Effect of Li2O–Al2O3–GeO2–P2O5 glass crystallization on stability versus molten lithium

Abstract

Glass and glass-ceramic NASICON-type electrolytes of Li1.5Al0.5Ge1.5(PO4)3 composition were obtained by melt quenching and glass crystallization, respectively. The stability of the solid electrolytes to molten metallic Li was studied by immersing the samples and holding them at 230 °C for 72 h. Li|glass|Li and Li|glass-ceramics|Li electrochemical cells were assembled and their resistance was measured by impedance spectroscopy at 200 °C for 9 days. It was established that, unlike the glass, the glass-ceramics did not change in its phase composition and molecular structure after the tests. It is shown that Li1.5Al0.5Ge1.5(PO4)3 glass-ceramics is chemically stable in contact with metallic Li. © 2019 Elsevier B.V.