US 12,406,981 B2
Negative electrode for lithium secondary battery and lithium secondary battery comprising same
Taek Soo Lee, Daejeon (KR); Jin Ho Cho, Daejeon (KR); Jong Su Yoon, Daejeon (KR); Shin Wook Jeon, Daejeon (KR); and Young Gon Kim, Daejeon (KR)
Assigned to LG Energy Solution, Ltd., Seoul (KR)
Appl. No. 18/730,216
Filed by LG Energy Solution, Ltd., Seoul (KR)
PCT Filed Sep. 15, 2023, PCT No. PCT/KR2023/013861
§ 371(c)(1), (2) Date Jul. 18, 2024,
PCT Pub. No. WO2024/058584, PCT Pub. Date Mar. 21, 2024.
Claims priority of application No. 10-2022-0116873 (KR), filed on Sep. 16, 2022; and application No. 10-2023-0062304 (KR), filed on May 15, 2023.
Prior Publication US 2025/0105253 A1, Mar. 27, 2025
Int. Cl. H01M 4/133 (2010.01); H01M 10/052 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/133 (2013.01) [H01M 10/052 (2013.01); H01M 2004/027 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A negative electrode for a lithium secondary battery, comprising:
a negative electrode current collector, and
a negative electrode active layer arranged on at least one side of the negative electrode current collector and including a carbon-based negative electrode active material;
wherein the negative electrode active layer is divided into a flat portion having a constant thickness relative to a cross-sectional structure of the negative electrode active layer, and a sliding portion disposed at an end of the flat portion and having a thickness gradient;
wherein the flat portion and the sliding portion have ratios of 98.5% to 99.9% and 0.1 to 1.5% of a total length in a width direction, respectively, based on the cross-sectional structure of the negative electrode active layer;
wherein the sliding portion has a value of 1.0 or less according to Equation 1 when analyzed by near-end X-ray absorption fine structure (NEXAFS) spectroscopy, and an alignment (O.I) of the carbon-based negative electrode active material of 0.1 to 0.6 according to Equation 4 when analyzed by X-ray diffraction (XRD) spectroscopy, and wherein the alignment (O.I) of the carbon-based negative electrode active material contained in the flat portion has a ratio of 110% to 200% based on the alignment of the carbon-based negative electrode active material contained in the sliding portion:

OG Complex Work Unit Math
wherein, in Equation 1 to Equation 4,
S60/0 represents a value of a ratio of a ratio of a peak intensity (I60B/A) at an incidence angle of 60° of the X-ray to a ratio of a peak intensity (I0B/A) at an incidence angle of 0° of the X-ray,
I60A represents an intensity of a strongest peak present at 286±1.0 eV, at the incidence angle of 60°,
I60B represents an intensity of a strongest-peak present at 292.5±1.0 eV at the incidence angle of 60°,
I0A represents an intensity of a strongest peak at 286±1.0 eV at the incidence angle of 0°,
I0B represents an intensity of a strongest peak present at 292.5±1.0 eV at the incidence angle of 0°,
I004 represents an area of a peak representing a (0,0,4) crystal face, and
I110 represents an area of a peak representing a (1,1,0) crystal face.