Abstract: A method for making composites uses electrochemical polymer or copolymer coating of a carbon-based support by using a reaction system including (a) at least a monomer capable of forming a polymer on said support, (b) an aprotic solvent and (c) an electrolyte providing the resulting organic medium with an electrical conductivity for conducting therein electrolysis. The carbon support permanently forms the cathode, by applying either a potential or an electric current bringing the reaction system into the passivation zone corresponding to the first inhibition peak. The method forms a polymer grafted on the support.