PI: Fikile Brushett, Department of Chemical Engineering; Adam Willard, Department of Chemistry, MIT
PI: Keith Stevenson, Center for Electrochemical Energy Storage and Center for Energy Systems, Skoltech
Low cost high performance energy storage technology is needed to improve grid resiliency and to facilitate the widespread deployment of renewable resources. Redox flow batteries (RFBs) are particularly appealing for many of these grid storage applications due to their independent scaling of power and energy, long operational lifetimes, and simplified manufacturing. State‐of‐the‐art aqueous RFB technologies are too expensive for ubiquitous adoption. Transitioning to nonaqueous electrolytes and incorporating a deposition / dissolution electrode (e.g., lithium (Li) metal) offers a pathway to system energy densities greater than both conventional RFBs and current generation Li‐ion batteries, which, in turn, reduces costs of energy storage. Despite this promise, nonaqueous hybrid Li‐RFBs are hampered by high resistance and limited lifetime due, in large part, to lack of suitable membranes. In this work, we will develop new composite polymer‐inorganic membranes with improved mechanical characteristics, enhanced temperature and chemical stability, and optimized transport features (Li+ conductivity >10‐4 S cm‐1, lowered interfacial resistance). When combined with other emerging materials developed by the team (new posolytes, new negative electrode), these membranes will allow us to develop a nonaqueous hybrid Li‐RFB (3‐4 V) with high energy (>60 Wh kg‐1) and power density (>50 W kg‐1). Generalized guidelines will be formulated for the deterministic design of stable and soluble organic posolytes, conductive and selective composite membranes, and electrochemical interfaces with facile ion transfer. Successful implementation of this project will establish the foundational scientific knowledge needed to develop and commercialize a disruptive next generation RFB technology for large scale energy storage.