▎ 摘　　要

NOVELTY - A graphene nanomaterial composite comprises 10-20 pts. wt. modified graphene oxide, 20-30 pts. wt. carboxymethyl chitosan, and 5-12 pts. wt. tin dioxide. USE - Graphene nanomaterial composite is used for electrode of lithium battery. ADVANTAGE - The graphene nanomaterial composite has excellent electrochemical performance and coulombic efficiency even after repeated usage. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of graphene nanomaterial composite, which involves mixing the carboxymethyl chitosan and dextran in hydrochloric acid solution, adding a mixed crosslinking agent to crosslink and prepare microspheres, dispersing graphene oxide in water, adding aqueous ammonia and ethylenediamine, stirring the reacting to prepare modified graphene oxide, reacting the microspheres with potassium periodate, mixing the pretreated microspheres, reacting the pretreated microspheres with the modified graphene oxide dispersion to obtain modified microspheres, mixing and reacting the modified microspheres with an aqueous solution of tin source, carbonizing to obtain graphene nanomaterial composite, and performing index analysis of the graphene nanomaterial composite.