Enhanced cycle performance of hollow polyaniline sphere/sulfur composite in comparison with pure sulfur for lithium–sulfur batteries

Sulfur deposited on a hollow polyaniline sphere was prepared through in situ synthesis and used to investigate the electrochemical properties of lithium/sulfur cells. The fabricated hPANIs@S composite presented an excellent reversible capacity of 601.9 mAh g−1 after 100 cycles at 170 mA g−1. The capacity increased with the cycle increase, especially at high charge/discharge current. For example, the capacity had only approximate 270 mAh g−1 after initial 121th cycle at 510 mA g−1, and the capacity steadily increased to 380 mAh g−1 after 180th cycle at similar current. These results indicated that cycle property improved compared with that of pure sulfur prepared through in situ synthesis under similar conditions. The enhanced cycle property of the hPANIs@S composite could be due to the homogeneous distribution of fine sulfur particles on the PANI surface, which stabilized the nanostructure of sulfur and enhanced its conductivity during charge/discharge cycles.