Enhanced the performance of the vanadium redox flow batteries

초록

In this study, we investigated the addition of the tungsten catalyst into the electrolyte of the vanadium redox flow batteries (VRBs) and measured the performance of the cells with respect to the small concentration of the tungsten hexachloride as the precursor. The VRBs showed a clear improvement in electrochemical performance due to the deposition of tungsten catalysts (W metal, WO3) on the electrode. The presence of tungsten allowed the ionization of tungsten in the electrolyte during the battery cycling. The optimized concentration of the tungsten precursor was determined using electrochemical methods, which showed that the efficiency of the VRBs improved about 3 % after adding small amount of tungsten into the electrolyte. Particularly, the performance of cells in the negative electrolyte containing tungsten catalysts was significantly enhanced at the high current rates.