Characterization of Carbon Fiber Electrode for Vanadium-Based Redox Flow Batteries

Electrochemical properties for two kinds of carbon felt electrodes were evaluated using single filament electrodes. Results of cyclic voltammogram (CV) measurements for both carbon fiber electrodes showed wide potential windows (-1.0 ~ +1.9 V vs. Ag/AgCl). In the case of felt sample 1 (thin electrode), which was actually used in the vanadium-based RFB, dispersion of oxidation and reduction peaks was smaller than that of sample 2 (thick electrode, general carbon felt electrode). Redox responses were also measured in the vanadium electrolyte. Sample 1 electrode showed low dispersion in redox responses and had suitable electrochemical property for vanadium-based RFBs.