Tailoring the Electrode Interface with Enhanced Electron Transfer for High-Rate Lithium-Ion Battery Anodes

Contact interface between the active materials and the current collector is essential for electron transfer rate and the mechanical properties of an electrode. In this study, various types of contacts between the active material (graphene sheets) and the metal current collector are created through different fabrication methods, and their impacts to the electrochemical performance are investigated. Intimate “sheet contact” is observed between graphene sheets and Ni foam after KOH in situ activation, which is believed to facilitate the electron transfer. The anode that is tailored to have “sheet contact” delivers a reversible capacity of 1457 mAh g–1 at 0.1 C, which is higher than the electrode obtained by a commercial drop-casting method and comparable to most of the high-end graphene-based anodes. In addition, the anode delivers a high capacity of 173 mAh g–1 with a short charging time of 56 s, indicating its promising use as a high-rate LIB anode.