Electrochemical Element

• US 20080206635A1
• Filed: 02/25/2008
• Published: 08/28/2008
• Est. Priority Date: 02/27/2007
• Status: Active Grant

• Current Assignee: Seiko Instruments Incorporated (Seiko Group)
• Original Assignee: Seiko Instruments Incorporated (Seiko Group)
• Inventors: Watanabe, Shunji, Onodera, Hideharu, Sato, Ryo
• Granted Patent: US 8,916,289 B2
• Time in Patent Office: Days
• US Class Current: 429/185
• CPC Class Codes: H01M 50/109 of button or coin shape
• CPC Class Codes: H01M 50/176 for prismatic or rectangular cells H01M50/181 takes precedence
• CPC Class Codes: H01M 50/184 characterised by their shape or structure
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

An electrochemical element comprises a container and a sealing plate for sealing an opening of the container. The container is sealed with the sealing plate by welding a portion of the brazing material on the sealing plate and a portion of the metal film of the container which make contact with each other together in a state where a first electrode active material, a separator, a second electrode active material and an electrolyte are contained in the container. An electricity collector sheet is electrically connected to the first electrode active material or the second electrode active material, whichever is closer to the opening of the container. At least a portion of the electricity collector sheet extends to the end portion of the container so that the container and the sealing plate are welded together with the extending portion of the electricity collector sheet in between. Thus, the manufacturing process may be simplified so that the welding of the container and the sealing plate can be easily carried out even when the container and the sealing plate are reduced in size.

Claims

1. An electrochemical element, comprising:

a container having an end portion and an outer surface, where the end portion defines an opening, a metal film is formed on the end portion, a pair of external terminals are formed on the outer surface and the metal film is electrically connected to one of the pair of external terminals;

a sealing plate for sealing an opening of the container, where a brazing material is placed on the sealing plate, and the container is sealed with the sealing plate by welding a portion of the brazing material on the sealing plate and a portion of the metal film of the container which make contact with each other together in a state where a first electrode active material, a separator, a second electrode active material and an electrolyte are contained in the container; and

an electricity collector sheet, which is electrically connected to the first electrode active material or the second electrode active material, whichever is closer to the opening of the container, where at least a portion of the electricity collector sheet extends to the end portion of the container so that the container and the sealing plate are welded together with the extending portion of the electricity collector sheet in between.

2. The electrochemical element according to claim 1, wherein the electricity collector sheet is made of nickel.

3. The electrochemical element according to claim 1, wherein a concave is formed in the upper surface of the sealing plate, and a convex to be engaged with the opening of the container is formed on the lower surface of the sealing plate.

4. The electrochemical element according to claim 1, wherein the container is made of alumina and the metal film and the sealing plate are made of Kovar.

5. The electrochemical element according to claim 3, wherein a brazing material, which is made of nickel plating, is placed on the surface of the sealing plate which faces the container, the metal film of the container is a metal ring made of Kovar, and a brazing material made of a nickel and gold plating is placed on top of the metal ring.

6. The electrochemical element according to claim 1, wherein the first electrode active material, the separator and the second electrode active material are layered on top of each other, and the multilayer body is contained in the container without being folded.

7. The electrochemical element according to claim 1, wherein the first electrode active material, the separator and the second electrode active material are layered on top of each other, the electricity collector sheet is a first electricity collector, the electrochemical element further comprises a second electricity collector sheet which is electrically connected to an electrode active material that is different from the electrode active material to which the first electricity collector is electrically connected, and the multilayer body is folded in such a manner that the first electricity collector and second electricity collector appear on the sides of the container facing each other when being contained in the container.

8. The electrochemical element according to claim 1, wherein the container has four side walls, the end portion corresponds to upper end portions of the four side walls and the extending portion of the electricity collector sheet reaches an upper end portion of the four side walls.