align with those reported in other studies. However, the values of RH in micropores are smaller than the RH of individual water molecules (Figure ). Moreover, in some cases we found that the RH radii in micropores are smaller than those in the crystalline Li + -TFSI -(0.6+ 3.26 = 3.86 Å). Therefore, we could not directly apply equations 13 and 14 to determine the in-pore hydration number. At lower concentrations, more water molecules are available relative to the number of ions, allowing each ion to be fully solvated with strong hydration shells. These shells are partially stripped off during electrosorption in the narrow spaces of micro-and mesopores, which leads to greater desolvation of the ions (Scheme 1a). Additionally, the strong hydration shells around ions like cosmotropic Li⁺ contribute to efficient charge screening, resulting in lower Debye lengths (decreasing from 1 to 10 mol•kg -1 ). As these ions move towards porous carbon electrode surfaces during electrosorption, the hydration shells are partially removed to facilitate closer interactions between ions and pore walls. At lower concentrations, the relative dielectric constant is also higher (e.g. 68.17 at 1 mol•kg -1 ) , which supports stronger interactions between ions and solvents. This forces ions to lose part of their hydration shell to fit into narrow subnanopores, increasing hydrodynamic volume shrinkage and partial ion desolvation. In contrast, as the concentration increases to 15 and 20 mol•kg⁻¹, ion pairing becomes more prominent. This pairing reduces ionicity and the relative permittivity of the solution (e.g. 17.26 at 20 mol•kg⁻¹), thereby decreasing the hydrodynamic volume and desolvation number within micro-and mesopores. At these concentrations, the formation of EDL is hindered, because the reduced permittivity and increased ion pairing decrease effective ion distribution and charge storage.