Speaker: Prof. Matthew T. McDowell, Georgia Institute of Technology
Program Description:
Solid-state batteries offer improved energy density and safety characteristics compared to Li-ion batteries, but improved understanding if dynamic processes at solid/solid electrochemical interfaces is necessary to enable engineering of better systems. Here, I present my group’s recent work using operando X-ray tomography to reveal interfacial dynamics in solid-state batteries. The evolution of the interface between lithium metal electrodes and a sulfide solid electrolyte was investigated with X-ray synchrotron computed microtomography, and the formation of interfacial voids was observed and quantitively linked to electrochemical behavior. Void formation and current constriction due to lithium stripping was found to be the primary cause for cell failure. I will also discuss our work on using in situ X-ray imaging to investigate mechanical fracture and chemo-mechanical degradation at interfaces within solid-state batteries. These results are important for guiding the creation of controlled interfaces for enhanced cycle life.
