Simulation of coarse-grained ionic liquid models at the electrode-electrolyte interface

In the last few decades ionic liquids (ILs) have gained significant attention due to their unique physical and chemical properties. ILs are good candidates for battery electrolytes application due to low volatility, moderate reactivity, low flammability, and a wide liquid range than most organic solvents, thus imposing safer and higher-energy storage systems. Systems of ILs have been extensively studied experimentally and computationally. For instance, the most used all-atom molecular dynamics (MD) method delivers atomic-level details of IL systems for use in vast technical applications. MD method can handle systems of small length and time scale, and coarse-grained (CG) simulation techniques may be used to extend all-atom computational simulations up to a mesoscale level. The present work is focused on studying CG ILs behavior at electrode-electrolyte interface. Selected ILs were confined between ideal graphite electrodes and their density profiles were calculated for various potentials. Results of this research agree with the reference all-atom MD simulations. Implementation of CG models allowed to increase a size of the system by an order of magnitude when compared to the reference all-atom approach allowing more realistic representation of the ILs at electrode-electrolyte interfaces. Research results represented in this work open opportunities to advance our knowledge in liquid-state storage systems with modified electrodes structure for high power capacity battery development.