▎ 摘　　要

NOVELTY - The method comprises adding graphene oxide material completely oxidized into a diluted acid solution, and stirring uniformly to obtain a component, adding carbon nano-tube powder into component, stirring uniformly, filtering, and taking filter residue to obtain graphene oxide/carbon nano-tube filter material, adding filter material of graphene oxide and carbon nano-tube filter material into dilute acid solution and stirring evenly, completing first acid washing operation, repeating acid washing operations for at least three times, extruding, granulating, drying and thermal reduction to obtain final product. USE - The method is useful for preparing graphene-carbon nano-tube composite material, which is useful as conductive additive in lithium ion battery. ADVANTAGE - The material: is environmentally friendly; has good conductivity; reduces acid purification process and waste liquid amount, acid cleaning cost, good dispersion uniformity and conductive balance problem. The method: improves conductivity of electrode material, and mechanical performance of composite material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) graphene-carbon nano-tube composite material; (2) graphene-carbon nano-tube composite slurry; and (3) preparing graphene-carbon nano-tube composite slurry.