Microstructure and Pressure-Driven Electrodeposition Stability in Solid-State Batteries

Interfacial deposition stability at the Li-metal-solid electrolyte interface in all solid-state batteries is governed by stress-transport-electrochemistry coupling conjunction with polycrystalline/amorphous solid architecture. In this work, we delineate optimal microstructure comprising grains, grain boundaries, and voids possessing desirable ionic conductivity elastic modulus for superior transport strength. An analytical formalism provided to discern impact of external “stack” pressure-induced mechanical stress on electrodeposition stability; magnitudes obtained are megapascal range, considerably diminishing stress-kinetics effects. For experimental stack pressures ranging up 10 MPa, reaction kinetics negligibly small, overpotentials dictate stability. High current density operation stable can be ensured ample pressure, high temperature, low surface roughness a shear ratio Li-metal.