电极活性材料Li_4Ti_5O_(12)的制备及其主要影响因素

Preparation and Key Influencing Factors of Li_4Ti_5O_(12) as Electrode Material

在正交试验的基础上考察了烧结温度及时间、锂源对固相合成Li_4Ti_5O_(12)性能的影响.结果表明,烧结温度为最显著影响因素;恰当的温度与时间组合可以制备粒径小、结晶度好的产物,具有良好的电化学性能;硝酸锂为锂源制备的Li_4Ti_5O_(12)具有较好的高倍率充放电能力.以LiNO_3为锂源,空气气氛下800℃烧结12h,所得Li_4Ti_5O_(12)在大电流密度下充放电性能良好,1C、2C、5C时的放电容量分别达到了151、140、115mAh·g^(-1),且具有良好的可逆性.

Effects of sintering temperature, time and the lithium salts on the properties of Li4Ti5O12 synthesized by a solid-state-method were studied based on orthogonal experiments. The results show that sintering temperature is the most principal factor on the performance of Li4Ti5O12. Synthesized at proper sintering temperature with appropriate time, the product will have good electrochemical properties with finer particle size and better crystallinity. The high-rate discharge/charge property of Li4Ti5O12 prepared with LiNO3 is much better. Li4Ti5O12 obgained at the optimum condition, namely preparing with LiNO3 and sintering at 800℃ for 12h, performs well when charged and discharged with high current density. It delivers discharge capacities of 151mAh·g^-1, 140mAh·g^-1 and ll5mAh·g^-1 at the rate of 1C, 2C and 5C, respectively, and shows good reversibility.