US 11,862,793 B2
Positive electrode active material for non-aqueous electrolyte secondary battery and method for producing the same, and non-aqueous electrolyte secondary battery and method for producing the same
Kazuomi Ryoshi, Niihama (JP); Motoaki Saruwatari, Niihama (JP); Hiroko Oshita, Niihama (JP); and Yoshihiro Otsuka, Niihama (JP)
Assigned to SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
Appl. No. 16/641,864
Filed by SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
PCT Filed Aug. 23, 2018, PCT No. PCT/JP2018/031246
§ 371(c)(1), (2) Date May 6, 2020,
PCT Pub. No. WO2019/039566, PCT Pub. Date Feb. 28, 2019.
Claims priority of application No. 2017-162661 (JP), filed on Aug. 25, 2017.
Prior Publication US 2020/0313180 A1, Oct. 1, 2020
Int. Cl. H01M 4/525 (2010.01); H01M 4/131 (2010.01); H01M 4/1391 (2010.01); H01M 4/505 (2010.01); H01M 10/0525 (2010.01); H01M 50/46 (2021.01); H01M 4/02 (2006.01)
CPC H01M 4/525 (2013.01) [H01M 4/131 (2013.01); H01M 4/1391 (2013.01); H01M 4/505 (2013.01); H01M 10/0525 (2013.01); H01M 50/46 (2021.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A method for producing a positive electrode active material for a non-aqueous electrolyte secondary battery, comprising a lithium-nickel composite oxide represented by general formula (1): LiaNi1−x−yCoxMyO2+α (in which 0.05≤x≤0.35, 0≤y≤0.10, 0.95≤a≤1.10, 0≤α≤0.2, and M represents at least one element selected from Mn, V, Mg, Mo, Nb, Ti, W, and Al) and Li3BO3, the method comprising:
mixing a boron compound, at least one of a nickel composite hydroxide and a nickel composite oxide, and a lithium compound to obtain a lithium mixture; and
firing the lithium mixture in an oxygen atmosphere at a temperature of 715° C. or higher and 850° C. or lower to obtain a lithium-nickel composite oxide, wherein
the boron compound is mixed in an amount such that the content of boron is 0.001% by mass or more and 0.2% by mass or less with respect to the entire positive electrode active material, and
at least a part of a surface of the obtained lithium-nickel composite oxide is coated with Li3BO3,
a diffraction peak of Li3BO3 is only detected as a diffraction peak other than that derived from the lithium-nickel composite oxide in powder X-ray diffraction, and
the method is conducted without a step of reducing the content of boron from the lithium-nickel complex oxide such that the content of boron from the lithium mixture is maintained in the entire lithium-nickel complex oxide produced by the method.