Membrane-Free Redox Flow Batteries
The MFreeB (Membrane-Free Redox Flow Batteries) project proposes a disruptive, versatile and scalable redox flow battery in which the vanadium-based redox couples currently used are replaced by low-cost, abundant and environmentally friendly organic molecules. In addition, the problematic ion-exchange membrane that serves as a separator between electrolytes is completely eliminated through the development of immiscible redox electrolytes. New thermodynamic, fluid dynamic and engineering aspects, never before considered in energy storage, will become key elements in the development of this technology, representing a paradigm shift in energy storage.
One of the main barriers to the global deployment of energy storage systems coupled with renewable energy generation plants and distribution grids is their high investment cost. The proposed membrane-free redox flow batteries (RFBs), which use organic redox couples, could achieve investment costs well below the U.S. Department of Energy (DoE) target threshold of $150/kWh, as they eliminate membrane costs, use low-cost organic compounds and do not require expensive corrosion-resistant materials. Furthermore, these batteries will not require membrane cleaning and replacement, nor electrolyte rebalancing after prolonged use, making operation and maintenance significantly simpler and more suitable for domestic applications.
Based on these characteristics, the membrane-free batteries proposed in this European Research Council (ERC) project could drive the redox flow battery market for stationary energy storage applications.
