| Affiliation: | 1. Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Chemical Science and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL, 60439 USA;2. Chemical Science and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL, 60439 USA;3. Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong |
| Abstract: | Electrolyte modulation simultaneously suppresses polysulfide the shuttle effect and lithium dendrite formation of lithium–sulfur (Li-S) batteries. However, the sluggish S redox kinetics, especially under high S loading and lean electrolyte operation, has been ignored, which dramatically limits the cycle life and energy density of practical Li-S pouch cells. Herein, we demonstrate that a rational combination of selenium doping, core–shell hollow host structure, and fluorinated ether electrolytes enables ultrastable Li stripping/plating and essentially no polysulfide shuttle as well as fast redox kinetics. Thus, high areal capacity (>4 mAh cm−2) with excellent cycle stability and Coulombic efficiency were both demonstrated in Li metal anode and thick S cathode (4.5 mg cm−2) with a low electrolyte/sulfur ratio (10 μL mg−1). This research further demonstrates a durable Li-Se/S pouch cell with high specific capacity, validating the potential practical applications. |
