Abstract
Investigation of the commercially available Na1.3Al0.3Ti1.7(PO4)3 (NATP) solid electrolyte for Na-ion solid-state batteries (SIBs) application requires a comprehensive understanding of its microstructural, thermal behaviour and electrical properties. In this study, we investigated the solid electrolyte properties of NATP through different spectroscopic techniques, including XRD, SEM, DSC/TGA, Dilatometer, and Impedance Spectroscopy. The impact of sintering temperature on the densification, microstructural and electrical properties was investigated. Both Archimedes and geometric density measurement methods were utilised to determine the relative density (ρr) of the sintered ceramics. Additionally, we investigated the optimum temperature at which the AlPO4 secondary phase is suppressed/minimised for this solid electrolyte. Refinement of the phases present in the NATP was studied using Topas 5 software to provide insight into the crystalline structure of the ceramic. The ionic conductivity studies of the NATP solid electrolyte were found to be in the range of 10− 7 – 10− 8 S/cm at 25°C, and the activation energies were in the range of 0.46 ± 0.35 eV. This study provides a thorough understanding of NATP properties, indicating its potential as a solid electrolyte.