Abstract:

Currently lithium sulfur (Li-S) batteries are recognized as the most promising novel secondary battery candidates due to their high energy density, abundant sulfur and environment benign. The functional electrolyte is a major component of Li-S batteries, which physical property characteristics are closely related to the electrochemical performance of Li-S batteries. Nevertheless, its development is restricted by some key technologies. The polysulfides dissolve into electrolytes and cause the consequent shuttle phenomenon, resulting in low coulombic efficiency, fast capacity fade and serious self-discharge of Li-S batteries. This paper reviews the recent research progress for these problems of the electrolytes for Li-S batteries. ① the modification and optimization of the solvent components, lithium salts and additives of the organic liquid electrolytes to improve the performance of Li-S batteries, ② the effect on polysulfides dissolution by ionic liquid electrolytes, and ③ the suppression of the shuttle effects by (semi-) solid-state electrolytes. Finally, the future research trends of the functional electrolytes for Li-S electrolytes are proposed.