They mention this material have inherent positive charge (they call it positive sponge)
and they claim accidentally getting strays of current from it.They mention a material is ion depleted.They never refer to it as a capacitor and only as a ``battery`` and they claim energy density impossible to achieve for a capacitors.Do you have any ideas how ion deficient material could be used to store charge?For example I know there exist some ion defects such as Frenkel pairs which could store charge and recombine.Could it be used to store electric energy in principle?Or maybe they take positively charged crystal and allow electrons to be attracted to it from somewhere and in this way receive energy?