Cost-effective iron-based aqueous redox flow batteries for large-scale energy storage application: A review

In order to solve the current energy crisis, it is necessary to develop an economical and environmentally friendly alternative energy storage system in order to provide potential solutions for intermittent renewable energy sources such as solar and wind energy. Redox flow battery (RFB) is reviving due to its ability to store large amounts of electrical energy in a relatively efficient and inexpensive manner. RFBs also have unique characteristics, which make them more attractive than conventional batteries. For example, they can separate the rated maximum power from the rated energy, and have greater design flexibility. The iron-based aqueous RFB (IBA-RFB) is gradually becoming a favored energy storage system for large-scale application because of the low cost and eco-friendliness of iron-based materials. This review introduces the recent research and development of IBA-RFB systems, highlighting some of the remarkable findings that have led to improving battery performance over the years. The role of components such as the electrode, membrane, and electrolyte in the overall function and the relevant work in this field are comprehensively reviewed and discussed. Finally, the challenges and future research directions are proposed briefly.