Benzophenone as indicator detecting lithium metal inside solid state electrolyte

Abstract Solid-state electrolytes are regarded as the “key” materials for enabling the usage of lithium metal in high energy density lithium battery systems. However, recent reports suggest lithium dendrites still exist in solid-state electrolytes after cycling. Moreover, due to the low concentration of lithium dendrite inside solid-state electrolyte and the unique characteristic of lithium, conventional methods such as EDS (Energy Dispersive X-Ray Spectroscopy) cannot detect lithium. Analyzing lithium dendrite in solid-state electrolyte usually requires complicated and expensive equipment such as neutron diffraction, which brings extra barrier to explore the mechanism of growth of lithium dendrite in the solid-state electrolyte and exploring the solution to this problem. In this work, we report a simple and effective method to visualize the existence of lithium metal inside solid-state electrolytes in very early stage. This method may benefit the exploration of the growth mechanism of lithium dendrite inside solid-state electrolytes and solving this problem eventually.