Ag nanoparticles were added to 2,5-dimercapto-1,3,4-thiadiazole (DMcT)-polyaniline (PAn) composites to improve charge-discharge performance of the composites as a cathode material for lithium rechargeable batteries. The effect of the Ag nanoparticles addition to the DMcT-PAn composite film was investigated. Adding the nanoparticles, the DMcT-PAn composite film containing Ag nanoparticles showed enhanced current density compared to a DMcT-PAn composite film without Ag nanoparticles. Ag nanoparticles acts as conductive and catalytic material. UV/vis spectroscopic analysis suggested strong interactions between DMcT and Ag nanoparticles, while only weak interactions were suggested between PAn and Ag nanoparticles. The DMcT-Ag nanoparticles complex formation was confirmed by observing an X-ray photoelectron spectroscopy signal indicative of an Ag-sulfur bond, which prevents the migration of the DMcT out of the cathode. (C) 2003 The Electrochemical Society.