US 12,249,710 B2
Positive electrode active material for lithium ion secondary battery and lithium ion secondary battery
Yuki Koshika, Niihama (JP); and Haruki Kaneda, Niihama (JP)
Assigned to PANASONIC ENERGY CO., LTD., Osaka (JP); and SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
Appl. No. 17/625,871
Filed by SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
PCT Filed Jun. 30, 2020, PCT No. PCT/JP2020/025732
§ 371(c)(1), (2) Date Jan. 10, 2022,
PCT Pub. No. WO2021/006129, PCT Pub. Date Jan. 14, 2021.
Claims priority of application No. 2019-127260 (JP), filed on Jul. 8, 2019; and application No. 2020-100828 (JP), filed on Jun. 10, 2020.
Prior Publication US 2022/0278322 A1, Sep. 1, 2022
Int. Cl. H01M 4/525 (2010.01); H01M 4/38 (2006.01); H01M 4/505 (2010.01); H01M 10/0525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/525 (2013.01) [H01M 4/386 (2013.01); H01M 4/505 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01)] 12 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 composite oxide having a hexagonal layered structure and configured by secondary particles with a plurality of aggregated primary particles,
wherein the lithium-nickel composite oxide contains lithium (Li), nickel (Ni), manganese (Mn), titanium (Ti), niobium (Nb), and optionally an element M1 that is at least one element selected from the group consisting of Co, V, Mg, Mo, Ca, Cr, Ta, Na, W, Fe, Zn, B, Si, P, Zr, and Al,
an amount of substance ratio of the respective elements is represented as Li:Ni:Mn:M1:Ti:Nb=a:(1−x1−y1−b−c):x1:y1:b:c (provided that, 0.95≤ a≤1.25, (1−x1−y1−b−c)<0.80, 0.03≤x1≤0.35, 0≤y1≤0.35, 0.005≤b≤0.05,and 0.001<c≤0.03),
in the amount of substance ratio, (b+c)≤0.06 and b>c are satisfied,
the niobium is detected in a concentrated state at a grain boundary between primary particles, and
an amount of lithium to be eluted in water when the positive electrode active material is immersed in water is 0.07% by mass or less with respect to the entire positive electrode active material.