Low temperature synthesis of Ga-doped Li7 La3 Zr2 O12 garnet-type solid electrolyte by mechanical method

Synthesis of Li6.25 Ga0.25 La3 Zr2 O12 (LLZO-Ga) solid electrolyte powder granule for all solid-state battery was investigated by applying mechanical processing of the raw powder materials adding LiF-BaF2 as a flux. The LLZO-Ga of highly crystalline was synthesized by the mechanical method using an attrition-type mill without any extra-heat assistance. When 10 mass% of LiF-BaF2 was added to the raw powder materials and 28 min processed, LLZO-Ga powder was favorably synthesized and granulated at the chamber temperature of 284 °C. The ionic conductivity of the sintered body of the LLZO-Ga granules was evaluated by impedance measurement. It revealed the high ionic conductivity of σtotal 1.0 × 10−3 S/cm. It suggests that the formation of LLZO-Ga/BaZrO3 grain boundary contributes to higher ionic conductivity adding to the high crystalline phase of LLZO-Ga.