Lithium‐Free Redox Flow Batteries: Challenges and Future Prospective for Safe and Efficient Energy Storage

Abstract Considering the costs, waste, and impact on the environment of current energy consumption, accurate, cost‐effective, and safely deployed energy storage systems are required. Lithium (Li)‐free redox flow batteries (RFBs) are a feasible solution. RFBs can store enormous amounts of energy effectively and are increasingly used for large‐scale applications. The use of RFBs has significantly enhanced the performance of energy storage systems and effectively reduced the costs and wastage of energy storage operations. Vanadium‐based RFBs are an emerging energy‐storage technology being explored for large‐scale deployment owing to their numerous benefits, including zero cross‐contamination, scalability, flexibility, extended life cycle, and nontoxic working state. This study describes the fundamental operating principles of redox flow battery‐based systems as well as the design considerations and constraints placed on each component. It discusses recent progress in the design and deployment of RFBs for energy‐related applications and the remaining obstacles and prospects. Finally, this study highlights the enormous potential of RFBs and suggests some solutions to scale up the use of RFBs in the near future.