Synthesis of plate-like Li3PS4 solid electrolyte via liquid-phase shaking for all-solid-state lithium batteries

Abstract

The precursor of plate-like Li3PS4 solid electrolyte (75Li2S▪25P2S5, SE (LS)), about 3 μm in length, 500 nm in width, and 100–200 nm in thickness, was successfully prepared from Li2S and P2S5 using ethyl propionate (EP) as a synthetic medium via liquid-phase shaking. Upon evacuating at 170 °C, the precursor decomposed to SE (LS), which exhibited ionic conductivity of about 2.0 × 10−4 Scm−1 at room temperature. SEM observation revealed that the SE (LS) thus obtained had plate-like morphology with dimension of 3 μm in length, 500 nm in width, and 100–200 nm in thickness. Owing to the nanosized SE (LS), an all-solid-state half-cell using composite anode consisting of 90 wt% LiNi1/3Mn1/3Co1/3O2 (NMC) and 10 wt% SE (LS) delivered a high capacity up to 130 mAhg−1(NMC) at the first discharge.