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:
Jun. 08, 2004
Filed:
Apr. 25, 2001
Atsuo Yamada, Kanagawa, JP;
Takayuki Yamahira, Fukushima, JP;
Sony Corporation, Tokyo, JP;
Abstract
A lithium ion cell less costly than a control lithium ion cell is provided. The lithium ion cell is improved appreciably in operational stability under special conditions, such as high temperatures, and exhibits superior characteristics against over-discharging, while guaranteeing compatibility to the operating voltage of a conventional lithium ion cell and an energy density equivalent to that of the conventional lithium ion cell. To this end, the lithium ion cell includes a positive electrode, a negative electrode and a non-aqueous electrolyte, and uses, as a positive electrode active material, a composite material of a first lithium compound represented by the general formula Li M PO , where 0<x<2, 0.8<y<1.2 and M contains Fe, and a second lithium compound having a potential holder than the potential of the first lithium compound.