The electrochemical properties of high-capacity sulfur/reduced graphene oxide with different electrolyte systems

The lithium/sulfur battery is a promising electrochemical system with high capacity, which is well-known to undergo a complex multistep reaction during the discharge process. Two types of electrolytes including poly(ethylene glycol) dimethyl ether (PEGDME)-based and 1,3-dioxolane (DOL)/dimethoxyethane (DME)-based electrolytes were investigated here. Furthermore, LiNO3 additive was introduced into the electrolyte in order to effectively eliminate the overcharge effect. The lithium sulfur battery with 1.0 M LiN(CF3SO2)2 in PEGDME with 0.1 M LiNO3 shows highly stable reversible capacity of 624.8 mAh g−1 after 200 cycles and improved average coulombic efficiency of 98%.

► Two types of electrolytes were investigated here.
► LiNO3 additive was introduced into the electrolyte to eliminate the overcharge effect.
► Highly stable reversible capacity of 624.8 mAh g−1 after 200 cycles can be obtained.
► Average coulombic efficiency of 98% can be achieved.