In situ formation of protective coatings on sulfur cathodes in lithium batteries with lifsi-based organic electrolytes
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Development of sulfur cathodes with 100% coulombic efficiency (CE) and good cycle stability remains challenging due to the polysulfide dissolution in electrolytes. Here, it is demonstrated that electrochemical reduction of lithium bis(fluorosulfonyl)imide (LiFSI) based electrolytes at a potential close to the sulfur cathode operation forms in situ protective coating on both cathode and anode surfaces. Quantum chemistry studies suggest the coating formation is initiated by the FSI(-F) anion radicals generated during electrolyte reduction. Such a reduction additionally results in the formation of LiF. Accelerated cycle stability tests at 60 °C in a very simple electrolyte (LiFSI in dimethoxyethane with no additives) show an average CE approaching 100.0% over 1000 cycles with a capacity decay less than 0.013% per cycle after stabilization. Such a remarkable performance suggests a great promise of both an in situ formation of protective solid electrolyte coatings to avoid unwanted side reactions and the use of a LiFSI salt for this purpose.
Details
Original language | English |
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Article number | 1401792 |
Journal | Advanced energy materials |
Volume | 5 |
Issue number | 6 |
Publication status | Published - 1 Mar 2015 |
Peer-reviewed | Yes |
Keywords
Sustainable Development Goals
ASJC Scopus subject areas
Keywords
- batteries, dissolution, cathodes, electrolytes, protective coatings