High energy and power lithium-ion capacitors based on Mn3O4/3D-graphene as anode and activated polyaniline-derived carbon nanorods as cathode

Abstract

Recently, high performance energy storage devices are increasingly required in many new fields such as smartphone, pilotless automobile. Lithium-ion capacitors (LICs) have become the promising energy storage devices because of the higher power density, electrostatic capacity and long cycle life. Nevertheless, the limitation of the battery-type anode electrode and the capacitance-type cathode electrode with slow kinetics and low specific surface area leads to the LICs remaining lower energy density in high current density. In this report, a high performance LIC assembled by Mn3O4-graphene coupled with activated polyaniline-derived carbon (APDC) is firstly presented. Mn3O4-G composite material exhibits an outstanding invertible capacity of 489.8 mAh g−1 (at 1 A g−1) in a wide working window (0.01–3 V vs. Li/Li+) with an excellent coulombic efficiency in half cell, which is the highest capacitance reported for Mn3O4 so far. By utilization of Mn3O4-G composite as anode and APDC with the large surface of 1641.9 m2 g−1 as cathode, the assembled LIC of Mn3O4-G//APDC possesses an energy density of 97.2 Wh kg−1 at power density of 62.5 W kg−1, even at a relatively higher power density of 6250 W kg−1, its energy density can retain 5.0 Wh kg−1.