Unlocking the Energy Capabilities of Lithium Metal Electrode with Solid-State Electrolytes

Although solid-state lithium (Li) batteries theoretically have higher energy density and better safety than organic solvent-based Li-ion batteries, they currently suffer from problems such as poor power density and rapid performance degradation, hindering their wide applications. The cause of these problems can be largely related to the electrode material|solid-state electrolyte (SSE) interface, which sets a significant barrier for Li+ ions to transport across. As a result, an in-depth fundamental understanding of the reaction and process occurring at the electrode material|SSE interface is of paramount importance to alleviate the interfacial impedance and enhance the performance of solid-state Li batteries. This Perspective focuses on the Li|SSE interface, points out the critical challenges for a reversible, dendrite-free, and high-rate Li electrode, recapitulates potential resolutions for these challenges, and highlights the significance of advanced research techniques having the ability to interrogate the buried Li|SSE interfaces.