Inhibiting the growth of lithium dendrites at high current densities with oriented graphene foam

Li metal is an ideal anode material for lithium batteries because of its extremely high theoretical specific capacity and the lowest negative electrochemical potential. A main obstruction hindering the utilization of Li metal anodes is the formation of Li dendrites, which lowers the Coulombic efficiency and shortens the lifespan of the battery, and even causes safety problems. In this paper, we report the use of oriented graphene foam (OGF) as a current collector to effectively inhibit the growth of Li dendrites. The Li electrode with the OGF current collector (Li-OGF) showed high coulombic efficiencies of 99%, 97.5% and 93% at 1, 2 and 5 mA cm^-2, respectively. The Li-OGF cell was tested to be stable upon charging/discharging at a practical current density of 1 mA cm^-2 for 300 cycles, indicating that OGF is an excellent skeleton for the electrochemical deposition of Li metal and for inhibiting the growth of Li dendrites.