US 11,942,635 B2
Positive electrode active material and lithium secondary battery comprising the same
Moon Ho Choi, Cheongju-si (KR); Jun Won Suh, Cheongju-si (KR); Jin Kyeong Yun, Cheongju-si (KR); Jung Han Lee, Cheongju-si (KR); Mi Hye Yun, Cheongju-si (KR); Seung Woo Choi, Cheongju-si (KR); Gwang Seok Choe, Cheongju-si (KR); Ye Ri Jang, Cheongju-si (KR); and Joong Ho Bae, Cheongju-si (KR)
Assigned to ECOPRO BM CO., LTD., Cheongju-si (KR)
Filed by ECOPRO BM CO., LTD., Cheongju-si (KR)
Filed on Sep. 28, 2020, as Appl. No. 17/035,672.
Claims priority of application No. 10-2019-0129755 (KR), filed on Oct. 18, 2019.
Prior Publication US 2021/0119205 A1, Apr. 22, 2021
Int. Cl. H01M 4/525 (2010.01); H01M 4/02 (2006.01); H01M 4/131 (2010.01); H01M 4/36 (2006.01); H01M 4/505 (2010.01); H01M 10/0525 (2010.01)
CPC H01M 4/525 (2013.01) [H01M 4/131 (2013.01); H01M 4/366 (2013.01); H01M 4/505 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01); Y02E 60/10 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A positive electrode active material, comprising:
primary particles enabling lithium intercalation and deintercalation;
a secondary particle formed by aggregating the primary particles; and
a coating layer,
wherein the coating layer covers at least a part of an interface between the primary particles, or at least a part of the surface of the secondary particle, or both at least the part of the interface between the primary particles and at least the part of the surface of the secondary particle,
wherein the secondary particle has a first concentration gradient section in which the concentration of at least one selected from nickel, cobalt and manganese in the secondary particle increases, and a second concentration gradient section in which the concentration of at least one selected from nickel, cobalt and manganese in the secondary particle decreases,
wherein the first concentration gradient section and the second concentration gradient section are laterally arranged along the circumferential surface of the secondary particle, and
wherein the concentration of the first concentration gradient section and the concentration of the second concentration gradient section are not due to the coating layer.