Battery Module

Abstract

To provide a battery module that restrains a manufacturing cost from being increased due to an excessive design.SOLUTION: A battery module comprises: a plurality of battery cells which are arrayed in a first direction and which each have a housing and an electrode element provided on the housing; a plate-like bus bar for connecting the electrode terminals of the plurality of battery cells; a voltage detection line for detecting a voltage of the bus bar; and a conductive clip member which is electrically connected to the voltage detection line and which is energized to sandwich at least a part of the bus bar.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present technology relates to a battery module. [Background technology]

[0002] For example, as shown in Patent Documents 1 and 2, a bus bar and a conductor, or two bus bars, have conventionally been connected to each other by clamping them with a clip member.

[0003] Furthermore, Patent Document 3 discloses an open / close type test connection terminal for connecting lead wires to a switchboard terminal or the like when testing and measuring the voltage and current of a main circuit of a switchboard, distribution board, or the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-51999 [Patent Document 2] JP 2014-154246 A [Patent Document 3] JP 2009-176662 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the structure for connecting the voltage detection line to the bus bar, a screw fastening structure and a welding structure are used. However, when a screw fastening structure or a welding structure is adopted, the manufacturing cost increases. For example, the resistance value required for the connection structure between the voltage detection line and the bus bar is on the order of mΩ, but when a welding structure is adopted, the resistance value is on the order of μΩ, which may result in overdesign.

[0006] An object of the present technology is to provide a battery module in which increases in manufacturing costs due to overdesign are suppressed. [Means for solving the problem]

[0007] The present technology provides the following battery module.

[0008] [1] A battery module comprising: a plurality of battery cells arranged in a first direction, each of the battery cells having a housing and an electrode terminal provided on the housing; a plate-shaped bus bar connecting the electrode terminals of the plurality of battery cells; a voltage detection wire for detecting the voltage of the bus bar; and a conductive clip member electrically connected to the voltage detection wire and biased to clamp at least a portion of the bus bar.

[0009] [2] The battery module described in [1], wherein the voltage detection line is crimped and connected to the clip member from a first direction.

[0010] [3] The battery module according to [1] or [2], wherein the clip member includes a U-shaped portion that clamps the bus bar.

[0011] [4] The battery cell according to [3], wherein the U-shaped portion is fitted to the bus bar from a second direction perpendicular to the first direction.

[0012] [5] The battery module according to any one of [1] to [4], wherein the bus bar has a groove portion that receives a part of the clip member.

[0013] [6] The battery module according to [5], wherein the groove is formed on both sides of the bus bar.

[0014] [7] The battery module according to any one of [1] to [6], further comprising a wall portion surrounding at least a portion of the bus bar and the clip member.

[0015] [8] The battery module according to [7], wherein the wall portion is made of insulating resin.

[0016] [9] The battery module according to any one of [1] to [8], wherein the housings of the multiple battery cells have a rectangular shape.

[0017]

[10] The battery module according to any one of [1] to [9], wherein the plurality of battery cells are lithium ion battery cells. Effect of the Invention

[0018] According to the present technology, it is possible to avoid an increase in the manufacturing cost of a battery module due to overdesign. Since a large current does not flow through the voltage detection line, the required resistance value specification can be satisfied without necessarily adopting a welded structure. [Brief description of the drawings]

[0019] [Figure 1] FIG. 2 is a diagram showing a basic configuration of a battery module. [Diagram 2] FIG. 2 is a perspective view showing a battery cell. [Diagram 3] FIG. 4 is a diagram showing the arrangement of bus bars in a battery module. [Figure 4] FIG. 4 is an exploded perspective view showing a connection structure between a bus bar and a voltage detection line in a battery module. [Diagram 5] 4 is a perspective view showing a connection structure between a bus bar and a voltage detection line in a battery module. FIG. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 5. [Figure 7] 13 is a cross-sectional view showing a modified example of the connection structure between the bus bar and the voltage detection line. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof will not be repeated.

[0021] In the embodiments described below, when referring to the number, amount, etc., the scope of the present technology is not necessarily limited to the number, amount, etc., unless otherwise specified. In addition, in the following embodiments, each component is not necessarily essential to the present technology, unless otherwise specified. In addition, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiment.

[0022] In this specification, the words "comprise", "include" and "have" are open-ended, i.e., when a certain configuration is included, other configurations may or may not be included.

[0023] Furthermore, when geometric terms and terms expressing positional and directional relationships, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along" are used in this specification, these terms allow for manufacturing errors and slight variations. When terms expressing relative positional relationships, such as "upper side" and "lower side," are used in this specification, these terms are used to indicate relative positional relationships in one state, and the relative positional relationships can be inverted or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0024] In this specification, the term "battery" is not limited to lithium ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium ion batteries. In this specification, the term "electrode" may collectively refer to positive and negative electrodes. In addition, the term "electrode plate" may collectively refer to positive and negative plates.

[0025] In this specification, a "battery cell" can be mounted in a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric vehicle (BEV), etc. However, the use of the "battery cell" is not limited to being mounted in a vehicle.

[0026] 1 is a diagram showing the basic configuration of a battery module 1. As shown in FIG. 1, the battery module 1 includes a battery cell 100, an end plate 200, and a restraining member 300.

[0027] The multiple battery cells 100 are arranged side by side in the Y-axis direction (first direction). This forms a stack of the battery cells 100. The battery cells 100 include electrode terminals 110. Separators (not shown) are interposed between the multiple battery cells 100. The multiple battery cells 100 sandwiched between the two end plates 200 are pressed by the end plates 200 and are restrained between the two end plates 200.

[0028] The end plates 200 are disposed on both ends of the battery module 1 in the Y-axis direction. The end plates 200 are fixed to a base such as a case that houses the battery module 1. The restraining members 300 connect the two end plates 200 to each other.

[0029] By fixing the restraining member 300 to the end plate 200 while a compressive force in the Y-axis direction is applied to the stack of multiple battery cells 100 and end plates 200, and then releasing the compressive force, a tensile force acts on the restraining member 300 connecting the two end plates 200. In reaction to this, the restraining member 300 presses the two end plates 200 in a direction that brings them closer to each other.

[0030] Fig. 2 is a perspective view showing the battery cell 100. As shown in Fig. 2, the battery cell 100 has a rectangular shape. The battery cell 100 has an electrode terminal 110 and a housing 120 (external can). In other words, the battery cell 100 is a rectangular secondary battery cell.

[0031] The electrode terminal 110 is formed on the housing 120. The electrode terminal 110 has a positive electrode terminal 111 and a negative electrode terminal 112 aligned along an X-axis direction (second direction) perpendicular to a Y-axis direction (first direction). The positive electrode terminal 111 and the negative electrode terminal 112 are provided apart from each other in the X-axis direction.

[0032] The housing 120 has a rectangular parallelepiped shape and forms the external appearance of the battery cell 100. The housing 120 includes a case body 120A that contains an electrode body and an electrolyte (not shown), and a sealing plate 120B that seals an opening of the case body 120A. The sealing plate 120B is joined to the case body 120A by welding.

[0033] The housing 120 has an upper surface 121, a lower surface 122, a first side surface 123, a second side surface 124, and two third side surfaces 125. The housing 120 is provided with a gas exhaust valve 126.

[0034] The upper surface 121 is a plane perpendicular to the Z-axis direction (third direction) perpendicular to the Y-axis direction and the X-axis direction. The electrode terminals 110 are disposed on the upper surface 121. The lower surface 122 faces the upper surface 121 along the Z-axis direction.

[0035] Each of the first side surface 123 and the second side surface 124 is formed of a plane perpendicular to the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has the largest area among the multiple side surfaces of the housing 120. Each of the first side surface 123 and the second side surface 124 has a rectangular shape when viewed in the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has a rectangular shape with the X-axis direction being the long side direction and the Z-axis direction being the short side direction when viewed in the Y-axis direction.

[0036] The multiple battery cells 100 are stacked such that the first side surfaces 123 and the second side surfaces 124 of the battery cells 100 adjacent to each other in the Y-axis direction face each other. As a result, the positive electrode terminals 111 and the negative electrode terminals 112 are arranged alternately in the Y-axis direction in which the multiple battery cells 100 are stacked.

[0037] Gas exhaust valve 126 is provided on top surface 121. When the temperature of battery cell 100 rises (thermal runaway) and the internal pressure of housing 120 exceeds a predetermined value due to gas generated inside housing 120, gas exhaust valve 126 exhausts the gas to the outside of housing 120.

[0038] Fig. 3 is a diagram showing the arrangement of bus bars 400 in the battery module 1. In the example of Fig. 3, the positive electrode terminals 111 and negative electrode terminals 112 of adjacent battery cells 100 are electrically connected by the bus bars 400, and the multiple battery cells 100 are electrically connected in series.

[0039] That is, the battery module 1 includes a plurality of battery cells 100, each having an electrode terminal 110, arranged along a predetermined direction, and a bus bar 400 that connects the electrode terminals 110 of the plurality of battery cells 100 together. The bus bar 400 is a plate-like member having a thickness of, for example, about 0.8 mm or more and 1.5 mm or less. The bus bar 400 is made of, for example, aluminum, copper, or the like.

[0040] Fig. 4 is an exploded perspective view showing a connection structure between busbar 400 and voltage detection wire 600. Fig. 5 is a perspective view showing a state in which busbar 400 and voltage detection wire 600 shown in Fig. 4 are connected, and Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5. Fig. 7 is a cross-sectional view showing a connection structure between busbar 400 and voltage detection wire 600 according to a modified example.

[0041] 4 to 7, clip member 500 made of a conductive material includes a U-shaped portion that clamps bus bar 400. Clip member 500 is made of, for example, nickel-plated brass. Clip member 500 is fitted onto bus bar 400 from the X-axis direction. Clip member 500 is biased so as to clamp bus bar 400.

[0042] In order to verify that each battery cell 100 included in the battery module 1 is performing as expected, it is common to measure the potential of each bus bar 400. A voltage detection line 600 is provided to measure the voltage of each bus bar 400.

[0043] A commonly used copper wire can be used as the voltage detection wire 600. The voltage detection wire 600 is connected (for example, by tab crimping) to the clip member 500 from the Y-axis direction. This electrically connects the clip member 500 and the voltage detection wire 600.

[0044] 5, bus bar 400 is provided on a bus bar module including a plate 700 and a wall portion 800. Wall portion 800 is provided so as to surround at least a portion of bus bar 400 and clip member 500. Plate 700 and wall portion 800 are made of, for example, an insulating resin.

[0045] The bus bar 400 is placed in an area of ​​the plate 700 that is surrounded by the wall portion 800. The plate 700 is provided above a plurality of battery cells 100 that are arranged in the Y-axis direction. The wall portion 800 is also adjacent to the clip member 500 that is connected to the bus bar 400. This can prevent the clip member 500 from being unintentionally detached from the bus bar 400.

[0046] A groove 410 that receives a part of the clip member 500 is formed in the bus bar 400. As shown in Figures 5 and 6, a protrusion 510 provided on the clip member 500 engages with the groove 410 of the bus bar 400. This fixes the positions of the clip member 500 and the voltage detection line 600.

[0047] Groove portion 410 may be formed on both sides of bus bar 400 as shown in Fig. 6, or may be formed on only one side of bus bar 400 as shown in Fig. 7. For convenience of illustration, plate 700 and wall portion 800 are not shown in Figs. 6 and 7.

[0048] When connecting the voltage detection line 600 to the bus bar 400, the resistance value required for the connection structure is on the order of milliohms. Therefore, if a welding structure with a resistance value on the order of microohms is adopted, this may result in overdesign.

[0049] In contrast, in the battery module 1 according to the present embodiment, the bus bar 400 and the voltage detection wire 600 are electrically connected by engaging the clip member 500 with the bus bar 400. At this time, since a large current does not flow through the voltage detection wire 600, the required resistance value specification can be satisfied without necessarily welding between the bus bar 400 and the clip member 500. As a result of the above, it is possible to avoid an increase in the manufacturing cost of the battery module 1 due to overdesign.

[0050] Although the embodiment of the present technology has been described above, the embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0051] 1 battery module, 100 battery cell, 110 electrode terminal, 111 positive electrode terminal, 112 negative electrode terminal, 120 housing, 120A case body, 120B sealing plate, 121 upper surface, 122 lower surface, 123 first side surface, 124 second side surface, 125 third side surface, 126 gas exhaust valve, 200 end plate, 300 restraining member, 400 bus bar, 410 groove portion, 500 clip member, 510 protrusion portion, 600 voltage detection line, 700 plate, 800 wall portion.

Claims

1. A plurality of battery cells arranged in a first direction, each of the battery cells having a housing and an electrode terminal provided on the housing; a plate-shaped bus bar that connects the electrode terminals of the plurality of battery cells; A voltage detection line for detecting a voltage of the bus bar; a conductive clip member electrically connected to the voltage detection line and biased to clamp at least a portion of the bus bar; the bus bar has a groove that receives a portion of the clip member.

2. The battery module according to claim 1 , wherein the clip member includes a U-shaped portion that clamps the bus bar.

3. The battery module according to claim 2 , wherein the U-shaped portion is fitted to the bus bar from a second direction perpendicular to the first direction.

4. The battery module according to claim 1 , wherein the grooves are formed on both sides of the bus bar.

5. The battery module according to claim 1 , further comprising a wall portion surrounding at least a portion of the bus bar and the clip member.

6. The battery module according to claim 5 , wherein the wall portion is made of an insulating resin.

7. The battery module according to claim 1 , wherein the housings of the plurality of battery cells have a rectangular shape.

8. The battery module according to claim 1 , wherein the plurality of battery cells are lithium ion battery cells.

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