Battery pack

Abstract

The utility model relates to a battery pack. The battery pack includes a battery fastening member, a front-rear structural member, a plurality of left-right structural members, and a load transmission member disposed near at least one side of the case and fixed across the front-rear structural member and the left-right structural members. When the battery module is disposed between two adjacent left-right structural members among the plurality of left-right structural members, i.e., the inner side in the front-rear direction, the battery module is fixed to the case by means of the connection portion and the fastening connection portion. At least a portion of an end portion of the load transmission member on the front-rear structural member side is disposed further inward in the front-rear direction than the fastening portion.

Description

Technical Field

[0001] This disclosure relates to battery packs. Background Technology

[0002] In recent years, battery packs have been used in battery electric vehicles and other similar applications. Considering the potential for external impacts on the battery pack, impact-absorbing materials are employed. Japanese Patent Application Publication No. 2013-062092 discloses an external cushioning material that can be manufactured at low cost and protects the battery pack from impacts. Utility Model Content

[0003] When an impact is applied to the battery pack from the outside due to a vehicle collision, especially when the load enters the side of the battery pack, the load may sometimes be applied to the battery modules housed inside. Therefore, there is a desire to improve the protection capability of the housed battery modules even in the event of an impact from the outside of the vehicle, in order to achieve further safety.

[0004] This disclosure was made in view of the above-mentioned problems, and provides a battery pack that improves the protection capability of the housed battery module.

[0005] The battery pack disclosed herein features:

[0006] A battery fastening connection component has a fastening connection part, which uses a connecting part to fix a battery module with a connecting part to a housing.

[0007] A front-to-back structural member, wherein the front-to-back structural member is disposed near the side of the housing and extends in the front-to-back direction;

[0008] A plurality of left-right directional structural members, the ends of which abut against front-back directional structural members, and the plurality of left-right directional structural members are orthogonally arranged to the front-back directional structural members and extend along the left-right direction; and

[0009] A load-transferring member is disposed near at least one side of the housing and is fixed throughout the front-rear structural members and the left-right structural members.

[0010] When the battery module is positioned between two adjacent left-right structural members (i.e., on the inner side of the front-rear direction) and fixed to the housing using connecting and fastening parts,

[0011] At least a portion of the end of the load transfer member on the front-rear direction structural member side is positioned inside the fastening connection in the front-rear direction.

[0012] Therefore, when a load is applied to the battery pack, the load can be guided via the load transfer member in a way that does not apply a large load to the battery module.

[0013] According to this disclosure, a battery pack with improved protection for the housed battery module can be provided. Attached Figure Description

[0014] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals denote like elements, and in the drawings:

[0015] Figure 1 This is a top view of the battery pack disclosed herein;

[0016] Figure 2 This is an enlarged top view of the main parts of the battery pack disclosed herein;

[0017] Figure 3 This is an enlarged top view of the main parts of the battery pack disclosed herein;

[0018] Figure 4 This is an enlarged perspective view of the main parts of the battery pack disclosed herein;

[0019] Figure 5 This is an enlarged perspective view of the main parts of the battery pack disclosed herein;

[0020] Figure 6A This is an enlarged top view of the main parts of the battery pack disclosed herein;

[0021] Figure 6B This is an enlarged top view of the main parts of the battery pack disclosed herein. Detailed Implementation

[0022] Implementation Method 1

[0023] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments. In addition, for the sake of clarity, the following description and drawings are appropriately simplified.

[0024] Hereinafter, the battery pack of this embodiment will be described with reference to the accompanying drawings. Figure 1 This is a top view of the battery pack disclosed herein. Figure 2 It is Figure 1 An enlarged top view of the main part of the battery pack, enclosed by a single-dotted line.

[0025] Here, Figure 1 as well as Figure 2The left-hand direction is set as the forward direction (Fr direction) of the battery pack 10 when it is mounted in a vehicle. Figure 1 as well as Figure 2 The upward direction is defined as the right direction (RH direction) of the battery pack 10 when it is mounted in a vehicle.

[0026] like Figure 1 as well as Figure 2 As shown, the battery pack 10 includes a housing 1, a battery module 2, multiple left-right structural components 3, a battery fastening connection component 4, a front-rear structural component 5, and a load transfer component 6.

[0027] Hereinafter, the left-right direction of the battery pack 10 when mounted in the vehicle will sometimes be described as the side direction. Furthermore, in both the front-rear and left-right directions, the direction closer to the center of the battery pack 10 will be designated as the inner side, and the opposite direction as the outer side. For example, the direction in which the battery module 2 is disposed within the housing 1 will be designated as the inner side in the front-rear direction. Conversely, the direction in which the left-right structural members 3, arranged continuously in the front-rear direction, are disposed to sandwich the battery module 2 will be designated as the outer side in the front-rear direction.

[0028] The housing 1 houses the battery modules 2, multiple left-right structural members 3, battery fastening connecting members 4, and front-rear structural members 5. The battery pack 10 includes multiple battery modules 2, multiple left-right structural members 3, multiple battery fastening connecting members 4, multiple front-rear structural members 5, and multiple load-transfer members 6. The housing 1 has a bottom surface 1a (see reference). Figure 1 Furthermore, sometimes the left and right ends of the outer shape of the housing 1 are described as the sides of the housing 1. Additionally, the sides of the housing are referred to as side 1b.

[0029] More specifically, the left-right structural component 3, the battery fastening structural component 4, and the front-back structural component 5 are respectively disposed on the bottom surface 1a. The battery module 2 is, for example, a lithium-ion battery.

[0030] The battery module 2 is rectangular in shape, extending in both the front-back and left-right directions. The battery module 2 is disposed within the housing 1 between two adjacent left-right structural members 3, i.e., on the inner side in the front-back direction.

[0031] Furthermore, the battery module 2 has a connecting portion 2a protruding from the side in the left-right direction. The connecting portion 2a is fixed to the housing 1 via a fastening connection portion 4a of the battery fastening connector 4 (described later), thereby fixing the battery module 2 to the housing 1. Here, the connecting portion 2a is provided with a hole that extends through in the vertical direction and allows for bolt fixing.

[0032] Here, in battery module 2, two connecting portions 2a protruding to the right from the right side are respectively provided on the front and rear sides, and the same is true for the left side. That is, the connecting portions 2a of battery module 2 are formed by protruding from each corner of the rectangular battery module 2 toward the side portion 1b of the housing 1.

[0033] In addition, busbars are provided on the left and right sides of the battery module 2 to electrically connect the battery cells forming the battery module 2 to each other.

[0034] To simplify the explanation of the structure of the battery pack 10, the description will focus on the right side of the battery module 2, but the left side of the battery module 2 can also be configured in the same way.

[0035] like Figure 2 As shown, the left-right structural member 3 is an internal structural member (inner crossbeam) of the battery pack, and is arranged in a shape that has a predetermined height from the bottom surface 1a upward and extends in the left-right direction. In addition, a plurality of left-right structural members 3 are arranged continuously in the front-back direction, separated from each other by a predetermined distance at approximately equal intervals.

[0036] The front-to-back structural member 5 is an internal structural member of the battery pack and is disposed near the side 1b of the housing 1. Furthermore, the front-to-back structural member 5 is configured to have a predetermined height extending upwards from the bottom surface 1a and along the front-to-back direction. Alternatively, the front-to-back structural member 5 may be disposed in a location other than near the side 1b of the housing 1; however, in this description, it will be configured to be disposed only near the left and right sides 1b of the housing 1.

[0037] Here, multiple left-right structural members 3 are arranged such that their ends abut against the front-rear structural members 5 and the multiple left-right structural members 3 extend in an orthogonal direction, i.e., in the left-right direction, relative to the front-rear structural members 5.

[0038] The battery fastening connection member 4 is disposed between the side portion of the battery module 2 in the left-right direction and the front-back structural member 5. The battery fastening connection member 4 is provided with multiple fastening connection portions 4a, which serve as holes through which bolts can pass in the vertical direction. Furthermore, regarding the vertical position of the battery fastening connection member 4, typically, a portion of the battery fastening connection member 4 is disposed between the load transfer member 6 and the connecting portion 2a; the load transfer member 6 is disposed below the battery fastening connection member 4, and the connecting portion 2a of the battery module 2 is disposed above the battery fastening connection member 4.

[0039] For example, the battery module 2 and the battery fastening connector 4 are arranged such that the holes in the connecting portion 2a and the fastening connector 4a are aligned vertically in a straight line. The battery module 2 and the battery fastening connector 4 can be fixed together by bolting through these holes.

[0040] The load transfer member 6 is fixed to both the left-right structural member 3 and the front-back structural member 5. Therefore, the load transfer member 6 is located near the side 1b of the housing 1.

[0041] Specifically, the load transfer member 6 is configured to cover a portion of both the left-right structural member 3 and the front-back structural member 5.

[0042] Furthermore, the load transfer member 6 has a shape that extends in the front-rear direction at the portion covering the front-rear structural member 5. Specifically, at least a portion of the end of the load transfer member 6 on the front-rear structural member 5 side is formed to extend in the front-rear direction from the extension of the left-right structural member 3 in the top view toward the battery module 2 side in the front-rear direction.

[0043] The load transfer member 6 is elongated in the front-rear direction at the portion covering the front-rear structural member 5. That is, at least a portion of the portion extending in the front-rear direction at the end near the side portion in the left-right direction of the load transfer member 6 is positioned inside the front-rear direction of the fastening connection portion 4a of the battery fastening connection member 4.

[0044] Therefore, the load transfer member 6 is positioned such that at least a portion of the end of the front-rear structural member 5 is disposed between the side portion 1b of the housing 1 and the connecting portion 2a that is closest to the load transfer member 6, and is located in a position that is further inward than the connecting portion 2a in the front-rear direction.

[0045] The load transfer member 6 can be configured to extend only forward at the end of the front-rear structural member 5, or extend only backward. In this case, for the part where the left-right structural member 3 abuts against the front-rear structural member 5 at point 1, one load transfer member 6 extending forward and one load transfer member 6 extending backward can be provided.

[0046] On the other hand, the load transfer member 6 can also be a member that extends from the end of the front-rear structural member 5 in both the front-rear and rear directions.

[0047] For example, consider a battery module 2 where at least two connecting portions 2a are neatly arranged in the front-to-back direction on one side in the left-to-right direction, each with a corresponding fastening connection portion 4a of the battery fastening connecting member 4. For clarity, the fastening connection portion 4a located on the front side of the plurality of fastening connections 4a used to fix the battery module 2 near the load transfer member 6 is designated as fastening connection portion 41 (not shown), and the fastening connection portion 4a located on the rear side is designated as fastening connection portion 42. Similarly, the fastening connection portion 4a located on the front side of the plurality of fastening connections 4a used to fix the battery module 2 near the load transfer member 6 on the rear side is designated as fastening connection portion 43, and the fastening connection portion 4a located on the rear side is designated as fastening connection portion 44.

[0048] The load transfer member 6 has a shape in which the end on the front-rear structural member 5 side extends forward. In this case, at least a portion of the forward-extending portion is positioned forward of the rearmost fastening connection portion 42 in the fastening connection portion 4a, which is positioned corresponding to the connection portion 2a of the battery module 2, which is positioned near the front side of the load transfer member 6. Similarly, the load transfer member 6 has a shape in which the end on the front-rear structural member 5 side extends rearward. In this case, at least a portion of the rearward-extending portion is positioned rearward of the frontmost fastening connection portion 43 in the fastening connection portion 4a, which is positioned corresponding to the connection portion 2a of the battery module 2, which is positioned near the rear side of the load transfer member 6.

[0049] In addition, for the purpose of explanation, regarding the load transfer member 6, the load transfer member 6 having a shape that extends forward is designated as load transfer member 61, and the load transfer member 6 having a shape that extends backward is designated as load transfer member 62.

[0050] Figure 3 This is a top view showing the load transfer member 6 and the length relationship related to the configuration of the load transfer member 6, and showing the main parts of the battery pack. (See attached image.) Figure 3 As shown, multiple load transfer members 6 correspond to multiple left-right structural members 3. Each load transfer member 6 is provided with a forward-extending load transfer member (first load transfer member) 61 and a rearward-extending load transfer member (second load transfer member) 62. In adjacent left-right structural members 3, the distance from the rear end of the second load transfer member 62, which corresponds to the forward left-right structural member 3, to the front end of the first load transfer member 61, which corresponds to the rear left-right structural member 3, is shorter than the length obtained by adding the distance from the front end to the rear end of the load transfer member 61 and the distance from the front end to the rear end of the load transfer member 62.

[0051] More specifically, such as Figure 3 As shown, in the battery pack 10, the distance A between the parts of the load transfer members 6 that are separated from each other is shorter than the length obtained by adding the length B of a first load transfer member 61 and the length C of a second load transfer member 62. In this way, the shapes of the first load transfer member 61 and the second load transfer member 62 can be determined.

[0052] Furthermore, the length of the load transfer member 6 extending in the left-right direction, that is, the length of the portion of the load transfer member 6 covering the left-right structural member 3, can be arbitrarily changed. Typically, the inner end of the load transfer member 6 covering the left-right structural member 3 in the left-right direction can be set to be closer to the inner side in the left-right direction than the connection portion 2a of the battery module 2.

[0053] Furthermore, when the load transfer member 6 is fixed to the fastening connection portion 4a of the battery fastening connector 4 and the connection portion 2a of the battery module 2 using bolts, it can be fixed by the bolt passing through the hole provided in the load transfer member 6. Moreover, the method of fixing the load transfer member 6 is not limited to forming a hole and having the bolt pass through it. For example, the load transfer member 6 may not have a hole, and when the fastening connection portion 4a and the connection portion 2a are fixed using bolts, it may be fixed by pressing down from above using the battery fastening connector 4 at a position different from the fastening connection portion 4a and the connection portion 2a.

[0054] Figure 4 It is Figure 1 The image shows an enlarged 3D view of the main components of the battery pack. Additionally, Figure 5 Is with Figure 4 Similarly, a magnified 3D view of the main parts of the battery pack is shown, with arrows indicating examples of load paths that distribute the load. Furthermore, in Figure 4 and Figure 5 The illustration of battery module 2 is omitted. Here, in the load transfer member 6, a notch 6a is formed near the corner of battery module 2 and close to the battery fastening connection member 4.

[0055] By providing a notch 6a, the load transfer member 6 can be positioned so that the left-right structural member 3, the battery fastening connection member 4, and the load transfer member 6 are not joined together. That is, by providing a notch 6a in at least a portion, the load transfer member 6 forms a part that prevents contact between the load transfer member 6 and the battery fastening connection member 4. Therefore, the left-right structural member 3 and the battery fastening connection member 4 can be positioned so that they directly abut against each other at a position away from the connecting part 2a and the fastening connection part 4a.

[0056] With this configuration, when a load is applied from the side of the battery pack 10, within the battery pack 10, such as Figure 5 As shown, this achieves a state where the load path is interrupted. That is, during the transfer from the load transfer member 6 to the battery module 2, it becomes a state along... Figure 5 The dashed arrow indicates the state of the path traveled. In this path, it is difficult for force to be transmitted from the load transfer member 6 to the battery module 2, thus suppressing the input of load to the battery module 2.

[0057] In addition, an example of the relationship between the position of the applied external force and the manner in which the load is transmitted into the battery pack 10 when an external force is applied to the side 1b of the housing 1 is described with reference to the accompanying drawings. Figure 6A and Figure 6B This is a top view enlarged of the main part of the battery pack 10, and a diagram showing examples of load transfer in cases where external forces are applied due to vehicle collisions, etc., indicated by arrows.

[0058] Figure 6A This is an example of a situation where a pole violently collides with the extension of the left-right structural member 3, generating a load from the right side of the left-right structural member 3 toward the left-right inward direction. In this case, the battery pack 10 is in a state where a load is applied to the left-right structural member 3 from the position of the violent collision of the pole toward the left-right inward direction. Therefore, in the battery pack 10, it becomes difficult to apply loads to the battery module 2 and the battery fastening connection member 4.

[0059] on the other hand, Figure 6B This is an example of a load generated inward in the left-right direction at the midpoint between the continuous left-right structural members 3 in the front-rear direction, i.e., at the right side of the battery module 2. In this case, in the battery pack 10, the load flows from the position of the violent collision of the rods to the load transfer member 6, thereby distributing the load to the two left-right structural members 3 arranged in a manner that sandwiches the collision position in the front-rear direction. Therefore, in the battery pack 10, it is possible to suppress the application of large loads to the battery module 2 and the battery fastening connection member 4.

[0060] Here, the first load transfer member 61 is shaped such that the end portion of the side portion in the left-right direction extends forward. The second load transfer member 62 is shaped such that it extends rearward. Each end portion is positioned closer to the front-rear direction than the fastening connection portion 4a of the battery fastening connection member 4. In this case, regarding the bending start point of the front-rear structural member 5, compared to the case where load transfer members 61 and 62 are not provided, by providing load transfer members 61 and 62, the distance between the portions of the front-rear structural member 5 that become the bending start point is more easily brought closer together.

[0061] Therefore, load transfer members 61 and 62 are provided inside the battery pack 10. As a result, even if the front-to-back structural member 5 is bent due to an external impact, the battery fastening connection member 4 is not easily pressed inward in the left-to-right direction by the front-to-back structural member 5.

[0062] Moreover, in this case, the battery fastening connecting structure 4, which is pressed by the front-rear structural member 5, can suppress the inward pressing of the busbar disposed on the side of the battery module 2 in the left-right direction.

[0063] In addition, such as Figure 3 As shown, the lengths of the first load transfer member 61 and the second load transfer member 62 in the longitudinal direction are sufficiently long. Therefore, when a load is applied, the distance between the point of impact when an obstacle hits the outside of the battery pack 10 and the part in the longitudinal structural member 5 that acts as the starting point of bending can be brought close.

[0064] That is, in the front-to-back structural member 5, the distance between the force point and the point of application of the moment becomes shorter, thus improving the bending stiffness.

[0065] Moreover, such as Figure 4 as well as Figure 5 As shown, the load transfer member 6 is provided with a notch 6a. This allows the load transfer member 6 to be positioned such that the left-right structural member 3, the battery fastening connection member 4, and the load transfer member 6 are not connected, effectively cutting off the load path. Therefore, even when a load is applied from outside the vehicle, input to the fastening connection member 4a can be suppressed.

[0066] Based on the above description, in the battery pack 10, the load-transferring member 6, which has a shape extending in the front-rear direction near the side of the battery pack 10, is correspondingly arranged with each of the left-right structural members 3. This improves the protection performance of the battery module 2 against external loads.

[0067] Furthermore, this utility model is not limited to the above-described embodiments, and can be appropriately modified without departing from the spirit of the invention. That is, the above description has been appropriately omitted and simplified for the purpose of clarity, and those skilled in the art can easily modify, add to, and transform the various elements of the embodiments within the scope of this utility model.

Claims

1. A battery pack, characterized by, Possessing: a battery fastening link member having a fastening link portion that fixes a battery module having a connecting portion to a case with the connecting portion by a connecting portion; a front-rear direction structural member disposed near a side portion of the case and extending in a front-rear direction; a plurality of left-right direction structural members whose end portions abut the front-rear direction structural member and which are disposed orthogonally to the front-rear direction structural member and extend in a left-right direction; and a load transmission member disposed near a side portion of at least one of the case and fixed throughout the front-rear direction structural member and the left-right direction structural member, in a case where the battery module is disposed between two adjacent left-right direction structural members of the plurality of left-right direction structural members, that is, inside in the front-rear direction, and is fixed to the case with the connecting portion and the fastening link portion, at least a portion of an end portion of the front-rear direction structural member of the load transmission member is disposed at a position inside in the front-rear direction from the fastening link portion.

2. The battery pack according to claim 1, wherein the battery module is rectangular in shape extending in the front-rear direction and the left-right direction, in the case, the connecting portion possessed by the battery module is formed protruding from each corner portion of the rectangular battery module to the side portion side of the case near thereto, at least a portion of the end portion of the front-rear direction structural member of the load transmission member is disposed at a position inside in the front-rear direction from the connecting portion closest to the load transmission member via the side portion of the case and the connecting portion.

3. The battery pack according to claim 1 or 2, wherein the end portion of the front-rear direction structural member of the load transmission member has a shape extending in at least one of the front-rear direction, in a case where the end portion of the front-rear direction structural member of the load transmission member has a shape extending in the front direction, at least a portion of a site extending in the front direction is disposed at a position on the front side from a fastening link portion disposed at a rearmost position among the fastening link portions corresponding to the connecting portions of the battery module disposed on the front side near the load transmission member, in a case where the end portion of the front-rear direction structural member of the load transmission member has a shape extending in the rear direction, at least a portion of a site extending in the rear direction is disposed at a position on the rear side from a fastening link portion disposed at a foremost position among the fastening link portions corresponding to the connecting portions of the battery module disposed on the rear side near the load transmission member.

4. The battery pack according to claim 1 or 2, wherein the load transmission member is a first load transmission member having a site extending in the front direction and a second load transmission member having a site extending in the rear direction, the first load transmission member and the second load transmission member are respectively provided corresponding to the plurality of left-right direction structural members, The distance from the rear end of the second load transmission member arranged corresponding to the leftward and rightward structural members in front to the front end of the first load transmission member arranged corresponding to the leftward and rightward structural members in back is shorter than the length obtained by adding the distance from the front end to the rear end of the first load transmission member and the distance from the front end to the rear end of the second load transmission member.

5. The battery pack according to claim 1 or 2, wherein The load transmission member has a notch that avoids contact with the battery fastening member.

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