Influence of Liquid Solutions on the Ionic Conductivity of Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolytes

Hydrothermal synthesis is used to successfully prepare Li1.3Al0.3Ti1.7(PO4)(3) (LATP) solid electrolytes with high lithium-ion conductivity, typically being 0.213 mS cm(-1). The best calcination and sintering temperatures are optimized to be 900 and 1075 degrees C, respectively. The solvent effects on conductivity and microstructure of LATP in water, ethanol and acetone are investigated by using impedance spectroscopy and scanning electron microscopy. The conductivity of LATP in water reaches 1.167 mS cm(-1). In ethanol, the conductivity of LATP is 0.464 mS cm(-1). There is no significant change in acetone. The structural stability of LATP after immersing in liquid solutions is verified by X-ray diffraction and Raman spectroscopy. It is found by infrared spectroscopy that the change in conductivity is related to the adsorbed OH bond, and the reason for the increase in conductivity is discussed.