Bus bar and battery pack for vehicles

Abstract

To prevent an electrode terminal of a battery module from being exposed in the case of vehicle collision, etc.SOLUTION: A bus bar 3 for connecting electrode terminals 13 of battery modules 2 which are adjacent to each other comprises: a bus bar main body 14 including a bar part 15 and a connection part 16 for connections to the electrode terminals 13 in both ends of the bar part 15; and a cover part 20 for covering the electrode terminals 13 connected by the connection part 16. In the bar part 15, there is formed a protrusion 18 protruding from the cover part 20 in a direction away from the battery module 2.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a bus bar and a vehicle battery pack.

Background Art

[0002] In a vehicle battery pack mounted on a vehicle such as an electric vehicle or a hybrid vehicle, when a plurality of battery modules are installed, the electrode terminals of adjacent battery modules are connected by a bus bar. Patent Document 1 discloses a configuration in which, in a battery pack and a secondary battery including the same, in order to connect sub-modules in series, a connection bus bar bent into a predetermined shape is provided between adjacent sub-modules.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Among bus bars for connecting the electrode terminals of adjacent battery modules, there are those provided with a cover portion of an insulating material for covering the electrode terminals, which are high-voltage portions. However, when the vehicle body or the sheet metal constituting the exterior of the battery pack is deformed and contacts the cover portion during a vehicle collision or the like, the cover portion may be damaged and the electrode terminals may be exposed.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to prevent the electrode terminals of the battery module from being exposed during a vehicle collision or the like.

Means for Solving the Problems

[0006] The bus bar of the present invention is a bus bar for connecting between electrode terminals of adjacent battery modules, and includes a bus bar main body having a bar portion and connection portions for connecting to the electrode terminals at both ends of the bar portion, and a cover portion for covering the electrode terminals to which the connection portions are connected, wherein a protruding portion protruding in a direction away from the battery module is formed on the bar portion, which is more distant from the battery module than the cover portion.

Effect of the Invention

[0007] According to the present invention, it is possible to prevent the electrode terminals of the battery module from being exposed during a vehicle collision or the like.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0009] A bus bar 3 according to an embodiment of the present invention is a bus bar 3 for connecting between electrode terminals 13 of adjacent battery modules 2, and includes a bus bar main body 14 having a bar portion 15 and connection portions 16 for connecting to the electrode terminals 13 at both ends of the bar portion 15, and a cover portion 20 for covering the electrode terminals 13 to which the connection portions 16 are connected. A protruding portion 18 protruding in a direction away from the battery module 2 is formed on the bar portion 15, which is more distant from the battery module 2 than the cover portion 20. As a result, when the vehicle body or the sheet metal forming the exterior of the battery pack is deformed during a vehicle collision or the like, first, it comes into contact with the protruding portion 18 of the bus bar 3 and receives the impact load at the protruding portion 18. Therefore, it is possible to avoid applying a load to the cover portion 20 and causing damage, and to prevent the electrode terminal 13 of the battery module 2 from being exposed.

Embodiment

[0010] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing a vehicle battery pack 1 according to an embodiment. FIG. 2 is a plan view showing battery modules 2L, 2M, and 2R included in the vehicle battery pack 1. FIG. 3 is a view showing a bus bar 3 according to the embodiment, where (a) is a front view of the bus bar 3 and (b) is a bottom view of the bus bar 3. FIG. 4 is a perspective view showing the vehicle battery pack 1 according to the embodiment (in a state where the back upper cover 7 and the back cover 8 are removed). FIG. 5 is a view for explaining the peripheral structure of the bus bar 3 in the vehicle battery pack 1, showing a cross-section taken along line V-V in FIG. 4. In the following description, the battery modules 2L, 2M, and 2R may also be collectively referred to as the battery module 2. The front-rear, left-right, and up-down directions (the directions shown in FIGS. 1, 2, 4, and 5) described below are based on the vehicle on which the vehicle battery pack 1 is mounted.

[0011] As shown in FIG. 1, a vehicle battery pack (hereinafter simply referred to as "battery pack") 1 includes a top cover 4, left and right side covers 5, a front upper cover 6, a back upper cover 7, a back cover 8, a bottom cover 9 (see FIG. 5), etc., which constitute its exterior. Each cover 4 to 9 is made of sheet metal or the like. In addition, the battery pack 1 is provided with an inlet unit 10 for introducing cooling air and an outlet unit 11 for exhausting cooling air.

[0012] As shown in Fig. 2, three battery modules 2L, 2M, and 2R are installed in the battery pack 1 in this embodiment. Each of the battery modules 2L, 2M, and 2R is a known one, and although its detailed description is omitted, it has a structure in which a plurality of unit cells are stacked, and electrode terminals 13 are provided on both end faces 12 facing in the stacking direction. As shown in Fig. 2, in a state where the battery pack 1 is mounted on a vehicle, the battery modules 2L, 2M, and 2R are arranged in parallel, and the electrode terminals 13 of each of the battery modules 2L, 2M, and 2R are arranged to face front and back. The electrode terminals 13 provided on the front end faces 12 of the left battery module 2L and the central battery module 2M are connected by a bus bar 3. Also, the electrode terminals 13 provided on the rear end faces 12 of the right battery module 2R and the central battery module 2M are connected by a bus bar 3. In this way, the three battery modules 2L, 2M, and 2R are connected in series.

[0013] As shown in Fig. 3, the bus bar 3 includes a bus bar body 14 made of a conductor such as copper. The bus bar body 14 has a thin plate-shaped bar portion 15 and thin plate-shaped connection portions 16 at both ends thereof. The connection portion 16 is made wider than the bar portion 15, and a hole 17 for inserting the electrode terminal 13 is formed. On the bar portion 15, for example, by bending, a protruding portion 18 protruding in a direction away from the battery module 2 is formed. The protruding portion 18 has a pair of inclined surfaces 18a that incline in a direction approaching the central portion in the longitudinal direction of the bus bar 3 from each connection portion 16 side, and an end surface 18b connecting these pair of inclined surfaces 18a.

[0014] The periphery of the bar portion 15 is covered with an insulating material 19 made of a synthetic resin or the like. Also, cover portions 20 for covering the electrode terminals 13 to which the connection portions 16 are connected are integrally formed at both ends of the insulating material 19. The cover portion 20 has a substantially box shape or a dome shape that opens on the connection portion 16 side, and as shown in Fig. 3(b), in a bottom view, the connection portion 16 is located inside thereof. If the top portion 20a of the cover portion 20 is made into an openable lid, the connection work between the connection portion 16 and the electrode terminal 13 becomes easier.

[0015] As shown in FIG. 3(a), the protruding portion 18 protrudes in a direction away from the battery module 2 with respect to the cover portion 20 (see the virtual line l). That is, as shown in FIG. 2, in the case of the front bus bar 3, the protruding portion 18 protrudes forward with respect to the cover portion 20, and in the case of the rear bus bar 3, the protruding portion 18 protrudes rearward with respect to the cover portion 20. Also, as shown in FIG. 3(a), in the longitudinal direction of the bus bar 3, the maximum width H of the protruding portion 18 is larger than the maximum width h of the cover portion 20.

[0016] Next, with reference to FIGS. 4 and 5, the arrangement of the bus bar 3 in the battery pack 1 will be described in more detail. As shown in FIG. 4, in the battery pack 1, a duct 21 that forms a flow path for cooling air is arranged in the region above the battery modules 2L, 2M, and 2R so as to extend in the left-right direction (vehicle width direction). The end portion of the duct 21 extends rearward and is located above the bus bar 3.

[0017] Also, as shown in FIGS. 4 and 5, brackets 22 are arranged on the end face 12 side of the battery modules 2L, 2M, and 2R. The bracket 22 is a bracket for fixing the three battery modules 2L, 2M, and 2R and fixing them to the bottom cover 9 or the like that constitutes the bottom of the battery pack 1. On the rear side, the bracket 22 has a wall surface portion 22a along the end face 12 of the battery modules 2L, 2M, and 2R, and a lower surface portion 22b that is bent at the lower end of the wall surface portion 22a so as to protrude in a direction away from the end face 12 (that is, rearward).

[0018] As shown in FIG. 5, a virtual line L is defined as a line connecting the end portion 21a on the rear side of the duct 21 and the end portion of the lower surface portion 22b of the bracket 22. The protruding portion 18 of the bus bar 3 is arranged in the space S surrounded by the virtual line L, the duct 21, the bracket 22, and the battery modules 2L, 2M, and 2R. In this way, the duct 21 and the bracket 22 have portions located in a direction away from the battery module 2 with respect to the protruding portion 18 of the bus bar 3. Note that in FIG. 5, the peripheral structure of the bus bar 3 at the rear is shown, but the same structure may be provided at the front as well.

[0019] As described above, in the bus bar 3, the protruding portion 18 protrudes in a direction away from the battery module 2 more than the cover portion 20. Therefore, when the vehicle body or the sheet metal constituting the exterior of the battery pack is deformed during a vehicle collision or the like, it first contacts the protruding portion 18 of the bus bar 3 and receives the impact load at the protruding portion 18. In the example of FIG. 2, when another vehicle or the like collides with the rear portion of the vehicle (the collision direction is indicated by an arrow) and the back cover 8 made of sheet metal is deformed, it first contacts the protruding portion 18 of the bus bar 3 and receives the impact load at the protruding portion 18. Thereby, it is possible to avoid applying a load to the cover portion 20 and causing damage, and to prevent the electrode terminal 13 of the battery module 2 from being exposed.

[0020] Also, as shown in FIG. 3(a), in the longitudinal direction of the bus bar 3, the maximum width H of the protruding portion 18 is made larger than the maximum width h of the cover portion 20. Therefore, when the vehicle body or the sheet metal contacts the protruding portion 18 during a vehicle collision, it becomes easier to disperse the load by securing the contact area. Also, even if the vehicle body or the sheet metal hits the protruding portion 18 off-center, it becomes easier to protect the cover portion 20.

[0021] Also, the battery pack 1 includes a member having a portion located in a direction away from the battery module 2 more than the protruding portion 18 of the bus bar 3. In this embodiment, the duct 21 and the bracket 22 have portions located in a direction away from the battery module 2 more than the protruding portion 18 of the bus bar 3. Thereby, when the vehicle body or the sheet metal is deformed at the initial stage during a vehicle collision, it first contacts the duct 21 or the bracket 22 and the impact is mitigated. Along with this, the power when colliding with the bus bar 3 is weakened, the load applied to the protruding portion 18 is reduced, and it becomes possible to more effectively prevent the electrode terminal 13 of the battery module 2 from being exposed.

[0022] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, each embodiment merely shows a specific example in the implementation of the present invention. The technical scope of the present invention is not limited to each embodiment. The present invention can be variously modified without departing from its gist, and these are also included in the technical scope of the present invention. For example, the arrangement such as the number of battery modules 2 in the battery pack 1 and the orientation of the battery modules 2 is not limited.

Description of Reference Numerals

[0023] 1: Battery pack, 2(2L, 2M, 2R): Battery module, 3: Bus bar, 12: End face, 13: Electrode terminal, 14: Bus bar body, 15: Bar portion, 16: Connection portion, 17: Hole, 18: Protrusion, 18a: Inclined surface, 18b: End face, 19: Insulating material, 20: Cover portion, 21: Duct, 22: Bracket

Claims

1. A bus bar for connecting between electrode terminals of adjacent battery modules, comprising a bus bar body having a bar portion and connection portions for connecting to the electrode terminals at both ends of the bar portion, and a cover portion for covering the electrode terminals to which the connection portions are connected, wherein a protruding portion protruding in a direction away from the battery module is formed on the bar portion, the protruding portion being more distant from the battery module than the cover portion.

2. An insulating material covering the periphery of the bar portion is provided, and the cover portion is integrally formed with the insulating material. The bus bar according to claim 1, characterized in that.

3. In the longitudinal direction of the bus bar, the maximum width of the protruding portion is larger than the maximum width of the cover portion. The bus bar according to claim 1, characterized in that.

4. A vehicle battery pack mounted on a vehicle, adjacent battery modules, a bus bar according to any one of claims 1 to 3 for connecting between electrode terminals of the adjacent battery modules, and a member having a portion located in a direction away from the battery module relative to the protruding portion of the bus bar. The vehicle battery pack is characterized by this.

5. a duct forming a flow path of cooling air, disposed in a region around the battery module, and a bracket disposed on an end face side where the electrode terminal of the battery module is provided, wherein at least one of the duct and the bracket has a portion located in a direction away from the battery module relative to the protruding portion of the bus bar. The vehicle battery pack according to claim 4, characterized in that.

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