Brett Helms1 Chengyin Fu1 Andrew Ells1 Zeeshan Ahmad2 Victor Venturi2 Venkat Viswanathan2

1, Lawrence Berkeley National Lab, Berkeley, California, United States
2, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States

The realization of a low-cost, safe, reversible, high-areal capacity lithium metal electrode for solid-state batteries has remained elusive despite ongoing advances in anode protection using ion-conducting ceramics and glasses as well as organic and inorganic passivating layers. Here, I will outline a framework to understand the successes and failures of these differentiated materials platforms on the basis of their mechanical properties, transport properties, and partial molar volume considerations for solid-ion conductors relative to the lithium anode. Within this framework, I will also highlight an unexpected opportunity for suppressing lithium metal dendrites using soft solid-ion conductors. I will then detail the extent to which these predictions deliver on their promise, from early-stage discovery science and in-depth synchrotron hard x-ray techniques to platform maturation from coin cells to pouch cells.