CNT-intercalated rGO/sulfur laminated structure for high-rate and long-life lithium-sulfur batteries

摘要

Lithium-sulfur (Li-S) batteries represent one of the next-generation Li-ion batteries. However, the poor conductivity and large volumetric expansion of sulfur result in low rate performance and unfavorable cycle stability. Herein, a laminated structure of sulfur/reduced graphene oxide intercalated by carbon nanotube (CNT-rGO/S) composites was designed and fabricated for the first time to address the issue. The composites prepared via hydrothermal coprecipitation was endowed a perfect crystal and highly integrated structure, which retained a good electrical conductivity and accommodated the sulfur volume expansion due to the sufficient free space between the CNT-intercalated graphene layers. The CNT-rGO/S cathode exhibits a good capacity of 783.3 mAh g(-1) at 0.5 C and a desirable cycling stability with 77.2% of the capacity remaining after 1000 cycles even at a rate as high as 5 C, which offers great potential for practical applications in Li-S batteries. (C) 2018 Elsevier B.V. All rights reserved.