A capacitor in an implantable medical device is provided. The capacitor having an anode, a cathode including a conductive coating, and an electrolyte disposed and in contact between the anode and the cathode. The conductive coating is composed of a chemisorbed conductive layer that is interposed between a metal substrate and a layer including a mix of activated carbon with a metal-oxide and electrolyte disposed and in contact between the anode and the cathode.
A working electrolyte for use in a wet electrolytic capacitor is provided. The electrolyte is relatively neutral and has a pH of from about 5.0 to about 8.0, in some embodiments from about 5.5 to about 7.5, and in some embodiments, from about 6.0 to about 7.5. Despite possessing a neutral pH level, the electrolyte is nevertheless electrically conductive. For instance, the electrolyte may have an electrical conductivity of about 10 milliSiemens per centimeter ("mS/cm") or more, in some embodiments about 30 mS/cm or more, and in some embodiments, from about 40 mS/cm to about 100 mS/cm, determined at a temperature of 25.degree. C.
A wet electrolytic capacitor that comprises an anode, cathode, and working electrolyte is provided. The cathode contains a coating disposed over a surface of a current collector, wherein the coating comprises a plurality of electrochemically-active particles and a binder. The binder is formed from an amorphous polymer having a glass transition temperature of about 100.degree. C. or more.