We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Addressing the Sluggish Kinetics of Sulfur Redox for High‐Energy Mg–S Batteries.
- Authors
Li, Zhenyou; Welle, Alexander; Vincent, Smobin; Wang, Liping; Fuchs, Stefan; Riedel, Sibylle; Roy, Ananyo; Bosubabu, Dasari; García‐Lastra, Juan Maria; Fichtner, Maximilian; Zhao‐Karger, Zhirong
- Abstract
A key challenge for practical magnesium–sulfur (Mg–S) batteries is to overcome the sluggish conversion kinetics of sulfur cathodes, achieving a high energy density and long‐lasting battery life. To address this issue, a doping strategy is demonstrated in a model Ketjenblack sulfur (KBS) cathode by introducing selenium with a high electronic conductivity. This leads to a significantly enhanced charge transfer in the resultant KBS1−xSex cathodes, giving rise to a higher S utilization and less polysulfide dissolution. Compared to the bare S cathode, the S‐Se composite cathodes exhibit a higher capacity, smaller overpotentials, and improved efficiency, serving as better benchmark compounds for high‐performance Mg–S batteries. First principles calculations reveal a charge transport mechanism via electron polaron diffusion in the redox end‐products, that enhances the reaction kinetics. By suppressing polysulfide dissolution in the electrolyte, the use of the KBS1−xSex cathodes also enables a more uniform anode reaction, and thereby significantly extends the cyclability of the cells. To improve the performance, further efforts are made by implementing a Mo6S8 modified separator into the cell. With an optimized cathode composition of KBS0.86Se0.14, the cell applying modified separator shows an improvement of capacity retention by >50% after 200 cycles.
- Subjects
LITHIUM sulfur batteries; SULFUR; ELECTRON diffusion; ENERGY density; OXIDATION-reduction reaction; CHARGE transfer
- Publication
Advanced Energy Materials, 2023, Vol 13, Issue 42, p1
- ISSN
1614-6832
- Publication type
Article
- DOI
10.1002/aenm.202302905