化学镀Ni改性Li_4Ti_5O_(12)材料的制备及其电化学性能研究  

Synthesis of Modified Li_4Ti_5O_(12) Anode Material with Electroless Plating Nickel and Its Electrochemical Properties

作　　者：李军[1] 黄际伟[1] 周燕[1] 陶熏[1] 

机构地区：[1]广东工业大学轻工化工学院,广东广州510006

出　　处：《稀有金属》2014年第2期224-229,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(20672023);广州市科技计划项目(2011Y1-00010);广东省科技计划项目(2012B050100010)资助

摘　　要：为提高Li4Ti5O12的电化学性能和防气胀性能，结合固相法并用化学镀金属Ni对样品进行表面修饰改性，制备了Li4Ti5O12／Ni复合材料。使用x射线衍射（XRD）、Raman光谱、扫描电镜（SEM）对样品进行了物相分析和形貌表征，结果显示：合成的样品具有单一的尖晶石结构，Li4Ti5O12／Ni复合材料和Li4Ti5O12在拉曼光谱图上具有相同的频率振动特性，说明化学镀法表面修饰Li4Ti5O12／Ni复合材料并没有改变纯相Li4Ti5O12的结构，且样品的颗粒大小均匀、形状规则，颗粒尺寸在0．5～1．0μm范围内。采用充放电测试、循环伏安和交流阻抗对样品的电化学性能进行表征，结果表明：Li4Ti5O12／Ni复合材料在1C和5c倍率下首次放电比容量分别为149．8和132．5mAh·g-1，循环50次后分别为144．1和124．0mAh·g-1，容量保持率为96．2％和93．6％，表现出良好的倍率性能和循环性能，Li4Ti5O12／Ni的阻抗值明显小于纯相Li4Ti5O12。In order to improve electrochemical and anti-flatulence properties of Li5 Ti5 O21, microscopy Li4 Ti5 O12/Ni （LTO/Ni） anode materials were prepared through high temperature solid-state reaction by modifying the surface of samples via facile electroless deposi- tion of Ni. The microstructure and morphology of the prepared samples were characterized by X-ray diffraction （XRD） , Raman spec- troscopy and scanning electron （SEM）. The results showed that the samples possessed spine structure, it could be observed that the Li4Tis On/Ni composite and Li4Ti5 O12 shared the same vibrating frequency, which indicated that the addition of Ni had no effect on the structure of pure Li4Ti5O12, and the particles were uniform and were regularly shaped within 0.5 - 1.0 la,m. Electrochemical properties of the samples were evaluated by the charging and discharging tests, cyclic voltammograms and AC impedance spectroscopy. The re- suits indicated that the Li4Ti5O12/Ni composite exhibited good rate performance and cycle performance. At the discharge rate of 1C and 5C, their specific capacities were 149.8 and 132.5 mAh.g-1 and remained at 144. 1 and 124.0 mAh.g-1 respectively after 50 cycles, with a retention rate of capacity of 96.2% and 93.6% indicating good rate capacity and cycle performance. And the resistance value of Li4Ti5O12/Ni was much lower than that of pure Li4Ti5O12 material.

关 键 词：锂离子电池 负极材料 LI4TI5O12 NI 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]