The surface of natural graphite particles for the anode of dry-type polymer lithium ion batteries was modified by means of carbon coating and polyethyleneoxide (PEO) grafting. Carbon coating on graphite particles was achieved by a simple mixing of graphite particles with polyvinylchloride powders and heating up to 500 degreesC under a nitrogen gas flow. The graphite particles obtained were coated with carbon homogeneously. The carbon layer was oxidized by heating at 400 degreesC in static air to form carboxyl group and then PEO was grafted by esterification of the carboxyl group with terminal hydroxyl group of PEG. The dispersibility of the PEG-grafted particles in water was improved compared to that of untreated graphite particles. (C) 2000 Elsevier Science B.V. All rights reserved.