US Patent 9406445 Solid electrolytic capacitor with enhanced wet-to-dry capacitance

A capacitor for use in relatively high voltage environments is provided. During formation, anodization may be carried out in a manner so that the dielectric layer possesses a relatively thick portion that overlies an external surface of the anode and a relatively thin portion that overlies an interior surface of the anode. In addition to employing a dielectric layer with a differential thickness, the solid electrolyte is also formed from the combination of pre-polymerized conductive polymer particles and a hydroxy-functional nonionic polymer.