Battery module

Abstract

To provide a battery module in which a part can be easily replaced. [Solution] The battery module 1 comprises a plurality of divided holders 110 that each accommodate one end of a plurality of battery blocks 23 and connect at least some of the plurality of battery cells 20 included in each of the plurality of battery blocks 23 in parallel with each other, a detachable bus bar 140 that electrically connects the plurality of divided holders 110 so as to connect the plurality of battery blocks 23 in series, and one base holder 130 that accommodates the other end of the plurality of battery blocks 23 so as to sandwich the plurality of battery blocks 23 together with the plurality of divided holders 110.

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a battery module including multiple divided holders that each house multiple battery cells. In this battery module, the multiple battery cells are sandwiched between positive and negative current collector plates and electrically connected. This structure, in which current collector plates are arranged to sandwich the multiple battery cells, is called a double-sided current collector structure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2016 / 31208 Summary of the Invention [Problem to be solved by the invention]

[0004] Although Patent Document 1 discloses the concept of dividing multiple battery cells into groups for handling, the use of a double-sided current collection structure means that multiple divided holders are integrally configured and cannot be detached, making it difficult to replace only some of the divided holders, and there is room for improvement.

[0005] An object of the present disclosure is to provide a battery module that allows easy replacement of a portion thereof. [Means for solving the problem]

[0006] The present disclosure provides: a plurality of divided holders that respectively accommodate one end of the plurality of battery blocks and connect at least some of the plurality of battery cells included in each of the plurality of battery blocks in parallel to one another; a detachable series connection portion that electrically connects the plurality of divided holders so as to connect the plurality of battery blocks in series; a base holder that accommodates the other ends of the battery blocks so as to sandwich the battery blocks together with the divided holders; A battery module is provided. [Effects of the Invention]

[0007] According to the present disclosure, a battery module that allows easy replacement of a portion can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a battery module according to an embodiment of the present disclosure. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] FIG. 1 is a first perspective view showing a current collecting structure. [Figure 7] FIG. 2 is a second perspective view showing the current collection structure. [Figure 8] FIG. 3 is a third perspective view showing the current collection structure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Specific examples of the present disclosure will be described in detail below with reference to the drawings. In the following description, terms indicating specific directions or positions may be used as necessary. However, the use of these terms is intended to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present disclosure. Furthermore, parts with the same reference numerals appearing in multiple drawings indicate identical or equivalent parts or components. Furthermore, the embodiments described below illustrate specific examples of the technical ideas of the present disclosure and do not limit the present disclosure to the following. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. Furthermore, the content described in one embodiment or example may also be applicable to other embodiments or examples. Furthermore, the sizes and positional relationships of components shown in the drawings may be exaggerated for clarity.

[0010] FIG. 1 shows a battery module 1 according to an embodiment of the present disclosure.

[0011] [Application] The battery module 1 is applied, for example, to an emergency power source such as a battery backup unit (BBU), a power source for a traction motor of an electric vehicle, etc. However, the use of the battery module 1 is not particularly limited, and it can be used as a power source for various other electrical devices.

[0012] [Exterior] The battery module 1 has a box-shaped exterior case 10 that extends in the longitudinal direction. A handle 11 for carrying is attached to one longitudinal end of the exterior case 10. Although not shown in detail, a connector for supplying power is provided at the other longitudinal end of the exterior case 10.

[0013] [Overall structure] FIG. 2 shows an exploded perspective view of the battery module 1. As shown in FIG.

[0014] The battery module 1 has, inside an exterior case 10, a plurality of battery cells 20, a cell holder 100 that holds the plurality of battery cells 20 in a sandwiched manner, a circuit board 30, a fan unit 40, and a control unit 50. The exterior case 10 is configured to be separated into an upper and lower section.

[0015] [Battery cell] FIG. 3 is a perspective view showing one of the plurality of battery cells 20. As shown in FIG.

[0016] In this embodiment, each of the multiple battery cells 20 is a cylindrical lithium-ion secondary battery. Each of the multiple battery cells 20 has an outer can 21 and a cap 22. The outer can 21 is a bottomed cylindrical battery with an opening at one end in the axial direction DX (the upper end in FIG. 3 ), which constitutes a negative electrode terminal. The cap 22 is disposed at one end in the axial direction DX, seals the opening of the outer can 21 via an insulating material, and constitutes a positive electrode terminal (see the shaded area). That is, each of the multiple battery cells 20 constitutes a positive electrode terminal at the cap 22 in the center of the top, and constitutes a negative electrode terminal at the side surface portion 21 a, bottom surface portion 21 b, and top edge portion 21 c. Note that the polarity may be reversed.

[0017] In this embodiment, the battery module 1 has 98 battery cells 20. The 98 battery cells 20 are divided into seven battery blocks 23A to 23G. Each of the seven battery blocks 23A to 23G includes 14 battery cells 20. However, this number can be changed as appropriate depending on the required design. Hereinafter, when the seven battery blocks 23A to 23G are not to be distinguished from one another, they will simply be referred to as battery blocks 23.

[0018] [Cell holder] 4 shows a perspective view of the cell holder 100. Note that FIG. 4 is shown upside down compared to FIG.

[0019] In this embodiment, the cell holder 100 has seven divided holders 110A to 110G and one base holder 130. However, the number of divided holders can be changed as appropriate depending on the required design. Hereinafter, when the seven divided holders 110A to 110G are described without distinction, they will also be simply referred to as divided holders 110.

[0020] FIG. 5 is a perspective view showing the divided holder 110. As shown in FIG.

[0021] The divided holder 110 accommodates one end of the battery block 23 (the upper end in FIGS. 4 and 5). The divided holder 110 is made of an insulating material such as synthetic resin and is formed, for example, by injection molding. The divided holder 110 has a cell accommodation section 111 that accommodates one end of the multiple battery cells 20, and a placement section 112 on which an insulating sheet 120 or the like is placed.

[0022] The cell housing portion 111 has a shape complementary to one end of the plurality of battery cells 20. In the illustrated example, the cell housing portion 111 holds 14 battery cells 20 arranged in a staggered pattern.

[0023] The mounting section 112 has an edge 113 including a rib 113a that rises from the cell housing section 111 toward the opposite side to the multiple battery cells 20. Inside the rib 113a is a current collection structure including an insulating sheet 120, several current collector plates, and several lead plates. The current collection structure will be described later, but in Figure 5, only the topmost insulating sheet 120 is visible. The insulating sheet 120 has multiple C-shaped gas vent holes 120a that function as gas vent valves.

[0024] Fig. 6 is a first perspective view showing the current collecting structure, which shows a state in which insulating sheet 120, current collecting plate 125 (described later), and current collecting plate 129 (described later) have been removed from Fig. 5.

[0025] In this embodiment, each of the multiple battery blocks 23 includes a first parallel block 24 (on the front left side of FIG. 6) in which seven battery cells 20 are connected in parallel, and a second parallel block 25 (on the back right side of FIG. 6) in which seven battery cells 20 are similarly connected in parallel. Each of the multiple divided holders 110 houses the first parallel block 24 and the second parallel block 25 side by side.

[0026] On the first parallel block 24 side, lead plate 121, current collector plate 122, insulating sheet 123, lead plate 124, and current collector plate 125 (see FIG. 5) are stacked in this order from the bottom up. Similarly, on the second parallel block side, lead plate 124, current collector plate 126, insulating sheet 127, lead plate 128, and current collector plate 129 (see FIG. 5) are stacked in this order from the bottom up. Note that lead plate 124 is arranged across both the first parallel block 24 side and the second parallel block 25 side.

[0027] Fig. 7 is a second perspective view showing the current collection structure, in which current collector plate 122, insulating sheet 123, lead plate 124, and current collector plate 125 on the first parallel block 24 side, and lead plate 124 and current collector plate 129 on the second parallel block 25 side are removed from Fig. 6.

[0028] Fig. 8 is a third perspective view showing the current collecting structure, in which current collecting plate 126, insulating sheet 127, lead plate 128, and current collecting plate 129 on the second parallel block 25 side are removed from Fig. 6.

[0029] 7, the top edges (negative electrode terminals) 21c of the multiple battery cells 20 in the first parallel block 24 are electrically connected to a lead plate 121. Here, the top edges (negative electrode terminals) 21c and the lead plate 121 are welded together. This also applies to the electrical connections between the subsequent lead plates 124, 128 and the multiple battery cells 20. The lead plate 121 has a tab 121a that extends downward from the side surface. A hole is provided in the tab 121a for fastening to a bus bar 140 (see FIG. 4), which will be described later, and a screw 121b is attached to the hole.

[0030] 8, the caps (positive electrode terminals) 22 of the multiple battery cells 20 in the first parallel block 24 are electrically connected to a lead plate 124. The lead plate 124 is also electrically connected to the top edges (negative electrode terminals) 21c of the multiple battery cells 20 in the second parallel block 25. Therefore, the first parallel block 24 and the second parallel block 25 are connected in series.

[0031] 7, the caps (positive electrode terminals) 22 of the multiple battery cells 20 in the second parallel block 25 are electrically connected to a lead plate 128. The lead plate 128 has a tab 128a that extends downward from the side surface. The tab 128a has a hole for fastening to a bus bar 140 (see FIG. 4), which will be described later, and a screw 128b is attached to the hole.

[0032] 4, tabs 121a on the first parallel block 24 side of a certain divided holder (e.g., 110B) are electrically connected to tabs 128a on the second parallel block 25 side of another divided holder (e.g., 110A) via a plurality of bus bars (series connections) 140 that are reversibly connected. Tabs 128a on the second parallel block 25 side of a certain divided holder (e.g., 110B) are electrically connected to tabs 121a on the first parallel block 24 side of another divided holder (e.g., 110C) via a plurality of bus bars (series connections) 140 that are reversibly connected. Here, "reversibly connected" refers to a connection that can be easily released, and in this embodiment, the bus bars 140 are configured to be detachable.

[0033] Bus bar 140 is a conductive metal plate. Tabs 121a, 128a and bus bar 140 are fastened together by screws 121b, 128b. By releasing the fastening by screws 121b, 128b and removing bus bar 140, the electrical connection between multiple split holders 110 can be easily released.

[0034] The base holder 130 accommodates the other ends (lower ends in FIG. 4 ) of the multiple battery blocks 23. The base holder 130 is made of an insulating material such as synthetic resin and is formed, for example, by injection molding. The base holder 130 has cell accommodation sections 131 that accommodate the multiple battery blocks 23 by sandwiching them together with the multiple segment holders 110. The base holder 130 has partition walls 132 between each of the segment holders 110.

[0035] The cell housing portion 131 has a shape complementary to the other end portions (lower end portions in FIG. 4 ) of the multiple battery cells 20, and houses the other end portions of the multiple battery cells 20. In the illustrated example, the cell housing portion 131 is partitioned into seven housing regions 131a to 131g corresponding to the seven divided holders 110A to 110G. The seven housing regions 131a to 131g are separated from one another by partition walls 132. The partition walls 132 are part of the base holder 130 and are configured integrally with the cell housing portion 131, rather than being separate from it. In other words, the base holder 130 is made up of a single component. Overall, the cell housing portion 131 holds 98 battery cells 20 arranged in a staggered pattern. The base holder 130 has a length roughly equal to the total length of the multiple divided holders 110A to 110G.

[0036] The base holder 130 does not have a structure that provides electrical connection to the multiple battery cells 20, and does not have conductive members such as lead plates or current collector plates. In other words, the battery module 1 of this embodiment employs a one-sided current collection structure in which the electrical connection structure is concentrated on the side of the multiple divided holders 110. With a one-sided current collection structure, the base holder 130 does not require complex fixing to the multiple battery cells 20, such as welding. Therefore, the multiple battery cells 20 can be easily inserted and removed from the base holder 130.

[0037] [substrate] 2, the substrate 30 is disposed adjacent to the cell holder 100. The substrate 30 has various control functions in cooperation with the control device 50, which will be described later.

[0038] [Fan device] 2, the fan device 40 is disposed on one longitudinal end side (left side in FIG. 2) of the cell holder 100. The fan device 40 has a fan for taking in outside air and blowing it onto the plurality of battery cells 20 to cool the plurality of battery cells 20.

[0039] [Control device] 2, the control device 50 is disposed on the other end side in the longitudinal direction (the right side in FIG. 2) of the cell holder 100. The control device 50 has various control functions together with the substrate.

[0040] [Action and effect] The battery module 1 according to the above embodiment can achieve the following advantageous effects.

[0041] Because the bus bar 140 and the divided holder 110 are joined with screws 121b and 128b and are configured to be detachable, the connection between the multiple battery blocks 23 can be released by removing the bus bar 140. This allows each of the multiple divided holders 110 to be easily removed from the base holder 130. For example, if an abnormality is found in only some of the multiple battery blocks 23, only the divided holder 110 that houses the battery block 23 that is found to be abnormal can be removed and replaced.

[0042] Since the structure having electrical connections exists only in the multiple split holders 110 and not in the base holder 130, each split holder 110 can be easily removed by cutting the electrical connections between the multiple split holders 110.

[0043] Furthermore, because the cell holder 100 is divided, welding of the lead plates 121, 124, 128 to the multiple battery cells 20 can be performed on a small scale for each of the multiple divided holders 110. If the cell holder 100 were not divided, large-scale welding equipment would be required, but by dividing it as in this embodiment, small-scale welding equipment is possible. This also makes parallel welding possible, shortening the lead time for the welding process. Furthermore, the constraints on finish accuracy and processing precision that are required for large-scale welding equipment can be alleviated.

[0044] Furthermore, bus bars (DC connection parts) 140 are attached to the side surfaces of each of the plurality of divided holders 110, and therefore can be easily attached and detached.

[0045] Furthermore, since a plurality of bus bars 140 that are reversibly joined are used as DC connection sections between a plurality of divided holders 110, DC connection can be achieved with a simple configuration.

[0046] Furthermore, since the base holder 130 has the partition walls 132 between the divided holders 110, the insulation between the divided holders 110 can be strengthened, thereby improving safety.

[0047] Furthermore, the presence of ribs on edge 113 of divided holder 110 improves the strength of the divided holder itself, improving workability and safety during installation and disassembly.

[0048] Furthermore, in each of the multiple divided holders 110, the multiple battery cells 20 are connected in parallel and in DC, ensuring a high degree of design freedom in terms of voltage, arrangement, etc. Furthermore, compared to a configuration in which the multiple divided holders 110 are not connected in DC, the number of tabs 121a, 128a and bus bars 140 can be reduced, simplifying the configuration.

[0049] Although the embodiments have been described above, the above configurations can be modified in various ways within the scope of the present disclosure.

[0050] In the above embodiment, the plurality of battery cells 20 are lithium ion batteries, but they may be secondary batteries other than lithium ion batteries, such as all-solid-state batteries.

[0051] In the above embodiment, the DC connection between the plurality of divided holders 110 is the bus bar 140, but the DC connection may be formed of other conductive members such as lead wires or a substrate.

[0052] The present disclosure may include the following aspects. (Aspect 1) a plurality of divided holders that respectively accommodate one end of the plurality of battery blocks and connect at least some of the plurality of battery cells included in each of the plurality of battery blocks in parallel to one another; a detachable series connection portion that electrically connects the plurality of divided holders so as to connect the plurality of battery blocks in series; a base holder that accommodates the other ends of the battery blocks so as to sandwich the battery blocks together with the divided holders; A battery module comprising: (Aspect 2) 2. The battery module according to claim 1, wherein the series connection portion is attached so as to connect side surfaces of the plurality of divided holders. (Aspect 3) 3. The battery module of claim 1, wherein the series connection includes a plurality of reversibly joined bus bars. (Aspect 4) Aspect 4. The battery module of aspect 3, wherein the reversibly joined bus bars are fastened to the split holders with screws. (Aspect 5) each of the plurality of battery blocks includes a first parallel block in which a plurality of battery cells are connected in parallel with each other and a second parallel block in which another plurality of battery cells are connected in parallel with each other; 5. The battery module according to any one of aspects 1 to 4, wherein each of the plurality of divided holders connects the first parallel block and the second parallel block in series. (Aspect 6) 6. The battery module according to any one of aspects 1 to 5, wherein the base holder is made of an insulating material. (Aspect 7) 7. The battery module of claim 1, wherein the base holder includes a partition wall between adjacent divided holders. (Aspect 8) Aspect 8. The battery module of any one of aspects 1 to 7, wherein the plurality of divided holders include ribs on edges. [Explanation of symbols]

[0053] 1 Battery Module 10 Outer case 11 Handle 20 battery cells 21 Outer can 21a Side part 21b Bottom part 21c Apex 22 Cap 23, 23A~23G Battery Block 24 First Parallel Block 25 Second Parallel Block 30 boards 40 Fan unit 50 Control device 100 Cell Holder 110, 110A~110G Split holder 111 Cell storage unit 112 Placement section 113 Edge 113a Rib 120 Insulation sheet 120a Gas vent hole 121 Reed plate 121a Tab 121b Screw 122 Current collector plate 123 Insulation Sheet 124 Reed plate 125 Current collector plate 126 Current collector plate 127 Insulation Sheet 128 Reed Plate 128a Tab 128b Screw 129 Current collector plate 130 Base holder 131 Cell storage unit 131a~131g Containment Area 132 Partition Wall 140 Busbar (DC connection)

Claims

1. a plurality of divided holders that respectively accommodate one end of the plurality of battery blocks and connect at least some of the plurality of battery cells included in each of the plurality of battery blocks in parallel to one another; a detachable series connection portion that electrically connects the plurality of divided holders so as to connect the plurality of battery blocks in series; a base holder that accommodates the other ends of the battery blocks so as to sandwich the battery blocks together with the divided holders; Equipped with the series connection portion is attached so as to connect the side surfaces of the plurality of divided holders, the series connection portion includes a plurality of reversibly joined bus bars; the reversibly joined bus bars are fastened by screws to holes in tabs of lead plates that extend downward from side surfaces of the divided holders; The direction in which the screws are inserted into and removed from the tab holes is perpendicular to the side surfaces of the plurality of divided holders.

2. each of the plurality of battery blocks includes a first parallel block in which a plurality of battery cells are connected in parallel with each other and a second parallel block in which another plurality of battery cells are connected in parallel with each other; The battery module according to claim 1 , wherein each of the plurality of divided holders connects the first parallel block and the second parallel block in series.

3. The battery module according to claim 1 or 2, wherein the base holder is made of an insulating material.

4. The battery module according to claim 1 , wherein the base holder includes a partition wall between adjacent divided holders.

5. The battery module according to claim 1 or 2, wherein the plurality of divided holders include ribs on their edges.

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