Synthesis and Evaluation of Garnet Type Ga, Al-Doped Llzo Powder for All-Solid State Batteries

Lithium ion secondary batteries have been widely used with high capacity and energy density. Recently, many sorts of lithium batteries have been studied for EV and ESS applications. However, safety issues such as explosion of organic electrolytes have been raised, all-solid state batteries (ASSBs) which do not use organic electrolytes are promising next-generation batteries. Garnet-type solid electrolytes have good advantages with stable in the atmosphere and electrochemical potential window. In this study Ga, Al-doped LLZO materials (Li7-3(x+y)AlxGayLa3Zr2O12) which are cubic single phase were synthesized by Taylor reactor process. The ionic conductivity was investigated according to the contents of Al and Ga doping contents. Furthermore, composite solid electrolyte sheet composed of LLZO and PEO polymer was prepared and evaluated for its properties. ASSBs were fabricated by using composite electrolyte sheet and electrochemical properties were evaluated. Moreover, we describe about the electrochemical effects of the composition of Ga and Al on cell performance in more detail.