Vehicle battery support structure

Abstract

A vehicle battery support structure 20 is provided with: a frame 21 demarcating a battery retention space A1 in which a plurality of battery modules 30 are retained; a cross member 22 partitioning the battery retention space A1 into a plurality of module retention areas A2 in which each of the plurality of battery modules 30 is retained; a plurality of thin plate-like members 23 provided under the battery retention space A1; and a vehicle body fastening member 24 provided between a vehicle body 10 of a vehicle 1 and the frame 21. The frame 21 is attached to the vehicle body 10 of the vehicle 1 via the vehicle body fastening member 24, and the plurality of thin plate-like members 23 are fastened to the frame 21 and disposed so as not to be positioned under the cross member 22.

Description

Vehicle battery support structure

[0001] The present invention relates to a vehicle battery support structure.

[0002] In the battery pack support structure described in Patent Document 1, an outer frame, which is a plate-like member provided at the bottom of the battery pack, is attached directly to the vehicle body.

[0003] Japanese Patent Application Laid-Open No. 2019-166905

[0004] However, in the battery pack support structure described in Patent Document 1, vibrations of the battery pack are easily transmitted to the vehicle body via the plate-like member.

[0005] The problem to be solved by the present invention is to provide a vehicle battery support structure that suppresses vibrations transmitted from a battery module to a vehicle body.

[0006] The present invention solves the above problem by attaching a frame that defines the battery storage space to the vehicle body via a body fastening member, and by positioning a reinforcing plate provided at the bottom of the battery storage space so that it is fastened to the frame and not located below the cross member that divides the battery storage space into multiple module storage areas.

[0007] According to the present invention, it is possible to suppress vibrations transmitted from the battery module to the vehicle body.

[0008] Fig. 1 is a perspective view showing a state in which a vehicle battery support structure according to the present embodiment is attached to a vehicle body. Fig. 2 is a plan view of the vehicle battery support structure shown in Fig. 1. Fig. 3 is a cross-sectional view of the vehicle battery support structure shown in Fig. 2 taken along line III-III. Fig. 4 is a cross-sectional view of the reinforcing plate (elongated plate-shaped member) of the vehicle battery support structure shown in Fig. 2 taken along line IV-IV.

[0009] As shown in Fig. 1, the vehicle battery support structure 20 is provided on the bottom side of the body 10 of the vehicle 1. The vehicle battery support structure 20 is disposed between a pair of side sills 11 provided on the body 10. In Fig. 1, a bottom plate 20a is attached to the bottom side of the vehicle battery support structure 20. Furthermore, four elongated plate-like members 23 are provided inside the vehicle battery support structure 20, extending in the left-right direction X1 of the vehicle body 10 and aligned in the front-rear direction X2 of the vehicle body 10. The vehicle battery support structure 20 supports a plurality of battery modules 30.

[0010] FIG. 2 is a plan view showing the internal structure of the vehicle battery support structure 20 with the bottom plate 20a removed. The left side of FIG. 2 corresponds to the front side (FR) of the vehicle 1, and the right side corresponds to the rear side (RE). As shown in FIG. 2 , the vehicle battery support structure 20 includes a frame 21 that defines a battery storage space A1 in which multiple battery modules 30 are stored. The battery storage space A1 inside the frame 21 includes a first region B1 having a generally trapezoidal shape whose width gradually narrows toward the rear side (RE), and a second region B2 having a generally rectangular shape on the front side (FR) of the first region B1. The frame 21 may be a component integrally formed by extrusion molding, or may be a component formed by welding multiple members together. As shown in FIG. 3 , a top plate 26 is attached to the upper end of the frame 21. A cooling plate 25 is attached to the lower end of the frame 21. That is, the battery storage space A1 is a space surrounded by the frame 21, the top plate 26, and the cooling plate 25.

[0011] As shown in FIG. 2 , the vehicle battery support structure 20 has ten cross members 22. Each of the cross members 22 is welded to the inside of the frame 21. Five cross members 22 are attached to the right side of the frame 21 at predetermined intervals, extending in the left-right direction X1. Similarly, five cross members 22 are attached to the left side of the frame 21 at predetermined intervals, extending in the left-right direction X1. The spaces between the cross members 22 aligned in the front-rear direction X2 form module storage areas A2. In the example shown in FIG. 2 , eight module storage areas A2 are formed in the second area B2 of the battery storage space A1. That is, the cross members 22 divide the battery storage space A1 into multiple module storage areas A2.

[0012] As shown in Fig. 2 , three battery modules 30 are housed in the first region B1 of the battery housing space A1. Furthermore, eight battery modules 30 are housed in each module housing region A2 in the second region B2 of the battery housing space A1. That is, the vehicle battery support structure 20 has eleven battery modules 30. Furthermore, each battery module 30 has a plurality of cells 31. In the example shown in Fig. 2 , the stacking direction LY of the cells 31 is the left-right direction X1.

[0013] Four elongated and narrow plate members 23 constituting a reinforcing plate are provided at the bottom of the frame 21. The elongated and narrow plate members 23 are provided at the bottom of the battery storage space A1. Each elongated and narrow plate member 23 is arranged to cross the battery storage space A1 in the left-right direction X1. That is, each elongated and narrow plate member 23 extends in the stacking direction LY of the cells 31 of the battery module 30. Each elongated and narrow plate member 23 is arranged so as not to be located below the cross member 22. Each elongated and narrow plate member 23 is arranged so that its central axis L is located below the center of the module storage area A2. The number of elongated and narrow plate members 23 constituting the reinforcing plate is not limited to the present embodiment. The reinforcing plate is not limited to a plurality of elongated and narrow plate members 23. For example, it may be a single rectangular plate member covering the bottom of the battery storage space A1.

[0014] 3, each end 23a of the elongated plate-like member 23 is fastened to the frame 21 by a connecting member 27 such as a bolt. The position of the connecting member 27, i.e., the fastening position between the frame 21 and the elongated plate-like member 23, is located on the central axis L of the elongated plate-like member 23.

[0015] As shown in the cross-sectional view of FIG. 4 , the elongated plate-like member 23 has a bottom surface portion 23b, a pair of inclined portions 23c, and a pair of upper surface portions 23d. Specifically, the bottom surface portion 23b is a flat plate-like portion. A pair of inclined portions 23c is connected to each of both ends of the bottom surface portion 23b in the front-rear direction X2. The pair of inclined portions 23c are inclined so that the distance between them gradually increases upward. A pair of upper surface portions 23d, which are flat plate-like portions, is connected to the upper ends of each of the pair of inclined portions 23c. The bottom surface portion 23b of the elongated plate-like member 23 contacts the bottom plate 20a (see FIG. 1 ). The upper surface portion 23d of the elongated plate-like member 23 contacts the cooling plate 25 (see FIG. 3 ). Due to the cross-sectional shape described above, each elongated plate-like member 23 has elasticity in the vertical direction.

[0016] As shown in FIG. 3 , a cooling plate 25 for cooling the battery module 30 is provided between the frame 21 and the elongated plate-like member 23. The elongated plate-like member 23 and the cooling plate 25 are made of different materials. For example, the elongated plate-like member 23 is made of 6000-series aluminum, and the cooling plate 25 is made of 3000-series aluminum. The thicknesses of the elongated plate-like member 23 and the cooling plate 25 are different. For example, the thickness of the elongated plate-like member 23 is 1 to 2 mm, and the thickness of the cooling plate 25 is 3 to 4 mm. More preferably, the thickness of the elongated plate-like member 23 is 2 mm, and the thickness of the cooling plate 25 is 3 mm.

[0017] Furthermore, vehicle body fastening members 24 are provided between the side sill 11 of the vehicle body 10 and the frame 21. The frame 21 is attached to the side sill 11 via the vehicle body fastening members 24. As shown in FIG. 2 , the elongated plate-like members 23 are positioned so that the central axes L of the elongated plate-like members 23 are not positioned below fastening positions C between the frame 21 and the vehicle body fastening members 24. In other words, in the fore-and-aft direction X2, the fastening positions C between the frame 21 and the vehicle body fastening members 24 and the central axes L of the elongated plate-like members 23 are alternately positioned. The frame 21 and the vehicle body fastening members 24 are fastened together with bolts or the like.

[0018] As described above, in the vehicle battery support structure 100 according to this embodiment, the frame 21 is attached to the vehicle body 10 of the vehicle 1 via the vehicle body fastening members 24. Furthermore, the reinforcing plate (the elongated plate-like member 23) provided in the lower portion of the battery storage space A1 is fastened to the frame 21 and positioned so as not to be located below the cross member 22. This allows the vehicle battery support structure 100 to suppress vibrations transmitted from the battery modules 30 to the vehicle body 10. By attaching the frame 21 to the vehicle body 10 via the vehicle body fastening members 24, vibrations generated in the battery modules 30 are less likely to be transmitted to the vehicle body 10 than when the frame 21 is directly attached to the vehicle body 10. Furthermore, because the frame 21, which is the framework of the vehicle battery support structure 100, has high rigidity, fastening the reinforcing plate (the elongated plate-like member 23) to the frame 21, which is a highly rigid portion, reduces the vibrations of the battery modules 30 from being transmitted to the vehicle body 10. Furthermore, if the reinforcing plate (elongated plate-like member 23) is located below the cross member 22, the position of the reinforcing plate will be shifted from the position corresponding to the battery module 30, thereby reducing the effect of the reinforcing plate in suppressing vibration of the battery module 30. Therefore, by positioning the reinforcing plate (elongated plate-like member 23) so that it is not located below the cross member 22, the effect of suppressing vibration of the battery module 30 can be enhanced. Therefore, the vehicle battery support structure 100 has a structure that makes it difficult for vibration of the battery module 30 to be transmitted to the vehicle body 10.

[0019] Furthermore, in the vehicle battery support structure 100, the reinforcing plate is a plurality of elongated plate-like members 23, and both ends of each of the plurality of elongated plate-like members 23 are fastened to the frame 21. As a result, by fastening both ends of each of the elongated plate-like members 23 to the frame 21, which is a high-rigidity portion, vibrations of the battery module 30 are less likely to be transmitted to the vehicle body 10. Furthermore, since the reinforcing plate is made up of a plurality of elongated plate-like members 23, an effect of reducing the weight of the vehicle battery support structure 100 is obtained.

[0020] Furthermore, in the vehicle battery support structure 100, the central axis L of the elongated plate member 23 is located below the center position of the module storage area A2. This allows the elongated plate member 23 to efficiently suppress vibration of the battery module 30.

[0021] Furthermore, in the vehicle battery support structure 100, the battery module 30 has a plurality of cells 31 stacked in a predetermined stacking direction LY, and the elongated plate-like members 23 extend in the stacking direction LY. Here, vibration of the battery module 30 occurs due to misalignment between the cells 31. Therefore, by arranging the elongated plate-like members 23 to extend along the stacking direction LY, misalignment between the cells 31 is suppressed, and vibration of the battery module 30 is suppressed.

[0022] Furthermore, in the vehicle battery support structure 100, the elongated plate-like members 23 are positioned so that the central axes L of the elongated plate-like members 23 are not located below the fastening positions C between the frame 21 and the vehicle body fastening members 24. This prevents vibrations of the battery modules 30 transmitted to the elongated plate-like members 23 from being transmitted to the vehicle body 10 via the fastening positions C between the frame 21 and the vehicle body fastening members 24.

[0023] Furthermore, in the vehicle battery support structure 100, a cooling plate 25 for cooling the battery module 30 is provided between the frame 21 and the reinforcing plate (the elongated plate-like member 23), which further suppresses vibrations transmitted from the reinforcing plate to the frame 21.

[0024] Furthermore, in the vehicle battery support structure 100, the material of the reinforcing plate (the elongated plate-like member 23) is different from the material of the cooling plate 25. This causes a difference in the resonance frequency between the reinforcing plate and the cooling plate 25, reducing the probability of resonance occurring and suppressing the amplitude of vibration of the vehicle battery support structure 100.

[0025] Furthermore, in the vehicle battery support structure 100, the plate thickness of the reinforcing plate (the elongated plate-like member 23) is different from the plate thickness of the cooling plate 25. This causes a difference in the resonance frequency between the reinforcing plate and the cooling plate 25, reducing the probability of resonance occurring and suppressing the amplitude of vibration of the vehicle battery support structure 100.

[0026] Furthermore, in the vehicle battery support structure 100, the frame 21 is attached to the side sill 11 of the vehicle body 10 via vehicle body fastening members 24. As a result, the vehicle battery support structure 100 is attached to the side sill 11, which is a highly rigid part of the vehicle body 10, and therefore vibrations transmitted to the vehicle body 10 are suppressed.

[0027] Furthermore, in the vehicle battery support structure 100, the reinforcing plate (the elongated plate-like member 23) has elasticity, which makes it more difficult for vibrations of the battery module 30 to be transmitted to the vehicle body 10.

[0028] REFERENCE SIGNS LIST 1 vehicle 10 vehicle body 11 side sill 20 vehicle battery support structure 21 frame 22 cross member 23 elongated plate-shaped member (reinforcement plate) 24 vehicle body fastening member 15 cooling plate 30 battery module 31 cell A1 battery storage space A2 module storage area

Claims

1. A vehicle battery support structure that supports a plurality of battery modules installed in a vehicle, comprising: a frame that defines a battery storage space in which the plurality of battery modules are stored; a cross member that divides the battery storage space into a plurality of module storage areas in which each of the plurality of battery modules is stored; a reinforcing plate provided at the bottom of the battery storage space; and a vehicle body fastening member provided between the body of the vehicle and the frame, wherein the frame is attached to the body of the vehicle via the vehicle body fastening member, and the reinforcing plate is fastened to the frame and positioned so as not to be located under the cross member.

2. The vehicle battery support structure according to claim 1, wherein the reinforcing plate is a plurality of elongated plate members, both ends of each of the plurality of elongated plate members being fastened to the frame.

3. The vehicle battery support structure according to claim 2, wherein the central axis of said elongated plate member is located below the central position of said module storage area.

4. A vehicle battery support structure as claimed in claim 2 or 3, wherein the battery module has a plurality of cells stacked in a predetermined stacking direction, and the elongated plate-like members extend in the stacking direction.

5. A vehicle battery support structure as described in any one of claims 2 to 4, wherein the elongated plate member is positioned so that the central axis of the elongated plate member is not located under the fastening position between the frame and the vehicle body fastening member.

6. A vehicle battery support structure as claimed in any one of claims 1 to 5, wherein a cooling plate for cooling the battery module is provided between the frame and the reinforcing plate.

7. The vehicle battery support structure according to claim 6, wherein the material of the reinforcing plate and the material of the cooling plate are different from each other.

8. A vehicle battery support structure as set forth in claim 6 or 7, wherein the thickness of said reinforcing plate and the thickness of said cooling plate are different from each other.

9. A vehicle battery support structure according to any one of claims 1 to 8, wherein the frame is attached to a side sill of the vehicle body via the vehicle body fastening member.

10. A vehicle battery support structure according to any one of claims 1 to 9, wherein the reinforcing plate has elasticity.

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