%0 Journal Article
%A Wagner, Ralf
%A Korth, Martin
%A Streipert, Benjamin
%A Kasnatscheew, Johannes
%A Gallus, Dennis R.
%A Brox, Sebastian
%A Amereller, Marius
%A Cekic-Laskovic, Isidora
%A Winter, Martin
%T Impact of Selected LiPF $_{6}$ Hydrolysis Products on the High Voltage Stability of Lithium-Ion Battery Cells
%J ACS applied materials & interfaces
%V 8
%N 45
%@ 1944-8252
%C Washington, DC
%I Soc.
%M FZJ-2017-02803
%P 30871 - 30878
%D 2016
%X Diverse LiPF6 hydrolysis products evolve during lithium-ion battery cell operation at elevated operation temperatures and high operation voltages. However, their impact on the formation and stability of the electrode/electrolyte interfaces is not yet investigated and understood. In this work, literature-known hydrolysis products of LiPF6 dimethyl fluorophosphate (DMFP) and diethyl fluorophosphate (DEFP) were synthesized and characterized. The use of DMFP and DEFP as electrolyte additive in 1 M LiPF6 in EC:EMC (1:1, by wt) was investigated in LiNi1/3Mn1/3Co1/3O2/Li half cells. When charged to a cutoff potential of 4.6 V vs Li/Li+, the additive containing cells showed improved cycling stability, increased Coulombic efficiencies, and prolonged shelf life. Furthermore, low amounts (1 wt % in this study) of the aforementioned additives did not show any negative effect on the cycling stability of graphite/Li half cells. DMFP and DEFP are susceptible to oxidation and contribute to the formation of an effective cathode/electrolyte interphase as confirmed by means of electrochemical stability window determination, and X-ray photoelectron spectroscopy characterization of pristine and cycled electrodes, and they are supported by computational calculations.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000388429600024
%R 10.1021/acsami.6b09164
%U https://juser.fz-juelich.de/record/828986