Power storage module

Abstract

To provide a power storage module capable of preventing formation of wrinkles on a laminate outer packaging.SOLUTION: A power storage module 1 comprises: an electrode body 10 including a plurality of electrodes laminated on each other; a laminate outer packaging 20 for housing the electrode body; and a spacer 30 which has a sealed interior space S and which is disposed between an end surface 10s of the electrode body and the laminate outer packaging. The spacer 30 comprises a material capable of expanding the interior space. The inner pressure of the laminate outer packaging is set so as to be lower than that of the spacer. The spacer expands so as to fill a portion between the end surface of the electrode body and the laminate outer packaging.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a power storage module.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2020-140874 discloses a laminated exterior battery including an electrode group including a plurality of electrodes laminated on each other, a laminated exterior body housing the electrode group, and a spacer disposed between the electrode group and the laminated exterior body. The laminated exterior body has a flange portion. The spacer is disposed between the flange portion and the electrode group. A corner portion between the outer surface and the upper surface of the spacer is curved.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the laminated exterior battery described in Japanese Unexamined Patent Application Publication No. 2020-140874, wrinkles may be formed at the corner portion of the boundary between the portion covering the outer surface of the spacer and the flange portion of the laminated exterior body.

[0005] An object of the present disclosure is to provide a power storage module capable of suppressing the formation of wrinkles on the laminated exterior body.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, a power storage module includes an electrode body including a plurality of electrodes stacked on one another, a laminate exterior body that houses the electrode body, and a spacer having a sealed internal space and disposed between an end face of the electrode body and the laminate exterior body. The spacer is made of a material capable of expanding the internal space, an internal pressure of the laminate exterior body is set lower than an internal pressure of the spacer, and the spacer is expanded so as to fill a space between the end face of the electrode body and the laminate exterior body.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a power storage module capable of suppressing the formation of wrinkles on the laminate exterior body.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0009] Embodiments of the present disclosure will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

[0010] FIG. 1 is a plan view schematically showing a power storage module in one embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II shown in FIG. 1. FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. 1.

[0011] As shown in FIGS. 1 to 3, the power storage module 1 includes an electrode body 10, a voltage detection terminal 15, a laminate exterior body 20, and a spacer 30.

[0012] The electrode body 10 has a plurality of electrodes (not shown) laminated on each other and a separator (not shown) disposed between the electrodes. Each electrode and the separator are formed in a rectangular shape. Therefore, the electrode body 10 is formed in a rectangular parallelepiped shape.

[0013] In the present embodiment, each electrode is composed of a bipolar electrode. The electrode body 10 has a pair of terminal electrodes 11 and 12 formed on the outermost side in the stacking direction of the plurality of electrodes (the vertical direction in FIGS. 2 and 3). One of the pair of terminal electrodes 11 and 12 is a positive electrode, and the other is a negative electrode.

[0014] The voltage detection terminal 15 detects the voltage of the electrode. For example, the voltage detection terminal 15 is connected to the central portion of the electrode body 10 in the stacking direction. The voltage detection terminal 15 is composed of a flexible printed circuit (FPC).

[0015] The laminate exterior body 20 houses the electrode body 10. The inside of the laminate exterior body 20 is sealed. The inside of the laminate exterior body 20 is filled with an electrolytic solution. The laminate exterior body 20 has a first film 21 and a second film 22. The inside of the laminate exterior body 20 is sealed by welding the edge 21a of the first film 21 and the edge 22a of the second film 22 to each other. The portion of the first film 21 facing the terminal electrode 11 is made of metal. Similarly, the portion of the second film 22 facing the terminal electrode 12 is made of metal.

[0016] As shown in FIGS. 1 and 3, the voltage detection terminal 15 protrudes from the edge of the laminate exterior body 20. As shown in FIG. 3, the voltage detection terminal 15 protrudes outside the laminate exterior body 20 from one side (the lower side in FIG. 3) in the stacking direction.

[0017] Note that tabs (uncoated portions of the current collector foil) formed at the edges of the respective electrodes in the electrode body 10 may be connected to the current collector plate, and a part of the current collector plate may be configured to protrude from the edge of the laminate exterior body 20.

[0018] The spacer 30 is disposed between the end face 10s of the electrode body 10 and the laminate exterior body 20. The end face 10s of the electrode body 10 means the outer surface of the electrode body 10 in a direction orthogonal to the stacking direction of the plurality of electrodes. The spacer 30 has a sealed internal space S. That is, the spacer 30 is formed in a hollow shape. In the present embodiment, the spacer 30 is formed in a shape that contacts one long side portion and one short side portion of the electrode body 10. However, the spacer 30 may be formed in an annular shape surrounding the electrode body 10. The spacer 30 is made of a material capable of expanding or contracting the internal space S. The spacer 30 is made of a material having electrolyte resistance. Examples of such materials include ethylene propylene diene rubber (EPDM) and butyl rubber.

[0019] As shown in FIGS. 2 and 3, when the internal pressure of the laminate exterior body 20 is lower than the internal pressure of the spacer 30, the spacer 30 expands so as to fill the space between the end face 10s of the electrode body 10 and the laminate exterior body 20.

[0020] Next, an example of the manufacturing method of the power storage module 1 will be described. For example, the electrode body 10 is disposed on the first film 21, and the spacer 30 filled with air under atmospheric pressure is disposed around the electrode body 10. Then, the electrode body 10 and the spacer 30 are covered with the second film 22. At this time, the electrode body 10 is placed in a state where it is shifted to one side of its long side portion and one side of its short side portion. The state at this time, that is, the state where the internal pressure of the laminate exterior body 20 and the internal pressure of the spacer 30 are equal to each other is shown in FIG. 4.

[0021] Thereafter, the inside of the laminate exterior body 20 is sealed by welding the edge portion 21a of the first film 21 and the edge portion 22a of the second film 22, and the inside of the laminate exterior body 20 is evacuated. Then, since the internal pressure of the laminate exterior body 20 becomes lower than the internal pressure of the spacer 30, the spacer 30 expands so as to fill the space between the end face 10s of the electrode body 10 and the laminate exterior body 20 as shown in FIGS. 2 and 3.

[0022] As described above, in the power storage module 1 according to the present embodiment, the internal pressure of the laminate exterior body 20 is set lower than the internal pressure of the spacer 30, and the spacer 30 expands so as to fill the space between the end face 10s of the electrode body 10 and the laminate exterior body 20. Therefore, the formation of wrinkles on the laminate exterior body 20 is suppressed.

[0023] Further, even when the electrode body 10 moves relative to the laminate exterior body 20, since the spacer 30 functions as a cushioning material, damage to the laminate exterior body 20 is suppressed.

[0024] As shown in FIG. 5, the voltage detection terminal 15 may be drawn out from the central portion of the electrode body 10 in the stacking direction to the outside of the laminate exterior body 20. In this case, the spacer 30 may have a first spacer portion 31 disposed on one side of the voltage detection terminal 15 in the stacking direction and a second spacer portion 32 disposed on the other side of the voltage detection terminal 15 in the stacking direction. Alternatively, in a region overlapping the voltage detection terminal 15 in the stacking direction, the spacer 30 may be omitted.

[0025] Those skilled in the art will understand that the above-described exemplary embodiments and examples are specific examples of the following aspects.

[0026] [Aspect 1] An electrode body including a plurality of electrodes stacked on one another, A laminate exterior body that houses the electrode body, A spacer having a sealed internal space and disposed between the end face of the electrode body and the laminate exterior body. The spacer is made of a material capable of expanding the internal space, the internal pressure of the laminated exterior body is set lower than the internal pressure of the spacer, the spacer expands to fill the space between the end face of the electrode body and the laminated exterior body, a power storage module.

[0027] In this power storage module, the internal pressure of the laminated exterior body is set lower than the internal pressure of the spacer, and the spacer expands to fill the space between the end face of the electrode body and the laminated exterior body, so that the formation of wrinkles on the laminated exterior body is suppressed.

[0028] [Aspect 2] the electrode body includes a voltage detection terminal for detecting the voltage of the electrode, the voltage detection terminal protrudes from the laminated exterior body, the spacer is a first spacer portion disposed on one side of the voltage detection terminal in the stacking direction of the plurality of electrodes, a second spacer portion disposed on the other side of the voltage detection terminal in the stacking direction, the power storage module according to aspect 1.

[0029] In this aspect, the formation of wrinkles in the portion of the laminated exterior body that overlaps the voltage detection terminal in the stacking direction is also effectively suppressed.

[0030] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present disclosure is shown by the claims rather than the description of the above embodiments, and further includes all changes within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0031] 1 Power storage module, 10 Electrode body, 10s End face, 15 Voltage detection terminal, 20 Laminated exterior body, 30 Spacer, 31 First spacer portion, 32 Second spacer portion, S Internal space.

Claims

1. An electrode body including a plurality of electrodes laminated on each other, A laminate exterior body housing the electrode body, A spacer having a sealed internal space and disposed between an end face of the electrode body and the laminate exterior body, The spacer is made of a material capable of expanding the internal space, The internal pressure of the laminate exterior body is set lower than the internal pressure of the spacer, The spacer expands to fill the space between the end face of the electrode body and the laminate exterior body. A power storage module.

2. The electrode body includes a voltage detection terminal for detecting the voltage of the electrode, The voltage detection terminal protrudes from the laminate exterior body, The spacer is A first spacer portion disposed on one side of the voltage detection terminal in the stacking direction of the plurality of electrodes, A second spacer portion disposed on the other side of the voltage detection terminal in the stacking direction. The power storage module according to claim 1.

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