US 12,095,092 B2
Electrode for secondary battery and method for preparing the same
Hyun Joong Jang, Daejeon (KR); Min Hwan Kim, Daejeon (KR); Sung Jun Park, Daejeon (KR); and Byoung Wook Jo, Daejeon (KR)
Assigned to SK On Co., Ltd., Seoul (KR)
Filed by SK On Co., Ltd., Seoul (KR)
Filed on Aug. 17, 2021, as Appl. No. 17/403,948.
Claims priority of application No. 10-2020-0103327 (KR), filed on Aug. 18, 2020.
Prior Publication US 2022/0059844 A1, Feb. 24, 2022
Int. Cl. H01M 4/62 (2006.01); H01M 4/04 (2006.01); H01M 4/139 (2010.01); H01M 10/0525 (2010.01)
CPC H01M 4/622 (2013.01) [H01M 4/0404 (2013.01); H01M 4/139 (2013.01); H01M 10/0525 (2013.01)] 4 Claims
 
1. An electrode for a secondary battery, comprising:
an electrode current collector; and
an electrode mixture layer formed on at least one surface of the electrode current collector,
wherein based on a region corresponding to 50% of a thickness of the electrode mixture layer in a direction in which the electrode mixture layer is formed from a surface of the electrode current collector, a ratio (B/A) of cohesive force (A) between an electrode active material and a binder or between adjacent binders included in a lower region, and cohesive force (B) between an electrode active material and a binder or between adjacent binders included in an upper region is less than 1.5,
wherein, based on the direction in which the electrode mixture layer is formed from the surface of the electrode current collector, the lower region is a region corresponding to a thickness of 15% or less of the electrode mixture layer, excluding 0%, from the surface of the electrode current collector based on a total thickness of the electrode mixture layer,
wherein the upper region is a region corresponding to a thickness of 85 to 100% of the electrode mixture layer from the surface of the electrode current collector based on a total thickness of the electrode mixture layer, and
wherein the binder or at least one of the adjacent binders included in the electrode mixture layer comprises styrene butadiene rubber (SBR).