A Review of Research Progress on Anode Material for Vanadium Redox Flow Batteries

Imperial College London, London SW7 2AZ, United Kingdom

^* Corresponding author: Ziheng.zhao22@imperial.ac.uk

Abstract

Over the past few decades, the heavy reliance on fossil fuels has led to severe environmental degradation and resource depletion. To address these challenges, renewable energy sources such as solar and wind power have been expanding scales. However, the variability and intermittency of these renewable energy sources pose challenges to the stability of power grids, highlighting the crucial role of energy storage technologies. Among various energy storage options, vanadium redox flow batteries (VRFBs) have turned up to be a promising solution for their high energy efficiency, long cycle life, and flexible scalability. Nevertheless, the sluggish reaction kinetics at the anode, along with the suboptimal hydrophilicity and limited active sites on conventional graphite electrodes, have been identified as major bottlenecks restricting the performance of VRFBs. This review comprehensively compares and discusses four primary strategies for enhancing anode materials in VRFBs, namely thermal treatment, chemical etching, doping, and colony growth. Additionally, the challenges associated with VRFB anode materials are analyzed, and future research directions are proposed.