Sulfur Encapsulated Porous Rattle-Type Carbon Sphere as Cathode Material for Lithium Sulfur Batteries

Abstract

A porous rattle-type carbon sphere (PRC) was synthesized by a facile one-pot synthesis method from resorcinol-formaldehyde precursor as the carbon source. Field emission scanning electron microscopy and transmission electron microscopy showed that the carbon sphere has a unique rattle-type structure with meso-sized pores. The sulfur/carbon composite was prepared by encapsulating sulfur into the PRC by the melt diffusion method. The lithium sulfur battery assembled with the S/PRC composite as the cathode delivered a high initial capacity of 1122 mAh/g and good capacity retention of 656 mAh/g at 0.1 C-rate after 100 cycles. The composite also showed significantly high reversible capacities at high C-rates, demonstrating the advantage of the synthesized sulfur/carbon composite as cathode material for lithium sulfur batteries.