Developing a Solid-State Electrolyte for Lithium-Air Batteries
Lithium-air (Li-oxygen) batteries are an emerging type of lithium-based batteries that can serve as an alternative to conventional lithium-ion batteries currently used in cell phones, electric vehicles, etc. Lithium-air batteries have a higher gravimetric and volumetric energy density than lithium-ion batteries; making them exciting and thereby opening new opportunities for their use and improving the performance of current devices. Imagine your iPhone and tablet device weighing less because of Li-air batteries, and also having a much longer battery life. Or imagine driving from Boston to New York with just one charge of your Li-air battery and without the need for gas. That is just a glimpse of the immense potential.
There are numerous challenges facing lithium-air batteries before they can realize their full commercial potential. One of these challenges involves developing an electrolyte capable of dissolving oxygen from the air, and also allowing for the quick diffusion of oxygen ions. Some of the desired electrolyte properties are as follows: allow for the quick diffusion of Li ions, no reaction with lithium metal anode, allow for the formation of lithium peroxide (upon discharge) and the oxidation of lithium peroxide upon charge. In addition, it is also desired to eliminate the volatility and flammability problems that plague conventional organic liquid based electrolytes. Hence, my research in the Hammond Lab will be focused on developing a solid-state polymer electrolyte that has the desired electrolyte properties, that can eliminate the volatility and flammability challenges of liquid electrolytes, and also add mechanical stability among many other desired properties. Improvements in solid-state electrolyte design will not only be useful for Li-air systems, but other battery designs. With these developments, we can bring Li-air and other battery systems ever more closer to fulfilling their commercial promise.
Bruce et al. "Li-O2 and Li-S batteries with high energy storage." Nature Materials 2012, 11, 19-29.