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:
Aug. 06, 2019
Filed:
Apr. 13, 2012
Ryuichi Kasahara, Tokyo, JP;
Jiro Iriyama, Tokyo, JP;
Shin Serizawa, Tokyo, JP;
Hiroo Takahashi, Tokyo, JP;
Tatsuji Numata, Tokyo, JP;
Ryuichi Kasahara, Tokyo, JP;
Jiro Iriyama, Tokyo, JP;
Shin Serizawa, Tokyo, JP;
Hiroo Takahashi, Tokyo, JP;
Tatsuji Numata, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
The object of an exemplary embodiment of the invention is to provide a lithium ion secondary battery having an excellent charge and discharge cycle property. An exemplary embodiment of the invention is a lithium ion secondary battery, comprising a battery assembly in which a positive electrode and a negative electrode are stacked through a separator and a package in which the battery assembly and an electrolyte are placed; wherein the negative electrode comprises a negative electrode collector which is composed of a metal and a negative electrode active material layer which is formed on the negative electrode collector and which comprises a negative electrode active material and a binder; wherein the negative electrode collector and the negative electrode active material layer have a crack which is formed so as to be communicated with each of them; and wherein the crack reaches an outer peripheral edge from an inside of the negative electrode.