Fig. 6: Li-ion battery performance: performance of graphene flakes/SWCNT (85:15 wt%) as lithium-ion battery anodes.

a Cyclic voltammograms at a scan rate of 0.1 mV s−1 for various cycles. b Cycling capacity versus cycle number for composite anodes based on graphene flakes cycled initially at 30 mA g−1 and then at 100 mA g−1. Coulombic efficiency (CE) is shown in the inset. c Galvanostatic charge-discharge curves measured at different charging currents. d Specific capacity as a function of charging current. In all cases, CSp is normalised to the graphene mass.