BATTERY AND MANUFACTURING METHOD OF THE BATTERY

• US 20130316209A1
• Filed: 12/20/2011
• Published: 11/28/2013
• Est. Priority Date: 02/16/2011
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Masumoto, Kenjin, Kakinuma, Akira, Yoneda, Keisuke, Nishimori, Junya
• Granted Patent: US 10,658,633 B2
• Time in Patent Office: Days
• US Class Current: 429/94
• CPC Class Codes: H01M 10/0422 Cells or battery with cylindrical casing
• CPC Class Codes: H01M 10/0431 Cells with wound or folded electrodes H01M10/045 takes precedence
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/742 perforated material
• CPC Class Codes: H01M 50/103 prismatic or rectangular H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/107 having curved cross-section, e.g. round or elliptic H01M50/103, H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/184 characterised by their shape or structure
• CPC Class Codes: H01M 50/186 characterised by the disposition of the sealing members
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/4911 including sealing

Abstract

A battery includes a first electrode plate, a second electrode plate, a separator interposed between the first and second electrode plates, a closed-end cylindrical metal case accommodating these three elements, and a sealing member sealing an opening of the metal case with an insulating member interposed therebetween. The first and second electrode plates are wound with the separator interposed therebetween to form a wound electrode group. A center axis portion of the wound electrode group is substantially the same as a center axis of a cylinder of the metal case, and contains no power-generating element. A first current collector lead coupled to the first electrode plate extends toward the opening of the metal case, and joined to an inner sidewall surface of the metal case. A second current collector lead coupled to the second electrode plate extends toward the opening of the metal case, and joined to the sealing member.

Claims

1. A battery, comprising:

a first electrode plate;

a second electrode plate having polarity opposite to that of the first electrode plate;

a separator interposed between the first and second electrode plates;

a closed-end cylindrical metal case configured to accommodate the first electrode plate, the second electrode plate, and the separator; and

a sealing member configured to seal an opening of the metal case with an insulating member interposed therebetween, wherein

the first and second electrode plates are wound with the separator interposed therebetween to form a wound electrode group,

a center axis portion of the wound electrode group includes a center axis of a cylinder of the metal case, and contains no power-generating element,

the metal case is a first electrode terminal, and the sealing member is a second electrode terminal,

a first current collector lead electrically coupled to the first electrode plate extends toward the opening of the metal case, and joined to an inner sidewall surface of the metal case, and

a second current collector lead electrically coupled to the second electrode plate extends toward the opening of the metal case, and joined to the sealing member.

2. The battery of claim 1, wherein

a length of the first current collector lead in a circumferential direction of the wound electrode group ranges from 10% to 30%, both inclusive, of a length of an outer periphery of the wound electrode group.

3. The battery of claim 1, wherein

the first current collector lead is made of metal foil with a thickness of 50 μ

m or less.

4. The battery of claim 1, wherein

in the center axis portion of the wound electrode group, a portion without any power-generating element has a diameter of 3.0 mm or less.

5. The battery of claim 4, wherein

the portion without any power-generating element has a diameter less than 1.5 mm.

6. The battery of claim 4, wherein

the center axis portion of the wound electrode group is hollow.

7. The battery of claim 1, wherein

the first current collector lead curves in a same direction as the inner sidewall surface of the metal case, and

the first current collector lead is joined to the inner sidewall surface of the metal case such that a center of a radius of curvature of the first current collector lead is located inside the metal case.

8. The battery of claim 3, wherein

a groove extending in a direction orthogonal to the circumferential direction of the wound electrode group is formed in the first current collector lead.

9. The battery of claim 3, wherein

a plurality of holes are open in the metal foil forming the first current collector lead.

10. The battery of claim 9, wherein

the holes are arranged in a honeycomb pattern.

11. A manufacturing method of a battery comprising:

a step of attaching a first current collector lead to a first electrode plate;

a step of attaching a second current collector lead to a second electrode plate having polarity opposite to that of the first electrode plate;

a step of fabricating a wound electrode group by winding the first electrode plate and the second electrode plate around a winding core member with a separator interposed between the first and second electrode plates;

a step of accommodating the wound electrode group in a closed-end cylindrical metal case being a first electrode terminal;

a step X of joining the first current collector lead to an inner sidewall surface of the metal case;

a step of joining the second current collector lead to a sealing member being a second electrode terminal; and

a step of sealing the metal case by disposing an insulating member at an inner-surface side of an opening of the metal case, inserting the sealing member in a position of the opening in which the insulating member is disposed, and crimping the metal case to the sealing member, wherein

before the step X, a joint portion of the first current collector lead with the inner sidewall surface of the metal case is curved in a same direction as a curve of the inner sidewall surface of the metal case.

12. A manufacturing method of a battery comprising:

a step of attaching a first current collector lead to a first electrode plate;

a step of attaching a second current collector lead to a second electrode plate having polarity opposite to that of the first electrode plate;

a step of fabricating a wound electrode group by winding the first electrode plate and the second electrode plate around a winding core member with a separator interposed between the first and second electrode plates;

a step of accommodating the wound electrode group in a closed-end cylindrical metal case being a first electrode terminal;

a step X of joining the first current collector lead to an inner sidewall surface of the metal case;

a step of joining the second current collector lead to a sealing member being a second electrode terminal; and

a step of sealing the metal case by disposing an insulating member at an inner-surface side of an opening of the metal case, inserting the sealing member in a position of the opening in which the insulating member is disposed, and crimping the metal case around the sealing member, wherein

in the step X of joining, a joint portion of the first current collector lead with the inner sidewall surface of the metal case is curved in a same direction as a curve of the inner sidewall surface of the metal case.