Qualitatively, the large SAXS/WAXS intensity increase at low and large scattering vectors q (Fig. , red to blue for increasing polarization) can be assigned to different contributions. The distinct intensity hump around 3 nm -1 has a shape comparable to the nanopore scattering contribution of the empty AC shown in Fig. . This can only be explained by large amounts of a high-density compounds accumulating in its characteristic nanopores. The electron densities ρ of carbon skeleton and electrolyte-filled nanopores (insert in Fig. ) point at the formation of solid iodine, since dissolved polyiodides alone could not account for the necessary electron density increase.