Influence of pH of Gelatin Solution on Cycle Performance of the Sulfur Cathode

The influence of pH of the gelatin solution on the cycle performance of the sulfur cathode for lithium-sulfur batteries was studied. Scanning electron microscopy measurements revealed that the cathode prepared with pH 10.0 gelatin solution as a binder showed a uniform distribution. The charge/discharge experiments of the lithium-sulfur batteries showed that an initial capacity of 1137 mAh g(-1) and a reversible capacity of 642 mAh g(-1) after 30 cycles were achieved, which were higher than those of the cathodes prepared at pH 5.0 and 8.0. To understand the effect of the pH value of the gelatin solution on the cycle performance of sulfur cathodes, electrochemical impedance spectroscopy and X-ray diffractometry were carried out.