Preparation method of high-cycle natural graphite negative electrode material

The invention discloses a preparation method of a high-cycle natural graphite negative electrode material. The high-cycle natural graphite negative electrode material is prepared by sequentially carrying out the steps of high-temperature oxidation, coating curing, isostatic pressing treatment, graphitization, carbonization and the like on natural graphite. Firstly, surface active points of the natural graphite can be removed through high-temperature oxidation treatment, the surface performance is improved, the reversible capacity is improved, meanwhile, a layer of hard carbon can be formed on the surface of the graphite through liquid-phase coating, small-particle natural graphite can be bonded into secondary particles, the defects of the surface of the graphite can be modified, the isotropy of the graphite can be improved, and in addition, the reversible capacity of the graphite can be improved. The isostatic pressing treatment can improve the compactness of the material, reduce the gaps of the internal stru