▎ 摘　　要

NOVELTY - Carbon nanotube graphene/silicon-carbon composite material comprises silicon-carbon secondary particles formed by reacting and compounding silicon-carbon primary particles with a first silane coupling agent and carbon nanotubes, and a graphene layer coated on the surface of the silicon-carbon secondary particles, where the graphene layer reacts with a second silane coupling agent and the silicon-carbon secondary particles to coat the surface of the silicon-carbon secondary particles. USE - The composite material is used as a cathode material of a lithium ion battery (claimed). ADVANTAGE - The composite material forms a three-dimensional structure, improves the conductivity of the silicon material, effectively suppresses the volume change of the silicon material and improves the cycle stability of the material. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the composite material, involving (a) dispersing the first silane coupling agent in water, hydrolyzing, adding first surfactant, carbon nanotubes and silicon carbon materials, reacting the obtained mixed solution under stirring conditions and filtering to obtain silicon-carbon secondary particles, (b) dispersing the second silane coupling agent in water, hydrolyzing, adding the second surfactant, silicon-carbon secondary particles and graphene oxide, ultrasonically processing until the dispersion is uniform, and spray drying, and (c) calcining the spray-dried product to obtain the product.