Merck, 933988, 1,1,2,2-Tetrafluoroethyl 2,2,2-trifluoroethyl ether

General description
1,1,2,2-Tetrafluoroethyl 2,2,2-trifluoroethyl ether (TFTFE) is a fluorinated ether that finds extensive use as an electrolyte solvent and diluent in various battery technologies. TFTFE has a low viscosity, low freezing point (-94 °C lit.), low dielectric constant (~6.7), and high electrochemical stability, making it an ideal candidate for use in lithium-ion batteries, lithium-sulfur batteries, and other battery systems. TFTFE is miscible with many polar organic solvents, including carbonates typically used in battery electrolytes. With a minimum purity level of 99% and free from acid impurities, our TFTFE is a reliable and safe solution for critical battery applications.
Application
Battery-grade 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether (TFTFE) is a versatile co-solvent and additive for various battery systems. In lithium-metal batteries, TFTFE helps to suppress dendrites without raising the interfacial impedance. It also supports the stable cycling of NMC and lithium metal phosphate cathodes by forming a highly fluorinated interphase, which inhibits oxidation and transition metal dissolution. Because of its stability and low viscosity, TFTFE is commonly added in localized high-concentration electrolytes (LHCE) as a diluent and flame-retardant. In lithium-sulfur batteries, TFTFE plays a key role as both a polysulfide-restraining solvent and a film-forming agent, addressing the polysulfide shuttle (PSS) effect and improving battery performance. Additionally, TFTFE plays a critical role in cell systems with solvate ionic liquids (SIL) as an ionic conduction-enhancing ingredient, particularly for high-rate cycle environments. Our high-purity, anhydrous TFTFE is an ideal battery-grade additive for advanced battery technology.