Effects of Pores in Surface-Coated Carbon Layer on Rate Performance of Graphite Cathode Materials
In order to study the effects of pores in surface-coated carbon layer on the rate performance of graphite cathode materials,a small amount of boric acid was added to generate gasification and effusion effect of boric acid during the softening stage of the coated asphalt.Then,a carbon layer with certain pores was formed on the surface of natural graphite tailings through carbonization,and graphite cathode materials with various proportions of pores were obtained.The results show that boric acid forms a carbon layer on the surface of particles containing mesoporous and macroporous pores.A higher proportion of mesopores in the surface carbon layer leads to more diffusion channels for Li+in the carbon layer LC,and lower diffusion impedance of Li+.In that case,the rate performance and cycling performance of the material are enhanced.