LiFePO ₄ - 3D carbon nanofiber composites as cathode materials for Li-ions batteries

The characterization of carbon nanofiber 3D nonwovens, prepared by electrospinning process, coated with olivine structured lithium iron phosphate is reported. The LiFePO ₄ as cathode material for lithium ion batteries was prepared by a Pechini-assisted reversed polyol process. The coating has been successfully performed on carbon nanofiber 3D nonwovens by soaking in aqueous solution containing lithium, iron salts and phosphates at 70 °C for 2-4 h. After drying-out, the composites were annealed at 600 °C for 5 h under nitrogen. The surface investigation of the prepared composites showed a uniform coating of the carbon nonwoven nanofibers as well as the formation of cauliflower-like crystalline structures which are uniformly distributed all over the surface area of the carbon nanofibers. The electrochemical measurements on the composites showed good performances delivering a discharge specific capacity of 156 mAhg ^-1 at a discharging rate of C/25 and 152 mAhg ^-1 at a discharging rate of C/10 at room temperature.