▎ 摘　　要

NOVELTY - Graphene/silicon oxide-coated nano-silicon composite comprises nano-silicon matrix, silicon oxide coating layer coated on the surface of the nano-silicon substrate and the graphene coating layer coated on the surface of the silicon oxide coating layer. USE - The oxide-coated nano-silicon composite material of graphene/silicon is useful as cathode material for lithium ion battery (claimed). ADVANTAGE - The graphene/silicon oxide-coated nano-silicon composite material has higher specific capacity, rate performance and cycle stability. The method is simple and economical and has easy industrial production. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing graphene/silicon oxide-coated nano-silicon composite comprising providing silicon oxide-coated nano-silicon, mixing the silicon oxide-coated nano-silicon with an organic solvent to obtain a suspension, adding monolayer graphene aqueous solution of edge oxidation to suspension, obtaining oxide-coated nano-silicon composite material of edge-oxidized graphene/silicon through stirring, heating and drying, thermally treating the edge-oxidized graphene/silicon oxide-coated nano-silicon composite and obtaining graphene/silicon oxide-coated nano-silicon composite material. The preparation of silicon oxide-coated nano-silicon specifically includes mixing micro-silicon with organic solvent to obtain a mixed solution and preparing the silicon oxide-coated nano-silicon after the mixed solution is subjected to high-energy ball milling.