Preparation and electrochemical performances of LiFePO₄/C composite nanobelts via facile electrospinning

LiFePO₄/C composite nanobelts were synthesized by calcination of the [LiOH + Fe(NO₃)₃ + H₃PO₄]/polyvinyl pyrrolidone (PVP) electrospun nanobelts. PVP was used as the electrospinning template and carbon source. During the calcination, [LiOH + Fe(NO₃)₃ + H₃PO₄] were transformed to lithium iron phosphate (LiFePO₄) and PVP was decomposed into carbon. The morphology and properties of the as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller (BET) specific surface area analysis, electrochemical impedance spectroscopy and galvanostatic charge–discharge measurements. The results indicate that the mean width of LiFePO₄/C composite nanobelts is 2.50 ± 0.33 μm, the average thickness is about 162 nm and the BET specific surface area is 19.4 m² g⁻¹. The addition of carbon does not affect the structure of LiFePO₄, but improves its electrochemical performances. At the current density of 0.2 C, the initial discharge capacity of LiFePO₄/C electrode is 123.38 mAh g⁻¹ and there is no obvious capacity fading after 50 cycles. The formation mechanism of LiFePO₄/C composite nanobelts was also proposed.