Using the range of activation energies obtained from the linewidth narrowing (0.21-0.29 eV), the correlation factor (f = 0.06) and assuming an attempt frequency ν * of 1•10 13 Hz, a range for the ion conductivity at 300 K as probed by Li NMR was calculated (Table ). Table summarizes the activation energies and RT conductivities obtained from different techniques. We observe reasonable agreement between our NMR measurements and the jump-analysis of our AIMD simulations (Table ). The activation energy obtained from the tracer-analysis of our AIMD simulations is 0.08 eV larger than that of the jump-analysis. This is most likely a consequence of the difference in how the mean square displacement is calculated (see Methodology) which may affect the respective temperature dependence of DJ and Dtr. Diffusivities obtained from the jump-analysis (DJ) tend to be overestimates because the jump-analysis captures locally confined motion that does not effectively contribute to macroscopic diffusion. Activation energies and conductivities obtained from the traceranalysis (Dtr) of AIMD simulations thus better compare to the bulk properties of materials measured by EIS. Interestingly, the activation energy obtained from EIS is by 0.1 eV larger than the activation energy obtained from our AIMD tracer analysis. We would like to bring forward two conceivable explanations for this discrepancy. (i) The length scale probed by EIS is 5 orders of magnitude larger than the one probed in our AIMD simulations (Table ). EIS may potentially capture a diffusion limitation occurring at the mesoscale of our LNCl pellets. Such a diffusion limitation may for example arise from potential amorphous impurities in our LNCl pellets that would not be detected by XRD. (ii) A second explanation for the discrepancy between our AIMD tracer-analysis and our EIS experiments may be diffusion limiting Cl4 sites and/or Cl-Cl edges in the bulk of our LNCl pellets: Our AIMD analysis shows a poor affinity for jumps through Cl4-sites and Cl-Cl edges (Ea,jump>0. To investigate potential benefits of mechanical milling we processed LNCl-I for 4h in a planetary ball mill after solid-state synthesis. Samples prepared in this way are from now on referred to as LNCl-I-BM. LNCl-I remains stable during the milling as no impurity peaks are detected in the XRD of LNCl-I-BM. The XRD of LNCl-I-BM shows dramatic peak-broadening compared to LNCl-I (Figure ). Rietveld refinements show that the lattice parameter of LNCl-I is decreased from 5.39(6) Å to 5.37(6) Å after the mechanical milling process. Additionally, Williamson-Hall analysis (Figure ) shows that after milling the average crystallite size is dramatically reduced from the µm range to ~60 nm. Milling also imposes significant strain on the LNCl lattice so that we obtain a residual microstrain of Ɛ = 1.04 % for LNCl-I-BM.