5V LiNi_(0.5)Mn_(1.5)O_4正极材料掺杂改性研究

Research on doping of 5V LiNi_(0.5)Mn_(1.5)O_4-based positive electrode

用溶胶-凝胶法结合高温后退火处理合成了掺杂Cr的LiNi0.5-0.5yCryMn1.5-0.5yO4(y=0.05,0.10,0.15,0.00),通过X射线衍射(XRD)、恒流充放电测试表征了材料的结构、电化学性能。结果表明,在电压范围为3.5～5.0 V内,LiNi0.45Cr0.1Mn1.45O4电化学性能最好,首次放电容量可达136.2mAh/g,0.1 C循环20次后,容量保持率99.7%;1 C倍率循环50次后,容量仍然有116.2 mAh/g,基本不衰减,大倍率循环有良好的容量和循环性能。

LiNi0.5-0.5yCryMn1.5-0.5yO4 was prepared by sol-gel method combined with annealing treatment after high temperature.XRD and charge-discharge text were applied to examine the structure,electrochemical performance.The results indicated that LiNi0.45Cr0.1Mn1.45O4 had the best electrochemical performance with the first discharge capacity of 136.2 mAh/g in 3.5~5.0 V,and the capacity retention was 99.7% after 20 cycles at 0.1 C.It was still 116.2 mAh/g after 50 cycles at 1 C,which meant excellent capacity and cycle performance.