Highly conjugated (conjugation length may be more than 50 double bonds) polypyrrole films have been synthesized electrochemically at low current density. The polymers display a detailed fingerprint region between 2.5 and 3.0 V versus Li in cyclic voltammograms with well-defined, reproducible peaks. This region contains information about the identity of solvent and anion present. Ah 16 combinations of propylene carbonate, acetonitrile as solvent, and ClO4-, CF3SO3- as anion during polymerization and cycling, respectively, have been investigated. The solvent seems to be exchanged during cycling. The cyclic voltammograms depend on complex interactions in the solvent/ion/polymer system.