Preparation of high density garnet electrolytes by impregnation sintering for lithium-ion batteries

Abstract

The conductivity of solid state electrolyte is closely connected with its chemical composition, crystal structure and density. High density Ta-doped Li7La3Zr2O12 (LLZTO) plates were synthesized by impregnation sintering. The density of electrolyte plates increased when the impregnating solution concentration increased from 5 to 35%. The LLZTO electrolyte plates showed a highest ionic conductivity of 6.47 × 10−4 S/cm when the impregnating solution concentration was 35%. The LLZTO electrolyte plates presented a highest relative density of 97% when the impregnating solution concentration was 40%, meanwhile, the activation energy of this electrolyte plate was calculated to be 0.35 eV, lower than the other samples.