A solid solution of a 100Li3PS4·xLi3PO4 electrolyte was easily prepared by liquid-phase synthesis. Instead the conventional solid-state synthesis methods, ethyl propionate used as reaction medium. The initial stage among Li2S, P2S5 and Li3PO4 proved ultraviolet-visible spectroscopy. powder X-ray diffraction (XRD) results showed that formed up to x = 6. At 20, XRD peaks were detected in sample a...