A novel asymmetric hybrid supercapacitor based on Li2FeSiO4 and activated carbon electrodes

A novel, hybrid supercapacitor is fabricated with Li2FeSiO4 (LFSO) as the negative electrode and activated carbon (AC) as the positive electrode in a standard, non-aqueous 1.0 M LiPF6-EC/DMC electrolyte. The electrochemical properties of the LFSO/AC hybrid supercapacitor are investigated by means of cyclic voltammetry (CV), charge/discharge (C/D) measurement and electrochemical impedance spectroscopy (EIS). The CV results reveal the typical capacitance behavior of the LFSO/AC cell within the potential range of 0–3 V. The LFSO/AC cell presents a high discharge capacitance (DSC) of 49 F g−1 at a current density of 1 mA cm−2 and delivers a specific energy of 43 Wh kg−1 and a specific power of 200 W kg−1. The cell exhibits excellent cycleability and greater efficiency over 1000 cycles.