US 12,334,557 B2
Negative-electrode active material and preparation method thereof, secondary battery, and battery module, battery pack, and apparatus containing such secondary battery
Yuqun Zeng, Ningde (CN); Baida Deng, Ningde (CN); Meng Kang, Ningde (CN); Erling Li, Ningde (CN); and Libing He, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed on Jul. 10, 2023, as Appl. No. 18/349,219.
Application 18/349,219 is a division of application No. 17/822,260, filed on Aug. 25, 2022, granted, now 12,218,354.
Application 18/349,219 is a division of application No. PCT/CN2020/121268, filed on Oct. 15, 2020.
Prior Publication US 2023/0369591 A1, Nov. 16, 2023
Int. Cl. H01M 4/583 (2010.01); H01M 4/02 (2006.01); H01M 4/04 (2006.01); H01M 4/62 (2006.01)
CPC H01M 4/583 (2013.01) [H01M 4/0471 (2013.01); H01M 4/622 (2013.01); H01M 4/625 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A negative-electrode active material, comprising granulated artificial graphite particles having an amorphous carbon coating layer covering at least part of surfaces of the granulated artificial graphite particles, wherein
Dv10, a particle size corresponding to a cumulative volume distribution percentage reaching 10%, of the negative-electrode active material is 6 μm-8 μm;
Dv50, a particle size corresponding to cumulative volume distribution percentage reaching 50%, of the negative-electrode active material is 11 μm-13 μm;
Dv90, a particle size corresponding to cumulative volume distribution percentage reaching 90%, of the negative-electrode active material is 14 μm-17 μm;
Dv99, a particle size corresponding to cumulative volume distribution percentage reaching 99%, of the negative-electrode active material is 18 μm-21 μm;
a particle size uniformity of the negative-electrode active material is 0.32-0.38; and
a particle size specific surface area of the negative-electrode active material is 0.4 m2/g-0.75 m2/g;
wherein the negative-electrode active material is prepared by a method that comprises:
preparing a core material, wherein the core material comprises the granulated artificial graphite particles;
mixing the core material with an organic carbon source; and
heat treating the mixed core material at 700-1800° C., to form the negative-electrode active material;
wherein after the heat treatment, 70%-95% of the particles of the negative-electrode active material are agglomerated.