Preparation and characterization of sulfur–polypyrrole composites with controlled morphology as high capacity cathode for lithium batteries

Sulfur was highly combined with two types of polypyrrole (PPy) in granular (G-PPy) and tubular(T-PPy) morphology by in-situ oxidation and co-heating methods. The morphology of polypyrrole shows a significant effect on the dispersion status and electrochemical behaviors of the sulfur. A stable capacity close to 500 mAh/g was maintained over 60 cycles for the S/T-PPy composite. Electrochemical measurement results suggest that the S/T-PPy composite is obviously superior to the S/G-PPy composite. It is suggested that the as-proposed tubular PPy could be a promising electric matrix for sulfur active host for a high energy density lithium–sulfur battery.