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:
Dec. 25, 2012
Filed:
Aug. 05, 2010
Masao Shimizu, Hitachi, JP;
Yoshiaki Kumashiro, Kasama, JP;
Masao Shimizu, Hitachi, JP;
Yoshiaki Kumashiro, Kasama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A nonaqueous lithium secondary battery includes a positive electrode and a negative electrode capable of intercalating and releasing lithium ions and a separator. The negative electrode includes a collector and a negative electrode mixture layer formed on the collector. The negative electrode mixture layer includes at least a negative electrode active material and a binder. Nonconductive particles are buried in a top layer of the negative electrode mixture layer. The nonconductive particles and the negative electrode active material exist as a mixture in the top layer with a depth ranging from 1 to 20 μm. A volume ratio of nonconductive particles having a diameter equal to or less than 20 μm to a total volume of all the nonconductive particles and the negative electrode active material existing in the top layer of the negative electrode mixture layer ranges from 20 to 80%.