Characterization of the Li-ionic conductivity of La(2/3 − x)Li3xTiO3 ceramics used for all-solid-state batteries

• La(2/3) − xLi3xTiO3 with x = 0.11 (LLTO11) ceramics was prepared by a dMA method.
• The increase in the ionic conductivity of LLTO11 ceramics was obtained by quenching.
• The Li-ionic conductivity of LLTO11 reached values as large as 1.8 × 10− 3 S·cm− 1
• LLTO11-based batteries possessed a charging capacity of 3 μAh/(cm2 · μm) at 1.6 V.

With the aim to improve the ionic conductivity of perovskite materials used for all-solid-state batteries, La(2/3) − xLi3xTiO3 with x = 0.11 (LLTO11) ceramics was prepared by a double mechanical alloying method. The influence of thermal treatments (furnace-cooling, SC and quenching, QC) on the crystalline structure and Li-ion conductive properties of the LLTO ceramics has been studied by X-ray powder diffraction (XRD), Raman scattering and impedance spectroscopy. XRD patterns of SC-samples exhibited a doubled perovskite with a tetragonal structure, whereas those of quenched samples indicated a simple cubic perovskite. The increase in the ionic conductivity of the LLTO11 ceramics was attributed to the disordered morphology that has promoted 3D-conductive mechanism. At room temperature, the grain and grain-boundary conductivities of the quenched LLTO11 ceramics reached values as large as 1.8 × 10− 3 S·cm− 1 and 7.2 × 10− 5 S·cm− 1, respectively. All-solid-state batteries made from the LLTO11 solid-state electrolyte combining with LiMn2O4, and SnO2 thin films as cathode and anode, respectively, possessed a charge-discharge efficiency of ~ 61% and a charging capacity of ~ 3.0 μAh/(cm2 · μm) at a voltage of 1.6 V.