the front wall, the left wall, and the right wall) of the battery case 20. The frame member 40 is, for example, an aluminum casting. The frame member 40 is provided with fastening parts that are fastened to the vehicle body by bolts or the like.

[0027] The frame member 40 has a rear cross member 41 provided on the rear edge of the base plate 30, a front cross member 42 provided on the front edge of the base plate 30, and a pair of side frames 43, 44 provided on the left and right edges of the base plate 30. The rear cross member 41 and the front cross member 42 extend in the left-right direction, and the pair of side frames 43, 44 extend in the front-rear direction. The rear cross member 41 and the front cross member 42 are connected to the pair of side frames 43, 44 by welding or the like.

[0028] The rear cross member 41, the front cross member 42, and the pair of side frames 43, 44 are joined to the outer edge of the base plate 30 by, for example, friction stir welding or welding, to form the lower part of the battery case 20, i.e., the battery tray 21, as shown in Figure 5. The four battery modules 10 are placed on the battery tray 21.

[0029] The frame member 40 further includes a central cross member 45 that is provided in the center of the base plate 30 in the front-rear direction and extends in the left-right direction. The central cross member 45 is disposed between the two battery modules 10 disposed on the front side and the two battery modules 10 disposed on the rear side. The central cross member 45 is connected to a pair of side frames 43, 44 by welding or the like.

[0030] As shown in Fig. 6, the battery case 20 includes a first fixing portion 60 and a second fixing portion 70 that fix the battery module 10 to the frame member 40. In Fig. 6, the first fixing portion 60 is illustrated as a dashed circle, and the second fixing portion 70 is illustrated as a solid circle. In this embodiment, the first fixing portion 60 and the second fixing portion 70 are provided on the rear cross member 41, the front cross member 42, and the central cross member 45.

[0031] The first fixing portion 60 is provided at a position overlapping with the intermediate plate 12 when viewed from the rear. The first fixing portion 60 of the battery case 20 fixes the first fixing portion 156 of the cover plate 15 to the rear cross member 41, the front cross member 42, and the central cross member 45.

[0032] The second fixing portion 70 is provided at a position overlapping with the battery cell 11 when viewed from the rear. The second fixing portion 70 of the battery case 20 fixes the second fixing portion 158 of the cover plate 15 to the rear cross member 41, the front cross member 42, and the central cross member 45.

[0033] After the four battery modules 10 are fixed to the battery tray 21, the cover 50 is attached to the frame member 40 from above via a seal member (not shown). The cover 50 is attached to the frame member 40 by, for example, bolts or the like.

[0034] (First fixed part and second fixed part) Next, the first fixing portion 60 and the second fixing portion 70 of the battery case 20 will be described in detail with reference to Figures 7 to 13. Below, the first fixing portion 60 and the second fixing portion 70 provided on the rear cross member 41 will be described, but since the first fixing portion 60 and the second fixing portion 70 provided on the front cross member 42 and the central cross member 45 have the same configuration, their description will be omitted.

[0035] First, the specific configuration of the rear cross member 41 will be described. As shown in FIG. 7, the rear cross member 41 includes a joint 410, an inner vertical wall 411, an upper wall 412, and an outer vertical wall 413. The joint 410 is a portion that is joined to the upper surface of the base plate 30. The rear cross member 41 and the base plate 30 are joined by, for example, friction stir welding or welding. The inner vertical wall 411 stands upright from the joint 410 and is located inside the battery case 20. The upper wall 412 extends from an upper end of the inner vertical wall 411 toward the outside of the battery case 20. The upper wall 412 abuts against the opposing surface of the cover 50 when the cover 50 is attached. The outer vertical wall 413 is provided on the outside of the battery case 20 and extends downward from the upper wall 412. The inner vertical wall portion 411, the upper wall portion 412, and the outer vertical wall portion 413 form a shape in which a cross section taken along a plane perpendicular to the longitudinal direction (left-right direction) of the rear cross member 41 is open downward.

[0036] The rear end 301 of the base plate 30 is disposed below the rear cross member 41. The outer vertical wall portion 413 of the rear cross member 41 is located outboard of the rear end 301 of the base plate 30, and extends in the up-down direction so as to overlap with the rear end 301 of the base plate 30 when viewed from the rear. In other words, the lower end 414 of the outer vertical wall portion 413 is located below the rear end 301 of the base plate 30. Note that, although the rear end 301 of the base plate 30 and the outer vertical wall portion 413 are spaced apart from each other in this embodiment, they may be in contact with each other.

[0037] Next, the specific configurations of the first fixed portion 60 and the second fixed portion 70 will be described. Fig. 8 is a cross-sectional view taken along line AA in Fig. 6, and Fig. 9 is a perspective view of the first fixing part 60. The first fixing part 60 is constituted by a first fixing bracket 61 extending from the rear cross member 41 towards the battery module 10.

[0038] The first fixing bracket 61 has a connecting portion 62 that connects to the rear cross member 41, and a fastening portion 63 that is fastened to the first fixing portion 156 of the cover plate 15 by a bolt B1. The fastening portion 63 is a bolt hole. In addition, the upper portion of the first fixing bracket 61 has, between the connecting portion 62 and the fastening portion 63, an inclined portion 64 that inclines downward from the connecting portion 62 toward the inside of the battery case 20, and a horizontal portion 65 that extends horizontally from the lower end of the inclined portion 64 to the fastening portion 63.

[0039] Fig. 10 is a cross-sectional view taken along line BB in Fig. 6, and Fig. 11 is a perspective view of the second fixing portion 70. The second fixing portion 70 is formed by a second fixing bracket 71 extending from the rear cross member 41 toward the battery module 10.

[0040] The second fixing bracket 71 has a connecting portion 72 that connects to the rear cross member 41, and a fastening portion 73 that is fastened to the second fixing portion 158 of the cover plate 15 by a bolt B2. The fastening portion 73 is a bolt hole. In addition, the upper portion of the second fixing bracket 71 is approximately horizontal from the connecting portion 72 to the fastening portion 73.

[0041] The first fixing bracket 61 and the second fixing bracket 71 are provided integrally with the rear cross member 41. This makes it possible to reduce the number of parts compared to a case in which the first fixing bracket 61 and the second fixing bracket 71 are provided separately from the rear cross member 41.

[0042] Next, the transmission of a load from the first fixing portion 60 and the second fixing portion 70 to the battery module 10 when a collision load is input from behind the battery pack 1 will be described.

[0043] As shown in Figs. 12 and 13, the rear end 301 of the base plate 30 is disposed below the rear cross member 41 when viewed from the cross section. Furthermore, the outer vertical wall portion 413 of the rear cross member 41 is located outside the rear end 301 of the base plate 30 and extends in the vertical direction so as to overlap the rear end 301 of the base plate 30 when viewed from the rear. With this configuration, when a collision load is input to the battery pack 1 from the rear of the vehicle due to a collision of the vehicle V, the outer vertical wall portion 413 collides with the rear end 301 of the base plate 30, and a force T (hereinafter also referred to as a rotational force T) that rotates inwardly of the battery pack 1 around the rear end 301 of the base plate 30 as the center of rotation is applied to the rear cross member 41. This rotational force T is transmitted to the battery module 10 via the first fixing portion 60 and the second fixing portion 70.

[0044] As described above, when viewed from the rear, the first fixing portion 60 is provided at a position overlapping with the intermediate plate 12, and the second fixing portion 70 is provided at a position overlapping with the battery cell 11. When the above-mentioned rotational force T is transmitted to the battery module 10 via the first fixing portion 60 and the second fixing portion 70, it is desirable that a large amount of the rotational force T is transmitted to the intermediate plate 12, which has a large load-bearing capacity, in order to protect the battery cell 11.

[0045] In this embodiment, the first fixing part 60 is configured so that the load transmission force to the battery module 10 is greater than the load transmission force of the second fixing part 70. The load transmission force means the ability to receive the rotational force T of the rear cross member 41 and transmit the rotational force T to the battery module 10. In other words, the load transmitted from the first fixing part 60 to the battery module 10 is greater than the load transmitted from the second fixing part 70 to the battery module 10.

[0046] Moreover, the first fixing part 60 is configured to have a load capacity greater than that of the second fixing part 70 so that the load applied to the first fixing part 60 is reliably transmitted to the intermediate plate 12. Since the first fixing part 60 is disposed overlapping the intermediate plate 12, which has a large load capacity when viewed from the rear, most of the rotational force T applied to the rear cross member 41 due to a collision can be transmitted from the first fixing part 60 to the intermediate plate 12. Therefore, the battery module 10 can be appropriately protected.

[0047] Specifically, the first fixing part 60 and the second fixing part 70 are respectively constituted by a first fixing bracket 61 and a second fixing bracket 71, and the height of the connecting part 62 of the first fixing bracket 61 is higher than the height of the connecting part 72 of the second fixing bracket 71 in the up-down direction. With this configuration, the load transmission force of the first fixing part 60 can be made greater than the load transmission force of the second fixing part 70. In other words, the first fixing part 60 can receive more rotational force T of the rear cross member 41 than the second fixing part 70, and can transmit the rotational force T from the first fixing part 60 to the battery module 10.

[0048] Furthermore, an upper portion of the first fixing bracket 61 has an inclined portion 64 that inclines downward from a connecting portion 62 with the rear cross member 41 toward the inside of the battery case 20. The inclination direction of the inclined portion 64 approximately coincides with the direction in which the rotational force T is applied to the rear cross member 41. This makes it possible to prevent stress from concentrating on a portion of the first fixing bracket 61, compared to, for example, a case in which the inclined portion 64 is not provided and a step portion extending vertically is provided between the connecting portion 62 and the fastening portion 63. This makes it possible to increase the load capacity of the first fixing bracket 61.

[0049] On the other hand, the upper part of the second fixing bracket 71 is approximately horizontal from the connecting part 72 with the rear cross member 41 to the fastening part 73. The connecting part 72 of the second fixing bracket 71 is lower in height than the connecting part 62 of the first fixing bracket 61, and the upper part of the second fixing bracket 71 is approximately horizontal, so that the second fixing bracket 71 transmits a smaller load force to the battery module 10 than the first fixing bracket 61. In other words, the rotational force T of the rear cross member 41 transmitted from the second fixing bracket 71 to the battery module 10 is small, so that the battery cells 11 arranged overlapping the second fixing bracket 71 when viewed from the rear are protected.

[0050] Moreover, the first fixed bracket 61 is formed to be thicker than the second fixed bracket 71. More specifically, the first fixed bracket 61 and the second fixed bracket 71 have hollowed-out portions between the connecting portions 62, 72 and the fastening portions 63, 73, and in this region, the first fixed bracket 61 is formed to be thicker than the second fixed bracket 71. With this configuration, the load-bearing capacity of the first fixed bracket 61 can be made greater than that of the second fixed bracket 71. Furthermore, since the connection area between the first fixed bracket 61 and the rear cross member 41 is increased at the connecting portion 62, the load transmission force of the first fixed bracket 61 can be made greater.

[0051] Furthermore, the diameter of the bolt B1 fastening the fastening portion 63 of the first fixing bracket 61 to the first fixing portion 156 of the cover plate 15 is larger than the diameter of the bolt B2 fastening the fastening portion 73 of the second fixing bracket 71 to the second fixing portion 158 of the cover plate 15. In other words, the diameter of the bolt hole of the fastening portion 63 of the first fixing bracket 61 is larger than the diameter of the bolt hole of the fastening portion 73 of the second fixing bracket 71. With this configuration, the first fixing bracket 61 is firmly fixed to the first fixing portion 156 of the cover plate 15. Therefore, the load capacity of the first fixing bracket 61 can be increased, and a large load can be transmitted to the intermediate plate 12.

[0052] Variation 1 14 is a top view of the battery pack 1 of the modified example 1. In the following, common members to the above-described embodiment will be described using the same reference numerals.

[0053] In the first modification, the four battery modules 10 are arranged with the battery cells 11 stacked in the vehicle front-rear direction. A central frame 46 extending in the front-rear direction is provided between the two battery modules 10 arranged on the left side and the two battery modules 10 arranged on the right side. The first fixing portion 60 and the second fixing portion 70 are provided on the pair of side frames 43, 44 and the central frame 46.

[0054] In the first modification, the first fixing portion 60 is disposed at a position overlapping with the intermediate plate 12 having a large load resistance when viewed from the vehicle width direction, and therefore a large load can be transmitted to the intermediate plate 12. Therefore, even when a collision load is input from the side of the vehicle V, a large portion of the rotational force T of the pair of side frames 43, 44 in the inward direction of the battery case 20 can be transmitted to the intermediate plate 12, and the battery module 10 can be protected.

[0055] Variation 2 15 is a top view of the battery pack 1 of the modified example 2. In the following, common members to the above-described embodiment will be described using the same reference numerals.

[0056] In the second modification, the battery cells 11 of each battery module 10A are rectangular cells. Each battery module 10A includes a pair of end plates 13A at both ends in the stacking direction of the rectangular battery cells 11. The pair of end plates 13A are members with a large load-bearing capacity and are an example of the load-bearing member of the present invention.

[0057] In the second modification, the first fixing portions 60 provided on the rear cross member 41, the front cross member 42, and the central cross member 45 are provided at positions overlapping the pair of end plates 13A when viewed from the rear. The second fixing portions 70 are provided at positions overlapping the battery cells 11 when viewed from the rear.

[0058] In the second modification, the first fixing portion 60 is also disposed at a position overlapping the pair of end plates 13A with a large load capacity when viewed from the rear, and therefore a large load can be transmitted to the pair of end plates 13A. Therefore, even when a collision load is input from the side of the vehicle V, a large amount of the rotational force T of the frame member 40 in the inward direction of the battery case 20 can be transmitted to the pair of end plates 13A, and the battery module 10A can be protected.

[0059] Although an embodiment of the present invention and modifications have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. Furthermore, the components in the above embodiment may be arbitrarily combined within the scope of the invention.

[0060] For example, in the embodiment described above, the first fixing portion 60 of the battery case 20 fixes the first fixing portion 156 of the cover plate 15 of the battery module 10 to the frame member 40 at a position overlapping with the intermediate plate 12 when viewed from behind, but this is not limited to this. For example, the first fixing portion 60 may directly fix the intermediate plate 12 to the frame member 40.

[0061] Also, for example, in the embodiment described above, the upper part of the first fixing bracket 61 has the inclined portion 64, but this is not limited thereto, and the first fixing bracket 61 may not have the inclined portion 64. Since the height of the connecting portion 62 of the first fixing bracket 61 is higher than the height of the connecting portion 72 of the second fixing bracket 71, the load transmission force of the first fixing bracket 61 can be increased even without providing the inclined portion 64, and the battery module 10 can be protected.

[0062] This specification describes at least the following items. In parentheses, components corresponding to the above-described embodiment are shown as examples, but the present invention is not limited to these.

[0063] (1) A battery module (battery module 10, 10A) having a plurality of battery cells (battery cells 11) stacked in a first direction among horizontal directions and load-bearing members (an intermediate plate 12, a pair of end plates 13A) extending in a second direction among the horizontal directions perpendicular to the first direction; A battery pack (battery pack 1) equipped with a battery case (battery case 20) that houses the battery module and is mounted on a vehicle (vehicle V), The battery case includes: A base plate (base plate 30) on which the battery module is mounted; A frame member (frame member 40) that is joined to an outer edge portion of the base plate and that constitutes an outer frame of the battery case; a first fixing portion (first fixing portion 60) provided on the frame member at a position overlapping with the load-bearing member when viewed from the second direction, and fixing a first portion (first fixing portion 156, an intermediate plate 12, and a pair of end plates 13A) of the battery module to the frame member; a second fixing portion (second fixing portion 70) that is provided on the frame member at a position different from a position overlapping with the load-bearing member when viewed from the second direction and fixes a second portion (second fixing portion 158) of the battery module to the frame member; The base plate has a tip (rear end 301) of the outer edge portion as viewed in cross section disposed below the frame member, The frame member has a vertical wall portion (outer vertical wall portion 413) that is located outside the tip of the base plate and extends in the up-down direction so as to overlap the tip of the base plate when viewed from the second direction, the first fixing portion is configured such that, when a load in the second direction is applied to the first fixing portion and the second fixing portion, a load transmission force to the battery module is greater than a load transmission force of the second fixing portion, and a load capacity is greater than a load capacity of the second fixing portion. Battery pack.

[0064] According to (1), when a load is input to the battery pack from the second direction due to a vehicle collision or the like, a force is applied to the frame member to rotate inwardly of the battery pack around the tip of the base plate as the center of rotation. The first fixing part has a larger load transmission force and load resistance than the second fixing part, and therefore receives more of the rotational force of the frame member than the second fixing part. The first fixing part is provided at a position overlapping with the load-bearing member when viewed from the second direction, and therefore most of the rotational force applied to the frame member can be transmitted from the first fixing part to the load-bearing member. Thus, the battery module can be protected against the load input to the frame member.

[0065] (2) A battery pack according to (1), the first fixing portion and the second fixing portion are respectively constituted by a first fixing bracket (first fixing bracket 61) and a second fixing bracket (second fixing bracket 71) extending from the frame member toward the battery module, In the vertical direction, the height of a connecting portion (connecting portion 62) between the first fixing bracket and the frame member is higher than the height of a connecting portion (connecting portion 72) between the second fixing bracket and the frame member. Battery pack.

[0066] According to (2), the load transmission force of the first fixed portion can be made greater than the load transmission force of the second fixed portion.

[0067] (3) A battery pack according to (2), the first fixing bracket has a first fastening portion (fastening portion 63) fastened to the first portion of the battery module, The upper portion of the first fixing bracket has an inclined portion (inclined portion 64) between the connecting portion with the frame member and the first fastening portion, the inclined portion inclining downward from the connecting portion toward the inside of the battery case, Battery pack.

[0068] According to (3), it is possible to prevent stress from concentrating on one part of the first fixing bracket, and it is possible to increase the load resistance of the first fixing bracket.

[0069] (4) A battery pack according to (2) or (3), the second fixing bracket has a second fastening portion (fastening portion 73) fastened to the second portion of the battery module, The upper portion of the second fixing bracket is substantially horizontal from the connection portion with the frame member to the second fastening portion. Battery pack.

[0070] According to (4), the connecting portion of the second fixing bracket is lower in height than the connecting portion of the first fixing bracket, and the upper portion of the second fixing bracket is substantially horizontal, so that the load transmission force from the second fixing portion to the battery module can be made smaller than the load transmission force of the first fixing portion, thereby protecting the battery module.

[0071] (5) A battery pack according to any one of (2) to (4), The first fixing bracket is thicker than the second fixing bracket. Battery pack.

[0072] According to (5), the load capacity of the first fixing bracket can be made larger than that of the second fixing bracket.

[0073] (6) A battery pack according to any one of (1) to (5), the first fixing portion has a first fastening portion (fastening portion 63) fastened to the first portion of the battery module by a first bolt (bolt B1); the second fixing portion has a second fastening portion (fastening portion 73) fastened to the second portion of the battery module by a second bolt (bolt B2); The diameter of the first bolt is larger than the diameter of the second bolt. Battery pack.

[0074] According to (6), the first fixing part and the first portion of the battery module are firmly fixed to each other, so that the first fixing part can bear a large load.

[0075] (7) A battery pack according to any one of (1) to (6), The first fixing portion and the second fixing portion are integrally provided on the frame member. Battery pack.

[0076] According to (7), the number of parts can be reduced. [Explanation of symbols]

[0077] 1 Battery pack 10, 10A Battery Module 11 Battery Cell 12 Intermediate plate (load-bearing member, first part) 13A Pair of end plates (load-bearing members) 156 First fixed part (first part) 158 Second fixed part (second part) 20 Battery case 30 Base Plate 40 Frame members 413 Outer vertical wall (vertical wall) 60 1st fixed part 61 First fixing bracket 62 Connecting part 63 Fastening part (1st fastening part) 64 Slope 70 Second fixed part 71 Second fixing bracket 72 Connecting part 73 Fastening part (second fastening part) B1 Bolt (First Bolt) B2 Bolt (Second bolt) V Vehicle

Claims

1. a battery module including a plurality of battery cells stacked in a first direction among horizontal directions and a load-bearing member extending in a second direction among the horizontal directions perpendicular to the first direction; A battery pack to be mounted on a vehicle, comprising: a battery case that houses the battery module; The battery case includes: A base plate on which the battery module is mounted; A frame member joined to an outer edge portion of the base plate and constituting an outer frame of the battery case; a first fixing portion provided on the frame member at a position overlapping with the load-bearing member when viewed from the second direction, the first fixing portion fixing a first portion of the battery module to the frame member; a second fixing portion provided on the frame member at a position different from a position overlapping with the load-bearing member when viewed from the second direction, the second fixing portion fixing a second portion of the battery module to the frame member; a tip of the outer edge portion of the base plate as viewed in cross section is disposed below the frame member, the frame member has a vertical wall portion that is located outside the tip of the base plate and extends in a vertical direction so as to overlap the tip of the base plate when viewed from the second direction, the first fixing portion is configured such that, when a load in the second direction is applied to the first fixing portion and the second fixing portion, a load transmission force to the battery module is greater than a load transmission force of the second fixing portion, and a load capacity is greater than a load capacity of the second fixing portion. Battery pack.

2. 2. The battery pack according to claim 1, the first fixing portion and the second fixing portion are respectively constituted by a first fixing bracket and a second fixing bracket extending from the frame member toward the battery module, In the vertical direction, a height of a connection portion between the first fixing bracket and the frame member is higher than a height of a connection portion between the second fixing bracket and the frame member. Battery pack.

3. 3. The battery pack according to claim 2, the first fixing bracket has a first fastening portion fastened to the first portion of the battery module, An upper portion of the first fixing bracket has an inclined portion between the connecting portion with the frame member and the first fastening portion, the inclined portion inclining downward from the connecting portion toward the inside of the battery case, Battery pack.

4. 4. The battery pack according to claim 2, the second fixing bracket has a second fastening portion fastened to the second portion of the battery module, The upper portion of the second fixing bracket is substantially horizontal from the connection portion with the frame member to the second fastening portion. Battery pack.

5. 4. The battery pack according to claim 2, The first fixing bracket is thicker than the second fixing bracket. Battery pack.

6. 4. The battery pack according to claim 1, the first fixing portion has a first fastening portion fastened to the first portion of the battery module by a first bolt, the second fixing portion has a second fastening portion fastened to the second portion of the battery module by a second bolt, The diameter of the first bolt is larger than the diameter of the second bolt. Battery pack.

7. 4. The battery pack according to claim 1, The first fixing portion and the second fixing portion are integrally provided on the frame member. Battery pack.

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