%0 Journal Article
%A Murmann, Patrick
%A Mönnighoff, Xaver
%A von Aspern, Natascha
%A Janssen, Pia
%A Kalinovich, Nataliya
%A Shevchuk, Michael
%A Kazakova, Olesya
%A Röschenthaler, Gerd-Volker
%A Cekic-Laskovic, Isidora
%A Winter, Martin
%T Influence of the Fluorination Degree of Organophosphates on Flammability and Electrochemical Performance in Lithium Ion Batteries: Studies on Fluorinated Compounds Deriving from Triethyl Phosphate
%J Journal of the Electrochemical Society
%V 163
%N 5
%@ 1945-7111
%C Pennington, NJ
%I Electrochemical Soc.
%M FZJ-2017-07606
%P A751 - A757
%D 2016
%X Three symmetric substances originating from triethyl phosphate were specifically synthesized with varying degree of fluorination at the side chain. Different concentrations of each phosphate were evaluated as co-solvent with regard to their flammability and the electrochemical cycling performance. With higher degree of fluorination and a higher amount of the phosphate in the electrolyte, the self-extinguishing time (SET), a value to determine and compare the flammability of electrolytes, could be significantly lowered to yield a non-flammable electrolyte mixture. A specifically designed SET device is introduced, which offers more accurate results due to lowered standard deviations by minimizing random and systematic errors. As the application of phosphates as co-solvents results in a trade-off in cycling performance, a thorough determination in regard to the ionic conductivity, the anodic oxidation stability and the compatibility with anode and cathode material was carried out in half- and full-cells. The manuscript strives to establish a deeper understanding of the influence that the utilization of phosphates as co-solvents entail with special focus on the fluorination degree. It could be shown that the partially fluorinated phosphate offers the best cycling results and therefore the lowest trade-off in performance, while a severe improvement in SET could be achieved compared to the reference electrolyte.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000370866700023
%R 10.1149/2.1031605jes
%U https://juser.fz-juelich.de/record/840040