Graphene-based nanosheets (GNS) have been studied for use in electrochemical energy storage devices. A deeper understanding about the system is required for achieving enhanced power output and high energy storage. The effects of sulfur doping on the electrochemical properties of GNS are studied for their use as an anode material in lithium-ion batteries. Sulfur doping in GNS contributes to the high specific capacity by providing more lithium storage sites due to Faradaic reactions. In addition, superior rate performance of sulfur-doped GNS (S-GNS) is achieved through the improved electrical conductivity of S-GNS (1743 S m(-1)), which is two orders of magnitude higher than that of GNS (32 S m(-1)). In addition, good cyclic stability of S-GNS is maintained even after 500 cycles at a high current density of 1488 mA g(-1) (4 C). (C) 2014 Elsevier B.V. All rights reserved.