Chelation Engineering Revitalizes Iron-Based Redox Flow Batteries.

Aqueous iron-based redox flow batteries (IRFBs) are promising candidates for cost-effective, large-scale energy storage. However, their development is hindered by persistent challenges, including hydrogen evolution reaction (HER), dendrite formation, sluggish kinetics, and active species crossover. Chelation engineering offers a transformative approach for overcoming these obstacles. By modifying the coordination environment of metal ions, chelation directly influences the electrochemical properties of metal ions and the thermodynamics of redox reactions, leading to significant improvements in battery efficiency, cycle stability, and system scalability compared to conventional IRFBs. This work highlights the potential of chelation engineering in optimizing IRFB performance and outlines key research priorities to advance the development of chelated IRFBs for grid-scale energy storage applications.