Power storage device

Abstract

To provide a power storage device in which both the protection of a sealing member to seal a liquid injection port and the suppression of displacement between conductive plates can be achieved.SOLUTION: A power storage device 1 includes an electrode body 12, a holding part 14 to hold the edge of the electrode body, a sealing part 20 to seal a liquid injection port formed in the holding part, a protection member 40 to protect the sealing part, and a pair of conductive plates 30 disposed in contact with the electrode body from both sides of the electrode body in a layer stacking direction. The sealing part 20 projects from the holding part in an orthogonal direction that is orthogonal to the layer stacking direction. The protection member 40 includes a covering part 42 that covers the sealing part with a space from the sealing part in the orthogonal direction, a first connection part 44 that connects the covering part and the conductive plate disposed on one side of the covering part in the layer stacking direction, and a second connection part 46 that connects the covering part and the conductive plate disposed on the other side of the covering part in the layer stacking direction.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2023-80893 discloses a power storage module including a plurality of bipolar cells stacked on each other and a sealing member that seals a liquid injection port formed in the bipolar cell. The liquid injection member of each cell protrudes in a direction orthogonal to the stacking direction.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a power storage module as described in Japanese Unexamined Patent Application Publication No. 2023-80893, there is a concern that components constituting the power storage device may come into contact with the sealing member due to vibration or the like. Further, when conductive plates such as current collector plates are stacked on both sides of the power storage module, there is a concern that the conductive plates may be displaced relative to each other.

[0005] An object of the present disclosure is to provide a power storage device capable of achieving both protection of a sealing member that seals a liquid injection port and suppression of displacement between conductive plates.

Means for Solving the Problems

[0006] A power storage device according to an aspect of the present disclosure includes an electrode body including a plurality of electrodes laminated on each other, a holding portion that holds an edge portion of the electrode body, a sealing portion that seals a liquid injection port formed in the holding portion, a protective member that protects the sealing portion, and a pair of conductive plates disposed so as to contact the electrode body from both sides of the electrode body in the stacking direction of the plurality of electrodes. The sealing portion protrudes from the holding portion in a direction orthogonal to the stacking direction, and the protective member includes a covering portion that covers the sealing portion with a gap from the sealing portion in the orthogonal direction, a first connecting portion that connects the conductive plate disposed on one side of the covering portion in the stacking direction and the covering portion, and a second connecting portion that connects the conductive plate disposed on the other side of the covering portion in the stacking direction and the covering portion.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a power storage device capable of achieving both protection of a sealing member that seals a liquid injection port and suppression of displacement between conductive plates.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode 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 perspective view schematically showing a part of an energy storage device according to an embodiment of the present disclosure. FIG. 2 is a perspective view of a protective member. FIG. 3 is a cross-sectional view schematically showing the energy storage device.

[0011] As shown in FIGS. 1 to 3, the energy storage device 1 includes at least one energy storage module 10, a sealing portion 20, a pair of conductive plates 30, and a protective member 40.

[0012] At least one energy storage module 10 includes a plurality of energy storage modules 10. In the present embodiment, as shown in FIG. 3, the energy storage device 1 has four energy storage modules 10. However, the number of energy storage modules 10 is not limited to four. The energy storage module 10 has an electrode body 12 and a holding portion 14.

[0013] The electrode body 12 has a plurality of electrodes (not shown) laminated on each other and a plurality of separators (not shown). The outer shape of the electrode body 12 in plan view is formed in a quadrangular shape. The plurality of electrodes have terminal electrodes disposed on the outermost side in the stacking direction of the plurality of electrodes and a plurality of bipolar electrodes disposed between the respective terminal electrodes. However, each electrode may be composed of a monopolar electrode (not shown).

[0014] The holding portion 14 holds the edge portion of the electrode body 12. The holding portion 14 is formed in a rectangular tubular shape surrounding the periphery of the electrode body 12. The holding portion 14 is made of an insulating material. The holding portion 14 is preferably made of a synthetic resin (such as polyethylene or polypropylene). The holding portion 14 seals the edge portion of the electrode body 12. The holding portion 14 has a function of preventing leakage of the electrolytic solution from the electrode body 12 and intrusion of moisture from the outside into the electrode body 12, and a function of ensuring the interval between the respective electrodes.

[0015] As shown in FIG. 3, a plurality of liquid injection ports 14a for supplying the electrolytic solution to the electrode body 12 are formed in the holding portion 14. The plurality of liquid injection ports 14a are provided at intervals in the longitudinal direction (the direction perpendicular to the paper surface in FIG. 3) of one of the four side portions of the holding portion 14.

[0016] The sealing portion 20 seals the liquid injection port 14a. The sealing portion 20 protrudes from the holding portion 14 in a direction orthogonal to the stacking direction. The outer shape of the sealing portion 20 is formed in a substantially rectangular parallelepiped shape.

[0017] A pair of conductive plates 30 are arranged to contact the electrode body 12 from both sides of the electrode body 12 in the stacking direction. In the present embodiment, each conductive plate 30 also contacts the holding portion 14. That is, the pair of conductive plates 30 are in contact with the power storage module 10 from both sides of the power storage module 10 in the stacking direction. Each conductive plate 30 is formed in a flat plate shape. As shown in FIG. 1, each conductive plate 30 has a plurality of through holes h.

[0018] The conductive plate 30 is composed of a cooling plate or a current collecting plate. The cooling plate cools the power storage module 10 by a refrigerant (such as water or air) flowing through the cooling plate. The conductive plates 30 arranged on the outermost sides (the lowermost surface and the uppermost surface) in the stacking direction are composed of current collecting plates that contact the terminal electrodes of the electrode body 12. For example, the conductive plate 30 arranged between the lowermost power storage module 10 and the power storage module 10 stacked thereon, and the conductive plate 30 arranged between the uppermost power storage module 10 and the power storage module 10 adjacent thereto below may be composed of cooling plates. The conductive plate 30 arranged between the second power storage module 10 from the bottom and the second power storage module 10 from the top may be composed of a current collecting plate.

[0019] The protective member 40 protects the sealing portion 20. The protective member 40 is preferably made of a synthetic resin having electrolyte resistance. The protective member 40 has a covering portion 42, a first connecting portion 44, a second connecting portion 46, and a pair of clamping portions 48.

[0020] The covering portion 42 covers the sealing portion 20 with a space therebetween in the orthogonal direction. That is, as shown in FIG. 3, a space S is formed between the outer surface of the sealing portion 20 and the covering portion 42. The covering portion 42 is formed in a flat plate shape. As shown in FIG. 3, the length of the covering portion 42 in the stacking direction is the same as the length of the electrode body 12 in the stacking direction.

[0021] The first connecting portion 44 connects the conductive plate 30 disposed on one side (e.g., the lower side) of the covering portion 42 in the stacking direction and the covering portion 42. The first connecting portion 44 protrudes from the covering portion 42 toward one side in the stacking direction. As shown in FIG. 2, the first connecting portion 44 protrudes from the central portion of the covering portion 42 in a direction orthogonal to both the thickness direction and the up-and-down direction of the covering portion 42.

[0022] The second connecting portion 46 connects the conductive plate 30 disposed on the other side (e.g., the upper side) of the covering portion 42 in the stacking direction and the covering portion 42. The second connecting portion 46 protrudes from the covering portion 42 toward the other side in the stacking direction. As shown in FIG. 2, the second connecting portion 46 protrudes from both end portions of the covering portion 42 in a direction orthogonal to both the thickness direction and the up-and-down direction of the covering portion 42. The second connecting portion 46 is provided at a position that does not overlap with the first connecting portion 44 in the up-and-down direction.

[0023] Each through hole h formed in the conductive plate 30 has a shape for receiving each of the first connecting portion 44 and the second connecting portion 46. The first connecting portion 44 and the second connecting portion 46 are inserted into the respective through holes h. As shown in FIG. 3, the length of the first connecting portion 44 in the stacking direction is the same as the thickness of the conductive plate 30. Also, the length of the second connecting portion 46 in the stacking direction is the same as the thickness of the conductive plate 30.

[0024] A pair of clamping portions 48 clamp the sealing portion 20 from both sides in the stacking direction. Each clamping portion 48 has an arm portion 48a and a gripping portion 48b.

[0025] The wrist portion 48a extends from the inner surface of the covering portion 42 in the orthogonal direction toward the power storage module 10. The length of the wrist portion 48a in the orthogonal direction is greater than the length of the sealing portion 20 in the orthogonal direction. The wrist portion 48a includes a contact portion 48c that contacts the sealing portion 20. The contact portion 48c is constituted by the inner end surface of the wrist portion 48a in the orthogonal direction. The contact portion 48c is formed flat.

[0026] The gripping portion 48b protrudes from the inner end of the wrist portion 48a in the orthogonal direction toward the sealing portion 20. The gripping portion 48b is in contact with the end surface of the sealing portion 20 in the stacking direction. The gripping portion 48b extends in a direction orthogonal to both the thickness direction and the vertical direction of the covering portion 42. The length between the pair of gripping portions 48b in the stacking direction is set to be approximately the same as or slightly smaller than the length of the sealing portion 20 in the stacking direction. That is, the sealing portion 20 is press-fitted between the pair of gripping portions 48b.

[0027] Next, an example of the manufacturing method of the power storage device 1 will be described. For example, the first conductive plate 30 is placed on a flat mounting table, and the protection member 40 is attached to each sealing portion 20. Then, the first connecting portion 44 of the protection member 40 is inserted into the through hole h of the first conductive plate 30. Next, the second conductive plate 30 is stacked on the power storage module 10 so that the second connecting portion 46 of each protection member 40 is inserted into the through hole h of the second conductive plate 30. By repeating the above steps, the power storage device 1 is manufactured.

[0028] As described above, in the power storage device 1 according to the present embodiment, since the covering portion 42 covers the sealing portion 20 with a gap therebetween, the sealing portion 20 is effectively protected even when an external load is input to the covering portion 42, and since the pair of conductive plates 30 are connected by the connecting portions 44 and 46, displacement between the conductive plates 30 is suppressed.

[0029] As shown in FIGS. 4 and 5, the power storage device 1 may further include rail portions 25 provided on each side portion of the holding portion 14 where the liquid injection port 14a is not formed, and a plurality of connecting members 50 that can be attached to each rail portion 25. The rail portion 25 has a shape extending along the longitudinal direction of the side portion where the rail portion 25 is provided. The configuration of the connecting member 50 corresponds to the configuration of the protection member 40. The conductive plate 30 has through holes h for receiving the first connecting portion 54 and the second connecting portion 56 of each connecting member 50.

[0030] Those skilled in the art will understand that the above-described exemplary embodiments and examples are specific examples of the following aspects.

[0031] [Aspect 1] An electrode body including a plurality of electrodes laminated on each other, A holding portion that holds an edge portion of the electrode body, A sealing portion that seals a liquid injection port formed in the holding portion, A protection member that protects the sealing portion, A pair of conductive plates arranged to contact the electrode body from both sides of the electrode body in the stacking direction of the plurality of electrodes, and The sealing portion protrudes from the holding portion in a direction orthogonal to the stacking direction, The protection member, A covering portion that covers the sealing portion at an interval from the sealing portion in the orthogonal direction, A first connecting portion that connects the conductive plate disposed on one side of the covering portion in the stacking direction and the covering portion, A second connecting portion that connects the conductive plate disposed on the other side of the covering portion in the stacking direction and the covering portion, and has a power storage device.

[0032] In this power storage device, since the covering portion covers the sealing portion at an interval from the sealing portion, the sealing portion is effectively protected even when an external load is input to the covering portion, and since the pair of conductive plates are connected by the respective connecting portions, displacement between the conductive plates is suppressed.

[0033] [Aspect 2] The power storage device according to Aspect 1, wherein the protective member further has a pair of clamping portions that clamp the sealing portion from both sides in the stacking direction.

[0034] In this aspect, relative displacement of the electrode body with respect to each conductive plate is suppressed.

[0035] [Aspect 3] The power storage device according to Aspect 2, wherein each of the pair of clamping portions includes a contact portion that contacts the holding portion.

[0036] In this aspect, when a load is input in the direction from the protective member toward the electrode body, each clamping portion supports the load between the holding portion and the covering portion, so that contact of the covering portion with the sealing portion and breakage of the sealing portion resulting therefrom are effectively suppressed.

[0037] [Aspect 4] The power storage device according to Aspect 1, wherein a length of the covering portion in the stacking direction is the same as a length of the electrode body in the stacking direction.

[0038] In this aspect, the covering portion can receive a load in the stacking direction acting on a portion outside the electrode body in a direction orthogonal to the stacking direction among the conductive plates.

[0039] [Aspect 5] Each of the conductive plates has a through hole for receiving the first connecting portion and the second connecting portion, The power storage device according to Aspect 4, wherein a length of the first connecting portion in the stacking direction and a length of the second connecting portion in the stacking direction are the same as a thickness of each of the conductive plates.

[0040] In this aspect, since the total thickness of the electrode body and the pair of conductive plates is the same as the total length of each connecting portion and the covering portion in the stacking direction, stacking of a plurality of electrode bodies and conductive plates becomes easy.

[0041] 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 invention is shown by the scope of claims rather than the description of the above embodiments, and further includes all changes within the meaning and scope equivalent to the scope of claims.

Explanation of Reference Numerals

[0042] 1 Power storage device, 10 Power storage module, 12 Electrode body, 14 Holding part, 14a Liquid injection port, 20 Sealing part, 25 Rail part, 30 Conductive plate, 40 Protection member, 42 Coating part, 44 First connecting part, 46 Second connecting part, 48 Clamping part, 48a Arm part, 48b Gripping part, 48c Contact part, h Through hole, S Space.

Claims

1. An electrode body including a plurality of electrodes laminated on one another, a holding portion that holds an edge portion of the electrode body, a sealing portion that seals a liquid injection port formed in the holding portion, a protective member that protects the sealing portion, and a pair of conductive plates arranged to contact the electrode body from both sides of the electrode body in the lamination direction of the plurality of electrodes. The sealing portion protrudes from the holding portion in a direction orthogonal to the lamination direction. The protective member has a covering portion that covers the sealing portion with a gap in the orthogonal direction, a first connecting portion that connects the conductive plate arranged on one side of the covering portion in the lamination direction and the covering portion, and a second connecting portion that connects the conductive plate arranged on the other side of the covering portion in the lamination direction and the covering portion. The power storage device.

2. The power storage device according to claim 1, wherein the protective member further has a pair of sandwiching portions that sandwich the sealing portion from both sides in the lamination direction.

3. The power storage device according to claim 2, wherein each of the pair of sandwiching portions includes a contact portion that contacts the holding portion.

4. The power storage device according to claim 1, wherein a length of the covering portion in the lamination direction is the same as a length of the electrode body in the lamination direction.

5. Each of the conductive plates has a through hole that receives the first connecting portion and the second connecting portion. The power storage device according to claim 4, wherein a length of the first connecting portion in the lamination direction and a length of the second connecting portion in the lamination direction are the same as a thickness of each of the conductive plates.

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