Separators for Li-Ion and Li-Metal Battery Including Ionic Liquid Based Electrolytes Based on the TFSI− and FSI− Anions

Kirchhöfer M, Von Zamory J, Paillard E, Passerini S

Forschungsartikel (Zeitschrift) | Peer reviewed

Zusammenfassung

The characterization of separators for Li-ion or Li-metal batteries incorporating hydrophobic ionic liquid electrolytes is reported herein. Ionic liquids made of N-butyl-N-methylpyrrolidinium (PYR14+) or N-methoxyethyl-N-methylpyrrolidinium (PYR12O1+), paired with bis(trifluoromethanesulfonyl)imide (TFSI−) or bis(fluorosulfonyl)imide (FSI−) anions, were tested in combination with separators having different chemistries and morphologies in terms of wetting behavior, Gurley and McMullin number, as well as Li/(Separator + Electrolyte) interfacial properties. It is shown that non-functionalized microporous polyolefin separators are poorly wetted by FSI−-based electrolytes (contrary to TFSI−-based electrolytes), while the ceramic coated separator Separion® allows good wetting with all electrolytes. Furthermore, by comparing the lithium solid electrolyte interphase (SEI) resistance evolution at open circuit and during cycling, depending on separator morphologies and chemistries, it is possible to propose a scale for SEI forming properties in the order: PYR12O1FSI > PYR14FSI > PYR14TFSI > PYR12O1TFSI. Finally, the impact the separator morphology is evidenced by the SEI resistance evolution and by comparing Li electrodes cycled using separators with two different morphologies.

Details zur Publikation

FachzeitschriftInternational Journal of Molecular Sciences ( Int J Mol Sci)
Jahrgang / Bandnr. / Volume15
Ausgabe / Heftnr. / Issue8
Seitenbereich14868-14890
StatusVeröffentlicht
Veröffentlichungsjahr2014
Sprache, in der die Publikation verfasst istEnglisch
DOI10.3390/ijms150814868
Link zum Volltexthttps://www.mdpi.com/1422-0067/15/8/14868

Autor*innen der Universität Münster

Hoffmeyer, Marija
Institut für Physikalische Chemie