Battery pack

Abstract

The utility model provides a battery pack which not only can enable external input to be difficult to transmit to a battery unit, but also can improve the inherent value of the battery pack. A battery pack includes a plurality of battery modules, a pack case, and a plurality of brackets. The plurality of battery modules are arranged side by side in the column direction. The battery pack case is attached to a vehicle body and accommodates a plurality of battery modules. The plurality of brackets fix the plurality of battery modules to the pack case. The column direction is a direction orthogonal to the longitudinal direction of each of the plurality of battery modules. Each of the plurality of battery modules includes a fixing portion provided at a position corresponding to an end portion in both the longitudinal direction and the column direction. The plurality of brackets are fixed to the fixing parts of the plurality of battery modules.

Description

Technical Field

[0001] The utility model relates to a battery pack mounted on a vehicle. Background Art

[0002] Japanese Patent Laid-Open Publication No. 2020-196434 discloses a battery unit mounting structure for suppressing the up-and-down resonance between a vehicle body and a battery unit in an electric vehicle. The battery unit includes: a battery module; a pair of left and right side frames having mounting portions relative to a pair of bottom frames and extending in the front-rear direction; a battery tray supported by at least the pair of side frames and forming the bottom of the battery unit; and a plurality of cross frames connecting between the pair of side frames. On this basis, the battery module is mounted on the cross frame and vertically displaced relative to the battery tray so as to separate the vertical movement of the battery tray supported by the side frames from the vertical movement of the battery module, making the so-called battery module movement more directional.

[0003] In a vehicle equipped with a battery pack, improving the natural frequency of the battery pack is related to the improvement of the riding comfort performance of the vehicle. To improve the above natural frequency, an effective method is to rigidly and continuously connect the battery module housed in the battery pack housing to the battery pack housing. However, doing so will easily transmit the external input to the vehicle body to the battery cells inside the battery module. Summary of the Utility Model

[0004] The present utility model is completed in view of the above problems, and the object of the present utility model is to provide a battery pack that can make it difficult for external input to be transmitted to the battery cells while improving the natural frequency of the battery pack.

[0005] The battery pack of the present utility model includes a plurality of battery modules, a battery pack housing, and a plurality of brackets. The plurality of battery modules are arranged and configured along the column direction. The battery pack housing is mounted on the vehicle body and houses the plurality of battery modules. The plurality of brackets fix the plurality of battery modules to the battery pack housing. The column direction is a direction orthogonal to the respective length directions of the plurality of battery modules. The plurality of battery modules each include fixing portions provided at positions corresponding to both ends of the length direction and the column direction. The plurality of brackets are fixed to the fixing portions of the plurality of battery modules.

[0006] According to the content of the present utility model, the bracket for fixing the battery module to the battery pack housing is fixed to the fixing portion provided at a position corresponding to both ends of the length direction and the column direction in the battery module. By having such a structure, it is possible to improve the natural frequency of the battery pack while making it difficult for external input to be transmitted to the battery cells.

[0007] In the above battery pack, the plurality of battery modules include a first battery module and a second battery module adjacent to each other in the column direction, and at least one of the plurality of brackets is formed to be fixed to both the fixing portion of the first battery module and the fixing portion of the second battery module.

[0008] In the above battery pack, the battery pack case includes a cross beam extending in the longitudinal direction, and the cross beam is located in the space between two battery modules adjacent to each other in the column direction among a plurality of battery modules, and is a member of a frame structure body forming the frame of the battery pack case. Description of the Drawings

[0009] Figure 1 It is a schematic structural diagram of a battery pack according to an embodiment.

[0010] Figure 2 For explaining the structure related to the Figure 1 shown bracket, it is a perspective view. Detailed Description of the Invention

[0011] Figure 1 It is a schematic structural diagram of a battery pack 1 according to an embodiment. Figure 1 The direction of "FR" shown is equivalent to the front direction of the vehicle on which the battery pack 1 is mounted. The direction of "RH" is equivalent to the right direction of the vehicle. Figure 1 It shows the internal structure of the battery pack 1 when viewed from above the vehicle ( Figure 2 the direction of "UPR" shown).

[0012] The battery pack 1 includes a plurality of battery modules 10 and a battery pack case 20. The plurality of battery modules 10 each have a substantially rectangular parallelepiped shape and include a plurality of battery cells stacked along the length direction D2 described later. The battery pack case 20 includes a lower case 21 and an upper case, and houses the plurality of battery modules 10. In Figure 1 and the following Figure 2 , the illustration of the upper case is omitted. The battery pack case 20 is mounted on the vehicle body 100. For example, the battery pack case 20 includes a connecting portion 22 mounted on the lower case 21. As an example, the lower case 21 is mounted on the vehicle body 100 via the connecting portion 22 under the floor of the vehicle.

[0013] Inside the battery pack case 20, the plurality of battery modules 10 are arranged and disposed along the column direction D1. As Figure 1 shown, when viewing the battery pack 1 from above, the column direction D1 is a direction orthogonal to the respective length directions D2 of the plurality of battery modules 10. In addition, in this example, in each column of the battery modules 10, two battery modules 10 are disposed in a state of being connected along the length direction D2. Further, in this example, the column direction D1 is parallel to the vehicle front-rear direction, and the length direction D2 is parallel to the vehicle left-right direction (vehicle width direction).

[0014] The battery pack housing 20 includes side reinforcements 23 and cross beams 24, which are components of a framework structure that forms the framework of the battery pack housing 20 (lower housing 21). The side reinforcements 23 and cross beams 24 are mounted on the main body 25 of the lower housing 21 so as to surround a plurality of battery modules 10. More specifically, as Figure 1 shown, the side reinforcements 23 are respectively disposed outside the ends of the battery modules 10 in the longitudinal direction D2 (vehicle width direction) and extend along the column direction D1 (vehicle front-rear direction). In addition, the cross beams 24 are respectively disposed in the spaces between two battery modules 10 adjacent to each other in the column direction D1 and extend along the longitudinal direction D2. And both ends of each cross beam 24 are respectively connected to two side reinforcements 23. The battery pack housing 20 has a structure in which the loads acting on the battery pack housing 20 from the outside are dispersed by the side reinforcements 23 and cross beams 24 formed in this way.

[0015] In addition, the battery pack 1 has a plurality of brackets 30 for fixing the plurality of battery modules 10 to the battery pack housing 20. The following will refer to Figure 2 and Figure 1 to describe the configuration related to the brackets 30. Figure 2 is a perspective view for explaining the configuration related to the brackets 30 as shown in Figure 1 . Figure 2 is Figure 1 an enlarged view of the portion indicated by symbol A in

[0016] As Figure 1 shown, the plurality of battery modules 10 respectively have fixing portions 11 that are combined with the brackets 30. The brackets 30 are fixed to the fixing portions 11, for example, by fastening with fasteners 31 such as bolts (refer to Figure 2 ). In addition, in Figure 1 , the brackets 30 are only shown exemplarily at one place, but brackets 30 are also provided in the same way for other fixing portions 11.

[0017] The fixing portions 11 are provided at positions corresponding to the ends of the battery modules 10 in both the longitudinal direction D2 and the column direction D1. In the examples shown in Figure 1 and Figure 2 , two fixing portions 11 are provided for one end of one battery module 10. More specifically, as an example, the two fixing portions 11 are formed on a component 13 that is separated from the housing main body 12 of the battery module 10 and is mounted on the housing main body 12. In addition, one battery module 10 may also have only one fixing portion.

[0018] More specifically, in Figure 1 and Figure 2In the example shown, when looking at two battery modules (first and second battery modules) 10 adjacent to each other in the column direction D1, the bracket 30 is formed to be fixed to both the fixing portions 11 of the first battery module 10 and the fixing portions 11 of the second battery module 10 (except for the brackets fixed to the fixing portions 11 at the ends of the battery pack 1 in the column direction D1). In other words, the bracket 30 is formed to straddle the first and second battery modules 10. More specifically, each bracket 30 is fixed to the fixing portion 11 of the two fixing portions 11 of the first battery module 10 that is closer to the second battery module 10. Similarly, each bracket 30 is fixed to the fixing portion 11 of the two fixing portions 11 of the second battery module 10 that is closer to the first battery module 10.

[0019] In addition, regarding each bracket 30 on the lower housing 21 side, in Figure 1 and Figure 2 In one example shown, each bracket 30 is fixed to the side reinforcement 23 of the lower housing 21. This fixing can also be performed by tightening a fastener 32 such as a bolt.

[0020] In a vehicle equipped with a battery pack, an increase in the natural value of the battery pack is related to an improvement in the ride comfort performance of the vehicle (more specifically, for example, a reduction in the floor vibration level based on the mass effect). To increase this natural value, an effective method is to rigidly and continuously connect (fix) the battery modules (high-rigidity components) housed in the battery pack housing to the battery pack housing. Specifically, it is effective to continuously (integrally) fix the ends in the length direction D2 of the battery modules along the column direction D1. In addition, as also adopted in the example of the battery pack 1 shown in Figure 1 fixing the battery module 10 to the side reinforcement 23 by the bracket 30 can also effectively increase the fixing value, and the side reinforcement 23 is one of the members of the frame structure that constitutes the skeleton of the lower housing 21.

[0021] However, if the above structure for increasing the fixing value is adopted, it is easier to transmit the input from the outside to the vehicle body to the battery cells inside the battery module. More specifically, in Figure 1 In the example shown, the input from the left-right direction of the vehicle to the vehicle body 100 (input during a side collision) is more likely to be transmitted to the battery cells inside the battery module 10 through the bracket 30.

[0022] In view of the above problems, in the battery pack 1 of the present embodiment, the fixing portions 11 for fixing each battery module 10 to the battery pack housing 20 (lower housing 21) by the bracket 30 are provided at positions corresponding to the ends of the battery module 10 in both the length direction D2 and the column direction D1. In other words, in the battery pack 1, at the ends in the length direction D2 of each battery module 10, at positions other than the ends in the column direction D1 (that is, in Figure 2The weak part B (i.e., the central part of the ventral surface of the battery module 10) of the battery module 10 shaded by diagonal lines is not provided with a fixing part 11 for fixing the bracket 30. Thus, as Figure 2 shown by the arrow C in the figure, this enables an external input to be transmitted to the structural components (such as the side wall 12a of the housing main body 12) of the battery module 10 through the fastening points of the bracket 30. Therefore, the internal components of the battery module 10, such as battery cells and connection components, can be protected. It is worth mentioning that the weak part B mentioned here refers to the part far from the structural components of the battery module 10. Therefore, when an external input acts on this part, the input may more easily act on the internal components such as battery cells.

[0023] As described above, according to the battery pack 1 of the present embodiment, it is possible to make it difficult for an external input to be transmitted to the battery cells and to improve the inherent value of the battery pack 1.

[0024] In addition, in the present embodiment, the plurality of brackets 30 are respectively formed to be fixed to both the fixing part 11 of one of the two battery modules 10 adjacent to each other in the column direction D1, that is, the first battery module 10, and the fixing part 11 of the other, that is, the second battery module 10. Thus, compared with a comparative example in which the respective fixing parts 11 of the first and second battery modules 10 are set in pairs for the brackets 30 respectively, it is possible to efficiently set the brackets 30 while reducing the number of components and the assembly man-hours. In addition, compared with the above comparative example, depending on the action mode of the external input, it is also possible to expect the effect of well dispersing the external input to the two battery modules 10.

[0025] In addition, in the present embodiment, the battery pack housing 20 (lower housing 21) includes a cross beam 24 extending along the length direction D2, and the cross beam 24 is located in the space between the two battery modules 10 adjacent to each other in the column direction D1. By arranging the cross beam 24 between the battery modules 10, it is possible to effectively reduce the input transmitted from the outside to each fixing part 11 through the bracket 30 by using the cross beam 24.

Claims

1. A battery pack, characterized in that: have: A plurality of battery modules are arranged in a column direction; a battery pack housing mounted on the vehicle body and accommodating the plurality of battery modules; and a plurality of brackets for fixing the plurality of battery modules to the battery pack housing; The row direction is a direction orthogonal to the length direction of each of the plurality of battery modules. Each of the plurality of battery modules includes a fixing portion provided at a position corresponding to an end portion in both the longitudinal direction and the row direction. The plurality of brackets are fixed to the fixing portions of the plurality of battery modules.

2. The battery pack according to claim 1, characterized in that: The plurality of battery modules include a first battery module and a second battery module adjacent to each other in the column direction, At least one of the plurality of brackets is formed to be fixed to both the fixing portion of the first battery module and the fixing portion of the second battery module.

3. The battery pack according to claim 1 or 2, characterized in that: The battery pack case includes a crossbeam extending in the length direction, the crossbeam being located in a space between two of the battery modules adjacent to each other in the column direction as a member of a skeleton structure forming a skeleton of the battery pack case.

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