Solid-state sintering is the most used synthesis process to produce solid-state electrolytes. Powders of LAGP precursors, including oxides like GeO and AlO, are mixed, calcinated and densified at high temperature (700 - 1200 °C) and for long times (12 hours). Sintered LAGP is characterized by high crystalline quality, large grains, a compact microstructure, and high density, even if negative side effects such as loss of volatile lithium compounds and formation of secondary phases should be avoided while the material is kept at high temperature.
The sintering parameters affects LAGP microstructure and purity and, ultimately, its ionic conductivity and conduction performances.