The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2003
Filed:
Apr. 10, 2000
Yusuke Watarai, Omiya, JP;
Akio Minakuchi, Omiya, JP;
Tadashi Kobayashi, Omiya, JP;
Akihiro Higami, Omiya, JP;
Sawako Takeuchi, Omiya, JP;
Mitsubishi Materials Corporation, Tokyo, JP;
Abstract
A lithium ion polymer secondary battery is a laminate of a positive-electrode sheet of a positive-electrode collector foil provided with an active material thereon, a negative-electrode sheet of a negative-electrode collector foil provided with another active material thereon, and a polymer electrolyte layer interposed between the positive-electrode sheet and the negative-electrode sheet. One of the positive-electrode sheet and the negative-electrode sheet is a strip and is fan-folded at least one time so that the positive-electrode sheet is provided on the surface of the active material on the sheet. The other one of the positive-electrode sheet and the negative-electrode sheet consists of a plurality of sheet segments having an area which is the same as the area of each flat portion of the fan-folded sheet. The sheet segments are interposed between the flat portions of the fan-folded sheet so that the polymer electrolyte layer is in contact with the surfaces of the active materials. The battery exhibits a large discharge capacity and improved discharge capacity characteristics after a number of discharge-charge cycles and does not cause internal short-circuiting.