Solid electrolytic capacitor containing a pre-coat and intrinsically conductive polymer

A solid electrolytic capacitor comprising a capacitor element, wherein the capacitor element comprises:

• an anode body;
• a dielectric that overlies the anode body;
• a pre-coat that overlies the anode body, wherein the pre-coat is formed from a monoaminofunctional silane that is a primary amine;
• a solid electrolyte that includes:
• at least one inner layer that overlies the pre-coat, is generally free of extrinsically conductive polymers, and contains an intrinsically conductive polymer containing repeating thiophene units of the following general formula (I):
• wherein,
• a is from 0 to 10;
• b is from 1 to 18;
• R is an optionally substituted C1-C6 linear or branched alkyl group or a halogen atom;
• and
• M is a hydrogen atom, an alkali metal, NH(R1)3, or HNC5H5, wherein R1 is each independently a hydrogen atom or an optionally substituted C1-C6 alkyl group;
• and
• at least one outer layer that overlies the inner layer, wherein the outer layer includes conductive polymer particles containing a complex of an extrinsically conductive thiophene polymer and a counterion;
• and
• an external polymer coating that overlies the solid electrolyte and includes conductive polymer particles containing a complex of an extrinsically conductive thiophene polymer and a counterion;
• wherein the capacitor exhibits a charge-discharge capacitance after being subjected to 5,000 cycles of a surge voltage and an initial capacitance prior to being subjected to the 5,000 cycles of the surge voltage, wherein the ratio of the charge-discharge capacitance to the initial capacitance is from about 0.9 to 1.