Correlation between positive-electrode morphology and sulfur utilization in lithium–sulfur battery

Lithium–sulfur batteries using positive electrodes (cathodes) with various binders are assembled to examine the correlation between cathode morphology and battery performance. The pore distribution and pore area of the cathodes are measured and to understand the effect on sulfur utilization on the discharge rate. The matrix of binders consists of polytetrafluoroethylene (PTFE)+carboxymethyl cellulose (CMC), PTFE+polyvinyl alcohol (PVA), and polyvinylpyrrolidone (PVP). The cathode with PTFE+CMC (18:2 wt.%) as binder shows the greatest enhancement of capacity. The specific surface area of the composite material and the sulfur utilization in this cathode are about 10 m2 g−1 and more than 65%, respectively.