Redox Flow Lithium-Ion Batteries for Large-Scale Energy Storage
In our previous study, we have demonstrated RFLB half-cells. Here we report our latest progress in the development of RFLB full systems. This comprises the development of robust redox mediators for both anode and cathode, Li+-conducting membranes, as well as mechanistic studies on the Li+-coupled heterogeneous charge transfer — the essential process for the operation of RFLB. With the above efforts, we have successfully fabricated the first RFLB full cell with LiFePO4 and TiO2 as the cathodic and anodic Li-storage materials, respectively. The system functions with power generated in the cell via the redox reactions of shuttle molecules dissolved in the catholyte and anolyte, while energy stored in the two Li-storage materials, which are kept in two separate energy tanks. RFLB combines the great system flexibility (decoupled power and energy units) of redox flow battery with the high energy density (the same Li-storage materials while no conducting additives and binder required) of lithium-ion batteries, revealing significant potential to its application for large-scale stationary and automotive energy storage.4
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