Electrospun LiFePO4/C Composite Fiber Membrane as a Binder-Free, Self-Standing Cathode for Power Lithium-Ion Battery

A LiFePO4/C composite fiber membrane was fabricated by the electrospinning method and subsequent thermal treatment. The thermal decomposition process was analyzed by TG/DSC, the morphology, microstructure and composition were studied using SEM, TEM, XRD, Raman, respectively. The results indicated that the prepared LiFePO4/C composite fibers were composed of nano-sized LiFePO4 crystals and amorphous carbon coatings, which formed a three dimensional (3D) long-range networks, greatly enhanced the electronic conductivity of LiFePO4 electrode up to 3.59x 10(-2) S.cm(-2). The 3D LiFePO4/C fiber membrane could be directly used as a binder-free, self-standing cathode for lithium-ion battery, and exhibited an improved capacity and rate performance. The LiFePO4/C composite electrode delivered a discharge capacity of 116 mAh.g(-1), 109 mAh.g(-1), 103 mAh.g(-1), 91 mAh.g(-1), 80 mAh.g(-1) at 0.1 C, 0.5 C, 1 C, 3 C, 5 C, respectively. And a stable cycling performance was also achieved that the specific capacity could retain 75 mA.g(-1) after 500 cycles at 5 C. Therefore, this LiFePO4/C composite fiber membrane was promising to be used as a cathode for power lithium ion battery.