Advanced aqueous redox flow batteries design: Ready for long-duration energy storage applications?

Critical developments of advanced aqueous redox flow battery technologies are reviewed. Long duration energy storage oriented cell configuration and materials design strategies for the developments of aqueous redox flow batteries are discussed Long-duration energy storage (LDES) is playing an increasingly significant role in the integration of intermittent and unstable renewable energy resources into future decarbonized grids. Aqueous redox flow batteries (ARFBs) with intrinsic high scalability, safety and power capability can be promising candidates for LDES if a substantially decreased levelized cost of storage is achieved. In this Perspective, we present a top-down analysis of existing ARFBs for long-duration applications, including ARFB cell configurations and materials design strategies for both membranes and redox active materials. In addition, we discuss the types of testing and demonstration needed at the lab-scale for feasible projection for future large-scale systems. The LDES-oriented materials design strategies serve as a guidance for the research and developments for future advanced ARFBs in large-scale deployments. Graphical abstract