Lithium Lanthanum Titanate Single Crystals: Dependence of Lithium-Ion Conductivity on Crystal Domain Orientation.

Lithium lanthanum titanate LaLiTiO (LLTO) has the potential to exhibit the highest Li-ion conductivity among oxide-based electrolytes because of the fast Li-ion diffusion derived from its crystal structure. Herein, bulk Li-ion conductivity of up to σ = 4.0 × 10 S/cm at 300 K, which is approximately three to four times higher than that of LLTO polycrystals, was demonstrated using LLTO single crystals, and their dependence on crystal domain orientation was examined.