Facile synthesis of NASICON-type Li1.3Al0.3Ti1.7(PO4)(3) solid electrolyte and its application for enhanced cyclic performance in lithium ion batteries through the introduction of an artificial Li3PO4 SEI layer

摘要

The pure Li1.3Al0.3Ti1.7(PO4)(3) (LATP) ceramic powders with uniform distribution have been successfully synthesized with CO(NH2)(2) as a molten flux at a relatively lower temperature compared to conventional methods. The influences of the molar ratio of molten CO(NH2)(2) to reaction precursor, calcination temperature for the LATP powders and the sintering temperature for the LATP pellets are investigated; the pellet with the highest total conductivity of 7.02 x 10(-4) S cm(-1) at room temperature is obtained. In addition, in view of the instability between LATP and metallic lithium, we introduce an artificial Li3PO4 SEI (solid electrolyte interphase) layer to block the contacts between them. The results of galvanostatic charge-discharge measurement show that the as-assembled battery delivers an excellent capacity retention ratio of 95.2% at 0.1C rate after 50 cycles, which is much higher than untreated samples. We conclude that adding an artificial Li3PO4 SEI layer is an effective way to improve the electrochemical property of solid state lithium ion batteries (LIBs) with LATP as an electrolyte.