Hongbo Han, Jun Guo, Daijun Zhang
Mar 1, 2011
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Influential Citations
49
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Journal
Electrochemistry Communications
Abstract
Abstract A novel lithium salt, lithium (fluorosulfonyl)(nonafluorobutanesulfonyl)imide (LiFNFSI), is investigated as a conducting salt to improve the high-temperature resilience of lithium-ion cells. It shows better thermal stability than LiPF 6 . The electrolyte having 1.0 M LiFNFSI in a mixture of ethylene carbonate (EC)/ethyl methyl carbonate (EMC) (3:7, v/v) shows high conductivity comparable to LiClO 4 , good electrochemical stability, and does not corrode aluminum. At both room temperature (25 °C) and elevated temperature (60 °C), the graphite/LiCoO 2 cells with LiFNFSI exhibit better cycling performances than those with LiPF 6 . Particularly, at 60 °C, the capacity fading rate of the LiFNFSI-based cell without any additive is 37% after 100 cycles, while the cell with LiPF 6 fails rapidly. These outstanding properties of LiFNFSI make it an attractive candidate to overcome the rapid capacity fading of lithium-ion batteries at elevated temperatures.