US 12,261,292 B2
Positive electrode active material for lithium ion secondary battery and lithium ion secondary battery
Yuki Koshika, Niihama (JP); Haruki Kaneda, Niihama (JP); Sho Tsuruta, Kadoma (JP); Takashi Ko, Kadoma (JP); and Fumiharu Niina, Kadoma (JP)
Assigned to SUMITOMO METAL MINING CO., LTD., Tokyo (JP); and PANASONIC CORPORATION, Osaka (JP)
Appl. No. 17/625,850
Filed by SUMITOMO METAL MINING CO., LTD., Tokyo (JP); and PANASONIC CORPORATION, Kadoma (JP)
PCT Filed Jun. 30, 2020, PCT No. PCT/JP2020/025722
§ 371(c)(1), (2) Date May 17, 2022,
PCT Pub. No. WO2021/006124, PCT Pub. Date Jan. 14, 2021.
Claims priority of application No. 2019-127262 (JP), filed on Jul. 8, 2019.
Prior Publication US 2023/0187624 A1, Jun. 15, 2023
Int. Cl. H01M 4/505 (2010.01); C01G 53/44 (2025.01); H01M 4/131 (2010.01); H01M 4/525 (2010.01); H01M 10/0525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/505 (2013.01) [C01G 53/44 (2013.01); H01M 4/131 (2013.01); H01M 4/525 (2013.01); H01M 10/0525 (2013.01); C01P 2002/52 (2013.01); C01P 2002/85 (2013.01); C01P 2004/04 (2013.01); C01P 2004/50 (2013.01); C01P 2004/52 (2013.01); C01P 2004/61 (2013.01); C01P 2006/40 (2013.01); H01M 2004/028 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A positive electrode active material for a lithium ion secondary battery, the positive electrode active material comprising a lithium-nickel-manganese composite oxide having a hexagonal layered structure and configured by secondary particles with a plurality of aggregated primary particles,
wherein metal elements constituting the lithium-nickel-manganese composite oxide include lithium (Li), nickel (Ni), manganese (Mn), cobalt (Co), titanium (Ti), niobium (Nb), and optionally zirconium (Zr),
an amount of substance ratio of the metal elements is represented as Li:Ni:Mn:Co:Zr:Ti:Nb=a:b:c:d:e:f:g (provided that, 0.97≤a≤1.10, 0.80≤b≤0.88, 0.04≤c≤0.12, 0.04≤d≤0.10, 0≤e≤0.004, 0.003<f≤0.030, 0.001<g≤0.006, and b+c+d+e+f+g=1),
in the amount of substance ratio, (f+g)≤0.030 and f>g are satisfied,
niobium is segregated at a grain boundary between primary particles of the lithium-nickel-manganese composite oxide, and
an amount of lithium to be eluted in water when the positive electrode active material is immersed in water is 0.20% by mass or less with respect to the entire positive electrode active material.