An electrolytic capacitor is a polarized capacitor whose anode or positive plate is made of a metal that form an insulating oxide layer through anodization, this oxide layer act as the dielectric of capacitor a solid, liquid or gel electrolyte cover the surface of this oxide layer. Serving as cathode or negative plate of the capacitor due to their very thin dielectric oxide layer and enlarged anode surface electrolytic capacitor have a much higher capacitor voltage product per unit volume.