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:
Mar. 25, 2025
Filed:
Feb. 26, 2020
Sumitomo Metal Mining Co., Ltd., Tokyo, JP;
Takahiro Toma, Ehime, JP;
Takahiro Ogawa, Ehime, JP;
Yoshiyuki Matsuura, Ehime, JP;
Kazuomi Ryoshi, Ehime, JP;
SUMITOMO METAL MINING CO., LTD., Tokyo, JP;
Panasonic Energy Co., Ltd., Osaka, JP;
Abstract
A positive electrode active material for a lithium ion secondary battery contains a lithium metal composite oxide. The lithium metal composite oxide includes lithium (Li), nickel (Ni), cobalt (Co), and element M (M) in a mass ratio of Li:Ni:Co:M=1+a:1−x−y:x:y (wherein −0.05≤a≤0.50, 0≤x≤0.35, 0≤y≤0.35, and the element M is at least one element selected from Mg, Ca, Al, Si, Fe, Cr, Mn, V, Mo, W, Nb, Ti, Zr, and Ta), wherein when a line analysis is performed with STEM-EELS from a surface of a particle of the lithium metal composite oxide to a center of the particle in a cross-section of the particle during charging at 4.3 V (vs. Li/Li), a thickness of an oxygen release layer, in which an intensity ratio of a peak near 530 eV (1st) to a peak near 545 eV (2nd) at an O-K edge is 0.9 or less, is 200 nm or less.