Graphene-enveloped sulfur in a one pot reaction: a cathode with good coulombic efficiency and high practical sulfur content.

Graphene-sulfur composites with sulfur fractions as high as 87 wt% are prepared using a simple one-pot, scalable method. The graphene envelops the sulfur particles, providing a conductive shrink-wrap for electron transport. These materials are efficient cathodes for Li-S batteries, yielding 93% coulombic efficiency over 50 cycles with good capacity.