JP2023137379A - Power storage module - Google Patents

Abstract

An object of the present invention is to improve insulation between a plurality of conductive connection parts. A power storage module 1 includes a cell stack 10 and one or more insulating members 20. The cell stack 10 has a plurality of conductive connections 11. The conductive connection portion 11 is such that the positive electrode terminal 101 of one cell 100 among the plurality of cells 100 and the negative electrode terminal 102 of the cell adjacent to the one cell among the plurality of cells are electrically connected to each other in the one direction D. It is formed by being connected to. One or more insulating members 20 cover a portion of the cell stack 10. One or more insulating members 20 are made of a cured insulating adhesive and cover the plurality of conductive connections 11 . [Selection diagram] Figure 1

Description

The present disclosure relates to a power storage module.

Japanese Patent Application Laid-open No. 2013-229266 (Patent Document 1) discloses that a plurality of flat batteries each having an electrode tab led out from an end are arranged in a stacked manner, and a bus bar of a bus bar module provided along the end is provided with the above-mentioned battery. A battery module is disclosed in which electrode tabs are joined. One of the pair of electrode tabs is a positive electrode, and the other is a negative electrode. The plurality of batteries are stacked in alternate directions so that the electrode tabs on the positive electrode side and the electrode tabs on the negative electrode side alternate. By connecting adjacent positive electrode tabs and negative electrode tabs to each other, the plurality of batteries are connected in series as a whole.

JP2013-229266A

In the electricity storage module disclosed in Patent Document 1, a conductive connection portion is formed by electrically connecting an electrode tab (terminal) on the positive electrode side and an electrode tab (terminal) on the negative electrode side to each other. The power storage module has a plurality of conductive connections. The plurality of conductive connections are located apart from each other. This ensures insulation between the plurality of conductive connections.

However, no other member is located between the plurality of conductive connections. Therefore, the conductive connection parts may be electrically connected to each other by water generated due to dew condensation, electrolyte leaked from the cell, foreign matter mixed in from the outside, or the like. This may cause a short circuit in the power storage module.

The present disclosure has been made in view of the above problems, and provides an electricity storage module that can improve the insulation between a plurality of conductive connection parts formed by electrically connecting the terminals of a plurality of cells to each other. The purpose is to

A power storage module according to one aspect of the present disclosure includes a cell stack and one or more insulating members. The cell stack has a plurality of cells stacked in one direction. Each of the plurality of cells has a positive terminal and a negative terminal. The positive electrode terminal protrudes in a direction perpendicular to the one direction. The negative electrode terminal protrudes in a direction perpendicular to the one direction. The cell stack has a plurality of conductive connections. The conductive connection portion is formed by electrically connecting a positive electrode terminal of one of the plurality of cells and a negative electrode terminal of a cell adjacent to the one cell among the plurality of cells in the above-mentioned one direction. It is formed. One or more insulating members cover a portion of the cell stack. The one or more insulating members are made of a cured insulating adhesive and cover the plurality of conductive connections.

According to the above configuration, the insulating member can prevent electrical connection between the conductive connection parts due to water generated by condensation, electrolyte leaked from the cell, or foreign matter mixed in from the outside. The insulation properties between the plurality of conductive connections can be improved compared to a case where the conductive connections are simply located apart from each other without using any other member between them.

According to the present disclosure, it is possible to improve the insulation between a plurality of conductive connection parts formed by electrically connecting terminals of a plurality of cells to each other.

FIG. 1 is a schematic cross-sectional view showing a power storage module according to an embodiment of the present disclosure. FIG. 2 is a flow diagram showing a method for manufacturing a power storage module according to an embodiment of the present disclosure. FIG. 2 is a schematic cross-sectional view showing a prepared cell stack. FIG. 2 is a schematic cross-sectional view showing a cell laminate partially immersed in an adhesive. FIG. 2 is a schematic cross-sectional view showing a cell stack partially covered with an insulating member.

Hereinafter, a power storage module according to an embodiment of the present disclosure will be described. In the following description of the embodiments, the same or corresponding parts in the figures are denoted by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 is a schematic cross-sectional view showing a power storage module according to an embodiment of the present disclosure. The power storage module 1 according to an embodiment of the present disclosure is mounted, for example, on an electric vehicle such as an electric vehicle. As shown in FIG. 1, the power storage module 1 includes a cell stack 10, one or more insulating members 20, a housing 30, and a filling part 40.

The cell stack 10 has a plurality of cells 100 stacked in one direction D. Although five cells 100 are shown in FIG. 1, the number of cells 100 is not particularly limited. Examples of the cell 100 include a lithium ion battery. The cell 100 is a so-called laminate type cell.

Each of the plurality of cells 100 has a positive terminal 101, a negative terminal 102, and a main body case 103.

The positive electrode terminal 101 protrudes from the main body case 103 in a direction perpendicular to the one direction D mentioned above. The positive electrode terminal 101 is made of metal, for example aluminum. Although the shape of the positive electrode terminal 101 is not particularly limited, it is, for example, sheet-shaped.

The negative electrode terminal 102 protrudes from the main body case 103 in a direction perpendicular to the one direction D mentioned above. Negative electrode terminal 102 is made of metal, for example copper. Although the shape of the negative electrode terminal 102 is not particularly limited, it is, for example, sheet-shaped. In each of the plurality of cells 100, the positive terminal 101 and the negative terminal 102 protrude in opposite directions.

The main body case 103 has a substantially flat outer shape. The main body case 103 is arranged so that its length (thickness) in the one direction D is the thinnest.

Inside the main body case 103, a part of the positive electrode terminal 101, a part of the negative electrode terminal 102, a separator, a pair of current collector plates, a laminate film, and an electrolytic solution (all not shown) are accommodated. Inside the main body case 103, the pair of current collector plates are electrically connected to the positive terminal 101 and the negative terminal 102, respectively. Note that the cell 100 may be configured with an all-solid-state battery having a solid electrolyte instead of a separator and an electrolyte.

The cell stack 10 has a plurality of conductive connections 11. The conductive connection portion 11 is such that the positive electrode terminal 101 of one cell 100 among the plurality of cells 100 and the negative electrode terminal 102 of the cell adjacent to the one cell among the plurality of cells are electrically connected to each other in the one direction D. It is formed by being connected to. Thereby, the plurality of cells 100 are electrically connected in series. The conductive connection portion 11 is adjacent to another conductive connection portion 11 in the one direction D.

In the conductive connection portion 11, the positive electrode terminal 101 and the negative electrode terminal 102 are bent in the one direction D mentioned above. As a result, the tip of the positive electrode terminal 101 and the tip of each of the negative electrode terminals 102 are opposed to each other. These tips may be electrically connected, for example by being directly welded together.

Further, the conductive connection portion 11 may further include a bus bar made of metal. In this case, the positive terminal 101 and the negative terminal 102 are electrically connected in the conductive connection portion 11 via the bus bar. The bus bar, positive electrode terminal 101, and negative electrode terminal 102 are connected, for example, by welding.

The cell stack 10 further includes a pair of lead electrodes 12A and 12B. The positive electrode side extraction electrode 12A includes a positive terminal 101 that does not constitute a conductive connection portion 11 in the cell stack 10. The positive electrode side extraction electrode 12A may include only the positive terminal 101, or may further include a bus bar connected to the positive terminal 101 and an external terminal connected to this bus bar. At least a portion of the extraction electrode 12A is adjacent to one of the plurality of conductive connection parts 11 in the one direction D.

The negative electrode side extraction electrode 12B includes a negative electrode terminal 102 that does not constitute a conductive connection portion 11 in the cell stack 10. The negative electrode side extraction electrode 12B may include only the negative terminal 102, or may further include a bus bar connected to the negative terminal 102 and an external terminal connected to this bus bar. At least a portion of the extraction electrode 12B is adjacent to one of the plurality of conductive connection parts 11 in the one direction D.

The cell stack 10 may further include one or more expansion absorbers. The expansion absorbing material is made of a dilatancy material. Thereby, the expansion absorbing material limits the relative displacement of the plurality of cells 100 with respect to the housing 30 in the one direction D. The expansion absorbing material is arranged in line with the plurality of cells 100. The expansion absorbing material is arranged, for example, so as to be further lined up on one side in one direction D when viewed from the plurality of cells 100. The expansion absorbing materials may be arranged so as to be further lined up on both sides of one direction D when viewed from the plurality of cells 100. Expansion absorbent material may be placed between cells 100. When the cell stack 10 has a plurality of expansion absorbers, the number of expansion absorbers is preferably smaller than the number of cells 100.

One or more insulating members 20 cover a portion of the cell stack 10. One or more insulating members 20 entirely cover each of the plurality of conductive connections 11 . A gap is formed between the insulating member 20 covering the conductive connection part 11 and the insulating member 20 covering another conductive connection part 11 adjacent to the conductive connection part 11 in one direction. Thereby, the volume of the entire insulating member 20 becomes relatively small, and the manufacturing cost and weight of the power storage module 1 can be reduced.

The insulating member 20 further covers a portion of each of the pair of extraction electrodes 12A, 12B. Of the pair of extraction electrodes 12A and 12B, a portion adjacent to the conductive connection portion 11 in one direction D is covered with an insulating member 20. Of the pair of extraction electrodes 12A and 12B, a portion adjacent to the main body case 103 in one direction D is not covered with the insulating member 20. Thereby, the volume of the entire insulating member 20 becomes relatively small, and the manufacturing cost and weight of the power storage module 1 can be reduced.

In this embodiment, the insulating member 20 covers only the surface of the main body case 103 of each of the plurality of cells 100 on the side from which the positive electrode terminal 101 and the negative electrode terminal 102 protrude. Thereby, the volume of the insulating member 20 becomes relatively small, and the manufacturing cost and weight of the power storage module 1 can be reduced.

One or more insulating members 20 are made of a cured insulating adhesive. Moreover, it is preferable that the insulating member 20 has relatively high thermal conductivity. Thereby, it is possible to suppress a decrease in the heat dissipation performance of the heat generated in the conductive connection portion 11 due to the insulating member 20.

The housing 30 accommodates the cell stack 10 and the insulating member 20. A portion of each of the pair of extraction electrodes 12A and 12B is extracted from the casing 30. The housing 30 is made of metal such as aluminum.

The filling part 40 is made of an insulating material. The filling part 40 extends in the one direction D mentioned above. The filling part 40 is joined to the insulating member 20 and the housing 30. Thereby, the filling part 40 fixes the relative position of the cell stack 10 with respect to the housing 30. Note that the filling part 40 is not in direct contact with the conductive connection part 11. Thereby, short-circuiting of the conductive connection parts 11 along the creeping surface of the filling part 40 extending in the one direction D can be suppressed.

Next, a method for manufacturing the electricity storage module 1 according to an embodiment of the present disclosure will be described. FIG. 2 is a flow diagram illustrating a method for manufacturing a power storage module according to an embodiment of the present disclosure. As shown in FIG. 2, the method for manufacturing the electricity storage module 1 according to the embodiment of the present disclosure includes a preparation step S1, a dipping step S2, a drying step S3, an assembling step S4, a filling step S5, and a sealing step S5. and a stopping step S6.

FIG. 3 is a schematic cross-sectional view showing the prepared cell stack. As shown in FIG. 3, in a preparation step S1, a cell stack 10 is prepared.

FIG. 4 is a schematic cross-sectional view showing a cell laminate partially immersed in adhesive. As shown in FIG. 4, in the dipping step S2, a part of the cell laminate 10 is dipped in the insulating adhesive 20A. It is preferable that the insulating adhesive 20A has relatively high thermal conductivity. Specifically, a portion of the cell laminate 10 is dipped in the insulating adhesive 20A multiple times so that the entire conductive connection portion 11 is dipped in the insulating adhesive 20A. At this time, the insulating adhesive 20A is also attached to a portion of each of the pair of extraction electrodes 12A, 12B. Further, at this time, a part of the cell stack 10 is moved so that the liquid level of the insulating adhesive 20A is in contact with the surface of the main body case 103 of each of the plurality of cells 100 facing in a direction perpendicular to the one direction D. It is immersed in the insulating adhesive 20A.

In the drying step S3, the insulating adhesive 20A attached to the cell laminate 10 in the dipping step S2 is dried. FIG. 5 is a schematic cross-sectional view showing a cell stack partially covered with an insulating member. As shown in FIG. 5, the insulating adhesive 20A is cured by drying and becomes an insulating member 20 which is a cured product of the insulating adhesive. As a result, a portion of the cell stack 10 is covered with the insulating member 20.

In the assembling step S4, the cell stack 10 partially covered with the insulating member 20 is assembled into the casing 30. At this time, the inside of the housing 30 is open to the outside. For example, when the housing 30 is composed of a box portion and a closing plate that closes the opening of the box portion, at least a portion of the closing plate does not close the opening of the box portion.

In the filling step S5, adhesive is filled between the casing 30 and the insulating member 20 in the direction orthogonal to the one direction D. The above-mentioned filling portion 40 is formed by the adhesive being cured.

In the sealing step S6, the casing 30 is sealed with the cell stack 10, the insulating member 20, and the filling part 40 located within the casing 30. Through the above steps, power storage module 1 according to an embodiment of the present disclosure is manufactured.

As described above, the power storage module 1 according to an embodiment of the present disclosure includes the cell stack 10 and one or more insulating members 20. The cell stack 10 has a plurality of cells 100 stacked in one direction D. Each of the plurality of cells 100 has a positive terminal 101 and a negative terminal 102. The positive electrode terminal 101 protrudes in a direction perpendicular to the one direction D mentioned above. The negative electrode terminal 102 protrudes in a direction perpendicular to the one direction D mentioned above. The cell stack 10 has a plurality of conductive connections 11. The conductive connection portion 11 is such that the positive electrode terminal 101 of one cell 100 among the plurality of cells 100 and the negative electrode terminal 102 of the cell adjacent to the one cell among the plurality of cells are electrically connected to each other in the one direction D. It is formed by being connected to. One or more insulating members 20 cover a portion of the cell stack 10. One or more insulating members 20 are made of a cured insulating adhesive and cover the plurality of conductive connections 11 .

According to the above configuration, the insulating member 20 can prevent electrical connection between the conductive connection parts 11 due to water generated by dew condensation, electrolyte leaked from the cell 100, or foreign matter mixed in from the outside. The insulation between the plurality of conductive connection parts 11 can be improved compared to the case where the conductive connection parts 11 are simply located apart from each other without using any other member between them.

The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

Reference Signs List 1 electricity storage module, 10 cell laminate, 100 cell, 101 positive electrode terminal, 102 negative electrode terminal, 103 main body case, 11 conductive connection part, 12A, 12B extraction electrode, 20 insulating member, 20A insulating adhesive, 30 housing, 40 Filling section.

Claims (1)

a cell stack having a plurality of cells stacked in one direction;
and one or more insulating members covering a portion of the cell stack,
Each of the plurality of cells is
a positive electrode terminal protruding in a direction perpendicular to the one direction;
a negative electrode terminal protruding in a direction perpendicular to the one direction;
In the cell stack, the positive electrode terminal in one of the plurality of cells and the negative electrode terminal in a cell adjacent to the one cell among the plurality of cells are electrically connected to each other in the one direction. It has a plurality of conductive connections formed by being connected,
An electricity storage module, wherein one or more of the insulating members are made of a cured insulating adhesive and cover the plurality of conductive connections.

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