GRAPHITE NEGATIVE ELECTRODE MATERIAL FOR HIGH-PERFORMANCE LITHIUM ION BATTERY AND PREPARATION METHOD THEREFOR

摘要

Disclosed is a graphite negative electrode material for a high-performance lithium ion battery and a preparation method therefor. The preparation process therefor comprises the following steps: 1) subjecting natural graphite to a surface oxidation treatment; 2) coating the natural graphite, which has undergone the oxidation treatment, with hard carbon to obtain a precursor; 3) subjecting the precursor obtained in step 2) to a carbonization treatment; 4) subjecting the precursor, which has undergone the carbonization treatment, to an impregnation treatment; and 5) crushing the impregnated material, and then carbonizing same to obtain a high-capacity high-power graphite negative electrode material. The surface oxidation treatment increases the capacity of the natural graphite, the coating with the hard carbon endows same with a large rate charging capacity, and the impregnation treatment can repair any defects remaining after the oxidation and hard carbon coating, thereby improving the cycle performance thereof.