Enhanced ionic conductivity of Li1.3Al0.3Ti1.7(PO4)3 under the influence of graphene oxide

Abstract

As a new type of clean and efficient energy storage device, lithium-ion batteries have been widely used in electronic products, electric vehicles, and other fields, and the accompanying safety issues are of increasing concern. Therefore, solid-state lithium-ion conductors have become a current research hotspot. This paper used graphene oxide material to design and prepare Li1.3Al0.3Ti1.7(PO4)3 solid electrolytes by the co-precipitation method and performed some relevant characterizations. The results showed that the addition of graphene oxide optimized the electrolyte structure improved the density of the powder, promoted grain growth, improved the transport path of lithium ions, and thus increased the total ionic conductivity. The optimal doping ratio was 0.5 wt%, and the total ionic conductivity reached the maximum of 2.42 × 10−4 S/cm. Compared to pure Li1.3Al0.3Ti1.7(PO4)3, the ionic conductivity increased by 154% after using the graphene oxide. It is believed that larger grains, fewer grain boundaries, and denser microstructure resulted in a less distorted migration pathway for lithium ions. Under the influence of graphene oxide, Li1.3Al0.3Ti1.7(PO4)3 exhibited better air stability than pure Li1.3Al0.3Ti1.7(PO4)3 electrolyte. The electrolyte prepared in this study showed great application potential in all-solid-state batteries.