Abstract
The advancement of the lithium-sulfur (Li-S) batteries is immensely impeded by two main challenges: polysulfide shuttling between the electrodes and Li dendrite formation associated with the Li-metal anode. To tackle these challenges, we synthesized a polydopamine coated bacterial cellulose (PDA@BC) separator in a way to create physical and chemical traps for the shuttling polysulfides and to control the Li+ flux. While nanocellulose offers its dense network as a physical trap, the presence of polydopamine in the separator offers polar functional groups which not only has a high binding energy towards the polysulfides but also helps in redistribution of the Li+ ions across it. The electrochemical and physiochemical results suggest that the synthesized separator can have practical applicability owing to its superior performance compared to a commercial separator. The Li-S batteries assembled with this separator showed a specific discharge capacity of 1449 mAh/g at 0.1C and 877 mAh/g at 1C, and a capacity fade of 0.03 % per cycle over 650 cycles at 1C. Using a PDA@BC separator, a practical Li-S battery cell with S loading of 7.5 mg cm−2 (and E/S ratio of 10 µLmg−1, 82 % S ratio) was also tested at 1C, which delivered a capacity of ∼ 6 mAh cm−2 for 500 cycles.
Original language | English (US) |
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Pages (from-to) | 556-565 |
Number of pages | 10 |
Journal | Journal of Colloid And Interface Science |
Volume | 656 |
DOIs | |
State | Published - Feb 15 2024 |
Keywords
- Bacterial cellulose
- Battery separator
- Li-metal battery
- Lithium sulfur battery
- Polydopamine
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry