Low Temperature Sintering of Garnet-type Li-La-Zr-O Solid Electrolytes Using Sintering Additive

Abstract

The garnet-type Li₇La₃Zr₂O₁₂ (LLZ)-based oxides have attracted attention as a solid electrolyte for next-generation all-solid-state lithium secondary batteries because of its relatively high ionic conductivity and high chemical stability toward Li metal. Producing densified garnet-type solid electrolytes at rather lower sintering temperature is an important target, which can prevent not only the lithium loss (controlling chemical stoichiometry) but also make it more compatible with cathode electrode materials. The use of sintering additives for enhancing the densification and microstructure of high ionic conductive garnet-type solid electrolytes is reviewed. Sintering additives can modify the grain and grain boundary, both contributing to the improving of the chemical and electrochemical properties of garnet-type solid electrolytes.