▎ 摘　　要

NOVELTY - Preparation of graphene-coated natural graphite cathode material involves (i) ultrasonically-dissolving a certain mass of graphene powder in a solvent to obtain graphene dispersions of different concentrations, (ii) fully and uniformly mixing natural graphite and graphene dispersions in a certain proportion to obtain a mixed solution, and (iii) passing the mixed solution into a spray dryer using a peristaltic pump and drying at a certain temperature and atomization frequency. USE - Preparation of graphene-coated natural graphite material used for preparing cathode for lithium ion battery used in electronic product and automobile electric vehicle. ADVANTAGE - The method uses liquid phase coating spray drying method, has simple preparation process, low cost, no pollution, suitable for mass production, uses graphene with flexible structure as coating agent, the natural graphite is coated to form a core-shell structure, the coating effect is good, has good compatibility with the electrolyte, avoids the stripping problem of the graphite layer caused by co-embedding of the solvated lithium ion, at the same time, and buffers the volume expansion of natural graphite electrode particles in the charging and discharging process. The method greatly improves the cycle performance of the lithium ion battery.