Battery knowledge · Electrolytes and separators

Fluorinated electrolyte

An electrolyte whose solvents largely carry fluorine — fluorinated carbonates such as FEC, or fluorinated ethers used as diluents. Fluorine draws electron density from the solvent, raising its oxidation stability towards 5 V, and its reduction leaves a lithium-fluoride-rich SEI. That suits high-voltage cathodes and lithium metal, at higher cost and with PFAS concerns.

Also called
fluorinated solvent, all-fluorinated electrolyte

Example

Electrolytes and separators: an example situation

Greater liquid uptake may improve wetting while changing mechanical behavior. Several properties define separator performance.

Read Fluorinated electrolyte alongside Electrochemical stability window in this context. The potential range within which an electrolyte is neither reduced nor oxidised. Carbonate electrolytes are only stable from about 1 V to 4.3 V vs Li/Li⁺; graphite operates below that, which is why the SEI, not thermodynamics, keeps the cell alive.

Use in Lemonergy

Connect transport with electronic isolation.

This is a reference concept. No executable Lemonergy block has been verified for this term.

References & further reading

Further reading on this topic

These sources provide broader context; they are not presented as citations for every statement in this entry.

  1. Electrolytes and Interphases in Li-Ion Batteries and Beyond

    Kang Xu · Chemical Reviews · 2014

    Topic background · Electrolyte salts, solvents, additives and electrode interphases.