A polythiophene derivative bearing two electroactive groups per monomer as a cathode material for rechargeable batteries

A polythiophene derivative bearing two (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl (TEMPO) radicals per monomer unit has been synthesized and demonstrated to have a completely reversible electrochemical oxidation. This polymer has been incorporated as cathode-active material into a rechargeable Li battery. In this article, we demonstrated construction and charge/discharge characteristics of this organic radical battery. The battery has showed an initial specific discharge capacity of 88.8 Ah/kg (about 82 % of the theoretical capacity which is 108.8 Ah/kg) and an average output voltage of 3.6 V. The specific energy density discharged initially by the battery has been measured to be 321 mWh/g.