Accelerated Short Circuiting in Anode?Free Solid?State Batteries Driven by Local Lithium Depletion

“Anode-free” solid-state batteries (SSBs), which have no anode active material, can exhibit extremely high energy density (?1500 Wh L?1). However, there is a lack of understanding the lithium plating/stripping mechanisms at initially lithium-free electrolyte (SSE) interfaces because excess metal often used. Here, it demonstrated that commercially relevant quantities (>5 mAh cm?2) be reliably plated moderate current densities (1 mA using sulfide SSE Li6PS5Cl. Investigations mechanisms, in conjunction with cryo-focused ion beam (FIB) imaging, synchrotron tomography, and phase-field modeling, reveal cycling stability these cells fundamentally limited by nonuniform presence during stripping. Local depletion causes isolated regions toward end stripping, decreasing electrochemically area resulting local void formation. This accelerates subsequent filament growth short circuiting compared to lithium-excess cells. Despite this degradation mode, shown anode-free comparable Coulombic efficiency cells, improved resistance achieved avoiding through retention thicker interface. These new insights provide foundation for engineering future high-energy SSBs.