燃烧辅助合成LiNi0.05Mn1.95O4粉体及其性质研究

以醋酸锂、醋酸锰、硝酸镍、柠檬酸、乙二醇为原料,采用燃烧辅助合成锂离子电池正极材料LiNi0.05Mn1.95O4。采用X射线衍射、扫描电子显微镜、循环伏安、恒电流充放电等技术对合成产物进行物相、形貌及电化学性能分析与测试。结果表明:采用燃烧辅助合成LiNi0.05Mn1.95O4过程中,前驱体在空气中点燃后已形成单一尖晶石相,经750℃热处理4 h后得到的LiNi0.05Mn1.95O4粉末X射线衍射峰尖锐,结晶性好,晶粒尺寸均匀。该法合成的LiNi0.05Mn1.95O4粉末首次放电比容量为117.5 mAh.g-1,经50次充放电循环后的容量保持率为95.1%,合成的LiNi0.05Mn1.95O4粉末具有良好的电化学性能。

Combustion-assisted Synthesis and Characterization of LiNi0.05Mn1.95O4 Powders

LiNi0.05Mn1.95O4 powders were prepared by combustion assisted sol-gel method using lithium acetate,manganese acetate,nickel nitrate,citric acid and ethylene glycol as starting materials.The structure,morphology,and electrochemical properties of the powders were investigated by X-ray diffraction,scanning electron microscopy,cyclic voltammetry and galvanostatic charge-discharge experiments.The results show that LiNi0.05Mn1.95O4 precursor gel ignited in air for several minutes has already been the structure of spinel.The powders heated at 750℃ for 4hours prepared by this technique is well crystallized.The grains are small and uniform.The specific capacity of the prepared powders is 117.5 mAh· g-1 and show the capacity retention of 95.1% after being cycled 50 times.