Abstract: | Herein, molecular layer deposition is used to form a nanoscale “zircone” protective layer on Li metal to achieve stable and long life Li metal anodes. The zircone‐coated Li metal shows enhanced air stability, electrochemical performance and high rate capability in symmetrical cell testing. Moreover, as a proof of concept, the protected Li anode is used in a next‐generation Li‐O2 battery system and is shown to extend the lifetime by over 10‐fold compared to the batteries with untreated Li metal. Furthermore, in‐situ synchrotron X‐ray absorption spectroscopy is used for the first time to study an artificial SEI on Li metal, revealing the electrochemical stability and lithiation of the zircone film. This work exemplifies significant progress towards the development and understanding of MLD thin films for high performance next‐generation batteries. |