Battery pack

Abstract

The present invention provides a battery pack capable of improving the inherent value of the battery pack while making it difficult for external input to be transmitted to a battery cell. 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 present invention relates to a battery pack mounted on a vehicle. Background Art

[0002] Japanese Patent Publication No. 2020-196434 discloses a battery cell mounting structure for suppressing resonance between a vehicle body and a battery cell in an electric vehicle in the up-and-down direction. The battery cell has: a battery module; a pair of left and right side frames, which have mounting portions relative to a pair of bottom frames and extend front and rear; a battery tray, which is supported by at least one pair of side frames and forms the bottom of the battery cell; and a plurality of cross frames, which connect the pair of side frames. On this basis, the battery module is mounted on the cross frame and is vertically displaced relative to the battery tray so as to separate the vertical movement of the battery tray supported by the side frame from the vertical movement of the battery module, i.e., the so-called battery module movement is more directional.

[0003] In a vehicle equipped with a battery pack, improving the inherent value of the battery pack is related to improving the ride comfort performance of the vehicle. In order to improve the above inherent value, an effective way is to rigidly and continuously connect the battery module contained in the battery pack housing to the battery pack housing. However, doing so makes it easier for external input to the vehicle body to be transmitted to the battery cells in the battery module. Summary of the invention

[0004] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a battery pack that can make it difficult for external input to be transmitted to a battery cell and improve the inherent value of the battery pack.

[0005] The battery pack of the present invention comprises a plurality of battery modules, a battery pack housing and a plurality of brackets. The plurality of battery modules are arranged in a row direction. The battery pack housing is mounted on a vehicle body and accommodates the plurality of battery modules. The plurality of brackets fix the plurality of battery modules to the battery pack housing. The row direction is a direction orthogonal to the respective length directions of the plurality of battery modules. The plurality of battery modules respectively include a fixing portion disposed at a position corresponding to the end of both the length direction and the row direction. The plurality of brackets are fixed to the fixing portions of the plurality of battery modules.

[0006] According to the present invention, a bracket for fixing a battery module to a battery pack housing is fixed to a fixing portion provided at a position corresponding to both the end of the battery module in the length direction and the end of the row direction. By having such a structure, it is possible to improve the inherent value of the battery pack while making it difficult for external input to be transmitted to the battery cell.

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

[0008] In the above battery pack, the pack case includes a beam extending in the length direction, the beam being a member of a skeleton structure forming a skeleton of the pack case and located in a space between two battery modules adjacent to each other in the column direction among the plurality of battery modules. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0010] Figure 2 For illustration and Figure 1 A three-dimensional view of the structure related to the bracket shown. DETAILED DESCRIPTION

[0011] Figure 1 FIG. 1 is a schematic structural diagram of a battery pack 1 according to an embodiment. Figure 1 The direction of "FR" shown corresponds to the front direction of the vehicle on which the battery pack 1 is mounted. The direction of "RH" corresponds to the right direction of the vehicle. Figure 1 Indicates the direction from the top of the vehicle ( Figure 2 The internal structure of the battery pack 1 when viewed from above (in 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 a length direction D2 described later. The battery pack case 20 includes a lower case 21 and an upper case, and accommodates the plurality of battery modules 10. Figure 1 and the following Figure 2 In the figure, 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 housing 20, a plurality of battery modules 10 are arranged along a column direction D1. Figure 1 As shown, when the battery pack 1 is viewed from above, the column direction D1 is a direction orthogonal to the longitudinal direction D2 of each 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 arranged in a state of being connected along the longitudinal direction D2. Furthermore, in this example, the column direction D1 is parallel to the front-rear direction of the vehicle, and the longitudinal direction D2 is parallel to the left-right direction of the vehicle (the vehicle width direction).

[0014] The battery pack housing 20 includes side reinforcements 23 and cross beams 24 as components of a skeleton structure forming the skeleton of the battery pack housing 20 (lower housing 21). The side reinforcements 23 and cross beams 24 are mounted to the main body 25 of the lower housing 21 in such a manner as to surround the plurality of battery modules 10. In more detail, Figure 1 As shown, the side reinforcements 23 are respectively arranged on the outer sides of each end of the battery module 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 arranged in the space between two battery modules 10 adjacent to each other in the column direction D1 and extend along the longitudinal direction D2. In addition, both ends of each cross beam 24 are connected to two side reinforcements 23 respectively. The battery pack housing 20 has a structure that uses the side reinforcements 23 and cross beams 24 formed in this way to disperse the load acting on the battery pack housing 20 from the outside.

[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 case 20. Figure 2 and Figure 1 The structure related to the bracket 30 will be described. Figure 2 For illustration and Figure 1 A perspective view of the structure related to the bracket 30 is shown. Figure 2 yes Figure 1 An enlarged view of the portion indicated by symbol A.

[0016] like Figure 1 As shown, each of the plurality of battery modules 10 has a fixing portion 11 coupled to a bracket 30. The bracket 30 is secured to the battery module 10 by a fastener 31 such as a bolt (see FIG. Figure 2 ) is fastened to the fixing portion 11. Figure 1 In the figure, the bracket 30 is shown only at one place as an example, but the bracket 30 is also provided for the other fixing parts 11.

[0017] The fixing portion 11 is provided at a position corresponding to the end of the battery module 10 in both the longitudinal direction D2 and the column direction D1. Figure 1 and Figure 2 In the example shown, 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 separate from the case body 12 of the battery module 10 and is mounted on the case body 12. In addition, one battery module 10 may have only one fixing portion.

[0018] More specifically, in Figure 1 and Figure 2In the example shown, when focusing on 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 portion 11 of the first battery module 10 and the fixing portion 11 of the second battery module 10 (except for the bracket fixed to the fixing portion 11 located at the end of the battery pack 1 in the column direction D1). In other words, the bracket 30 is formed so as 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, which 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, which is closer to the first battery module 10.

[0019] In addition, regarding each bracket 30 on the lower case 21 side, Figure 1 and Figure 2 In the example shown, each bracket 30 is fixed to the side reinforcement 23 of the lower case 21. This fixation may also be performed by fastening with a fastener 32 such as a bolt.

[0020] In a vehicle equipped with a battery pack, improving the inherent value of the battery pack is related to improving the ride comfort performance of the vehicle (more specifically, for example, reducing the floor vibration level based on the mass effect). In order to improve this inherent value, an effective method is to rigidly and continuously connect (fix) the battery module (high-rigidity component) housed in the battery pack housing to the battery pack housing. Specifically, it is effective to continuously (integrally) fix the end of the battery module in the length direction D2 along the column direction D1. In addition, as Figure 1 As also adopted in the example of the battery pack 1 shown, fixing the battery module 10 to the side reinforcement 23 which is one of the components of the skeleton structure constituting the skeleton of the lower case 21 by means of the bracket 30 can also effectively improve the fixing value.

[0021] However, if the above-mentioned structure for increasing the fixed value is adopted, it is easier to transmit the input from the outside to the vehicle body to the battery cells in the battery module. Figure 1 In the illustrated example, input from the left-right direction of the vehicle to the vehicle body 100 (input during a side collision) is more easily transmitted to the battery cells in the battery module 10 via the bracket 30 .

[0022] In view of the above problems, in the battery pack 1 of the present embodiment, the fixing portion 11 for fixing each battery module 10 to the battery pack case 20 (lower case 21) via the bracket 30 is provided at a position corresponding to the end 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 end of each battery module 10 in the length direction D2, at a position other than the end in the column direction D1 (i.e., at the end of each battery module 10 in the length direction D2, at a position other than the end in the column direction D1 (i.e., at the end of each battery module 10 in the length direction D2). Figure 2The weak point B of the battery module 10 (i.e., the center of the ventral surface of the battery module 10) is not provided with the fixing portion 11 for fixing the bracket 30. Figure 2 As shown by the arrow C in the middle, this allows the external input to be transmitted to the structural components of the battery module 10 (such as the side wall 12a of the housing body 12) through the fastening point of the bracket 30. Therefore, it is possible to protect the internal components of the battery module 10 such as the battery cells and connecting components. It is worth mentioning that the weak point B mentioned here refers to a part away from the structural components of the above-mentioned battery module 10, so when the external input acts on this part, the input may be more likely to act on the internal components such as the battery cells.

[0023] As described above, according to the battery pack 1 of the present embodiment, it is possible to make it difficult for 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 portion 11 of the first battery module 10 and the fixing portion 11 of the second battery module 10, which are one of the two battery modules 10 adjacent to each other in the column direction D1. Thus, compared with the comparative example in which the brackets 30 are respectively set to the respective fixing portions 11 of the first and second battery modules 10 in pairs, the brackets 30 can be set efficiently while reducing the number of parts and the number of assembly man-hours. In addition, compared with the above comparative example, according to the mode of action of the external input, the effect of distributing the external input well to the two battery modules 10 can also be expected.

[0025] In addition, in the present embodiment, the battery pack case 20 (lower case 21) includes a beam 24 extending along the length direction D2, and the beam 24 is located in the space between two battery modules 10 adjacent to each other in the row direction D1. By arranging the beam 24 between the battery modules 10, the input transmitted from the outside to each fixing portion 11 through the bracket 30 can be effectively reduced by the 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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