| 초록 |
Developing reliable energy storage system is pivotal to meet the world’s growing energy demands. Among the promising technologies for the large-scale ESS, the VRFB uses vanadium reactants on both the anode and cathode half-cells, and consequently, cross-contamination of ions causes no harm on battery capacity, prolongs their cycle life and operates at high energy efficiencies. However, the development of the VRFB has been inhibited by low energy density and narrow operation temperature window (10 to 30oC), which are mainly limited by the solubility of various vanadium cations in the electrolyte system. In particular, the V+5 species indicate poor stability at elevated temperatures. This thermal and chemical instability is observed as V2O5 particles precipitation, which results in energy loss and failure of the battery. In this work, we studied recycling of waste positive electrolyte in VRFB by a reducing agent. The positive electrolyte in VRFB is characterized using UV/Vis spectrophotometry, Raman spectrophotometry, and electron spin resonance (ESR). |
