Negative electrode active material and preparation method thereof
AssigneeContemporary Amperex Technology (Hong Kong) Limited
InventorsBaida Deng, Meng Kang, Chen Zeng, Libing He
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Abstract
This application provides a negative electrode active material and a preparation method thereof. The negative electrode active material may be self-embedded graphite composed of graphite A and graphite B, where the surface of the graphite A may have a tenon structure, the surface of the graphite B may have a mortise structure, the tenon structure of the graphite A and the mortise structure of the graphite B may be mutually embedded, and a hydrogen bond may be formed between the tenon structure of the graphite A and the mortise structure of the graphite B.
Claims20
A negative electrode active material, wherein
- the negative electrode active material is self-embedded graphite composed of graphite A and graphite B;
- a surface of the graphite A has a tenon structure, and a surface of the graphite B has a mortise structure;
- and
- the tenon structure of the graphite A and the mortise structure of the graphite B are mutually embedded, and a hydrogen bond is formed between the tenon structure of the graphite A and the mortise structure of the graphite B.
A preparation method of negative electrode active material, comprising the following steps:
- (1) adding a first graphite matrix into a polar solvent, then adding a raw material for preparing an oxygen-containing metal salt to make an amount of the oxygen-containing metal salt coating a surface of the first graphite matrix be 1-5 wt % of a weight of the first graphite matrix, followed by stirring, evaporation, and drying, and then calcining the resulting mixture in a nitrogen atmosphere at a temperature of 500-1200° C. for 8-24 hours to obtain graphite A having a tenon structure;
- (2) adding a second graphite matrix into an alkaline solution having a pH greater than or equal to 13, stirring at a constant temperature of 60-100° C. for 8-36 hours, and after filtering, cleaning, and drying the resulting product to obtain graphite B having a mortise structure;
- and
- (3) mixing the graphite A and the graphite B to obtain a negative electrode active material.
Dependencies are inferred from the claim text.