US 12,244,001 B2
Negative electrode for secondary battery and secondary battery including the same
Chan Young Jeon, Daejeon (KR); So Hyun Park, Daejeon (KR); Hae Suk Hwang, Daejeon (KR); and Hee Gyoung Kang, Daejeon (KR)
Assigned to SK On Co., Ltd., Seoul (KR)
Filed by SK On Co., Ltd., Seoul (KR)
Filed on Jan. 18, 2022, as Appl. No. 17/577,624.
Claims priority of application No. 10-2021-0007296 (KR), filed on Jan. 19, 2021.
Prior Publication US 2022/0231272 A1, Jul. 21, 2022
Int. Cl. H01M 4/133 (2010.01); H01M 4/587 (2010.01); H01M 10/0525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/133 (2013.01) [H01M 4/587 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A negative electrode for a secondary battery comprising:
a current collector; and
a negative electrode active material layer comprising a negative electrode active material, formed on the current collector,
wherein the negative electrode satisfies the following Relation 1:
3.0<τ*DP<7.2   [Relation 1]
wherein τ is a tortuosity of the negative electrode,
τ=(Rion×A×κ×ε)/d
wherein Rion is an ionic diffusion resistance (Ohm) by impedance analysis, A is an area of a negative electrode (cm2), κ is an ion conductivity (mS/cm) of an electrolyte solution, ε is a porosity of a negative electrode, and d is a thickness (μm) of a negative electrode, and
DP is a pellet density (g/cm3) of the negative electrode active material, measured by pressing the negative electrode active material at 8 kN/cm2.