FunLAB · Fundamental breakthroughs in Lithium-Air Batteries

Lithium-air batteries are a promising alternative to power the future electric vehicles. However, major improvements at the level of the fundamentals of the reactions will be required in order to improve their practical specific energy and rechargeability. Some of the challenges include: i) the instability of organic electrolytes in the presence of the superoxide radical formed as an intermediate in the reduction of oxygen, and ii) passivation of the electrode surface by the insoluble reaction products (lithium oxide and peroxide) leading to slow reaction kinetics. I plan to address these issues by means of a rational screening of soluble redox catalysts capable of decreasing the lifetime of the superoxide radical by rapidly transferring a second electron to the oxygen molecule. Such soluble redox catalysts will also act as shuttles, displacing the formation of insoluble reaction products from the electrode surface to the electrolyte, thus avoiding electrode passivation. The catalysts will be tested in selected electrolytes with good chemical stability. Redox active electrolytes will also be studied as they can potentially lead to very fast electron transfer reactions. Innovative approaches to avoid electrode passivation will be also investigated, including doping strategies to increase the conductivity of lithium oxides and peroxides and the application of ultrasound to erode the passivating layers on the electrode and enhance mass transport.