Synthesis, sintering and electrical properties of Li1+xGdxZr2-x(PO4)3 solid electrolytes for Li-ion batteries

In this study, the electrical characteristics of spark plasma sintered Li1+xMxZr2-x(PO4)3 solid electrolytes, underlining the impacts of gadolinium (Gd) substitution on lithium-ion battery performance in comparison to conventionally sintered samples. The samples with different amounts of Gd (x= 0.1, 0.2, and 0.3) were sintered by both SPS and conventional methods and characterized using advanced techniques, including field emission scanning electron microscopy (FESEM) for microstructural analysis, X-ray diffraction (XRD) for phase detection, and energy-dispersive X-ray spectroscopy (EDS) for elemental analysis. A significant improvement in densification and a subsequent reduction in porosity are observed in the SPSed samples, which is the main reason for their enhanced structural integrity. However, this increase in densification is accompanied by a complex relationship in which the presence of Gd may hinder ionic transport compared to conventionally sintered samples. Optimizing the Gd content to balance ionic conductivity and structural stability, which supports the development of solid electrolytes for lithium-ion battery applications, was emphasized.