论文部分内容阅读
采用MnCO3或MnO2为锰源,设计了两条工艺路线,并分析了这两种工艺对富锂正极材料Li1.2Mn0.54Ni0.13Co0.13O2结构、形貌、振实密度及电化学性能的影响。研究结果表明,两种工艺制备的材料都具有层状结构,二次颗粒都呈球形,球形颗粒的直径都在2~15μm,一次颗粒0.2~1.0μm;但是在两种不同的工艺下,球形颗粒的聚集程度不一,其中以MnO2为锰源,制备的材料的颗粒接触最为紧密,而且其振实密度高,为1.5g·cm-3。以制备出的材料作为电池的正极材料,组装2032扣式电池,在0.1C(20mA·g-1),电压范围2.0~4.8V,测试材料的首次充放电,其中以MnCO3为锰源,制备的材料的首次放电比容量为最高,为262.1mAh·g-1,首次库伦效率为76.8%。在不同倍率(0.2C,0.5C,1.0C和3.0C)下测试电池性能,以MnO2为锰源,3.0C下的放电比容量为183.5mAh·g-1。因此,采用MnO2为锰源制备出的富锂正极材料具有较高的倍率性能。
Using MnCO3 or MnO2 as the manganese source, two process routes were designed and the effects of these two processes on the structure, morphology, tap density and electrochemical performance of the Li1.2Mn0.54Ni0.13Co0.13O2 cathode material were analyzed . The results show that the materials prepared by the two processes all have a layered structure, the secondary particles are spherical, the diameter of the spherical particles is in the range of 2-15 μm and the primary particles are 0.2-1.0 μm; however, under two different processes, the spherical The aggregation degree of the particles is different, among them, MnO2 is the source of MnO2, the particles of the prepared material have the most contact with each other, and the tap density is 1.5 g · cm-3. The prepared material was used as the positive electrode material of the battery. A 2032 button cell was assembled and tested for initial charge and discharge at 0.1 C (20 mA · g -1) and a voltage range of 2.0-4.8 V, in which MnCO3 was used as a manganese source to prepare Of the material for the first discharge capacity for the highest, 262.1mAh · g-1, the first coulombic efficiency was 76.8%. The cell performance was tested at different magnifications (0.2C, 0.5C, 1.0C and 3.0C). MnO2 was used as a manganese source and the discharge capacity at 3.0 C was 183.5 mAh · g-1. Therefore, the use of MnO2 as manganese source prepared lithium-rich cathode material with high rate performance.