Metalized Carbon Fiber Electrodes for High‐Performance Aqueous Redox Flow Batteries: The Dominance of Bismuth

ABSTRACT Electrochemical energy storage has become a key component for balancing energy supply and demand in the 21st century. Redox flow batteries (RFBs) are distinguished by their high safety, flexible control over power and energy, and long cycle life. While advancements in RFBs continue, including improvements from single cells to stacks through electrolyte chemistry, membrane engineering, and cell design, the fundamental development of electrodes still needs focused attention. This is because electrode materials are now viewed as active ensembles that influence the thermodynamics and kinetics of redox reactions, rather than just passive substrates. This review examines modifications of the most commercially available carbon/graphite felt electrodes through metal coatings, their synthesis methods, and benefits over uncoated felt. It discusses proposed catalytic mechanisms for metal‐decorated carbon electrodes and highlights challenges like metal dissolution and stability over time. Bismuth metal emerges as a promising candidate; however, further in‐depth studies are necessary both to clarifyits role in improving kinetics and to evaluate cost‐effectiveness through techno‐economic analysis.