Synthesis of Oxide-Based Composite Solid Electrolyte for Lithium Batteries /

Abstract

One of the most electrifying and interesting supporting components for the advancement of next-generation lithium batteries is a solid-state electrolyte. Oxide-based solid electrolytes are gaining popularity among researchers owing to their great stability, although they have inadequate ionic conductivity due to high grain boundary resistance. In this work, a novel oxide-based ternary composite (AlPO4-SiO2-Li4P2O7) electrolyte is synthesized via a conventional solid-state process with excellent water stability and high ionic conductivity. The crystallographic structure of ternary composite is confirmed using X-ray diffraction and has a significant effect on ionic conductivity. The thermogravimetric analysis result shows a 22.26 wt.% loss in the region of 25 °C to 900 °C due to the degradation of volatile constituents including nitrates, chlorides, and water. BET results revealed that the material is compact and dense and having low porosity and surface area. The morphological assessment is carried out using scanning electron microscopy to observe the growth of grains. The Raman and Fourier transformed infra-red spectroscopies are used to scrutinize the structural and functional group analysis of the solid-state electrolyte. Electrochemical impedance spectroscopy is used to evaluate ionic conductivities. The ternary composite sintered at 900 °C has shown ionic conductivity of 2.21×10-4 S cm-1 at ambient temperature. These findings suggest that a solid electrolyte composed of ternary composites could be a credible candidate for lithium batteries.