A comprehensive insight into the volumetric response of graphite electrodes upon sodium co-intercalation in ether-based electrolytes

Add time:08/24/2019    Source:sciencedirect.com

In this study, the interplay between the electrochemical behavior, structural modifications and volumetric changes of graphite-based negative electrodes for sodium ion batteries is evaluated. The electrolyte solvents chosen for this study are ethylene glycol dimethyl ether (DME), diethylene glycol dimethyl ether (DEGDME), triethylene glycol dimethyl ether (TriGDME), and tetraethylene glycol dimethyl ether (TEGDME) while the salt is sodium trifluoromethanesulfonate (NaOTf). The volume changes undergone upon co-(de)intercalation of the [Na-solvent]+ complexes are systematically investigated by means of in situ electrochemical dilatometry and correlated to the structural modification of the graphite crystalline lattice as detected by in situ X-ray diffraction. The expected staging mechanism upon co-intercalation, leading to the formation of stage-I graphite intercalation compound, is observed with all electrolytes. However, the various solvents play a substantial role on the reversibility of such structural changes in the first cycle. The effect of temperature is also investigated showing that the most stable electrochemical performance is observed with the TEGDME at room temperature, but with TriGDME at higher temperatures. Nonetheless, post-mortem scanning electron microscopy suggests that the surface layer forming after the first sodiation may dissolve in the following de-sodiation.

We also recommend Trading Suppliers and Manufacturers of Diethylene Glycol Dimethyl Ether (cas 111-96-6). Pls Click Website Link as below: cas 111-96-6 suppliers

Prev:Raman spectra of perdeuterated ethylene glycol dimethyl ether and Diethylene Glycol Dimethyl Ether (cas 111-96-6) and the molecular force field of oxyethylene compounds
Next:Molecular dynamics and experimental characterization of [BMIM][BF4] and [BMIM][PF6] with ether cosolvent binary mixtures)