US 12,255,327 B2
Positive electrode active material, method of preparing the positive electrode active material, and positive electrode and lithium secondary battery which include the positive electrode active material
Dong Hun Lee, Daejeon (KR); Sung Bin Park, Daejeon (KR); Hyung Man Cho, Daejeon (KR); Jung Min Han, Daejeon (KR); Jin Tae Hwang, Daejeon (KR); and Wang Mo Jung, Daejeon (KR)
Assigned to LG Energy Solution, Ltd., Seoul (KR)
Appl. No. 17/413,100
Filed by LG Chem, Ltd., Seoul (KR)
PCT Filed Jan. 7, 2020, PCT No. PCT/KR2020/000297
§ 371(c)(1), (2) Date Jun. 11, 2021,
PCT Pub. No. WO2020/145639, PCT Pub. Date Jul. 16, 2020.
Claims priority of application No. 10-2019-0001843 (KR), filed on Jan. 7, 2019.
Prior Publication US 2022/0013775 A1, Jan. 13, 2022
Int. Cl. H01M 4/525 (2010.01); H01M 4/04 (2006.01); H01M 4/505 (2010.01); H01M 10/0525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/525 (2013.01) [H01M 4/0471 (2013.01); H01M 4/505 (2013.01); H01M 10/0525 (2013.01); H01M 2004/028 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A positive electrode active material comprising:
a nickel-based lithium transition metal oxide containing nickel in an amount of 60 mol % or more based on a total number of moles of metals excluding lithium; and
a cobalt,
wherein the cobalt is included in an amount of 2,000 ppm to 5,000 ppm relative to a total weight of the positive electrode active material, in a surface portion of the nickel-based lithium transition metal oxide,
wherein the nickel-based lithium transition metal oxide is represented by Formula 1:
Li1+a[NixMnyM1z]O2  [Formula 1]
wherein, in Formula 1,
M1 is, 0≤a≤0.3, 0.60≤x<1, 0<y≤0.40, and 0≤z≤0.35, and
wherein at least one of the nickel or manganese has a concentration gradient from a surface of a positive electrode active material particle, and wherein the amount of the nickel or the manganese is increased in a direction toward a center of the positive electrode active material particle.