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. 16, 2003
Filed:
Jul. 10, 2001
Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi-gun, JP;
Abstract
A lithium secondary battery exhibiting very high safety, which is ensured by restraining both the generation of flammable gas caused by the decomposition of an electrolyte, and the emission of oxygen from a positive active material even during overcharging. The lithium secondary battery includes a positive electrode of which an active material is a lithium transition metal composite oxide, a negative electrode of which an active material is a carbon material, and a nonaqueous electrolyte containing an organic solvent in which a lithium salt is dissolved. The nonaqueous electrolyte contains at least one kind of conductive polymer-forming monomers which have an alkyl group and is electrochemically polymerizable on the positive electrode within a battery operation voltage, and at least one kind of film-forming agents which electrochemically decompose within the battery operation voltage to form films on a surface of the negative electrode.