Vanadium flow battery: Bi promotes all-climate energy storage
Vanadium flow battery (VFB) is a fast going and promising system for large-scale stationary energy storage. However, drawbacks such as low power density and narrow temperature window caused by poor catalytic activity of graphite felt (GF) electrodes limit its worldwide application. In this paper, Bi, as a low-cost, no-toxic and high-activity electrocatalyst, is used to modify the thermal activated GF (TGF) via a facile hydrothermal method. Bi can effectively inhibit the side reaction of hydrogen evolution in wide temperature range, while promoting the V2+/V3+ redox reaction. As a result, the VFB assembled with Bi/TGF as negative electrode demonstrates outstanding rate performance and excellent durability in all-climate conditions.