New lithium-ion conducting perovskite oxides related to (Li, La)TiO3

We describe the synthesis and lithium-ion conductivity of new perovskite-related oxides of the formulas, LiCa1,65#0,35Ti1,3B1,7O9 (B = Nb, Ta) (I, II), LiSr2Ti2,5W0,5O9 (III) and LiSr1,65#0,35Ti2,15W0,85O9 (IV). Oxides I and II crystallize in orthorhombic (GdFeO3-type) structure, while oxides III and IV possess cubic symmetry. All of them exhibit significant lithium-ion conduction at high temperatures, the highest conductivity of ~ 10–2 S/cm at 800C among the oxides is exhibited by the composition IV. The results are discussed in the light of previous work on lithium-ion conducting perovskite oxides containing d 0 cations.