Synthesizing nitrogen-doped porous carbon@sulfur cathode for high-performance and stable cycling Li-S batteries

The rechargeable Lithium-Sulfur battery has been regarded as a promising candidate for the next generation energy storage devices owing to its high energy density, low cost and environment friendliness. The further development of Li-S battery, however, is still hindered by capacity decay and kinetics sluggish caused by the poor electrochemical activity and polysulfide shuttle effect. Herein, a nitrogen-doped porous carbon framework is synthesized by a facial strategy, delivering large special surface area and narrow pore size distribution. As a result, the composited cathode with sulfur loading of 62% shows an excellent rate performance and extreme cycling stability (100 cycles at 1.0 C and 457 mAh g−1 after 500 cycles at 2.0 C), which demonstrates that the N-doped porous carbon host can effectively improve the transport of electron and ion, entrap the dissolved polysulfide, thus improving the electrochemical performance significantly in rate performance and cycle stability.