Nanoscale Synthesis of Li_1.3Al_0.3Ti_1.7(PO₄)₃ Solid-State Lithium Ion Battery Electrolyte: A Structural and Ionic Conductivity Study

Abstract

Nanoscale-featured Li-based NASICON-type solid-state electrolytes (SSEs) are an emerging material that overcomes the demerits such as conductivity and stability of other organic-and inorganic-based electrolytes. However, syntheses of these types of SSEs require higher temperatures, which is a challenging task to reduce energy consumption to date. Hence, this work aims to prepare a nanosized Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP) SSE at relatively low sintering temperature. LATP is prepared by a modified sol−gel method using a mineralizer (conc. HNO 3 ) and citric acid. The size of the synthesized LATP was reduced to the nanolevel using the ball milling process to achieve high relative density at low sintering temperature. The assynthesized LATP nanoparticles (NPs) were characterized by using phase compositions and morphological analyses. The LATP NPs were sintered at different sintering temperatures and for different soaking times. The maximum relative density (93.36%) and high ionic conductivity (6.39 × 10 −4 S/cm) were achieved for the sample sintered at 825 °C for 6 h (S-LATP-825-6), which is found to be a lower sintering temperature than in the previous reports. The storage stability results showed that S-LATP-825-6 exhibits good ionic conductivity retention even after 30 days of storage under natural environmental conditions.