Elongated graphitic hollow nanofibers from vegetable oil as prospective insertion host for constructing advanced high energy Li-Ion capacitor and battery

We report the facile and low temperature synthesis of one dimensional graphitic fibers with hollow structured morphology (VO-CF) by modified chemical vapor deposition using vegetable oil as a carbon source. Graphitization of the prepared phase is validated with various analytical tools. Prior to the fabrication of charge storage devices like Li-ion battery (LIB) and Li-ion capacitor (LIC), Li-insertion properties of VO-CF is studied in half-cell assembly. Mass adjustment between the electrodes are very crucial and adjusted for aforesaid energy storage devices. Pre-treatment or pre-lithiation is carried out using an electrochemical approach in Swagelok fittings with Li. LIB assembly with LiFePO₄ delivered a maximum energy density of ∼233 Wh kg⁻¹ whereas the LIC displayed the energy density of ∼112 Wh kg⁻¹ when paired with activated carbon electrode. Both LIB and LIC assemblies rendered very decent cycling profiles for extended 500 and 10000 cycles, respectively.