In this work, we present an investigation, combining experimental and computational modeling approaches, of the electrolyte/active material interfaces with focus on the EDL using LiFePO4 as a model electrode. In particular, the aim is to track the effect of the electrolyte solvent composition on the transient electrochemical behavior of the electrodes. A successful Swagelok® type setup probing interface liquid modifications is adapted for that purpose, in which the change of the solvent is made in-situ without cell disassembling. Such experimental cell allows the capture on how the electrolyte composition can affect the electrode potential dynamics. Coupling experimental results to computational modelling is addressed first for binary carbonate-based solvents (EC/DMC) with emphasize on the stability of the measurements using impedance spectroscopy. Mechanistic insights on the EDL structure and dynamics are also provided and discussed for ternary systems (EC/PC/DMC).
This work is funded by the French National Research Agency (ANR) through the project “ALIBABA” under the contract reference ANR-11-PRGE-0002.
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