摘要
以醋酸锂和钛酸四丁酯为原料、冰醋酸和无水乙醇为水解抑制剂和溶剂,采用溶胶-凝胶法经高温烧结制备了纳米Li4Ti5O12负极材料,系统研究了烧结工艺对材料组成、结构和电化学性能的影响。研究表明,烧结温度是影响材料性能的最主要因素,恒温时间次之。采用两步烧结法,将所得前驱体以5℃/min的速率升温到600℃,保温6 h,然后升温至750～850℃,保温1～10 h,所制备的Li4Ti5O12结晶程度高,粒径在500 nm左右;在1～2.5 V之间充放电,0.2 C、1 C、5 C和10 C倍率下首次放电比容量分别达到168.6 mAh/g、155.1 mAh/g、139.4 mAh/g和121.1 mAh/g。
Nano-Li4Ti5O12 anode material was prepared after sintering at high temperature by sol-gel method, using lithium acetate and terbutyl titanate as starting materials, acetic acid as hydrolyzing depressor and anhydrous ethanol as solvent. Systemic study was put up on the effect of sintering technics upon the composing, structure and electrochemical capability of the material. According to the investigation, sintering temperature was the main factor that affected the capability of the material, and heating time took second place. Two-step sintering technique was adopted that the precursor was heat up to 600 ℃ at the speed of 5℃/min and been keeping for 6 h, firstly. Then it was heat up to 750-850 ℃ for 1-10 h. The Li4Ti5O12 gained was well crystallized and had the diameter around 500 nm. From 1.0 V to 2.5 V （vs.Li）, the Li4Ti5O12 delivered 168.6 mAh/g, 155.1 mAh/g, 139.4mAh/g and 121.1 mAh/g at 0.2 C, 1 C, 5 C and 10 C, respectively.
出处
《电池工业》
CAS
2011年第5期278-283,共6页
Chinese Battery Industry
