Synthesis and characterization of Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 by wet chemical route

Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 was prepared by wet chemical route. The phase, surface morphology, and electrochemical properties of the prepared powders were characterized by X-ray diffraction, scanning electron micrograph, and galvanostatic charge-discharge experiments. Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 has similar X-ray diffraction patterns as LiMn2O4. The corner and border of Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 particles are not as clear as the uncoated one. The two powders show similar values of lithium-ion diffusion coefficient. When cy-cled at room temperature and 55℃ for 40 times at the charge-discharge rate of 0.2C, Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 shows the capacity retentions of 98.2% and 93.9%, respectively, which are considerably higher than the values of 85.4% and 79.1% for the uncoated one. Both the capacity retention differences between Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 and LiMn204 cycling at room temperature and 55℃ become larger with the increase of charge-discharge rate. When the charge-discharge rate reaches 2C, the capacity retention of LATP-coated LiMn2O4 becomes 8.4% higher than the uncoated LiMn2O4 for room temperature cycling, and it becomes 11.1% higher than the latter when cycled at 55℃.