Abstract
Li-S batteries have been extensively studied using rigid carbon as the host for sulfur encapsulation, but improving the properties with a reduced electrolyte amount remains a significant challenge. This is critical for achieving high energy density. Here, we developed a soft PEO10LiTFSI polymer swellable gel as a nanoscale reservoir to trap the polysulfides under lean electrolyte conditions. The PEO10LiTFSI gel immobilizes the electrolyte and confines polysulfides within the ion conducting phase. The Li-S cell with a much lower electrolyte to sulfur ratio (E/S) of 4 gE/gS (3.3 mLE/gS) could deliver a capacity of 1200 mA h/g, 4.6 mA h/cm2, and good cycle life. The accumulation of polysulfide reduction products, such as Li2S, on the cathode, is identified as the potential mechanism for capacity fading under lean electrolyte conditions.
Original language | English (US) |
---|---|
Pages (from-to) | 3061-3067 |
Number of pages | 7 |
Journal | Nano letters |
Volume | 17 |
Issue number | 5 |
DOIs | |
State | Published - May 10 2017 |
All Science Journal Classification (ASJC) codes
- Bioengineering
- General Chemistry
- General Materials Science
- Condensed Matter Physics
- Mechanical Engineering