Diglyme based electrolytes for sodium-ion batteries
Journal article, 2018
Sodium-ion batteries (SIBs) are currently being considered for large-scale energy storage. Optimization of SIB electrolytes is, however, still largely lacking. Here we exhaustively evaluate NaPF6 in diglyme as an electrolyte of choice, via both physicochemical properties and extensive electrochemical tests including half as well as full cells. Fundamentally, the ionic conductivity is found to be quite comparable to carbonate based electrolytes and to obey the fractional Walden rule with viscosity. We find Na metal to work well as a reference electrode and the electrochemical stability, evaluated potentiostatically for various electrodes and corroborated by DFT calculations, to be satisfactory in the entire voltage range 0-4.4 V. Galvanostatic cycling at C/10 of half and full cells using Na3V2(PO4)(3) (NVP) or Na3V2(PO4)(2)F-3 (NVPF) as cathodes and hard carbon (HC) as anodes indicates rapid capacity fading in cells with HC anodes, possibly originating in a lack of a stable SEI or by trapping of sodium. Aiming to understand this capacity fade further, we conducted a GC/MS analysis to determine electrolyte reduction products and to propose reduction pathways, concluding that oligomer and/or alkoxide formation is possible. Overall, the promising results should warrant further investigations of diglyme based electrolytes for modern SIB development, albeit avoiding HC anodes.
stability
batteries
degradation
sodium-ion
electrolytes
Author
Kasper Westman
Chalmers, Physics, Condensed Matter Physics
Romain Dugas
Collège de France
Piotr Jankowski
Chalmers, Physics, Condensed Matter Physics
Warsaw University of Technology
Centre national de la recherche scientifique (CNRS)
W. Wieczorek
Centre national de la recherche scientifique (CNRS)
Warsaw University of Technology
G. Gachot
Centre national de la recherche scientifique (CNRS)
University of Picardie Jules Verne
Mathieu Morcrette
Centre national de la recherche scientifique (CNRS)
University of Picardie Jules Verne
Enrique Irisarri
Institute of Material Science of Barcelona (ICMAB)
A. Ponrouch
Institute of Material Science of Barcelona (ICMAB)
M. R. Palacin
Institute of Material Science of Barcelona (ICMAB)
Centre national de la recherche scientifique (CNRS)
Jean-Marie Tarascon
Collège de France
Centre national de la recherche scientifique (CNRS)
Patrik Johansson
Chalmers, Physics, Condensed Matter Physics
Centre national de la recherche scientifique (CNRS)
ACS Applied Energy Materials
25740962 (eISSN)
Vol. 1 6 2671-2680Next generation batteries for hybrid and electric vehicles
Swedish Energy Agency (37671-1), 2013-12-01 -- 2017-12-31.
Na-Ion bAttery Demonstration for Electric Storage (NAIADES)
European Commission (EC) (EC/H2020/646433), 2015-01-01 -- 2018-12-31.
Driving Forces
Sustainable development
Areas of Advance
Transport
Energy
Materials Science
Subject Categories
Physical Sciences
Other Physics Topics
Chemical Sciences
Infrastructure
C3SE (Chalmers Centre for Computational Science and Engineering)
Chalmers Materials Analysis Laboratory
DOI
10.1021/acsaem.8b00360