Abstract
High-dielectric solvents were explored for enhancing the sulfur utilization in lithium–sulfur (Li−S) batteries, but their applications have been impeded by low stability at the lithium metal anode. Now a radical-directed, lithium-compatible, and strongly polysulfide-solvating high-dielectric electrolyte based on tetramethylurea is presented. Over 200 hours of cycling was realized in Li|Li symmetric cells, showing good compatibility of the tetramethylurea-based electrolyte with lithium metal. The high solubility of short-chain polysulfides, as well as the presence of active S3 .− radicals, enabled pouch cells to deliver a discharge capacity of 1524 mAh g−1 and an energy density of 324 Wh kg−1. This finding suggests an alternative recipe to ether-based electrolytes for Li−S batteries.
Original language | English |
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Pages (from-to) | 16732-16736 |
Number of pages | 5 |
Journal | Angewandte Chemie - International Edition |
Volume | 57 |
Issue number | 51 |
DOIs | |
Publication status | Published - 17 Dec 2018 |
Keywords
- electrolytes
- high-dielectric systems
- lithium–sulfur batteries
- radicals
- reaction mechanisms