铝集流体对锂离子电池正极材料LiNi_(0.5)Co_(0.2)Mn_(0.3)O_2性能的影响

Effect of aluminum current collector on performance of LiNi_(0.5)Co_(0.2)Mn_(0.3)O_2 as cathode material for lithium-ion batteries

用化学蚀刻法制备了微孔铝集流体,通过扫描电镜(SEM)、剥离强度测试、充放电测试和电化学阻抗谱(EIS)测试等方法研究了铝箔表面形貌及其作为正极集流体对锂离子电池正极材料LiNi_(0.5)Co_(0.2)Mn_(0.3)O_2电化学性能的影响。结果表明:蚀刻后铝集流体表面为蜂窝状结构,孔径在5~20 mm,其作为正极集流体制备的样品剥离强度显著提高,0.2 C首次充放电比容量分别为198.70和176.80 mAh/g,首次充放电效率为88.98%。8.0 C循环5次后的放电比容量为134.04m Ah/g,容量保持率仍有75.81%,1.0 C循环50次后放电比容量为161.15 mAh/g,容量保持率为95.62%,倍率和循环性能优良。

Micro-porous Al current collector was prepared by chemical etching method. The morphology, and electrochemical performance of LiNi0.5Co0.2Mn0.3O2 with micro-porous Al current collector were investigated by scanning electron microscope（SEM）, peel strength testing, charge/discharge, and electrochemical impedance spectroscopy（EIS） tests. The results indicate that the etched aluminum has honeycomb structure, the pore size is5-20 mm, the peel strength of sample with micro-porous Al current collector increases obviously, the initial charge/discharge specific capacity of battery are 198.70 and 176.80 mAh/g at 0.2 C, and the first charge and discharge efficiency is 88.98%. Its discharge specific capacity is 134.04 mAh/g after 5 cycles at 8.0 C, capacity retention still retains 75.81%, and the discharge specific capacity is 161.15 mAh/g after 50 cycles at rate of 1.0 C,with capacity retention of 95.62%. The results prove the excellent rate and cycle performance.