The effect of LiAlSiO4 additions on lithium ionic conductivity of garnet Li6.75La3Zr1.75Nb0.25O12 prepared by solid-state synthesis

摘要

LiAlSiO4 (LAS) was added to Li6.75La3Zr1.75Nb0.25O12 (LLZNO) to improve its lithium ionic conductivity for the first time. After the addition of 1 wt% LAS, the lithium ionic conductivity of LLZNO increased from 1.21 x 10(-4) S cm(-1) to 6.93 x 10(-4) S cm(-1) at room temperature (25 degrees C). The relative density also increased from 80% to 94% and the critical current density (CCD) has been improved. Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) results showed that the addition of LAS improved the grains connectivity and reduced the grain boundary resistance, which increased Li+ movement between grains.