In this study, the charge–discharge characteristics of polyaniline films used as cathodes in a lithium battery were determined. The polymer films were synthesized in a propylene carbonate medium in the presence of trichloroacetic acid. The discharge capacity and the coulombic efficiency observed for polyaniline thin films were 107Ahkg−1 and 97.5%, respectively. For thick polyaniline films the values obtained were 82Ahkg−1 and 95.0%, for the discharge capacity and coulombic efficiency, respectively. These values were stable after the seventh charge–discharge cycle.