High Li-ionic conductivity of Li29Zr9Nb3O40 ceramic sintered in oxygen-deficient atmosphere

Abstract

Lithium ion batteries (LIBs) based on solid state electrolytes have attracted much attention for their high safety and energy density. Li29Zr9Nb3O40 powders as Li-ionic conductors were prepared using a sol-gel method in this work, and the related ceramics were sintered in air or in an oxygen-deficient atmosphere in which sample was covered with corundum crucible. All the sintered ceramics are consisted of orthorhombic phase. Li29Zr9Nb3O40 ceramic sintered in oxygen-deficient atmosphere has conductivity of 1.03 × 10−3 S cm−1 at room temperature and has ionic transference number of 0.9996, while the ceramic sintered in air has conductivity of 4.41 × 10−5 S cm−1. The influence of oxygen vacancy on the migration path of Li-ion was discussed. The migration paths of Li-ions between two kinds of Li29Zr9Nb3O40 ceramics were simulated and visualized by method of bond valence site energy with VESTA software.