▎ 摘　　要

NOVELTY - Lithium salt-coated graphene-doped silicon-carbon composite material, is claimed. The silicon carbon cathode material has core-shell structure, the inner core is graphene-doped nano-silicon, the outer shell is lithium salt, and the mass ratio of the outer layer is 1-10 wt.%. USE - Used as lithium salt-coated graphene-doped silicon-carbon composite material. ADVANTAGE - The composite material: utilizes the action of catalyst to grow graphene vertically on the surface of nano-silicon to reduce impedance and expansion; at the same time, reacts with the amination solution to form structurally stable inner core; uses the synergistic effect of the electronic conductivity of graphene and the high ionic conductivity of the inorganic lithium salt in its shell; relays on its core porous structure by reducing its impedance; can quickly intercalate and desorb lithium ions through inorganic lithium salts; improves fast charging performance; and reduces swelling. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the composite material, comprising (1) grinding the magnesium metal and silicon dioxide in high-speed grinder 1-48 hours, transferring to tube furnace, heating to 400-600degrees Celsius under argon atmosphere for thermal reduction 1-48 hours, adding to the nitric acid solution, carrying out soaking pickling, removing metal magnesium, and drying to obtain carboxylated porous nano-silicon A, where the molar ratio of magnesium and silicon dioxide is 2-4:1, (2) preparing catalyst organic solution with mass concentration of 1-5 wt.%, adding porous silicon A, filtering after uniform dispersion, drying, transferring to tube furnace, raising the temperature to 600-1000degrees Celsius under the carbon source gas by vapor deposition method, and keeping for 1-6 hours to grow graphene on the surface to obtain the graphene-doped silicon-carbon composite material, where the mass ratio of catalyst and porous material A is 0.5-2:100, and (3) embedding the lithium salt into the surface layer of the graphene-doped silicon-carbon composite through high-speed particle beam bombardment, carrying out the parameters of the particle implantation method in oxygen atmosphere, where the gas flow rate is 1-10 sccm, the injection temperature is 100-500degrees Celsius and the time is 10-120 minutes under the air pressure 1-10x10-4 Pa, and obtaining lithium salt-coated graphene-doped silicon-carbon composite material.