Ultrasound assisted design of sulfur/carbon cathodes with partially fluorinated ether electrolytes for highly efficient Li/S batteries.

A one-step, eco-friendly ultrasound-assisted process is established for the rapid synthesis of sulfur-carbon composite cathode materials, avoiding the widely used, energy inefficient "melt-down" process for Li-S batteries. It is demonstrated that, without inserting sulfur into pores of carbon, the coulombic efficiency of SC/Li cell in the new DOL/D2 electrolyte is greater than 96% for 100 cycles, which is far superior to the reported numerous electrolyte formulations.