Ultrafast Synthesis of I-Rich Lithium Argyrodite Glass-Ceramic Electrolyte with High Ionic Conductivity.

Lithium argyrodites are one of the most promising sulfide electrolytes due to their high ionic conductivity and ductile feature. Among them, Li PS I (LPSI) exhibits better stability against Li metal but a rather low ionic conductivity (only ≈10 S cm ) because of the absence of S /I disorder. Herein, argyrodite Li PS I glass-ceramic electrolytes with high iodine content are synthesized using ultimate-energy mechanical alloying method. S /I disorder is successfully introduced into the system by doping LiI during this one-pot process. Determined by Li magic angle spinning nuclear magnetic resonance and ab initio molecular dynamics simulations, the introduction of iodine promotes Li inter-cage jumps, leading to an enhanced long-range Li conducting. The Li PS I glass-ceramic electrolyte (LPSI -gc) possesses high ionic conductivity (2.04 mS cm ) and excellent stability against Li metal. The Li symmetric cell with the LPSI -gc electrolyte demonstrates ultralong cycling stability over 3200 h at 0.2 mA cm . LiCoO /Li PS Cl/Li all-solid-state battery applying LPSI -gc as the anode interlayer also presents prominent cycling and rate performance. This work provides a novel type of electrolyte with high ionic conductivity and stability against Li metal.