Carbon materials for Li–S batteries: Functional evolution and performance improvement

Lithium–sulfur (Li–S) battery is one of the most promising candidates for the next generation energy storage solutions, with high energy density and low cost. However, the development and application of this battery have been hindered by the intrinsic lack of suitable electrode materials, both for the cathode and anode. Recently, tremendous progress has been achieved in improving the battery performance by modifying the electrodes by the incorporation of various functional carbon materials. Carbons used in Li–S batteries not only act as conductive additives, but also as shuttling preventers, spatial confiners and anode protectors, etc. In this review, we highlight the evolution of the functionality of carbon materials with the development of Li–S batteries. The scientific understandings of the fundamental design of the materials׳ structure and chemistry in relation to the battery performance are summarized. A way to design next generation Li–S batteries can be drawn through this review.