F2DEE {1,2-Bis(2-fluoroethoxy)ethane, >99.0%} as Battery Electrolyte Co-Solvent and Additive, 10-50 g/bottle, CBESAF2DEE

F2DEE (1,2-bis(2-fluoroethoxy)ethane or a structurally analogous fluorinated diethylene glycol diether) is a lightly fluorinated linear ether engineered as an advanced co-solvent, solvation-sheath modifier, and interphase-directing additive for next-generation lithium-metal and lithium-sulfur batteries. By introducing a single fluorine atom onto each terminal ethyl group of a diethylene glycol backbone, F2DEE provides high solvating capability while moderately enhancing electrochemical and interfacial stability compared to conventional unfluorinated glymes.

The main functional roles of the F2DEE are: (1) Solvation Sheath & Fast Ion Transport: F2DEE coordinates smoothly with lithium ions (Li+), facilitating rapid desolvation kinetics and high ionic mobility across broad thermal ranges, which benefits low-temperature and high-rate performance. (2) Controlled Interphase (SEI) Passivation: Due to its tailored reduction potential, F2DEE participates in early-stage electrochemical reduction on reactive metal surfaces. This contributes to the formation of a flexible, hybrid inorganic-organic Solid Electrolyte Interphase (SEI) containing dispersed lithium fluoride (LiF) domains that help suppress dendrite propagation. (3) Polysulfide Compatibility (Li-S Systems): Its balanced polarity provides favorable wetting and moderate dissolution characteristics toward lithium polysulfide intermediates, supporting active material utilization in sulfur cathodes while helping mitigate the shuttle effect when paired with secondary co-solvents.

Its primary electrochemical domains are: (1) Low-Temperature Lithium-Metal Batteries: Integrated into liquid electrolyte formulations to ensure high ionic conductivity and stable stripping/plating behavior in cold-climate or high-rate operational environments. (2) Lithium-Sulfur (Li-S) Chemistries: Utilized as a functional co-solvent to optimize separator wettability and maintain active reaction kinetics in sulfur-based energy storage systems.

Part Number	CBESAF2DEE (C-BESA-F2DEE)
CAS	63938-33-0
Chemical Formula	C6H12F2O2
Appearance	Colorless liquid
Purity	>99.0%
Molecular Weight	154.16 g/mol
Package Size	10 g, 25 g, and 50 g/bottle

Notes: Please store the F2DEE liquid in the dry place (glovebox is the best).

References: 

1. D. Ruan, et al. Solvent versus Anion Chemistry: Unveiling the Structure-Dependent Reactivity in Tailoring Electrochemical Interphases for Lithium-Metal Batteries, JACS Au (2023) 3 (3): 953–963.
2. E. Zhang, et al. Monofluorinated acetal electrolyte for high-performance lithium metal batteries, 2025, DOI: 10.1073/pnas.2418623122