Power storage cell

Abstract

To provide a power storage cell that can reduce stress generated in an electrode body when the electrode body is swollen.SOLUTION: A power storage cell 1 includes: an electrode body 10 including a wound body formed by winding a positive electrode sheet 11 and a negative electrode sheet 12 through a separator 13, and tab leads 15, 16 protruding from end faces of the wound body; a cell case 20 housing the electrode body; an electrolyte filled in the cell case; and insulating plates 40, 50 bonded to the end faces of the wound body. The cell case includes: a cylindrical part 21a surrounding the electrode body; and a lid 22 connected to the cylindrical part. In the insulating plate, a plurality of holes h are formed. The plurality of holes h include tab lead holes h1 for inserting the tab leads.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a storage cell.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2007-200755 discloses a battery including a battery element formed of a wound body, a battery container that houses the battery element, and an insulating plate disposed on the battery element. The insulating plate is provided with a plurality of openings.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the battery described in Japanese Unexamined Patent Application Publication No. 2007-200755, a connecting member such as a tape is used to fix the end portion of the battery element formed of a wound body. Due to this connecting member, stress is generated in the battery element when the battery element expands.

[0005] An object of the present disclosure is to provide a storage cell capable of reducing stress generated in an electrode body when the electrode body expands.

Means for Solving the Problems

[0006] A power storage cell according to one aspect of the present disclosure includes an electrode body including a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween, and a tab lead protruding from an end surface of the wound body, a cell case that houses the electrode body, an electrolytic solution filled in the cell case, and an insulating plate made of an insulating material and adhered to the end surface of the wound body. The cell case includes a cylindrical portion that surrounds the electrode body and a lid connected to the cylindrical portion so as to close an opening of the cylindrical portion. A plurality of holes are formed in the insulating plate, and the plurality of holes include tab lead holes through which the tab leads are inserted.

Advantages of the Invention

[0007] According to the present disclosure, it is an object to provide a power storage cell capable of reducing stress generated in the electrode body during expansion of the electrode body.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Embodiments 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 partial cross-sectional view schematically showing a power storage cell according to an embodiment of the present disclosure. This power storage cell 1 is preferably mounted on a vehicle.

[0011] As shown in FIG. 1, the power storage cell 1 includes an electrode body 10, a cell case 20, a sealing member 30, a positive electrode side insulating plate 40, and a negative electrode side insulating plate 50. The positive electrode side insulating plate 40 and the negative electrode side insulating plate 50 correspond to the "insulating plate" in the present disclosure.

[0012] The electrode body 10 has a positive electrode sheet 11, a negative electrode sheet 12, a separator 13, a positive tab lead 15, and a negative tab lead 16. The positive tab lead 15 and the negative tab lead 16 correspond to the "tab lead" in the present disclosure.

[0013] The positive electrode sheet 11 has a positive electrode foil and a positive electrode active material layer provided on the positive electrode foil. The negative electrode sheet 12 has a negative electrode foil and a negative electrode active material layer provided on the negative electrode foil. The separator 13 is disposed between the positive electrode sheet 11 and the negative electrode sheet 12. The separator 130 is made of an insulating material and allows the permeation of ions. The positive electrode sheet 11, the negative electrode sheet 12, and the separator 13 constitute a wound body in which the positive electrode sheet 11 and the negative electrode sheet 12 are wound with the separator 13 in between.

[0014] The positive tab lead 15 is connected to the positive electrode sheet 11 of the wound body. The positive tab lead 15 protrudes upward from the upper end surface of the wound body.

[0015] The negative tab lead 16 is connected to the negative electrode sheet 12 of the wound body. The negative tab lead 16 protrudes downward from the lower end surface of the wound body.

[0016] The cell case 20 houses the electrode body 10. The cell case 20 also houses an electrolytic solution (not shown in the figure). The cell case 20 is sealed. The cell case 20 has a case body 21 and a lid 22.

[0017] The case body 21 is open upward. The case body 21 is made of a metal such as aluminum. The case body 21 has a cylindrical portion 21a and a bottom portion 21b.

[0018] The cylindrical portion 21a surrounds the electrode body 10. As shown in FIG. 2, on the inner peripheral surface of the cylindrical portion 21a, a groove a1 extending in a direction intersecting the circumferential direction of the wound body is formed. The groove a1 may extend parallel to the axial direction of the wound body, or may be formed in a spiral shape on the inner peripheral surface of the cylindrical portion 21a. Note that in FIG. 1, the illustration of the groove a1 is omitted.

[0019] The bottom portion 21b is formed in a disk shape. The bottom portion 21b is connected to the lower end portion of the cylindrical portion 21a. A negative electrode tab lead 16 is connected to the bottom portion 21b. Therefore, the case body 21 is charged with the same polarity as the negative electrode.

[0020] The lid 22 is connected to the cylindrical portion 21a so as to close the opening of the cylindrical portion 21a. As shown in FIG. 1, the lid 22 is connected to the upper end portion of the cylindrical portion 21a via a sealing member 30. A positive electrode tab lead 15 is connected to the lower surface of the lid 22. Therefore, the lid 22 is charged with the same polarity as the positive electrode.

[0021] The positive electrode side insulating plate 40 is made of an insulating material. The positive electrode side insulating plate 40 is formed in a disk shape. The positive electrode side insulating plate 40 is adhered to the upper end surface of the wound body by an adhesive member or the like. As shown in FIG. 2, a plurality of holes h are formed in the positive electrode side insulating plate 40. The plurality of holes h include a tab lead hole h1, an adjacent hole h2, and a groove hole h3.

[0022] The tab lead hole h1 is a through hole for inserting the positive electrode tab lead 15.

[0023] The adjacent hole h2 is formed at a position overlapping in the axial direction of the wound body with a portion adjacent to the positive electrode tab lead 15 in the circumferential direction of the wound body. That is, the adjacent hole h2 is formed at a position adjacent to the tab lead hole h1 in the circumferential direction. The adjacent hole h2 may be connected to the tab lead hole h1, or may be separated from the tab lead hole h1.

[0024] The groove hole h3 is a through hole for guiding the inflow of the electrolytic solution into the groove a1 of the cylindrical portion 21a. The groove hole h3 is formed at a position facing the groove a1. In the present embodiment, the groove hole h3 is constituted by a notch that opens toward the groove a1.

[0025] The negative electrode side insulating plate 50 is made of an insulating material. The negative electrode side insulating plate 50 is formed in a disc shape. The negative electrode side insulating plate 50 is adhered to the lower end surface of the wound body by an adhesive member or the like. As shown in FIG. 1, a through hole 50h for inserting the negative electrode tab lead 16 is formed in the negative electrode side insulating plate 50.

[0026] As described above, in the power storage cell 1 according to the present embodiment, since the positive electrode side insulating plate 40 is adhered to the upper end surface of the wound body and the negative electrode side insulating plate 50 is adhered to the lower end surface of the wound body, it is possible to omit a connecting member (such as a tape) for fixing the end portion of the wound body. Therefore, the stress generated in the electrode body 10 when the electrode body 10 expands is reduced.

[0027] Further, since a plurality of holes h are formed in the positive electrode side insulating plate 40, the flow of the electrolytic solution and gas is allowed while avoiding a short circuit caused by the contact between the upper end surface of the wound body and the lid 22.

[0028] Those skilled in the art will understand that the above-described exemplary embodiments are specific examples of the following aspects.

[0029] [Aspect 1] An electrode body including a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween, and a tab lead protruding from an end surface of the wound body. A cell case for housing the electrode body. An electrolytic solution filled in the cell case. An insulating plate made of an insulating material and adhered to the end surface of the wound body. The cell case A cylindrical portion surrounding the electrode body. A lid connected to the cylindrical portion so as to close an opening of the cylindrical portion. A plurality of holes are formed in the insulating plate. The plurality of holes include tab lead holes for inserting the tab lead, and the power storage cell.

[0030] In this power storage cell, since the insulating plate is adhered to the end face of the wound body, it is possible to omit a connecting member (such as a tape) for fixing the end portion of the wound body. Therefore, the stress generated in the electrode body during the expansion of the electrode body is reduced. In addition, since a plurality of holes are formed in the insulating plate, the flow of the electrolytic solution and gas is allowed while avoiding a short circuit caused by the contact between the end face of the wound body and the lid.

[0031] [Aspect 2] A groove extending in a direction intersecting the circumferential direction of the wound body is formed on the inner peripheral surface of the cylindrical portion. The plurality of holes include groove holes for guiding the inflow of the electrolytic solution into the groove, and the power storage cell according to Aspect 1.

[0032] In this aspect, since the electrolytic solution flows into the groove of the cylindrical portion through the groove holes of the insulating plate when the electrolytic solution is supplied, the liquid injection into the wound body becomes smooth.

[0033] [Aspect 3] The plurality of holes include adjacent holes formed at positions overlapping in the axial direction of the wound body with a portion adjacent to the tab lead in the circumferential direction of the wound body, and the power storage cell according to Aspect 1 or 2.

[0034] In this aspect, since the electrolytic solution flows into a portion adjacent to the tab lead in the circumferential direction of the wound body through the adjacent holes, the liquid injection into the wound body becomes smoother.

[0035] It should be considered that all the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present disclosure is shown not by the description of the above embodiments but by the scope of the claims, and further includes all changes within the meaning and scope equivalent to the scope of the claims.

Explanation of Reference Numerals

[0036] 1 Storage cell, 10 Electrode body, 11 Positive electrode sheet, 12 Negative electrode sheet, 13 Separator, 20 Cell case, 21 Case body, 21a Cylindrical part, 21b Bottom part, 22 Lid, 30 Sealing member, 40 Positive electrode side insulating plate, 50 Negative electrode side insulating plate, h Hole, h1 Tab lead hole, h2 Adjacent hole, h3 Groove hole.

Claims

1. An electrode body including a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween, and a tab lead protruding from an end surface of the wound body; A cell case that houses the electrode body; An electrolytic solution filled in the cell case; An insulating plate made of an insulating material and adhered to the end surface of the wound body; and The cell case includes: A cylindrical portion surrounding the electrode body; and A lid connected to the cylindrical portion so as to close an opening of the cylindrical portion, A plurality of holes are formed in the insulating plate, The plurality of holes include a tab lead hole through which the tab lead is inserted, a rechargeable cell.

2. A groove extending in a direction intersecting the circumferential direction of the wound body is formed on an inner peripheral surface of the cylindrical portion, The plurality of holes include a groove hole for guiding the inflow of the electrolytic solution into the groove, the rechargeable cell according to claim 1.

3. The plurality of holes include adjacent holes formed at a position overlapping in the axial direction of the wound body with a portion adjacent to the tab lead in the circumferential direction of the wound body among the wound bodies, the rechargeable cell according to claim 1.

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