Patent ID: 11961993
Assignee: CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A secondary battery, comprising a negative electrode plate, a positive electrode plate, a separator, and an electrolyte, wherein the electrolyte comprises an organic solvent and an electrolyte salt, the negative electrode plate comprises a negative current collector and negative film layers, wherein the negative film layers comprise a first negative film layer and a second negative film layer, the first negative film layer is disposed on at least one surface of the negative current collector and comprises a first negative active material, and the second negative film layer is disposed on the first negative film layer and comprises a second negative active material;
the first negative active material comprises natural graphite, and the second negative active material comprises artificial graphite;
the first negative active material has a powder orientation index (OI) value COI1 satisfying 4.7≤COI1≤5.0; and
the second negative active material has a powder orientation index (OI) value COI2 satisfying 2.8≤COI2≤3.0, and
the first negative active material and the second negative active material further satisfy 1.1≤COI1/COI2≤2.5,
wherein
COI1 is a ratio of peak area of 004 characteristic diffraction peak to peak area of 110 characteristic diffraction peak in an X-ray diffraction pattern of the first negative active material; and
COI2 is a ratio of peak area of 004 characteristic diffraction peak to peak area of 110 characteristic diffraction peak in an X-ray diffraction pattern of the second negative active material; and
wherein the first negative active material has a particle diameter distribution satisfying 0.8≤(DV90−DV10)/DV50≤1.5, and the second negative active material has a particle diameter distribution satisfying 0.9≤(DV90−DV10)/DV50≤2.