The CPs biggest advantage over other possible cathode materials is the reversibility of the insertion of charge carriers due to the minimal structural changes upon intercalation. Most other materials bind especially multivalent ions too strongly to be deintercalated during the charging process. The CP however has a metallic ground state and thus shields the charge carrier so effectively that it can easily shield divalent charges. The sulfur cage can also be substituted with selenide and tellurium, but these elements are toxic and therefore can lead to safety problems which makes them harder to handle.