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:
Jan. 28, 2014
Filed:
Mar. 12, 2010
Hirokazu Nomura, Kyoto, JP;
Akira Yamashita, Kyoto, JP;
Fusaji Kita, Kyoto, JP;
Hitachi Maxell, Ltd., Ibaraki-shi, JP;
Abstract
The electrochemical device of the present invention comprises a positive electrode (), a negative electrode (), a nonaqueous electrolyte and a separator (). The separator () includes a porous layer (I) composed of a microporous film composed predominantly of a thermoplastic resin and a porous layer (II) containing a filler having a heat-resistant temperature of 150° C. or higher as the main component. The negative electrode () contains graphite having an R value of 0.1 to 0.5 and dof 0.338 nm or less as a negative electrode active material, where the R value is a ratio of a peak intensity at 1360 cmto a peak intensity at 1580 cmin an argon ion laser Raman spectrum and the dis a lattice spacing between 002 planes. The ratio of the graphite to the negative electrode active material is 30 mass % or more, and the nonaqueous electrolyte contains vinyl ethylene carbonate or a derivative thereof, or a dinitrile compound or acid anhydride.