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:
Feb. 05, 2002
Filed:
Jul. 13, 1998
Applicant:
Inventors:
Assignee:
NGK Insulators, Ltd., , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01M 2/12 ; H01M 1/040 ;
U.S. Cl.
CPC ...
H01M 2/12 ; H01M 1/040 ;
Abstract
A lithium secondary battery includes a battery case, and an internal electrode body contained in the battery case and including a positive electrode and a negative electrode wound through a separator film made of porous polymer, and uses a nonaqueous organic electrolyte. Opposing pressure release mechanisms are disposed at both ends of the battery case in the winding direction of the positive electrode and the negative electrode. The lithium secondary battery is simple in fabrication, has small internal resistance, and is superior in safety. Preferably, the ratio of the total area of opening portions where the pressure release mechanisms operate to the battery capacity is kept within a predefined range.