Regenerative Fuel Cells

Electrochemical flow reactors are device architectures that present benefits for medium to large electrical energy storage (i.e., from 2 to 10 h) due to their ability to store the energy in active species dispersed in a fluid (gas or liquid). Those species can be placed in reservoirs isolated from the electrodes, and this enables the independent scaling of power and capacity, which is not possible for traditional batteries such as lithium-ion or lead-acid. Depending on the nature of those fluids and each half-cell reaction, the electrochemical flow reactors can be called redox-flow batteries (RFBs, liquid-liquid), hybrid redox-flow batteries (HRFBs, solid-liquid), or regenerative fuel cells (RFCs, gas-liquid).