Battery-equipped structure

Abstract

Reduces damage to the battery pack (battery cells) during a collision. [Solution] The present invention comprises a pair of side frames 41, a pair of cross frames 42, a battery case 21, and a battery cell module 22 having a flange portion 22a. The pair of side frames are connected to the side members 14 of the vehicle, the battery case is fastened to the pair of cross frames and is spaced apart from the pair of side frames, the battery case is located inside and has a support portion 24a at the flange portion for the battery cell module.

Description

Technical Field

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

Background Art

[0002] An electric vehicle equipped with an electric motor as a driving power source requires a large and high-capacity battery as the power source of the electric motor. Such a battery may be mounted under the floor. Regarding the technology related to such a battery, there is disclosed a structure in which a battery pack is connected to a pair of skeleton members on both sides of the vehicle and a pair of cross members arranged in front and rear of the battery pack via connecting portions connected to battery modules to ensure the rigidity of the vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the battery pack is coupled to the skeleton members on both sides of the vehicle via the connecting portions, the battery pack cannot move in the vehicle width direction during a side collision, and there is a risk that the battery pack may be damaged by the intrusion of an object that is the source of the collision.

[0005] An object of the present invention is to reduce damage to battery cells included in the battery pack during a collision.

Means for Solving the Problems

[0006] One aspect of the present invention is a battery mounting structure having a pair of side frames, a pair of cross frames, a battery case, and battery cells. The pair of side frames are arranged on the left and right sides below the floor panel that constitutes the floor surface of the vehicle compartment and form a pair. The pair of cross frames are configured to connect the pair of side frames. The battery case is arranged between the pair of side frames and between the pair of cross frames. The battery cells are arranged inside the battery case and have flange portions that protrude outward in the vehicle width direction and extend in the vehicle longitudinal direction. The pair of side frames are fastened to the vehicle's frame members. The battery case is fastened to the pair of cross frames and is spaced apart from the pair of side frames. The battery case has support portions provided inside that support the battery modules at the flange portions.

[0007] According to the above vehicle structure, damage to the battery cells in the battery pack during a collision can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram schematically shows the bottom surface of the vehicle according to the embodiment. [Figure 2] This is an exploded view showing the fastening of the battery case and the cross frame according to the embodiment. [Figure 3] This is a schematic diagram showing the fastening of the battery case to the cross frame and the positional relationship with objects located around the lower perimeter according to the embodiment. [Figure 4] This is a schematic cross-sectional view that passes through the inside of the battery case and follows the width of the vehicle. [Figure 5] This is a schematic diagram illustrating the deformation of the battery or battery case during a side collision. [Figure 6] Following Figure 5, this is a schematic diagram showing the deformation of the battery or battery case during a side impact. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. The embodiments shown herein are illustrative examples for embodying the technical idea of ​​the present invention and do not limit the present invention. Therefore, all other implementable forms, examples, and operational techniques that can be conceived by those skilled in the art without departing from the spirit of the present invention are included in the scope and spirit of the present invention, as well as in the claims and their equivalents.

[0010] Furthermore, the drawings attached to this specification may be schematically represented with changes to scale, aspect ratio, shape, etc., from the actual object for the sake of illustration and ease of understanding, but these are merely examples and do not limit the interpretation of the present invention.

[0011] In this specification, ordinal numbers such as "the first," "the second," etc., may be used. However, unless otherwise specified, these ordinal numbers are used for the convenience of explanation to identify the constituent elements and do not specify a number or order.

[0012] In each figure, arrows denoted by X, Y, and Z indicate the orientation of the components constituting the vehicle structure according to the embodiment. X represents the longitudinal direction of the vehicle and is denoted as longitudinal direction X. Y represents the width direction of the vehicle and is denoted as vehicle width direction Y. Z represents the height direction of the vehicle and is denoted as height direction Z.

[0013] Figure 1 is a schematic diagram showing the bottom surface of the vehicle 10. Figure 2 is an exploded view showing the fastening of the battery case 21 and the cross frame 42 according to the embodiment. Figure 3 is a schematic diagram showing the fastening of the battery case 21 and the cross frame 42 according to the embodiment and the positional relationship with objects located around the lower perimeter. Figure 4 is a schematic cross-sectional view passing through the inside of the battery case 21 and along the vehicle width direction Y. Figure 5 is a schematic diagram showing the deformation of the battery 20 or battery case 21 during a side collision. Figure 6 is a schematic diagram showing the deformation of the battery 20 or battery case 21 during a side collision, following Figure 5.

[0014] As shown in Figure 1, the vehicle 10 of the embodiment has an internal combustion engine 11 and a drive motor 12. The vehicle 10 has a floor panel 13, a pair of side members 14 (corresponding to structural members), and a battery 20. The floor panel 13 constitutes the floor surface of the passenger compartment. The pair of side members 14 are located on the left and right sides below the floor panel 13. The side members 14 constitute part of the frame of the vehicle 10's substructure. The side members 14 are the most rigid parts of the vehicle structure. The battery 20 is located between the pair of side members 14 below the floor panel 13. The battery 20 supplies power to the drive motor 12.

[0015] The internal combustion engine 11 has an exhaust pipe 15 through which exhaust gases flow, extending toward the rear of the vehicle. A portion of the exhaust pipe 15 extends in the space between the battery 20 and one side member 14. A first heat pipe 31 and a second heat pipe 32 are positioned along the exhaust pipe 15, intersecting it longitudinally and having a larger cross-sectional area than other parts. The first heat pipe 31 is positioned between the battery 20 and one side member 14 in the vehicle width direction Y.

[0016] Furthermore, the internal combustion engine 11 is not limited to being used as a power source. The internal combustion engine 11 can be used as a power source for power generation. The first heat pipe 31 and the second heat pipe 32 may include a filter section and a catalyst section. The second heat pipe 32 is not necessarily required, and the first heat pipe 31 alone may suffice.

[0017] As shown in Figure 4, the battery 20 includes a battery case 21 and a battery cell module 22 housed within the battery case 21. The battery case 21 includes a bottom plate 23, four side wall portions 24 fixed to the bottom plate 23, and a cover portion 25 that closes the upper end openings of the side wall portions 24. The four side wall portions 24 include two side wall portions 24 located in the vehicle width direction Y and two side wall portions 24 located in the longitudinal direction X. The side wall portions 24 located in the longitudinal direction X have flange portions 24b (corresponding to the case flange portion) that protrude outward in the longitudinal direction X. The flange portions 24b are not at the same height as the lower surface of the bottom plate portion 23, but are located higher than the bottom plate portion 23 in the height direction Z. The flange portions 24b are attached to a subframe 40, which will be described later, as shown in Figures 2 and 3. The constituent materials of the battery case 21 are not particularly limited. The bottom plate portion 23 can be made of, for example, a solid plate material. The side wall portion 24 can be made of a hollow body partitioned into multiple compartments by solid plates or ribs. The cover portion 25 can be made of solid plates.

[0018] As shown in Figure 2, the vehicle 10 further has a subframe 40. The subframe 40 has a pair of side frames 41 arranged on the left and right sides below the floor panel 13 that constitutes the floor surface of the passenger compartment, and a pair of front and rear cross frames 42 that connect the pair of side frames 41. The side frames 41 are connected to the side members 14. The side frames 41 and cross frames 42 are configured in an elongated shape, and the cross sections that intersect in the longitudinal direction are formed into an open U-shaped cross section. The lower surface of the cross frame 42 is located below the lower surface of the side member 14, at approximately the same height as the lower surface of the side frame 41, and below the lower surface of the bottom plate portion 23 of the battery case 21. The battery case 21 is arranged between the pair of side frames 41 and the pair of cross frames 42. The battery cell module 22 is arranged inside the battery case 21 and has a flange portion 22a that protrudes outward in the vehicle width direction Y and extends in the front and rear direction X. The battery case 21 is fastened only to a pair of cross frames 42 by bolts and nuts at the flange portion 24b, which is the mounting portion, and is not fastened to a pair of side frames 41, and is configured to be spaced apart in the vehicle width direction Y. The pair of side frames 41 are configured to be fastened to the side members 14 (the vehicle may be a frame type or a monocoque type). The battery case 21 has support portions 24a on the side wall portion 24 which are provided inside and support the battery cell modules 22 at the flange portion 22a. Multiple support portions 24a are provided vertically (two in this embodiment) so that the battery cell modules 22 can be housed in multiple vertical layers inside the battery case 21.

[0019] When there is an input from a collision object S in the vehicle width direction Y, the battery case 21 is not coupled to the side frame 41, so as shown in FIGS. 5 and 6, the battery case 21 moves in accordance with the deformation of the cross frame 42, thereby reducing interference with the collision object S. Further, the flange portion 22a provided on the battery cell module 22 protrudes outward in the vehicle width direction Y and is configured to extend in the front-rear direction X. Therefore, when a collision object S collides from the side, the flange portion 22a hits the collision object S first, thereby preventing a direct hit on the main body of the battery cell module 22 inside the battery case 21.

[0020] In addition, on the outer surface of the battery case 21, a flange portion 24b is provided which is spaced upward from the bottom surface and is fastened to the pair of cross frames 42. Thereby, the capacity of the battery cell module 22 accommodated inside the battery case 21 can be increased compared to the case where the flange portion 24b is at the same height as the bottom plate portion 23.

[0021] In addition, the bottom plate portion 23 of the battery case 21 is configured not to protrude below the lower ends of the pair of side frames 41 and the pair of cross frames 42. Therefore, when the vehicle approaches a road surface protrusion T (see FIG. 4) due to unevenness of the road surface during traveling, interference with the battery case 21 can be prevented by contacting the cross frame 42 or the side frame 41. If the cross frame 42 and the side frame 41 are located below the lower end of the battery case 21, the positional relationship between the cross frame 42 and the side frame 41 does not have to be the same as in FIG. 3. That is, either one of the side frame 41 and the cross frame 42 may be arranged above the other.

[0022] Furthermore, the battery case 21 is configured to have a first heat pipe 31 extending in the front-rear direction X on its side in the vehicle width direction Y. The flange portion 24b of the battery cell module 22 is provided to protrude outward in the vehicle width direction Y, as described above. This allows for a distance between the first heat pipe 31 and the battery cell module 22, thereby reducing the heat transferred from the first heat pipe 31 to the battery cell module 22.

[0023] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. In the above description, the cross-sectional shape of the side frame 41 and the cross frame 42 is described as an open U-shaped cross section where the cross sections intersect in the longitudinal direction. However, the cross-sectional shape is not limited to this, and may also be solid or a hollow closed cross section such as an O shape. Furthermore, the cross-sectional shapes of the side frame 41 and the cross frame 42 may be different from each other. [Explanation of Symbols]

[0024] 13 floor panels, 14 side members, 21 Battery Case, 22 Battery cell modules (battery cells), 22a Flange section, 24a support part, 24b Flange section (case flange section), 31 1st heat piping (heat piping), 41 Side frame, 42 Cross frame, X front and rear direction, Y in the vehicle width direction, Z is the height direction.

Claims

1. A pair of side frames are positioned on the left and right sides of the underside of the floor panel that makes up the floor surface of the passenger compartment, A pair of front and rear cross frames connecting the pair of side frames, A battery case positioned between the pair of side frames and between the pair of cross frames, The battery cell is located inside the battery case and has a flange portion that protrudes outward in the vehicle width direction and extends in the vehicle's longitudinal direction, The pair of side frames are connected to the vehicle's structural members. The aforementioned battery case is Fastened to the aforementioned pair of cross frames, The pair of side frames are spaced apart from the aforementioned pair of side frames. The battery mounting structure comprises a battery case provided inside, with a support portion that supports the battery cell at the flange portion.

2. The battery mounting structure according to claim 1, wherein the battery case is provided on the outer surface of the battery case, spaced above the bottom surface, and includes a case flange portion that is fastened to the pair of cross frames.

3. The battery mounting structure according to claim 1 or claim 2, wherein the bottom surface of the battery case is located above the lower ends of the pair of side frames and the pair of cross frames.

4. The battery mounting structure according to claim 3, wherein a heat pipe extending in the longitudinal direction of the vehicle is arranged on the side of the battery case in the vehicle width direction.

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