US 12,444,752 B2
Lithium secondary battery
Hee Gyoung Kang, Daejeon (KR); Gi Hyeon Moon, Daejeon (KR); So Hyun Park, Daejeon (KR); Mi Ryeong Lee, Daejeon (KR); Jong Hyuk Lee, Daejeon (KR); Chan Young Jeon, Daejeon (KR); and Hae Suk Hwang, Daejeon (KR)
Assigned to SK ON CO., LTD., Seoul (KR)
Filed by SK ON CO., LTD., Seoul (KR)
Filed on Mar. 3, 2022, as Appl. No. 17/686,030.
Claims priority of application No. 10-2021-0028737 (KR), filed on Mar. 4, 2021.
Prior Publication US 2022/0285693 A1, Sep. 8, 2022
Int. Cl. H01M 4/70 (2006.01); H01M 4/02 (2006.01); H01M 4/13 (2010.01); H01M 10/0525 (2010.01); H01M 10/058 (2010.01); H01M 10/0585 (2010.01)
CPC H01M 4/70 (2013.01) [H01M 4/13 (2013.01); H01M 10/0525 (2013.01); H01M 10/0585 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A lithium secondary battery comprising:
a cathode including a cathode current collector including a cathode tab protruding from one end thereof, and a cathode active material layer formed on the cathode current collector; and
an anode disposed to face the cathode,
wherein the cathode active material layer comprises:
a first cathode portion disposed adjacent to the cathode tab in a planar direction; and
a second cathode portion spaced apart from the cathode tab with the first cathode portion interposed therebetween in the planar direction and having an electrode density lower than that of the first cathode portion,
wherein a cathode density difference defined by Formula 1 below is 1.5 to 6%:

OG Complex Work Unit Math
DdP is the cathode density difference, D1P is an electrode density of the first cathode portion, and D2P is an electrode density of the second cathode portion.