Preparation of Spherical Nanocrystal LiFePO_4 and Li_4Ti_5O_(12) and Investigation of the LiFePO_4/Li_4Ti_5O_(12) Cell

The spherical nanocrystal LiFePO4/C and Li4Ti5O12/C are synthesized via controlled crystallization and outer gel technics,respectively.XRD,SEM,BET testing and the determination of the electrochemical properties show that the LiFePO4/C and Li4Ti5O12/C particles are spherical nanocrystals.The products exhibit great specific surface area.The tap-densities of spherical LiFePO4/C and Li4Ti5O12/C powders are as high as 1.25 and 1.71g/cm3,respectively.The initial discharge specific capacities of the LiFePO4/C and Li4Ti5O12/C reach 144.0 and 144.2mAh/g at 1C rate.The materials also exhibit excellent cycle performance.A 1.8 V lithium-ion battery composed of LiFePO4/C and Li4Ti5O12/C shows a quite flat operating voltage of 1.8V with excellent cycleability.