Cabbage-like nitrogen-doped graphene/sulfur composite for lithium-sulfur batteries with enhanced rate performance

The cabbage-like nitrogen-doped graphene/sulfur composite (NG/S) was prepared in this work. This novel cabbage-like morphology has a three-dimensional connected structure with unique tiny ravines and thin folds, which can offset the defect of nonconductive sulfur species and store sulfur. Based on the new structure, the sulfur loading of NG/S is up to 74 wt% by thermogravimetric analysis. Electrochemistry tests indicate that the NG/S cathode delivers a discharge specific capacity of 1309 mAh g−1 at 1 C (1 C = 1672 mA g−1), and the stable reversible capacity can be maintained at approximately 663 mAh g−1 after 300 cycles at 1 C, together with the capacity decay of per cycle is only 0.02%.