▎ 摘　　要

NOVELTY - Polyimide/graphene flexible composite material is claimed. The polyimide/graphene flexible composite material has a three-dimensional interpenetrating porous structure, and the polyimide is coated on the graphene. USE - The polyimide/graphene flexible composite material is useful as flexible self-supporting electrode material for lithium-ion batteries (claimed). ADVANTAGE - The polyimide/graphene flexible composite material has better flexibility and electrical conductivity has higher reversible capacity and excellent cyclical stability, simple preparation method, easy operation, and low cost; and is environmentally friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparation of polyimide/graphene flexible composite material comprising (i) adding pyromellitic dianhydride and p-phenylenediamine at the molar ratio of 1:1-1:3 into the solvent, dissolving, and carrying out polycondensation reaction under a nitrogen atmosphere to obtain polyamic acid solution, mixing the obtained polyamic acid solution with graphene oxide to obtain uniform viscous liquid, where mass ratio between pyromellitic dianhydride and graphene oxide is 15:1-35:1, (ii) adding the viscous liquid obtained in step (i) into the solvent for dilution, carrying out hydrothermal reaction and cooling to obtain polyimide-coated graphene oxide composite material, and (iii) dissolving graphene oxide in a solvent to obtain graphene oxide solution, mixing the polyimide-coated graphene oxide composite material obtained in step (ii) with the graphene oxide solution at a ratio of 1g:10ml-3g:10ml, suction filtrating, and carrying out heat treatment under nitrogen atmosphere to obtain final product.