Energy 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] This 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 top of 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 Documents

Patent Documents

[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. Also, 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 misaligned with respect to each other.

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

Means for Solving the Problems

[0006] A power storage device according to one aspect of the present disclosure comprises an electrode body including a plurality of electrodes stacked on top of each other, a holding portion for holding the edges of the electrode body, a sealing portion for sealing a liquid injection port formed in the holding portion, a protective member for protecting the sealing portion, and a pair of conductive plates arranged to be in contact with the electrode body from both sides of the electrode body in the stacking direction of the plurality of electrodes, wherein the sealing portion protrudes from the holding portion in an orthogonal direction perpendicular to the stacking direction, and the protective member has a covering portion that covers the sealing portion at a distance from the sealing portion in the orthogonal direction, a first connecting portion that connects the conductive plate and the covering portion, which is located on one side of the covering portion in the stacking direction, and a second connecting portion that connects the conductive plate and the covering portion, which is located on the other side of the covering portion in the stacking direction. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide an energy storage device that can achieve both protection of the sealing member that seals the liquid injection port and suppression of misalignment between conductive plates. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic perspective view showing a part of an energy storage device in one embodiment of the present disclosure. [Figure 2] This is a perspective view of the protective component. [Figure 3] This is a schematic cross-sectional view of an energy storage device. [Figure 4] This is a perspective view illustrating a schematic variation of an energy storage module. [Figure 5] This is a schematic cross-sectional view showing a modified example of an energy storage device. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described with reference to the drawings. In the drawings referred to below, the same or equivalent components are given the same number.

[0010] Figure 1 is a schematic perspective view showing a part of an energy storage device in one embodiment of the present disclosure. Figure 2 is a perspective view of a protective member. Figure 3 is a schematic cross-sectional view showing the energy storage device.

[0011] As shown in Figures 1 to 3, the energy storage device 1 comprises 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 multiple energy storage modules 10. In this embodiment, as shown in Figure 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. Each energy storage module 10 includes an electrode body 12 and a holding portion 14.

[0013] The electrode body 12 has multiple electrodes (not shown) stacked on top of each other and multiple separators (not shown). In plan view, the outer shape of the electrode body 12 is formed as a rectangle. Each of the multiple electrodes has a terminal electrode located on the outermost side in the stacking direction of the multiple electrodes and a multiple bipolar electrode located between each terminal electrode. However, each electrode may be composed of a monopolar electrode (not shown).

[0014] The holding portion 14 holds the edge of the electrode body 12. The holding portion 14 is formed in a rectangular tubular shape that surrounds the electrode body 12. The holding portion 14 is made of an insulating material. Preferably, the holding portion 14 is made of a synthetic resin (polyethylene, polypropylene, etc.). The holding portion 14 seals the edge of the electrode body 12. The holding portion 14 has the function of preventing electrolyte leakage from the electrode body 12 and moisture from entering the electrode body 12 from the outside, and also has the function of ensuring the spacing between each electrode.

[0015] As shown in Figure 3, the holding portion 14 has a plurality of injection ports 14a for supplying electrolyte to the electrode body 12. The plurality of injection ports 14a are spaced apart in the longitudinal direction of one of the four sides of the holding portion 14 (in the direction perpendicular to the plane of the paper in Figure 3).

[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, a pair of conductive plates 30 contact 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 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 sandwiching portions 48.

[0020] The covering portion 42 covers the sealing portion 20 with a gap 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 (for example, 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 the direction orthogonal to both the thickness direction and the vertical direction of the covering portion 42.

[0022] The second connecting portion 46 connects the conductive plate 30 disposed on the other side (for example, 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 the direction orthogonal to both the thickness direction and the vertical 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 vertical direction.

[0023] Each through hole h formed in the conductive plate 30 has a shape that receives 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] The pair of sandwiching portions 48 sandwich the sealing portion 20 from both sides in the stacking direction. Each sandwiching portion 48 has an arm portion 48a and a gripping portion 48b.

[0025] The arm portion 48a extends from the inner surface of the covering portion 42 in the orthogonal direction toward the energy storage module 10. The length of the arm portion 48a in the orthogonal direction is greater than the length of the sealing portion 20 in the orthogonal direction. The arm portion 48a includes a contact portion 48c that abuts against the sealing portion 20. The contact portion 48c is formed on the inner end face of the arm portion 48a in the orthogonal direction. The contact portion 48c is formed flat.

[0026] The gripping portion 48b protrudes toward the sealing portion 20 from the inner end of the arm portion 48a in the perpendicular direction. The gripping portion 48b is in contact with the end face of the sealing portion 20 in the stacking direction. The gripping portion 48b extends in a direction perpendicular 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 the same as or slightly less than the length of the sealing portion 20 in the stacking direction. In other words, the sealing portion 20 is press-fitted between the pair of gripping portions 48b.

[0027] Next, an example of a manufacturing method for the energy storage device 1 will be described. For example, the first conductive plate 30 is placed on a flat mounting base, and protective members 40 are attached to each sealing portion 20. The first connecting portion 44 of the protective member 40 is then inserted into the through hole h of the first conductive plate 30. Next, a second conductive plate 30 is stacked on the energy storage module 10 so that the second connecting portion 46 of each protective member 40 is inserted into the through hole h of the second conductive plate 30. The energy storage device 1 is manufactured by repeating the above process.

[0028] As described above, in the energy storage device 1 of this embodiment, the covering portion 42 covers the sealing portion 20 at a distance from the sealing portion 20, so that the sealing portion 20 is effectively protected even when an external load is applied to the covering portion 42, and the pair of conductive plates 30 are connected to each other by the connecting portions 44 and 46, so that misalignment between the conductive plates 30 is suppressed.

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

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

[0031] [Aspect 1] An electrode body comprising multiple electrodes stacked on top of each other, A holding portion that holds the edge of the electrode body, A sealing portion that seals the liquid injection port formed in the holding portion, A protective member that protects the sealing portion, The plurality of electrodes comprises a pair of conductive plates arranged to be in contact with the electrode body from both sides of the electrode body in the stacking direction of the electrode body, The sealing portion protrudes from the holding portion in a direction perpendicular to the stacking direction, The protective member is A covering portion that covers the sealing portion at a distance from the sealing portion in the orthogonal direction, A first connecting portion that connects the conductive plate and the covering portion, which are arranged on one side of the covering portion in the stacking direction, A power storage device having a second connecting portion that connects the conductive plate, which is located on the other side of the covering portion in the stacking direction, to the covering portion.

[0032] In this energy storage device, the covering portion covers the sealing portion at a distance from the sealing portion, so that the sealing portion is effectively protected even when an external load is applied to the covering portion, and because the pair of conductive plates are connected by each connecting portion, displacement between the conductive plates is suppressed.

[0033] [Aspect 2] The energy storage device according to embodiment 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 embodiment, the relative displacement of the electrode body with respect to each conductive plate is suppressed.

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

[0036] In this embodiment, when a load is applied 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, thereby effectively suppressing contact between the covering portion and the sealing portion and the resulting damage to the sealing portion.

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

[0038] In this embodiment, the load acting in the stacking direction on the outer portion of the electrode body in a direction perpendicular to the stacking direction of the conductive plate can be received by the covering portion.

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

[0040] In this embodiment, the sum of the thicknesses of the electrode body and the pair of conductive plates is equal to the sum of the lengths of each connecting portion and covering portion in the stacking direction, making it easy to stack multiple electrode bodies and conductive plates.

[0041] It should be noted that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments above, and further includes all modifications within the meaning and scope equivalent to the claims. [Explanation of Symbols]

[0042] 1 Energy storage device, 10 Energy storage module, 12 Electrode body, 14 Holding part, 14a Liquid injection port, 20 Sealing part, 25 Rail part, 30 Conductive plate, 40 Protective member, 42 Covering 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 comprising multiple electrodes stacked on top of each other, A holding portion that holds the edge of the electrode body, A sealing portion that seals the liquid injection port formed in the holding portion, A protective member that protects the sealing portion, The plurality of electrodes comprises a pair of conductive plates arranged to be in contact with the electrode body from both sides of the electrode body in the stacking direction of the electrode body, The sealing portion protrudes from the holding portion in a direction perpendicular to the stacking direction, The protective member is A covering portion that covers the sealing portion at a distance from the sealing portion in the orthogonal direction, A first connecting portion that connects the conductive plate and the covering portion, which are arranged on one side of the covering portion in the stacking direction, A power storage device having a second connecting portion that connects the conductive plate, which is located on the other side of the covering portion in the stacking direction, to the covering portion.

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

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

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

5. Each of the conductive plates has through holes for receiving the first connecting portion and the second connecting portion. The energy storage device according to claim 4, wherein the length of the first connecting portion in the stacking direction and the length of the second connecting portion in the stacking direction are the same as the thickness of each conductive plate.

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