Effects of Sn substitution on the properties of Li4SiO4 ceramic electrolyte

The aim of this work is to investigate the effects of Sn doping on the structural, thermal, electrical and electrochemical properties of Li4SiO4 synthesized by a sol gel method. The formation of the compound is confirmed by XRD study. Thermal properties of the compounds are measured using DSC analysis while the electrical characteristics are investigated by impedance spectroscopy. The introduction of Sn ions considerably raises the conductivity and improves thermal stability of the Li4SiO4 compound. The compound of Li4Sn0.02Si0.98O4 gives a maximum conductivity value of 3.07 x 10(-5) S cm(-1) at ambient temperature and 130 x 10(-4) S cm(-1) at 500 degrees C. The charge carrier concentration and mobile ion concentration are found to be constant over the temperature range from 303 K to 773 K, while the mobility of ion increases with temperature, implying that the increase in conductivity with temperature is due to increase in ion mobility. Linear sweep voltammetry result show that the Li4Sn0.02Si0.98O4 sample is electrochemically stable in the voltage range of - 53 V to 5.3 V versus a Li/Li+ reference electrode. (C) 2013 Elsevier B.V. All rights reserved.