Enhancement of ionic conductivity and fracture toughness by infiltrating porous Li0.33La0.56TiO3 pellets

Although solid-state lithium electrolytes have the potential to reduce the safety issues associated with organic liquid electrolytes , disadvantages such as low total conductivity, large interface impedance, and delamination of the interface due to cyclic stress still need to be addressed. The solid-state lithium-ion conductor Li 0.33 La 0.56 TiO 3 (LLTO) was prepared via a hydrothermal route by using CTAB as templates in this paper. Perovskite LLTO with micro-porous channels was obtained and the total conductivity is comparable to the non-porous LLTO. Porous LLTO pellets are infiltrated with the non-porous LLTO precursor solution, and the total conductivities of the infiltrated porous LLTO are all higher than those without infiltration. After infiltration, the porous LLTO calcined at 600 °C achieves the highest total conductivity, 7.88 × 10 −5  S/cm. The fracture toughness of the infiltrated LLTO is higher than that of the non-porous LLTO. The results demonstrate a new way to prepare solid-state lithium-ion conductors with high ionic conductivity and great tolerance to cyclic stress.