Ionic Liquids have emerged as the most promising candidates for use as Li battery electrolyte because of their negligible vapor pressure, low flammability and large electrochemical window. The questions that need be addressed are: how fast will the Li+ ions be able to diffuse in IL ? Will the IL represent a “bottleneck” or will it sustain high enough Li flow rates for the available cathode capacities? What is the optimum concentration of the anions that in principle can slow down the Li+.
In the present study we investigate the Li diffusion in a number of ionic liquids mixed with LiTFSI in different ratios, employing the state-of-the-art, many-body, polarizable APPLE&P force field for IL. The predicted self-diffusion coefficients, conductivity, and viscosity provided by simulations will be confronted with the experimental results to consolidate the predictive power of the selected approach for further IL-Li compositions refinements.
