Fig. 2: Time evolution of average Li concentration profiles.

a–d The average Li concentration profiles along the z axis for the aSi/Li, cSi(100)/Li, cSi(110)/Li, and cSi(111)/Li interface models. Each line presents the average concentration results calculated from 50 configurations, which are sampled at equal time intervals within a period of 50 ps. 100 lines in total are included for the cSi(110)/Li model during the 5 ns DeePMD trajectories. Fractional concentration (Li/Li+Si) means the ratio of the number of Li atoms to the total number of Li and Si atoms in each Li-Si interface model. The color representations for the time evolutions of Li fractional concentrations from 0 to 5 ns is illustrated in the inset figure of panel (a), and this pattern applies to (b–d) as well. The light blue regions and the corresponding distance values on the top in (a–d) show the lengths of Li-Si interdiffusion regions after 5 ns simulations. Note: the spatial position of simulation cells along the z axis is represented by bin numbers.