Recent advances in electrospun carbon fiber electrode for vanadium redox flow battery: Properties, structures, and perspectives

Abstract With the development and utilization of new energy, people’s demand for large-scale energy storage system has become increasingly urgent. Vanadium redox flow battery (VRFB), as one of the most promising energy storage technologies, has attracted increasing attention due to its long cycle life, high efficiency and environment-friendly. Cheap and efficient electrode materials have been a research hotspot of VRFB. In recent years, electrospun carbon fiber shows excellent catalytic performance as electrode of VRFB, ascribing to its good conductivity and marvelous specific surface area. However, the improvement of VRFB performance by unmodified electrospun carbon fiber is still limited. Therefore, it is necessary to further modify the electrode to improve its electrochemical performance. In this paper, the research progress of various modification methods of VRFB electrospun carbon fiber electrodes in recent years was reviewed from two aspects. One is to adjust the surface activity, which involves introducing metal, metallic oxide, carbon nanomaterial, and heteroatom into electrospun carbon fiber. The other one is to improve the structure of electrospun carbon fiber, including the increasement of graphitization and other structure optimizations. Furthermore, the research direction of further improving the catalytic performance of electrospun carbon fiber electrode was proposed.