Identification of sodiation mechanisms in graphite-based negative electrodes by molecular dynamics simulations combined with potential of mean force.

In this study, we presented a theoretical investigation focused on the free energy barriers associated with Na + intercalation in various negative electrode morphologies based on graphite immersed in the [Pyr 14 ][Tf 2 N] ionic liquid. Additionally, we explored the influence of triglyme on the co-intercalation process. Our findings reveal that larger interlayer distances effectively reduce the energy barrier for sodiation. However, this also promotes the intercalation of [Pyr 14 ] + ions and decreases the population of sodium-ions within the electrode. We observed the co-intercalation mechanism in all electrode morphologies, but the interlayer distance significantly impacts this behavior. Therefore, using electrode materials with interlayer distances slightly larger than those of graphite shows promise for enhancing Na + intercalation. Nevertheless, when designing the electrolyte, careful consideration should be given to the size and shape of the cation in the ionic liquid to prevent unintended intercalation events. [Display omitted] [ABSTRACT FROM AUTHOR]