▎ 摘　　要

NOVELTY - Nano-diamond powder and graphene composite electrode material comprises multi-layered sheet structure whose surface has corrugated pleats, and nano-diamond particles adsorbed on the surface of graphene sheets, where the mass ratio of nano-diamond powder and graphene, is 0.066-0.334:1. USE - The composite electrode material is useful in the production of cathode of lithium-ion battery (claimed). ADVANTAGE - The composite electrode material provides good high specific capacity, good cyclic performance and large discharging coulomb efficiency of cathode. The method is simple, economical and environmental-friendly. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing composite electrode material, comprising dissolving citric acid and urea in de-ionized water, to obtain colorless transparent solution, then subjecting nano-diamond powder to high-frequency ultrasonic treatment for 30-60 minutes, and placing the obtained solution in a microwave oven at power of 850 W, heating for 10-15 minutes, to obtain solution changed from colorless to brown and changed into the dark brown solid compound, carbonizing the solid compound below 900 degrees C under the protection of inert gas for 2 hours and drying; and (2) use method of composite electrode material in production of cathode of lithium-ion battery, comprising mixing nano-diamond powder and graphene composite electrode material, crushing, grinding until the powder particle size reaches nano-level, mixing with carbon black, grinding in presence of polyvinylidene fluoride, adding 1-methyl-2-pyrrolidone into a magnetic stirrer, to obtain viscous fluid, coating the viscous fluid on current collector, drying at 120 degrees C, cutting the material into electrode shape, to obtain lithium-ion battery cathode.