Embedding sulfur into N-doped carbon nanospheres as enhanced cathode for high-performance lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries are considered as one of the most efficient power candidates owing to high energy density about 7-10 times larger than the commercial cathode materials. However, its practical application is impeded by severe "shuttle effect" and low cycle stability. As a consequence, in this work, we report N-doped carbon nanospheres (N-CNSs) composited with S as cathode for Li-S batteries. The stacked carbon nanosphere structure can not only improve the conductivity of cathode, but also work as barriers to retard diffusion of intermediate polysulfide. Owing to the unique structure, the N-CNSs/S cathode exhibits superior electrochemical performances with high specific capacity (1228 mAh g(-1) at 0.1 C), and excellent rate capability as well as good cyclic life. Our smart designed strategy may promote the development of high performance Li-S batteries. (C) 2017 Elsevier Ltd. All rights reserved.