Nanoporous Ceramic Ion Exchange Membranes in Non-Aqueous Redox Flow Batteries

Replacement of on-demand fossil fuels with intermittent renewable energy technologies such as solar cells and wind turbines is not possible without grid-scale energy storage. Redox flow batteries are a safe, scalable and long-lasting solution to this problem but two components, the membrane & electrolyte, accounts for more than 60% of the battery cost which limits market penetration. New low-cost non-aqueous electrolytes have been developed but they lack a suitable membrane technology. Therefore, there is a strong need for a new high-performance and inexpensive membrane that can enable the use of lower cost energy storage materials. This Phase I project will address this problem by developing a novel flow battery membrane using one of the most abundant materials on earth: silica. Sol-gel processing is a scale-able, low- cost method that enables silica to be engineered to have pores only a few molecules wide. Membranes can then be functionalized to provide high ion transport and selectivity which is necessary for charging and discharging the battery. Membranes will be further tuned to optimize performance in low-cost non-aqueous redox flow batteries. Beyond enabling a lower-cost battery chemistry, this novel flow battery membrane will cost 10× less to produce than current membranes. Delivering significant battery cost savings will increase commercial adoption and provide even more engineering, manufacturing and sales jobs at U.S.-based flow battery manufacturing companies. Increased adoption of grid-scale energy storage will lead to fewer adoption barriers for other renewable energy technologies (e.g., wind and solar) which will continue to offset large quantities of CO2 and provide U.S. energy security. This tax-payer funded investment will have a multi-faceted impact in the form of job creation, new manufacturing efforts, energy cost savings, environmental benefits and federal tax revenue.