静电纺丝合成LiFe_(0.5)Mn_(0.4)Co_(0.1)PO_(4)纳米纤维及性能研究

Study on the properties and synthesis of LiFe_(0.5)Mn_(0.4)Co_(0.1)PO_(4) nanofibers by electrospinning

通过静电纺丝技术合成了LiFe_(0.5)Mn_(0.4)Co_(0.1)PO_(4)纳米纤维并且作为锂离子电池正极材料.利用扫描电镜和X射线衍射仪对材料的形貌和晶体纯正度进行分析,并采用首圈循环充电、放电、倍率、循环伏安和交流阻抗来检测静电纺丝纳米纤维正极材料的电池性能.结果表明,静电纺丝制备的电池正极材料具有良好的纳米级纤维形貌,结晶度纯正等特点;在0.1 C倍率下首次充、放电比容量分别为140.1 mA·h/g、121.4 mA·h/g, 0.1 C倍率下循环50圈,库伦效率维持在了98.9%;在不同倍率测试时(0.1 C、0.5 C、1 C),体现出良好的稳定性(容量保持率96.17%、96.1%、95.0%),体现出较高的电池容量以及循环稳定性.

The LiFe_(0.5)Mn_(0.4)Co_(0.1)PO_(4) nanofibers were synthesized by electrospinning technology and used as cathode materials for lithium ion batteries.The morphology and crystal purity of the materials were analyzed by scanning electron microscopy and X-ray diffraction, respectively.The battery performance of electrospinning nanofiber cathode materials were tested by first cycle charging and discharging, rate, cyclic voltammetry and AC impedance.The results showed that the cathode materials prepared by electrospinning have good nano-fiber morphology and pure crystallinity.The first charge and discharge specific capacities at 0.1 C rate are 140.1 mA·h/g and 121.4 mA·h/g, respectively.The Coulomb efficiency was maintained at 98.9 % after 50 cycles at 0.1 C.At different rates(0.1 C,0.5 C,1 C),it shows good stability(capacity retention rate of 96.17 %,96.1 %,95.0 %),high battery capacity and cycle stability.