Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
Developing new battery technologies to satisfy the ever-growing demand of energy storage constitutes one of the great scientific challenges of society. Lithium-ion batteries are at the centre of this energy revolution as they power millions of portable electronics. Super-ionic conductivity of Li+ in solids, greater than 1 mS/cm, has stimulated renewed interest in solid-state Li-ion batteries, which would have substantial advantages in terms of safety and lifetime. While significant attention has been paid to the optimisation of the bulk ionic conductivity of Li, the electrochemical stability of solid electrolytes against the electrodes have been largely neglected. Although the garnet Li7La3Zr4O12 is a fast-ionic conductor and is believed to be stable against the Li-metal anode, recent reports show that Li dendrites propagate through the grain boundaries, compromising the safety and performance of the device. In this presentation, using first-principles modelling, we will present a detailed assessment of the competitive energetics of two distinct scenarios, i) the interaction of Li-metal and Li7La3Zr4O12 grains and ii) the interaction of Li7La3Zr4O12 grains.