Electrochemical and Chemical Stability of Solid Electrolyte–Electrode Interfaces: A First Principles Computation Study

Tuesday, 3 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
Y. Zhu, X. He, and Y. Mo (University of Maryland, College Park)
All-solid-state Li-ion battery based on solid electrolyte materials is a promising next-generation energy storage technology. It can provide intrinsic safety, enable high-voltage electrode materials, and boost the achievable energy density. Currently, the key performance limiting factor of all-solid-state Li-ion battery is the high interfacial resistance and interfacial degradation at the solid electrolyte-electrode interfaces.

In this presentation, I will show how we use first principles computation to provide unique insights and fundamental mechanisms at these buried interfaces, which are difficult to access in experiments. We systematically investigated and compared the electrochemical stability and chemical stability of the solid electrolyte-electrode interfaces, and studied how these interfaces affect the battery performance, including interfacial resistance, long-term stability and cyclability.

Our computation results suggest the critical role of decomposition interphase layers at electrolyte-electrode interface and the significant effects of these interphase layers on the electrochemical performance of the all-solid-state Li-ion batteries. Different types of interfaces between solid electrolyte and electrode materials may have different problems at the interfaces, which require different interfacial engineering strategies to resolve. The mechanisms of artificial layers to improve the interfacial properties are also revealed by our computation. This computational study provides novel insights and general guidance for interfacial engineering in all-solid-state Li-ion batteries.