Lithium Ion Conductivities of Solid Electrolytes Prepared by Low-temperature Heat Treatment of Amorphous Materials in the Li<sub>2</sub>O-Al<sub>2</sub>O<sub>3</sub>-GeO<sub>2</sub>-P<sub>2</sub>O<sub>5</sub> System for All-solid-state Batteries

Amorphous materials (a-LAGP(x = 0.5)) with the composition of Li1.5Al0.5Ge1.5(PO4)3 were prepared by mechanochemical synthesis method. Crystalline compounds LiGe2(PO4)3-based NASICON-type structure formed heat treatment a-LAGP(x 0.5) at 400–700 °C in air. Solid electrolytes pelletized-type and MgO-modified 700 exhibited lithium ion conductivities on order 10−5–10−4 S cm−1 room temperature. The addition MgO into increased electrical conductivity. Lithium conductors low-temperature amorphous Li2O-Al2O3-GeO2-P2O5 system would be promising as solid for all-solid-state batteries.