▎ 摘　　要

NOVELTY - Preparing carbon-coated core-shell structure nano-silicon/graphene composite cathode material comprises e.g. taking nano-silica or silicate as silicon source, preparing nano-silica dispersion or silicate solution by cationic surfactant modification, mixing with graphene oxide sol, self-assembly by electrostatic nano-silica or silicate graphene oxide layer adsorbed evenly to obtain a silica/graphene composite or a silicate/graphene oxide composite, drying silica/graphene oxide composite or silicate/graphene oxide composite material into a molten salt under nitrogen atmosphere. USE - The method is useful for preparing carbon-coated core-shell structure nano-silicon/graphene composite cathode material. ADVANTAGE - The material has simple preparation process, high efficiency of coulomb and excellent cycle performance. DETAILED DESCRIPTION - Preparing carbon-coated core-shell structure nano-silicon/graphene composite cathode material comprises (i) taking nano-silica or silicate as silicon source, preparing nano-silica dispersion or silicate solution by cationic surfactant modification, mixing with graphene oxide sol, self-assembly by electrostatic nano-silica or silicate graphene oxide layer adsorbed evenly to obtain a silica/graphene composite or a silicate/graphene oxide composite, (ii) drying silica/graphene oxide composite or silicate/graphene oxide composite material into a molten salt under nitrogen atmosphere and carrying out situ reduction at low temperature to obtain nano-silicon/graphene composite material, and (iii) taking reduced nano-silicon/graphene composite material and a certain amount of graphite and carbon source material composite coating in the sphere of equipment, carbonizing under inert atmosphere to obtain final product. An INDEPENDENT CLAIM is also included for carbon-coated core-shell structure nano-silicon/graphene composite cathode material is obtained by above mentioned method.