Ionic and electronic conductivity of solid electrolyte Li0.5La0.5TiO3 doped with LiO2-SiO2-B2O3 glass

Abstract

The LiO2-SiO2-B2O3 (LBS) glass doped solid electrolyte Li0.5La0.5TiO3 (LLTO) ceramics were prepared by solid-state reaction method. The results show that the samples present mainly tetragonal perovskite structure and grain size increase with glass content increases. The frequency dependent AC conductivity shows two plateaus that correspond to the bulk and grain boundary responses associated with two semi-circles observed in AC impedance spectrum. The maximum bulk ionic conductivity appeared at 1.0 wt% glass addition calculated by equivalent circuit at a value of 1.12 × 10−3 S/cm, which is nearly 1.7 times compared to pure LLTO at room temperature. The overall electronic conductivity is about 10−9 S/cm calculated from a long time leakage current measurement, which is 6 orders of magnitude lower than the ionic conductivity σbulk. These results would be helpful for us to adjust and control the conductivity of glass added solid electrolyte composite for use of all-solid-state lithium batteries.