Anthracite-derived carbon-based electrode materials for high performance lithium ion capacitors

Abstract

The capacity and electrochemical kinetics mismatches between cathode and anode are two major obstacles for lithium ion capacitors. In the work, graphene coating and electrochemical prelithiation are used to reinforce the properties of activated carbon and graphitized carbon as cathode and anode. The activated carbon with high specific surface area, and the graphitized carbon with porosity are prepared with anthracite as raw material, then both of them are modified with anthracite-derived graphene. As cathode, activated carbon coated with graphene shows a capacitance of 302 F g−1 with 75% capacitance retention after 10,000 cycles. The anode, graphitized carbon coated with graphene sheets delivers a capacity of 568.1 mAh g−1 at 0.1 A g−1 with 97% capacitance retention after 300 cycles. The LICs assembled with cathode and prelithiated anode show high energy and power densities, 315.1 Wh kg−1 at 300 W kg−1 and 133.3 Wh kg−1 at 15000 W kg−1, and superior cyclic stability, 78% capacity retention after 10,000 cycles. This work illustrates surface graphene coating and prelithiation to balance the capacity and electrochemical kinetics mismatches of electrodes in LICs and blaze an efficient route to convert anthracite to high performance electrodes for LICs and other energy storage systems.