High Energy Efficiency With Low-Pressure Drop Configuration for an All-Vanadium Redox Flow Battery

In this paper, we present experimental studies of electrochemical performance of an all-vanadium redox flow battery cell employing an active area of 103 cm(2), activated carbon felt, and a novel flow field, which ensures good electrolyte circulation at low pressure drops. Extended testing over 151 consecutive charge/discharge cycles has shown steady performance with an energy efficiency of 84% and capacity fade of only 0.26% per cycle. Peak power density of 193 mW cm(-2) has been obtained at an electrolyte circulation rate of 114 ml min(-1), which corresponds to stoichiometric factor of 4.6. The present configuration of the cell shows 20% improved in peak power and 30% reduction in pressure drop when compared to a similar cell with a different electrode and a serpentine flow field.