Characteristics of Carbon Paper as Electrode for Vanadium Redox Flow Battery

The carbon paper (CP) heat-treated at 435 degrees C for 10h were characterized by FTIR spectroscopy and BET, and their electrochemical behaviors were investigated by cyclic voltammograms, impedance spectroscopy and charge-discharge techniques. The results show that -COOH functional groups form after heat-treated for 10h and specific surface area increases significantly. The vanadium redox battery with modified CP electrode exhibits excellent performance at current density of 50mA/cm(2). The average current efficiency reaches 95% and average voltage efficiency reaches 89%. The improvement of electrochemical performance for the electrode is ascribed to the -COOH group and the special surface of CP.