Fast Lithium-Ion Conducting Garnet-Like Electrolytes for Potential Application in Lithium Ion Batteries

Abstract

In this paper, we report the effect of Y-doping for Nb in the garnet-like Li5La3Nb2O12 on Li-ion conductivity. The phase formation, microstructure and electrical conductivity studies were done using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), 7Li nuclear magnetic resonance (Li-NMR) and AC impedance spectroscopy. The formation of cubic garnet-like structure was observed for x up to 0.25 and additional impurity peaks were observed above x = 0.25 in Li5La3Nb2-xYxO12-δ. 7Li MAS NMR exhibits a single peak close to a chemical shift value of 0 ppm with respect to LiCl which could be due to the fast conduction of Li ions. Lithium ion conductivity of 1.34 x 10-5 and 1.44 x 10-5 Scm-1 was observed for x = 0.05 and 0.1 members, respectively at 23 °C in air.