KCS

Sulfur has a high specific capacity of 1672 mAh/g as one of the promising lithium secondary battery cathode materials than traditional metal oxides/phosphates cathodes. However, it has been faced with the rapid capacity fading due to the dissolution of polysulfides and the precipitation of lithium polysulfides. To make up for the weak points in lithium sulfur batteries, many researchers have studied various methods of overcoming these problems, controlling of carbon coating and electrolyte. In this study, the graphene oxide-coated polymer sulfur composites have an important role in accommodating volume expansion of the coated sulfur particles during discharge, trapping soluble polysulfide intermediates, and rendering the sulfur particles electrically conducting. The resulting these materials showed high specific capacity and good cycle ability up to ~ 700 mAh/g over more than 100 cycles. Moreover, the introduction of LiNO3 additive seems to have improved the coulombic efficiency over 95% at 0.2 C.