A composition for forming an electrode for a lithium ion secondary battery includes a carbonaceous material combined with a fullerene material including fullerene species having a carbon content of C.sub.n, where n.gtoreq.100. The composition is heated to a temperature of 100.degree. C. or greater to facilitate reaction and/or diffusion of the fullerene material with the carbonaceous material, and also to remove lower molecular weight (C.sub.<100) fullerenes from the composition. In addition, other extraction techniques may be utilized in combination with heat treatment to selectively remove fullerene species from the fullerene material. The composition enhances the electrochemical performance of the electrode in the lithium ion battery.