Effect Temperature for improving the Li-ion conductivity of Li7La3Zr2O12

Abstract

This study investigates the dissociation behavior of water-soluble salts of Li and La and the unique behavior of Zr sources, resulting in the generation of Li+, La3+, and Zr4+ ions in aqueous solutions. The specific conductivity of calcined SG1 and SG2 displays temperature-dependent variations, with SG1 consistently exhibiting higher conductivity (2.08 x 10-4 S/cm) across the temperature range. The closed-packed structure facilitates the controllable mass transfer of lithium, enhancing ionic conductivity. The constructed LiFePO4/LLZO/AC device using these electrolytes demonstrates an impressive energy density of 1.95 Wh/kg and a power density of 144.92 W/kg, showcasing an excellent solid electrode-electrolyte interphase. Over 10,000 cycles, cyclic stability, with an average performance of 86%, underscores the potential of LLZO as a solid electrolyte for advanced energy storage devices. The sol-gel synthesis and densification strategy is a simple and effective method for obtaining lithium-rich LLZO electrolytes. The enhanced ionic conductivity and electrochemical performance of the solid-state device emphasize the practical viability of this approach, contributing to the sustainable development of advanced energy storage technologies.