Microstructural effects on the superionic conductivity of a lithiated glass-ceramic

Three different formulations of 14 Li2O·9 Al2O3·38 TiO2·39 P2O5 composition (LATP) were melted, cast and crystallized. As-cast glass was characterized by differential scanning calorimetry which exhibited a distinct and strong exothermic peak around 680 °C. The peak was attributed to the crystallization of the glass. The crystallized glass (glass-ceramic) was further characterized by X-ray diffraction which showed the existence of Li1 + xAlxTi2 − x(PO4)3 (x ⋍ 0.3)as the primary phase mixed with a small concentration of AlPO4 and an unidentified phase. The scanning electron micrographs revealed the presence of the primary crystalline phase with an average grain size of 1 μm. Electrical characterization by AC impedance spectroscopy revealed grain and grain boundary contributions to the total conductivity. The effect of specimen processing parameters on conductivity is also investigated and discussed.