▎ 摘　　要

NOVELTY - Negative electrode material structure is a core-shell structure, in which nano-tin is a core and graphene is a shell. USE - Negative electrode material is used for lithium ion battery for energy storage. ADVANTAGE - The negative electrode material when used in the lithium ion battery for energy storage, the cycle performance, charge and discharge capacity of the lithium ion battery are optimized, and the advantages of large specific capacity of the tin-based material are fully retained. It also greatly improves the cycle stability of tin-based materials. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing lithium ion battery negative electrode material for energy storage, which involves mixing nano-tin, graphene oxide, and water uniformly and then performing a hydrothermal reaction to obtain a nano-tin/graphene oxide composite material, then freeze-drying, and then calcining in an inert atmosphere.