Ag aerogel-guided interface reconfiguration enables ultra-durable sulfide all-solid-state lithium metal batteries

Sulfide-based all-solid-state batteries (ASSBs) are among the most promising candidates for next-generation energy storage systems due to their high ionic conductivity and intrinsic safety. However, the unstable interface between lithium (Li) metal and sulfide electrolytes induces severe side reactions and dendrite growth, which limits long-term performance. Herein, we propose a scalable room-temperature roll-pressing strategy, which uses an ultrathin silver (Ag) aerogel as a structural interlayer, to fabricate a LiAg composite anode. The Ag layer facilitates homogeneous lithium-ion (Li⁺) flux and suppresses interfacial degradation. Electrochemical testing reveals that the Li-Ag|Li₆PS₅Cl|Li-Ag symmetric cell achieves a doubled critical current density (2.7 vs. 1.3 mA cm^-2) and prolonged cycling stability (>4000 h at 1.2 mA cm^-2) compared to the Li|Li₆PS₅Cl|Li symmetric cell. Furthermore, full cells employing LiAg composite anodes demonstrate enhanced capacity retention and Coulombic efficiency. This work offers new insights into interface engineering for ASSBs and presents a practical route toward safe, high-performance lithium metal batteries.