New Sodium-Based Anode Materials for Solid and Liquid-Electrolyte Batteries

Due to its chemical, electrochemical, and mechanical properties, sodium offers promise in batteries both as a metallic electrode material and as a charge-carrying ion. Here I will discuss my group’s recent efforts in the development and characterization of sodium-based anodes in battery systems. Sodium metal has a lower yield strength than lithium metal, and we show that sodium offers benefits when incorporated into solid-state lithium batteries with sulfide solid-state electrolytes. In particular, creating alkali metal mixtures is shown to enable the spontaneous development of self-regulating interfaces during discharge of solid-state batteries, which enhances contact retention and improves battery lifetime. Cryo-FIB-SEM and operando X-ray computed tomography are used to visualize the evolution of these electrodes. In addition to solid-state batteries, the development of carbon materials with controlled structure and pore size for sodium-ion batteries will be discussed, with the potential to enable a domestic supply chain for sodium battery manufacturing. Overall, our findings show the importance of understanding material evolution to improve performance in batteries.