Influence of Li3PO4 addition on properties of lithium ion-conductive electrolyte Li1.3Al0.3Ti1.7(PO4)3

The sintered Li1.3Al0.3Ti1.7(PO4)3 pellets with different mole fractions of Li3PO4 were prepared by sol-gel method. The structure, surface morphology, electrochemical window, ionic conductivity and activation energy of the sintered pellets were studied by X-ray diffraction, scan electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The results show that all the sintered Li1.3Al0.3Ti1.7(PO4)3 pellets with different mole fractions of Li3PO4 have similar X-ray diffraction patterns. The sintered Li1.3Al0.3Ti1.7(PO4)3 pellet with Li3PO4 shows a lower porosity and is denser than the one without Li3PO4. The addition of Li3PO4 has a large effect on the porosity and density of the sintered Li1.3Al0.3Ti1.7(PO3)4 pellet, and little effect on its electrochemical window. Among the sintered Li1.3Al0.3Ti1.7(PO3)4 pellets with different mole fractions of Li3PO4, the one with 1% Li3PO4 shows the activation energy of 0.314 2 eV and the highest ionic conductivity of 6.15×10−4 S/cm.