According to Baidu Library, the sphericity of graphite refers to the similarity between the shape of graphite particles and spheres, which reflects the molding effect and electrochemical performance of graphite particles. The higher the sphericity of graphite, it means that the closer graphite particles are to the sphere, the better its tap density, specific surface area, cycle stability and specific capacity. There are many formulas for calculating graphite sphericity, one of which is based on the ratio of volume to surface area, that is, S=6V/Sp. Where s is that sphericity of graphite, v is the volume of graphite particle, sp? Is the surface area of graphite particles. The principle of this formula is to compare graphite particles with spheres of the same volume. If graphite particles are completely spherical, its surface area is equal to that of a sphere with the same volume.