A highly concentrated ether electrolyte for efficient Na-ion half cells

Titel in Übersetzung: Ein hochkonzentrierter Etherelektrolyt für effiziente Na-Ionen Halbzellen

Publikation: KonferenzbeitragPoster

Abstract

Na-ion batteries are amongst the most appealing alternatives to Li-ion batteries due to a similar intercalation chemistry and lower cost. Novel Na-ion chemistries are often assessed in half cells that contain Na-metal counter and reference electrodes (Figure 1). These electrodes are highly reactive and require a passivation layer to work, which is formed from electrolyte decomposition products. Recently, however, the passivation layer of standard carbonate electrolytes on sodium metal was found to be rather instable, raising questions about the reliability of both Na-ion half cells and other low voltage anodes. [1]

This work presents a dimethoxyethane (DME) / sodium bis(fluorosulfonyl)imide (NaFSI) (2/1 (n/n)) electrolyte that forms a stable and resilient passivation layer on sodium metal, as indicated by highly reversible sodium plating/stripping. Further investigation of the passivation layers by post-mortem FTIR and 1H-NMR analysis reveals that conventional organic carbonate based electrolytes decompose to organic salts such as sodium ethyl dicarbonate. In contrast, the DME/NaFSI electrolyte forms ethereal and alkoxide species as well as inorganic salts derived from the FSI anion. These compounds ensure sodium metal passivation and thereby enable more reliable and efficient testing in Na-ion half cells.
Originalspracheenglisch
PublikationsstatusVeröffentlicht - 27 Sep 2016
Veranstaltung2nd Graz Battery Days - Graz, Österreich
Dauer: 27 Sep 201628 Sep 2016

Konferenz

Konferenz2nd Graz Battery Days
LandÖsterreich
OrtGraz
Zeitraum27/09/1628/09/16

Fields of Expertise

  • Advanced Materials Science

Treatment code (Nähere Zuordnung)

  • Basic - Fundamental (Grundlagenforschung)

Projekte

  • 1 Abschlussdatum

Dieses zitieren

Schafzahl, L., Wilkening, M., & Freunberger, S. (2016). A highly concentrated ether electrolyte for efficient Na-ion half cells. Postersitzung präsentiert bei 2nd Graz Battery Days, Graz, Österreich.