Abstract
The hollow spherical Li4Ti5O12 powders are prepared by hydrothermal method assisted with NH4HCO3 as structure-directing agent, using lithium acetate dihydrate and tetrabutyl titanate, as the main raw materials. The structure, diameter and profile of the powders are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performances are characterized by battery testing system and electrochemical workstation. The results show the spherical structure of hollow lithium titanate with cluster surface could be obtained by adding 40mmol ammonium bicarbonate. At 0.1C charge-discharge cycles rate, the first discharge capacity of hollow spherical materials is 176.4 mA h g-1. As the charge-discharge rate increases (from 0.1 C to 20 C), the capacity retention rates in 10 charge-discharge cycles are 98.4％, 97.8％, 99.7％, 97.5％, 98.7％, 98.0％ and 96.2％.
基金项目
authors wish to thank the financial support of the National Natural Science Foundation of China(No. 51072162)
NETL
NSTL
万方数据