Mechanically‐Driven Reconstruction of Lithium Metal for Stable All‐Solid‐State Batteries

ABSTRACT Dendrite growth at lithium‐metal anode remains a critical bottleneck in sulfide‐based all‐solid‐state batteries (ASSBs). Current approaches often rely on alloy anodes that compromise energy density or artificial interlayers, introducing additional processing complexity. Herein, we show that accumulated deformation imposed by repeated folding and rolling mechanically reconstructs commercial Li from surface to bulk, replacing a rough carbonate‐rich surface and mixed texture with a refined oxide‐passivated surface and a strongly Li(200)‐preferred texture. At low and medium folding degrees, surface refinement and renewal of the native passivation layer improve solid‐solid contact and interfacial Li‐ion transport, but remain insufficient to prevent short circuiting, whereas high‐degree reconstruction drives texture homogenization, reduces spatial variations in local interfacial response, and synchronizes Li recession and advancement across the rigid Li | solid‐state electrolyte interface. The synchronous interface motion suppresses differential recession and void formation during stripping, while mitigating dendritic Li growth during plating. As a result, Li | LPSCl 1.5 | NMC811 full cells achieve 79.3% capacity retention after 1000 cycles at C/2 rate, support 7.4 mA h cm −2 operation with 0.05% decay per cycle, and cycle stably below 0.5 MPa. These findings establish mechanical reconstruction as a direct materials‐level strategy for stabilizing Li metal in sulfide‐based ASSBs.