不同充放电电压对Li_(1.133)Ni_(0.3)Mn_(0.567)O_2结构的分析

Structure analysis of Li_(1.133)Ni_(0.3)Mn_(0.567)O_2 under different charge-discharge voltages

通过共沉淀法合成前驱体和高温固相反应,实现Ni、Mn的固溶合成Li_(1.133)Ni_(0.3)Mn_(0.567)O_2富锂锰基正极材料,分别在不同的电压下进行50次充放电循环,然后采用X射线衍射光谱法(XRD)表征在不同电压充放电循环后的正极材料,并对其进行结构精修。研究发现,随着充放电电压的升高,充放电比容量提高,但循环性能迅速下降。另外,XRD测试也表明,充放电电压递升,相应的正极材料的(003)峰的位置逐渐向小角度偏移,此外4.6 V电压充放电后的正极材料的结构变化最大。

Li1.133Ni0.3Mn0.567O2 cathode materials were synthesized by co-precipitation method and solid phase reaction at high temperature. The cathode materials were carried on 50 cycles at different voltages respectively, and XRD technique was used for structure refinement analysis of the cathode material after discharge. It＇ s found that as the discharge voltage increases, the capacity increases, but the cycling performance rapidly declines. XRD tests show that the charge-discharge voltage steps up, and （003） peak position gradually shifts to a small angle. The structure change of the cathode material reaches the maximum after charged and discharged at 4.6 V.