Heteroatoms-Doped Porous Carbon Derived from Tuna Bone for High Performance Li-S Batteries

Abstract

Nowadays, the practical application of Li-S batteries is still inhibited by its inferior cycle stability caused by the shuttle effect. Herein, we report the design and fabricate of a fishbone based porous carbon (FBPC) for ultralong cycle life Li-S batteries. Prepared by carbonizing the tuna bone with activation process, FBPC is a heteroatoms-doped hierarchical porous carbon material which owns following merits: i) micropores of FBPC confine the dissolved polysulfides and offer adequate electrochemical reaction interface; ii) mesopores of FBPC not only facilitate infiltration of the electrolyte but also accommodates the volume expansion/contraction during the discharge/charge process; iii) the doped N/S/O heteroatoms increase the reactive sites, present strong polysulfides binding and improve the electroconductivity of carbon matrix. Li-S batteries with FBPC separator exhibit excellent cycling stability (0.064% capacity fading per cycle at 1C) and deliver a high discharge capacity of 1397.5mAhg−1 at 0.2C. Even after 700 cycles the capacity still retain as high as 599.9mAhg−1 at 1C. These superior performances as well as abundant precursor and facile preparation process represent the promising prospect of the designed FBPC being applied to the high-performance Li-S batteries.