摘要
以简单的球磨-干燥-煅烧法,制备了具有稳定α-NaFeO2型层状结构(R-3m空间群)的LiNi0.5Co0.2Mn0.3O2型的三元正极材料。通过X射线衍射分析、傅里叶红外光谱、扫描电子显微镜、充放电循环、循环伏安、交流阻抗谱等手段测试了样品的理化性能。研究表明:球磨浆料的陈化温度对样品性能有明显的影响。在0.1C、1C、2C、3C、5C、6C、8C和10C倍率电流和连续充放电下,经过50℃陈化浆料制备的亚微米样品的放电容量分别为172.3、161.4、151.5、145.2、136.9、133.2、126.3、121.4 mA·h/g,表现出较好的大倍率电流放电性能。随着循环次数的增加,该样品的锂离子扩散系数和电荷传递阻抗均发生变化。该样品的未循环、充放电循环1次及循环40次样品的锂离子扩散速率分别为1.45×10^-16、6.60×10^-16、7.92×10^-15 cm/s。
LiNi0.5Co0.2Mn0.3O2 cathode materials with a stable layered structure(α-NaFeO2,R-3m space group)prepared by using a simple ball milling-drying-calcination method.The physico-chemical performance of the as-prepared cathode materi-als was characterized by means of X-ray diffraction analysis,Fourier transform infrared spectroscopy,scanning electron microscopy,charge-discharge cycle,cyclic voltammetry and electrochemical spectroscopy etc..The results showed that the aging temperature of the precursor obviously affected the electrochemical performance.Under the contitions of 0.1C,1C,2C,3C,5C,6C,8C and 10C rate currents and continuous charge and discharge,the sample prepared using the aging slurry at 50℃havd a discharge capacities of 172.3,161.4,151.5,145.2,136.9,133.2,126.3 and 121.4 mA·h/g,respectively,and showed a good large-rate current discharge performance.As the number of cycles increases,both the Li+diffusion coefficient and the charge transfer impedance of the sample were changed.The Li+diffusion rates of the sample which under the conditions of no cycle,1 cycle and 40 cycles were 1.45×10^-16,6.60×10^-16 and 7.92×10^-15 cm/s,respectively.
作者
余欣瑞
高峰
吕超
生瑜
童庆松
Yu Xinrui;Gao Feng;LU Chao;Sheng Yu;Tong Qingsong(College of Chemistry and Materials,Research Center of Lithium Battery,Fujian Nomal University,Fuzhou 350007,China)
出处
《无机盐工业》
CAS
CSCD
北大核心
2019年第10期51-55,共5页
Inorganic Chemicals Industry
基金
福建省科技厅高校产学合作项目（2016H6006）
福州市科技局资助项目（2017-G-68）
