Ethyl 1,1,2,2-tetrafluoroethyl ether (ETFE) is a fluorinated linear ether with several fundamental properties that make it useful in batteries. First, ETFE is miscible with many polar organic solvents used in electrolyte formulations, which improves the ionic conductivity of the battery. Additionally, ETFE has a relatively low viscosity (486 mPas at 23 °C) and a low boiling point (58 °C), which make it a versatile diluent for low-temperature applications.
Ethyl 1,1,2,2-tetrafluoroethyl ether (ETFE) is a highly effective additive in lithium-ion and sodium-ion batteries for improving battery performance, increasing safety, and reducing flammability. ETFE is a versatile co-solvent with high miscibility, which allows it to be blended with other solvents to achieve high ionic conductivities. It is also a good SEI-forming electrolyte additive, stabilizing the Na electrode surface and enhancing the stability of high-voltage batteries. ETFE is particularly useful as an electrolyte co-solvent in lithium-sulfur (Li-S) batteries. Studies have shown that ETFE-containing electrolytes improve the stability of the electrolyte/anode interface and enhance the cycling, rate, and self-discharging of the Li-S cell more than glyme-based cosolvents or unblended solvents.
