Dendrite‐Free Formation of Anode‐Less Lithium Metal Through a Solid Glassy Electrolyte Film for Lithium Metal Batteries

Lithium dendrite formation remains a critical barrier to the reliable operation of lithium metal anodes, often causing internal short circuits and limiting cycle life. A promising strategy to mitigate this issue involves the use of glassy solid electrolytes (SEs), which promote stable lithium deposition and enhance interfacial integrity. In this study, the in situ formation of a lithium metal anode is demonstrated beneath a Li 2 OLi 2 SO 4 B 2 O 3 glassy SE layer on a copper substrate. The electrochemical properties of the plated lithium anode are systematically evaluated using impedance spectroscopy, cyclic voltammetry, and galvanostatic cycling in half‐cell configurations. This method significantly reduces internal resistance and improves long‐term cycling stability. Additionally, the direct formation of the lithium electrode through the SE offers a scalable and efficient approach to suppress dendrite growth. These results support the development of high‐performance, anode‐less solid‐state lithium batteries compatible with a wide range of active and structural materials.