Highly Energy-Efficient Vanadium Redox Flow Batteries with Thermo-Chemically Activated Graphite Felt Electrodes

摘要

The Vanadium Redox Flow Battery (VRFB) is a promising energy storage technology for large scale stationary applications that require a long cycle life of over 10 years. The specific feature of VRFB is the slower kinetics of redox reactions (V~(2+)/V~(3+)) on the negative electrode (NE) as compared to the kinetics of the redox reaction (VO_2~+/VO~(2+)) on the positive electrode (PE) and poor kinetic reversibility. The commonly used electrodes for VRFBs are graphite felt electrodes (GFE). One of the main challenges facing these GFEs is their activation that enhances a rate of redox reactions due to the increase of GFE wettability and surface area. Another challenge is capability to maintain GFE activation over cycling.