New Zinc-Vanadium (Zn-V) Hybrid Redox Flow Battery: High-Voltage and Energy-Efficient Advanced Energy Storage System

摘要

Herein for the first time, we have reported the performance and characteristics of new high-voltage zinc-vanadium (Zn-V) metal hybrid redox flow battery using a zinc bromide (ZnBr2)-based electrolyte. The Zn-V system showed an open-circuit voltage of 1.85 V, which is very close to that of zinc-bromine flow cell. The obtained results exhibited a voltaic, Coulombic, and energy efficiencies of 88, 82, and 72% at 20 mA.cm(-2), respectively, in which low-cost microporous membrane was used as a separator. However, the cell tested using Nafion-117 membrane showed voltaic, Coulombic, and energy efficiencies of 84, 83, and 71%, respectively at a current density of 20 mA.cm(-2). Furthermore, the Zn-V cell performance is also compared with the Zn-Br-2 flow system to highlight the advancement of the new Zn-V system. The cell also showed stable performance up to 50 cycles at a current density of 20 mA.cm(-2).