To investigate the link between ionic transport and rate capability, we conducted PFG NMR measurements on various carbon materials saturated with 1 M TEABF4 (ACN) chosen to exhibit resolved in-pore and ex-pore environments in F spectra, which was critical for separating the dominant bulk electrolyte signal from the much weaker in-pore contribution (Figure ). The selected carbon materials represented a broad range of rate capabilities, graphene-like domain sizes , and pore size distributions (Figure ). Importantly, the shortrange effective diffusion coefficient, D " , did not show any clear correlation with the rate capability (Figure ). In contrast, the long-range effective diffusion, D ! , showed a clear correlation with the measured rate capability (Figure ): for carbon-electrolyte combinations with larger D ! , larger rate capabilities were obtained. Together, these results show that longrange ionic transport is much more important than short-range transport in determining supercapacitor charging rates. Interestingly, D ! does not correlate with the mesoporous specific surface area SSA (Figure ), which further supports the idea that other factors beyond mesoporosity are playing a significant role in determining ionic transport. These factors could include pore interconnectivity or the relative size of electrolyte molecules to the pore and pore constriction sizes. To evaluate the contribution of pore interconnectivity, we measured the tortuosity value in our samples (Figure ). For the studied carbon-electrolyte systems, we found pore network tortuosity values ranging from ca. 8 to 105 (Table , Figure ), which highlights the diversity in the long-range electrolyte transport in the different samples. The particularly high tortuosity values demonstrate that ionic transport can be limiting in some electrode materials, with a diffusion path length in the sample more than two orders of magnitude longer than diffusion in a straight line. Excitingly, we found a good correlation between the tortuosity parameter plotted against rate capability (Figure ), and overall, that higher tortuosity was associated with lower electrode performance at high current densities owing to the more indirect ionic transport pathways. The tortuosity values did not correlate with the microporous nor mesoporous specific surface area (Figure ), suggesting that, in addition to the pore sizes, the pore arrangements and how pores are connected are important considerations for fast charging performance.