Characterization of garnet-type Li6SrLa2Bi2O12 ceramic electrolyte for all-solid-state Li-ion batteries

Abstract

We investigated electrochemical properties of garnet-type Li6SrLa2Bi2O12 (LSLBO) ceramic electrolyte for all-solid-state Li-ion batteries. Hot pressing at 750 °C was applied for the densification of LSLBO and the relative density of obtained sample reached 94 %. Hot-pressed LSLBO showed bulk and total ionic conductivity of 1.8 × 10−4 S cm−1 and 1.1 × 10−4 S cm−1, which is much higher than sintered LSLBO by a conventional furnace sintering and spark plasma sintering reported in previous works. Cyclic voltammogram of LSLBO showed the electrochemical stability at the operating potential for most cathode materials for Li-ion batteries. It was found that LSLBO has a certain degree of thermal compatibility with LiCoO2 cathode up to about 700 °C. The obtained results indicates the possibility of LSLBO for the application to catholyte in oxide-based all-solid-state batteries.