LiF-doped Li1.3Al0.3Ti1.7(PO4)3 superionic conductors with enhanced ionic conductivity for all-solid-state lithium-ion batteries

The Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid electrolyte powders doped with LiF are successfully synthesized by spray-drying and calcination methods, and the corresponding physicochemical properties are investigated using X-ray diffraction, a field emission-scanning electron microscope, and an X-ray photoelectron spectroscope. The results show that the LiF-doped LATP (LATP-0.15) solid electrolyte presents excellent performance compared with the pure LATP solid electrolyte when the weight ratio of LiF vs. LATP maintains at 0.15, in which the LATP-0.15 solid electrolyte possesses a higher compacted density of 2.887 g cm−2 and a higher ionic conductivity at room temperature of 1.767 × 10–4 S cm−1 with lower activation energy of 0.276 eV. Furthermore, the assembled LiCoO2/LATP-0.15/Li coin cell delivers a relatively high discharge specific capacity of 136.7 mAh g−1 at 0.1 C after only five active cycles and maintains up to 97.77% of capacity retention ratio after 290 cycles. Those results indicate that the as-prepared LATP-0.15 solid electrolyte may be employed to be a potential candidate in the future all-solid-state lithium-ion batteries.