Crystal structure, stability and Li superionic conductivity of pyrochlore-type solid electrolyte Li 2− x La (1+ x )/3 Nb 2 O 6 F: a first-principles calculation study

Recently, a new oxide-type solid electrolyte (SE) for all-solid-state Li ion batteries, pyrochlore-type Li 2− x La (1+ x )/3 Nb 2 O 6 F (LLNOF), was reported to exhibit a Li + superionic conductivity of 3.9 × 10 −3 S cm −1 at room temperature.