Battery pack

Abstract

To provide a battery pack with high manufacturing efficiency.SOLUTION: A battery pack includes a plurality of battery cells arranged in a first direction, and a bus bar that electrically connects the battery cells. The battery cells each include a housing having a first side surface and a second side surface that face each other in a second direction that is orthogonal to the first direction, and an electrode terminal provided on the first side surface or the second side surface. The bus bar and the electrode terminal include parts that are adjacent to each other in a third direction that is orthogonal to the first direction and the second direction. In the adjacent parts, the bus bar and the electrode terminal are joined together.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] International Publication No. 2017 / 130706 (Patent Document 1) discloses a battery pack in which electrode terminals are provided on the upper surfaces of battery cells, and the electrode terminals of a plurality of battery cells are connected by bus bars. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 130706 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, various variations in the shape of battery cells may arise due to demands for improved mountability in vehicles, etc. Depending on the shape of the battery cells, it is necessary to adopt a connection structure that can improve manufacturing efficiency.

[0005] An object of the present technology is to provide a battery pack that can be manufactured with high efficiency. [Means for solving the problem]

[0006] The present technology provides the following assembled battery.

[0007] [1] An assembled battery comprising: a plurality of battery cells arranged in a first direction; and a bus bar electrically connecting the plurality of battery cells, wherein the plurality of battery cells each include a housing having a first side surface and a second side surface that face each other in a second direction that is perpendicular to the first direction; and an electrode terminal provided on the first side surface or the second side surface, wherein the bus bar and the electrode terminal have portions that are adjacent to each other in a third direction that intersects the first direction and the second direction, and the bus bar and the electrode terminal are joined to each other at the adjacent portions.

[0008] [2] The battery pack according to [1], wherein the bus bar and the electrode terminal are joined by laser welding.

[0009] [3] The battery pack according to [1] or [2], wherein the bus bar and the electrode terminal are provided on both the first side surface and the second side surface.

[0010] [4] The battery pack according to any one of [1] to [3], wherein the bus bars are arranged to sandwich the electrode terminals in the third direction.

[0011] [5] The battery pack according to any one of [1] to [4], wherein the bus bar has a portion that is sandwiched between the plurality of electrode terminals in the first direction. [Effects of the Invention]

[0012] According to the present technology, it is possible to provide a battery pack that can be manufactured with high efficiency. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a perspective view showing an example of a battery pack. [Figure 2] FIG. 2 is a side view of the battery pack shown in FIG. [Figure 3] FIG. 10 is a perspective view showing another example of a battery pack. [Figure 4] FIG. 4 is a side view of the battery pack shown in FIG. 3. [Figure 5]FIG. 10 is a perspective view (part 1) showing still another example of a battery pack. [Figure 6] FIG. 10 is a perspective view (part 2) showing still another example of the battery pack. [Figure 7] 7 is a cross-sectional view taken along line VII-VII in FIGS. 5 and 6. FIG. [Figure 8] FIG. 10 is a perspective view (part 3) showing still another example of the battery pack. [Figure 9] FIG. 9 is a side view of the battery pack shown in FIG. 8. [Figure 10] FIG. 9 is a top view of the battery pack shown in FIG. 8. [Figure 11] FIG. 9 is a front view of the battery pack shown in FIG. 8. [Figure 12] FIG. 10 is a perspective view (part 4) showing still another example of the battery pack. [Figure 13] FIG. 13 is a side view of the battery pack shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] 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 may not be repeated.

[0015] In the embodiments described below, when numbers, amounts, etc. are mentioned, the scope of the present technology is not necessarily limited to those numbers, amounts, etc., unless otherwise specified. Furthermore, in the following embodiments, each component is not necessarily essential to the present technology, unless otherwise specified. Furthermore, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiments.

[0016] In this specification, the terms "comprise," "include," and "have" are open-ended. That is, when a certain feature is included, other features may or may not be included.

[0017] Furthermore, when geometric terms and terms expressing positional and directional relationships are used in this specification, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along," 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 a single state, and the relative positional relationships can be reversed or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0018] In this specification, the term "battery" typically refers to a lithium-ion battery, but the scope of the present technology is not limited thereto and may include other batteries such as nickel-metal hydride batteries and sodium-ion batteries. In this specification, the term "electrode" may collectively refer to a positive electrode and a negative electrode.

[0019] In this specification, a "battery cell" is typically a prismatic cell, but the scope of the present technology is not necessarily limited to this and may include cells of other shapes, such as cylindrical, pouch, and blade types. Furthermore, the "battery cell" can be installed in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs). However, the use of the "battery cell" is not limited to in-vehicle use.

[0020] FIG. 1 is a perspective view showing an example of a battery pack 1, and FIG. 2 is a side view of the battery pack 1 shown in FIG.

[0021] As shown in Figures 1 and 2, the battery pack 1 includes battery cells 100 and a bus bar 200. The battery cells 100 are arranged along the Y-axis direction (first direction). Although two battery cells 100 are shown in Figures 1 and 2, the battery pack 1 may include three or more battery cells 100.

[0022] The battery cell 100 includes a housing 110 and electrode terminals 120. An electrode body is housed inside the housing 110. The housing 110 has a first side surface 111 and a second side surface 112 that face each other in the X-axis direction (second direction) that is perpendicular to the Y-axis direction. Two electrode terminals 120 (a positive terminal and a negative terminal) are provided on the first side surface 111 and the second side surface 112, respectively. The two electrode terminals 120 may be provided on either the first side surface 111 or the second side surface 112.

[0023] 1, the electrode terminals 120 are provided on the first side surface 111 and the second side surface 112 that face each other in the X-axis direction, which makes it possible to reduce the height (total length in the Z-axis direction) of the battery cell 100. As a result, the mountability of the battery cell 100 in a vehicle is improved.

[0024] The bus bar 200 electrically connects the plurality of battery cells 100. The bus bar 200 is joined to the electrode terminal 120. The bus bar 200 and the electrode terminal 120 are joined by, for example, laser welding.

[0025] Busbar 200 and electrode terminal 120 have portions that are adjacent to each other in the Z-axis direction (third direction) that is perpendicular to (intersects) the Y-axis direction and the X-axis direction. Specifically, first portion 210 of busbar 200 and electrode terminal 120 are adjacent to each other in the Z-axis direction. By irradiating laser light from above first portion 210 (+Z side), first portion 210 of busbar 200 and electrode terminal 120 are joined to each other (laser welded).

[0026] Busbar 200 is formed by bending a plate-shaped member (conductive member) made of a metal such as copper or aluminum. After being bent, busbar 200 has a shape such as that shown in FIGS. 1 and 2. Busbar 200 shown in FIGS. 1 and 2 is curved so as to have a substantially U-shape between two electrode terminals 120. In other words, busbar 200 shown in FIGS. 1 and 2 has a portion that is sandwiched between multiple electrode terminals 120 in the Y-axis direction.

[0027] The shape of bus bar 200 is not limited to that shown in FIGS. 1 and 2, and for example, bus bar 200 in a flat plate shape may be arranged on the upper side (+Z side) of electrode terminal 120.

[0028] FIG. 3 is a perspective view showing another example of the battery pack 1, and FIG. 4 is a side view of the battery pack 1 shown in FIG.

[0029] 3 and 4, both ends of the bus bar 200 in the Y-axis direction are extended, and the bus bar 200 is formed so as to sandwich two electrode terminals 120 in the Y-axis direction. In this way, the bus bar 200 can be used to determine the relative positioning of the two battery cells 100 in the Y-axis direction.

[0030] 5 and 6 are perspective views showing still another example of the battery pack 1, and FIG. 7 is a cross-sectional view taken along line VII-VII in FIGS. 5 and 6 (common to FIGS. 5 and 6).

[0031] In the examples of Figures 5 to 7, busbar 200 is arranged to cover electrode terminal 120 in the Y-axis direction (both the +Y side and the -Y side), the X-axis direction (only the +X side for busbar 200 shown in Figures 5 to 7, and only the -X side for busbar 200 on the opposite side), and the Z-axis direction (both the +Z side and the -Z side).

[0032] 5 and 6, the bus bar 200 is arranged to sandwich the electrode terminal 120 in the Y-axis direction and the Z-axis direction. In this way, the bus bar 200 can be used to position the two battery cells 100 relative to each other in the Y-axis direction and the Z-axis direction.

[0033] In the example of Figure 6, the central portion of the busbar 200 in the Y-axis direction protrudes in the X-axis direction (direction away from the battery cell 100) and has a roughly U-shape, so the displacement absorption ability of the busbar 200 in the Y-axis direction is higher than in the example of Figure 5.

[0034] 5 to 7, bus bar 200 has first portion 210 located on the +Z side of electrode terminal 120. By irradiating laser light from above (the +Z side) of first portion 210, first portion 210 of bus bar 200 and electrode terminal 120 are joined to each other (laser welding).

[0035] FIG. 8 is a perspective view showing yet another example of the battery pack 1, and FIGS. 9 to 11 are a side view, a top view, and a front view, respectively, of the battery pack 1 shown in FIG.

[0036] 8 to 11, the electrode terminals 120 have a substantially L-shape when viewed from the Y-axis direction. Each electrode terminal 120 has a protruding portion 121 that protrudes in the X-axis direction. The bus bar 200 has a first portion 210 located above (on the +Z side of) the protruding portion of the electrode terminal 120, and a hole 220 that receives the protruding portion 121 of the electrode terminal 120.

[0037] 8 to 11, by irradiating laser light from the upper side (+Z side) of the first portion 210, the first portion 210 of the bus bar 200 and the protruding portion 121 of the electrode terminal 120 are joined to each other (laser welding).

[0038] In the examples of FIGS. 8 to 11, the battery pack 1 is shown with five battery cells 100 arranged, but the number of arranged battery cells 100 can be changed as desired.

[0039] In addition, in the examples of Figures 8 to 11, the electrode terminals 120 of five battery cells 100 are connected by one bus bar 200, but the number of electrode terminals 120 connected by one bus bar 200 can be changed as desired.

[0040] FIG. 12 is a perspective view showing still another example of the battery pack 1, and FIG. 13 is a side view of the battery pack 1 shown in FIG.

[0041] 12 and 13, electrode terminal 120 also has a substantially L-shape when viewed from the Y-axis direction. Electrode terminal 120 has a protruding portion 121 that protrudes in the X-axis direction. Bus bar 200 also has a first portion 210 located above (on the +Z side of) the protruding portion of electrode terminal 120, and a hole 220 that receives protruding portion 121 of electrode terminal 120. However, the shape of protruding portion 121 of electrode terminal 120 and the shape of hole 220 of bus bar 200 are different from those in the examples of FIGS. 8 to 11.

[0042] 12 and 13, by irradiating laser light from the upper side (+Z side) of the first portion 210, the first portion 210 of the bus bar 200 and the protruding portion 121 of the electrode terminal 120 are joined to each other (laser welding).

[0043] As described above, in the battery pack 1 shown in this embodiment, even in the battery pack 1 consisting of battery cells 100 having a structure (horizontal terminal structure) in which electrode terminals 120 are provided on a first side surface 111 and a second side surface 112 that face each other in the X-axis direction, it is possible to join the first portion 210 of the bus bar 200 and the protruding portion 121 of the electrode terminal 120 by irradiating laser light from the upper side (+Z side) of the first portion 210 of the bus bar 200.

[0044] As described above, according to the technology of the present embodiment, even in a battery with a structure (lateral terminal structure) different from conventional batteries in which the electrode terminals are arranged on the sealing plate on the upper side (+Z side) of the battery cell, it is possible to join the bus bar 200 and the electrode terminal 120 by laser welding from the +Z side. That is, even for a battery assembly 1 that has a different basic structure from conventional ones, it is possible to laser weld the bus bar 200 and the electrode terminal 120 by using the same manufacturing equipment and performing the same steps as conventional ones. As a result, according to the technology of the present embodiment, it is possible to improve the manufacturing efficiency of the battery assembly 1.

[0045] Although the embodiments of the present technology have been described above, the embodiments disclosed herein should be considered to be 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 meaning and scope of the claims. [Explanation of symbols]

[0046] 1 battery pack, 100 battery cell, 110 housing, 111 first side surface, 112 second side surface, 120 electrode terminal, 200 bus bar, 210 first portion, 220 hole portion.

Claims

1. a plurality of battery cells arranged in a first direction; a bus bar electrically connecting the plurality of battery cells, each of the plurality of battery cells includes a housing having a first side surface and a second side surface that face each other in a second direction that is orthogonal to the first direction, and an electrode terminal provided on the first side surface or the second side surface; the bus bar and the electrode terminal have portions that are adjacent to each other in a third direction that intersects the first direction and the second direction, and the bus bar and the electrode terminal are joined to each other at the adjacent portions.

2. The battery pack according to claim 1 , wherein the bus bars and the electrode terminals are joined by laser welding.

3. 3. The battery pack according to claim 1, wherein the bus bars and the electrode terminals are provided on both the first side surface and the second side surface.

4. 3. The battery pack according to claim 1, wherein the bus bars are arranged to sandwich the electrode terminals in the third direction.

5. 3. The battery pack according to claim 1, wherein the bus bar has a portion sandwiched between a plurality of the electrode terminals in the first direction.

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