after forming a dielectric oxide on the rough anode structure, a counter electrode has to match the rough insulating oxide surface. this is accomplished by the electrolyte, which acts as the cathode electrode of an electrolytic capacitor. there are many different electrolytes in use. generally they are distinguished into two species, “non-solid” and “solid” electrolytes. as a liquid medium which has ion conductivity caused by moving ions, non-solid electrolytes can easily fit the rough structures. solid electrolytes which have electron conductivity can fit the rough structures with the help of special chemical processes like pyrolysis for manganese dioxide or polymerization for conducting polymers.