A general, highly efficient, high temperature thermal pulse toward high performance solid state electrolyte

Surface contamination and degradation are two main issues leading to performance decay of ceramic-based solid-state electrolytes (SSEs). The typical strategies used to clean surface contaminants and restore ceramic materials involve mechanical polishing or high temperature thermal treatment. However, mechanical polishing can cause other side reactions and cannot clean contaminants on the grain boundaries of SSEs, while conventional thermal treatment using a furnace is often energy- and time-intensive, as the heating and cooling processes are slow. In this work, we for the first time demonstrate a high temperature thermal pulse technique for rapid ceramic surface processing. As a demonstration, we cleaned a garnet-based Li conductive SSE featuring lithium carbonate surface contamination in less than 2 s. The thermal pulsed garnet SSE exhibits an improved ionic conductivity of 3.2 × 10−4 S/cm—a two-fold increase compared to the starting material. Symmetric cells featuring the thermal pulsed garnet SSE can cycle at current densities up to 500 µA/cm2, while control cells short-circuit at a current density of 100 µA/cm2.