(北京有色金属研究总院 动力电池研究中心，北京100088)
摘 要: 以偏钛酸锂(Li2TiO3)和二氧化钛(TiO2)为原料，采用固相法合成钛酸锂(Li4Ti5O12)，通过XRD、SEM和电化学测试等方法对合成的钛酸锂材料的结构、形貌和电化学性能进行表征，同时研究一次颗粒长大规律和反应机理。结果表明：Li2TiO3是传统固相法合成Li4Ti5O12的中间产物，用Li2TiO3为原料在720、750 ℃保温10 h可合成纯的Li4Ti5O12，制备的一次颗粒粒径分别为270、278 nm，较用Li2CO3和TiO2为原料合成纯相的温度更低，一次颗粒粒径更小。反应期间，一次颗粒粒径随着反应分数的增大呈快速增长势头；反应结束后，一次颗粒粒径增长缓慢。750 ℃合成的Li4Ti5O12在充放电倍率为0.1C、1C、5C、9C时，比容量分别为170、164、149、126 mA？h/g，在0.1C时循环200次容量保持率大于97%，显示制备的Li4Ti5O12具有良好的电化学性能。
关键字: 偏钛酸锂；钛酸锂；固相法；电化学性能
（Research and Development Centre for Vechicle Battery and Energy Storage,
General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The Li4Ti5O12 material was prepared by solid-state method with Li2TiO3 and TiO2 as the source of titanium and lithium. The crystalline structure，morphology and electrochemical performances of the samples were investigated by X-ray diffraction, scanning electron microscope and charge discharge test, and the growing regularity of primary particles and the reaction mechanism were studied at the same time. The results show that Li2TiO3 is an intermediate product for traditional method, pure Li4Ti5O12 materials are prepared at 720 and 750 ℃ for 10 h using Li2TiO3 as raw material, and the sizes of prepared fine primary particles are 270 and 278 nm, respectively, which are smaller than those using Li2CO3 and TiO2 as raw materials, and the temperature of pure phase Li4Ti5O12 obtained is lower. With increasing conversion of reaction, the size of primary particles increases rapidly, then increases slowly after the reaction finishes. The initial specific discharge capacities of Li4Ti5012 synthesized at 750 ℃ and the charge-discharge rate of 0.1C, 1C, 5C and 9C are 171, 164, 149 and 126.7 mA？h/g, respectively. After 200 cycles at 0.1C, it remains more than 97% of the initial specific discharge capacity, exhibiting excellent electrochemical performance.
Key words: Li2TiO3; Li4Ti5O12; solid-state method; electrochemical performance
