Hard carbon wrapped in graphene networks as lithium ion battery anode

Abstract

Hard carbon enveloped with graphene networks was fabricated by a facile and scalable method. In the constructed architecture, hard carbon offers large lithium storage and flexible graphene layers can provide a highly conductive matrix for enabling good contact between particles and facilitate the diffusion and transport of electrons and ions. As a consequence, the hybrid anode exhibits enhanced reversible capacity (500 mAh g-1 at current density of 20 mA g-1), rate capability (400 mAh g-1 at 0.2 C, 290 mAh g-1 at 1 C, 250 mAh g-1 at 2 C, and 200 mAh g-1 at 5 C, 1C = 400 mA g-1) and cycle performance. We believe that the outstanding synergetic effect between the graphene networks and the hard carbon structures induces the superior lithium storage performance of the overall electrode by maximally utilizing the electrochemically active graphene and hard carbon particles. As far as we know, the hard carbon/graphene hybrids were firstly fabricated as anode in lithium-ion batteries.