FERRIC ION REDUCTION SYSTEM TO ENABLE ELECTROLYTE REBALANCE WITHIN AN IRON FLOW BATTERY

A flow battery system with a cathode cell including a first electrode, an anode cell includes a second electrode, and a membrane between the two cells. A first electrolyte tank includes a catholyte. A second electrolyte tank includes an anolyte. The system includes two rebalancing cells. A first rebalancing cell is in fluid communication between the cathode cell and the first electrolyte tank and is configured to reduce active species from the catholyte. The second rebalancing cell is in fluid communication with the first electrolyte tank and the second electrolyte tank such that the first electrolyte tank and the second electrolyte tank are in direct fluid communication. The second rebalancing cell is configured to reduce active species from the catholyte and the reduced catholyte may be combined directly with the anolyte. The second rebalancing cell may be a chemical reactor, a catalytic reactor, or an electrochemical reactor.