The use of deuterated ethyl acetate in highly concentrated electrolyte as a low-cost solvent for in situ neutron diffraction measurements of Li-ion battery electrodes

Authors

R Petibon, Dalhousie University
Jing Li, Dalhousie University
Neeraj Sharma, The Bragg Institute, University of New South Wales
Wei Kong Pang, University of WollongongFollow
Vanessa K. Peterson, The Bragg Institute, Australian Nuclear Science And Technology OrganisationFollow
J Dahn, Dalhousie University

RIS ID

101573

Publication Details

Petibon, R., Li, J., Sharma, N., Pang, W. Kong., Peterson, V. K. & Dahn, J. R. (2015). The use of deuterated ethyl acetate in highly concentrated electrolyte as a low-cost solvent for in situ neutron diffraction measurements of Li-ion battery electrodes. Electrochimica Acta, 174 417-423.

Abstract

A low-cost deuterated electrolyte suitable for in situ neutron diffraction measurements of normal and high voltage Li-ion battery electrodes is reported here. Li[Ni_0.4Mn_0.4Co_0.2]O₂/graphite (NMC(442)/graphite) pouch cells filled with 1:0.1:2 (molar ratio) of lithium bis(fluorosulfonyl) imide (LiFSi):LiPF₆: ethyl acetate (EA) and LiFSi:LiPF₆:deuterated EA (d8-EA) electrolytes were successfully cycled between 2.8 V and 4.7 V at 40 C for 250 h without significant capacity loss, polarization growth, or gas production. The signal-to-noise ratio of neutron powder diffraction patterns taken on NMC(442) powder with a conventional deuterated organic carbonate-based electrolyte and filled with LiFSi:LiPF₆:d8-EA electrolyte were virtually identical. Out of all the solvents widely available in deuterated form tested in highly-concentrated systems, EA was the only one providing a good balance between cost and charge-discharge capacity retention to 4.7 V. The use of such an electrolyte blend would half the cost of deuterated solvents needed for in situ neutron diffraction measurements of Li-ion batteries compared to conventional deuterated carbonate-based electrolytes.