Effect of microstructure on the conductivity of a NASICON-type lithium ion conductor

Sintering temperature is used to control the microstructure of Li1 + x + yAlxTi2 − xSiyP3 − yO12 (x = 0.3, y = 0.2), a NASICON-type glass-ceramic. Scanning Electron Microscope imaging, X-Ray Diffraction, and Electrochemical Impedance Spectroscopy are employed to show that increase in sintering temperature increases conductivity while generating secondary crystalline phases. Total conductivity is as high as 3.81 × 10−4 S cm−1 for sintering temperatures above 1000 °C. Crystallization of dielectric phases places the optimal sintering temperature in the 900 °C to 1000 °C range. Thermal analysis of the glass precursor reveals the glass transition, and crystallization temperatures.