In this work, different fluorinated cyclic carbonates including FEC, DFEC, TFPC, HFEEC and NFPEC were used in an attempt to form superior solid electrolyte interphases (SEI).Cyclic fluorinated carbonates with various chemical structures were designed, synthesized and characterized by different analytical methods including NMR, GC-MS and FT-IR. Electrolytes were prepared by dissolving 1.0 M LiPF6 in a mixture of fluorinated cyclic carbonate and FEMC in a volume ratio of 3 to 7. The performance of full cells (graphite/LiNi0.5Mn0.3Co0.2O2) using an electrolyte composition containing FEC and TFPC showed the best capacity retention. With the addition of 1 wt.% additive (DTD), the cell performance of the TFPC based electrolyte can be further improved as indicated from the exceptional capacity retention of the TFPC cell at high temperature (55 oC). In conclusion, various fluorinated cyclic carbonates were synthesized and among all the carbonates, TFPC based electrolyte displayed promising properties for their application in high voltage lithium-ion batteries.
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