LaNi5-CNTs复合材料的制备及其应用

Preparation and Application of LaNi_5-CNTs Composite Materials

采用机械球磨法制备LaNi5-CNTs复合储氢材料,并制备AA1400mAh电池。通过扫描电子显微镜(SEM)、X射线衍射(XRD)以及交流阻抗手段对复合材料进行表征,并对复合材料电池进行充放电性能测试。结果表明:复合材料具有CaCu5结构,表面键合了众多的CNTs;碳纳米管的添加使得电极反应电阻减小,合金的表面催化活性增强,交换电流密度增大,微分电容降低,提高了电极高频放电性能,同时使得电极过程中电极表面过程状态变量增加。AA1400mAh电池1C容量达到了1493mAh,高倍率2.3、5C放电容量达1415、1380mAh,比LaNi5母合金电池容量分别高出3.4%、6%、7%。

LaNi5-CNTs composite materials prepared by ball-milling method were fabricated for AA 1400 mAh batteries. X-ray diffraction （XRD）, scanning electron microscope （SEM） and a. c. impedance were used for characterization. The characters of the batteries were investigated by charge/discharge method. The results indicated the composite material possesses a structure of CaCu5 on whose surface a plenty of CNTs is bonded. Adding CNTs decreased the reaction resistance, enhanced surface catalyze activity, increased the exchange current density, reduced the differential capacitance, enhanced discharge performance of the electrode at high frequency, and caused in the increase of state variable of the electrode surface during the electrode process. The AA1400 mAh batteries exhibited a 1 C capacity of 1493 mAh, and the discharge capacity with high rate 2.3 C, 5 C is 1415, 1380 mAh, which is higher than that of LaNi5 batteries by 3.4%, 6% and 70 respectively.