Stabilization of the cubic, fast-ion conducting phase of LiLaSnO garnet by gallium doping.

All-solid-state batteries present promising high-energy-density alternatives to conventional Li-ion chemistries, and Li-stuffed garnets based on LiLaZrO (LLZO) remain a forerunner for candidate solid-electrolytes. One route to access fast-ion conduction in LLZO phases is to stabilize the cubic LLZO phase by doping on the Li sites with aliovalent ions such as Al or Ga. Despite prior attempts, the stabilization of the cubic phase of isostructural LiLaSnO (LLSO) by doping on the Li sites has up to now not been realised.