Preparation of nanoporous β-Li₃PS₄ solid electrolyte with high ionic conductivity by wet chemical method

Abstract

The β-Li3PS4 solid electrolyte with high ionic conductivity and low activation energy was prepared by wet chemical method and stepwise heated to remove tetrahydrofuran molecules from the precipitate. The morphology, structure and phase composition of the products at different treatment stages were studied by means of simultaneous thermal analysis, X-ray diffraction, scanning electron microscopy, Raman spectroscopy, N2 adsorption/desorption and AC impedance spectroscopy, and the electrochemical performance of β-Li3PS4 solid electrolyte were analyzed. The results show that the specific surface area of the nanoporous β-Li3PS4 solid electrolyte prepared by this method is 28.3m2·g-1 and its average pore diameter is about 23nm. Electrochemical characterization shows that the ionic conductivity of the electrolyte at 20℃ is 1.84×10-4 S·cm-1, the activation energy is 0.343eV, and the electronic conductivity is 1.3×10-8S·cm-1. In addition, the electrolyte has excellent electrochemical stability and good compatibility with the lithium anode.

Keywords

• wet chemical method
• tetrahydrofuran
• solid electrolyte
• nanoporous β-li₃ps₄