Dr. Lingzi Sang

Abstract

All-solid-state sodium batteries use earth-abundant elements, non-volatile and non-flammable electrolytes, and are considered a safe and sustainable choice to satisfy the growing demand for energy storage. Using solid-state electrolytes (SEs) also eliminates the need for packing when fabricating tandem cells, potentially enabling further enhanced energy density. Developing sodium-ion conductors that exhibit high electrochemical stability is an essential step toward long-lasting and high-performance solid-state batteries. As potential electrolyte materials for all-solid-state sodium batteries, sodium thioantimonate and its substituted analogs exhibit high Na+ conductivity. To date, a couple of key challenges still exist for developing (electro-) chemically stable thioantimonate-based SEs. These challenges include batch-to-batch variations for producing substituted SEs, and unwanted electrochemical decompositions occurring at the SE/electrode interface.

This seminar will discuss in-depth, multidisciplinary characterizations that can correlate the structure of thioantimonate SEs with their evolving electrochemical performances during the battery cycling process. In particular, X-ray absorption, Raman, NMR, X-ray diffraction, and electron imaging characterizations are combined to provide structural- and morphological-level understanding within the SE materials and the SE/electrode interfaces. These characterizations provide insights into the optimal synthetic approach of these SE materials. The interpretation of the SE/electrode interfacial chemistry made possible by the in-situ analysis marks the criterion of an ideal functional protective layer towards high-performance, long-lasting all-solid sodium batteries.

Speaker Bio