Effect of the Electrolyte Amount and Type on the Lithium‐Sulfur Battery Performance

Lithium‐sulfur (Li‐S) batteries are among the most promising next‐generation battery technologies due to their high theoretical specific capacity. Li‐S battery performance is intricately linked to materials and cell design, with electrolyte design playing a particularly crucial role owing to the complex mechanisms within the cell. Thus, the primary challenge in realizing high‐performance Li‐S batteries lies in achieving reasonable capacities and cycling performance at low electrolyte‐to‐sulfur (E/S) ratios, which might be attainable through unconventional electrolyte systems. This study aims to explore how varying the amount and composition of electrolytes affects the performance of Li‐S batteries across different electrolyte systems. Sulfolane (SL)‐Lithium bis(trifluoromethane)sulfonimide (LiTFSI) and triglyme (G3)‐LiTFSI electrolytes demonstrate superior cycling performance across a range of E/S ratios. Notably, the SL‐LiTFSI electrolyte system shows promise under lean electrolyte conditions, demonstrating superior performance at the lowest E/S ratio of 6 mL g −1 , likely due to sulfolane's electrochemical stability, high dielectric constant, and donor number.