Recent advances in graphene materials used in Li-S batteries

The lithium-sulfur battery is considered one of the most promising next-generation secondary batteries owing to its high theoretical specific capacity (1 675 mAh/g) and high energy density (2 600 Wh/kg). Graphene has excellent electrical conductivity, a high surface area and open space as well as an excellent electrochemical performance, and is considered the ideal platform for loading low-conductivity sulfur and lithium sulfide for the use as the cathodes of lithium-sulfur batteries. This article summarizes recent developments on graphene and graphene-based materials for lithium-sulfur batteries, including nanocomposites of sulfur with ( reduced) graphene oxide, heteroatom-doped graphene, three-dimensional graphene foams and graphene-porous carbon. The impact of these graphene-based nanocomposites with various compositions and microstructures on improvements in the performance and mechanism of lithium-sulfur batteries are discussed. Prospects for lithium-sulfur battery development are outlined.