Connection structure of battery cells

Abstract

To provide a connection structure of battery cells capable of reducing the load on terminals.SOLUTION: The connection structure of battery cells includes: a first bus bar that is connected to a terminal of a battery cell; and a second bus bar connected between the first bus bars of adjacent battery cells. The first bus bar and the second bus bar are connected via a roller.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a battery cell connection structure. [Background technology]

[0002] Patent Document 1 discloses a technique in which a bus bar is provided with a bent portion to suppress the application of an excessive load to the terminals of a battery cell when the battery cell expands. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-207442 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology disclosed in Patent Document 1, the bus bars are directly fixed to the terminals, so when the battery cells expand and the bus bars stretch, the terminals are likely to be subjected to a load.

[0005] The present disclosure has been made in consideration of the above, and has an object to provide a battery cell connection structure that can reduce the load on the terminals. [Means for solving the problem]

[0006] The battery cell connection structure of the present disclosure comprises a first bus bar connected to a terminal of a battery cell and a second bus bar connecting the first bus bars of adjacent battery cells, the first bus bar and the second bus bar being connected via rollers. Effect of the Invention

[0007] According to the present disclosure, the first bus bar and the second bus bar are connected via rollers, and the first bus bar slides relative to the second bus bar when the battery cell expands, thereby reducing the load on the terminals. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a battery cell connection structure according to an embodiment, where (a) is a view showing the battery cell before expansion, and (b) is a view showing the battery cell after expansion. [Diagram 2] FIG. 2 is a side view showing a battery cell connection structure according to an embodiment, where (a) is a view showing the battery cell before expansion, and (b) is a view showing the battery cell after expansion. [Diagram 3] FIG. 3 is a perspective view showing a state in which the battery cell according to the embodiment is being assembled. [Figure 4] FIG. 4 is a perspective view showing a modified example of the battery cell connection structure according to the embodiment, showing the battery cell after expansion. [Diagram 5] FIG. 5 is a side view showing a modified example of the battery cell connection structure according to the embodiment, where (a) is a view showing the battery cell before expansion, and (b) is a view showing the battery cell after expansion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A battery cell connection structure according to an embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that are easily replaceable by a person skilled in the art, or those that are substantially the same.

[0010] The battery cell according to the embodiment is used as a battery for, for example, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a battery electric vehicle (BEV), or the like.

[0011] Fig. 1 is a perspective view showing a battery cell connection structure according to an embodiment, and Fig. 2 is a side view showing the battery cell connection structure according to an embodiment. As shown in the figures, the battery cell connection structure according to the embodiment includes a plurality of battery cells 1, a plurality of first bus bars 3, and a plurality of second bus bars 5.

[0012] The battery cell 1 is provided with two terminals 2. One of the two terminals 2 is a positive terminal, and the other of the two terminals 2 is a negative terminal.

[0013] The first bus bar 3 is formed in a rod shape. One end side of the first bus bar 3 is connected to the terminal 2. In other words, the one end side of the first bus bar 3 is fixed to the terminal 2 by, for example, welding or the like.

[0014] The second bus bar 5 is formed in a plate shape. The second bus bar 5 connects the first bus bars 3 of the adjacent battery cells 1.

[0015] The first busbar 3 and the second busbar 5 are connected via rollers 4. That is, rollers 4 are provided on the other end side of the first busbar 3. The first busbar 3 contacts the lower surface of the second busbar 5 via these rollers 4. The first busbar 3 is configured to be slidable in a predetermined direction relative to the lower surface of the second busbar 5 by the rollers 4.

[0016] Note that the above-mentioned "the other end side of the first bus bar 3" refers to the end side of the first bus bar 3 opposite the side connected to the terminal 2. Also, the above-mentioned "predetermined direction (the direction in which the rollers 4 slide)" refers to the direction in which the battery cell 1 expands, as will be described later. Also, while this embodiment shows an example in which the rollers 4 are provided on the first bus bar 3 side, the rollers 4 may also be provided on the second bus bar 5 side.

[0017] Here, when the battery cells 1 deteriorate and expand, the battery cells 1 begin to move away from each other in a predetermined direction, as shown in (b) of Fig. 1. If the first bus bar and the second bus bar are fixed as in the conventional case, the load (stress) will be concentrated on the terminals of the battery cells, which may cause problems such as electrolyte leakage due to damage or deformation of the terminals.

[0018] Therefore, in the battery cell connection structure according to the embodiment, the first bus bar 3 and the second bus bar 5 are not fixed, but are brought into contact with each other via rollers 4, thereby solving the above problem. In the battery cell connection structure according to the embodiment, as shown in FIG. 2(b), for example, even if the battery cells 1 deteriorate and expand, the rollers 4 slide on the lower surface of the second bus bar 5, and the battery cells 1 move away from each other. As a result, no load (stress) is generated on the terminals 2 of the battery cells 1.

[0019] 3 is a perspective view showing how a battery cell according to an embodiment is assembled. When assembling a battery cell 1 to a module, as shown in the figure, insulating rubber 8 is sandwiched and assembled on top of second bus bar 5 between under cover 6 and upper cover 7 of the module, so that roller 4 and the underside of second bus bar 5 are in close contact with each other.

[0020] (Modification) Fig. 4 is a perspective view showing a modified example of the battery cell connection structure according to the embodiment, and Fig. 5 is a side view showing a modified example of the battery cell connection structure according to the embodiment. In the example shown in Fig. 1 and Fig. 2, rollers 4 are provided on all of the first bus bars 3 of the multiple battery cells 1, but rollers 4 may be provided on only some of the first bus bars 3.

[0021] 4, for example, a structure may be used in which a first busbar 3 without rollers 4 is fixed to the positive electrode terminal 2a, and a first busbar 3 with rollers 4 is fixed to the negative electrode terminal 2b. In this case, one end of the first busbar 3 is fixed to the terminal 2 by, for example, welding. Similarly, the other end of the first busbar 3 without rollers 4 is fixed to the second busbar 5 by welding or the like.

[0022] In this modification, the first busbar 3, which does not include rollers 4, is made of a rigid material. Furthermore, in this modification, the rollers 4 and the lower surface of the second busbar 5 are brought into close contact with each other by using a second busbar 5 that is bent downward when viewed from the side as shown in Fig. 5 .

[0023] In the modified battery cell connection structure according to the embodiment having such a configuration, even if the battery cells 1 deteriorate and expand, the rollers 4 slide on the lower surface of the second busbar 5, and the battery cells 1 move away from each other, as shown in (b) of Fig. 5, for example. Therefore, no load (stress) is generated on the terminals 2 of the battery cells 1.

[0024] According to the battery cell connection structure according to the embodiment described above, the first bus bar 3 and the second bus bar 5 are connected via the rollers 4, and when the battery cell 1 expands, the first bus bar 3 slides relative to the second bus bar 5. This makes it possible to reduce the load on the terminal 2, the positive electrode terminal 2a, and the negative electrode terminal 2b.

[0025] Further advantages and modifications may readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof.

[0026] For example, in the battery cell connection structure of the embodiment, the first bus bar 3 and the second bus bar 5 are connected via rollers 4, but the structure may also be such that the first bus bar 3 and the second bus bar 5 are connected via an elastic member (such as a spring). [Explanation of symbols]

[0027] 1 Battery Cell 2 Terminal 2a Positive terminal 2b Negative terminal 3 First bus bar 4. Lola 5 Second bus bar 6 Undercover 7 Upper cover 8. Insulating rubber

Claims

[Claim 1] A first bus bar connected to a terminal of the battery cell; a second bus bar connecting the first bus bars of adjacent battery cells; Equipped with The first bus bar and the second bus bar are connected via a roller. Battery cell connection structure.

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