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:
May. 18, 2021
Filed:
Oct. 02, 2015
Hitachi Metals, Ltd., Tokyo, JP;
Akira Gunji, Tokyo, JP;
Tatsuya Toyama, Tokyo, JP;
Shin Takahashi, Tokyo, JP;
Takashi Nakabayashi, Tokyo, JP;
Shuichi Takano, Tokyo, JP;
Xiaoliang Feng, Tokyo, JP;
Sho Furutsuki, Tokyo, JP;
Hisato Tokoro, Tokyo, JP;
HITACHI METALS, LTD., Tokyo, JP;
Abstract
A compound having a layered structure that is used for a positive electrode active material for a lithium ion secondary battery achieves both a high energy density and a high cyclability. The positive electrode active material for a lithium ion secondary battery contains a compound having a layered structure belonging to a space group R-3m, in which the compound having a layered structure is represented by a compositional formula: LiM1Owherein M1 represents a metal element or metal elements other than Li, and contains at least Ni, −0.03≤a≤0.10, and −0.1<α<0.1, a proportion of Ni in M1 is larger than 70 atom %, and a site occupancy of a transition metal or transition metals at a 3a site obtained by structural analysis by a Rietveld method is less than 2%, and a content of residual lithium hydroxide in the positive electrode active material is 1 mass % or less.