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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 a

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° C. or more.

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What is claimed is: 1. A wet electrolytic capacitor comprising: an anode, wherein the anode includes tantalum, niobium, or an electrically conductive oxide thereof; a dielectric film formed over and within the anode through anodization of the anode; a cathode containing a coating disposed over a su

What is claimed is: 1. A wet electrolytic capacitor comprising: an anode, wherein the anode includes tantalum, niobium, or an electrically conductive oxide thereof; a dielectric film formed over and within the anode through anodization of the anode; a cathode containing 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 being formed from an amorphous polymer having a glass transition temperature of about 100° C. or more, wherein the binder is in the form of particles having a D90 particle size distribution of about 150 micrometers or less; and a working electrolyte disposed between the cathode and the anode, wherein the working electrolyte contains an aqueous solution that includes an acid, wherein the working electrolyte comprises a nitroaromatic depolarizer in an amount of from about 10 to about 200 parts per million of the electrolyte, and wherein the electrolyte has a pH of from about 5.0 to about 8.0. 2. The wet electrolytic capacitor of claim 1, wherein the amorphous polymer has a glass transition temperature of about 150° C. or more. 3. The wet electrolytic capacitor of claim 1,wherein the amorphous polymer has a glass transition temperature of about 250° C. or more. 4. The wet electrolytic capacitor of claim 1, wherein the amorphous polymer is a thermoplastic polyimide. 5. The wet electrolytic capacitor of claim 4, wherein the polyimide is a poly(amide-imide), poly(ether-imide), or a combination thereof. 6. The wet electrolytic capacitor of claim 5, wherein the polyimide is a poly(amide-imide) formed from trimellitic acid or a derivative thereof, and an aromatic diamine. 7. The wet electrolytic capacitor of claim 1, wherein the binder is in the form of particles having a D90 particle size distribution of about 75 micrometers or less. 8. The wet electrolytic capacitor of claim 1, wherein the binder constitutes from about 1 wt. % to about 40 wt. % of the coating. 9. The wet electrolytic capacitor of claim 1, wherein the binder constitutes from about 5 wt. % to about 20 wt. % of the coating. 10. The wet electrolytic capacitor of claim 1, wherein the electrochemically-active particles include a metal, metal oxide, carbonaceous particles, or a combination thereof. 11. The wet electrolytic capacitor of claim 1, wherein the electrochemically-active particles include activated carbon. 12. The wet electrolytic capacitor of claim 1, wherein the electrochemically-active particles constitute from about 50 wt. % to about 99 wt. % of the coating. 13. The wet electrolytic capacitor of claim 1, wherein the electrochemically-active particles constitute from about 70 wt. % to about 95 wt. % of the coating. 14. The wet electrolytic capacitor of claim 1, wherein the coating further comprises a conductive filler. 15. The wet electrolytic capacitor of claim 1, wherein the current collector comprises a metal. 16. The wet electrolytic capacitor of claim 1, wherein the anode includes tantalum. 17. The wet electrolytic capacitor of claim 1, wherein the anode includes an electrically conductive oxide of niobium. 18. The wet electrolytic capacitor of claim 17, wherein the dielectric film includes niobium pentoxide. 19. The wet electrolytic capacitor of claim 18, wherein the electrically conductive oxide has an atomic ratio of niobium to oxygen of 1:less than 1.5. 20. The wet electrolytic capacitor of claim 18, wherein the electrically conductive oxide has an atomic ratio of niobium to oxygen of 1:1.0±0.2. 21. The wet electrolytic capacitor of claim 1, wherein the pH of the electrolyte is from about 5.5 to about 7.5. 22. The wet electrolytic capacitor of claim 1, wherein the pH of the electrolyte is from about 6.0 to about 7.5. 23. The wet electrolytic capacitor of claim 1, wherein water constitutes from about 30 wt. % to about 90 wt. % of the working electrolyte. 24. The wet electrolytic capacitor of claim 1, wherein the working electrolyte has a freezing point of about-20° C. or less and a boiling point of about 85° C. or more. 25. The wet electrolytic capacitor of claim 1, wherein the nitroaromatic depolarizer includes an alkyl-substituted nitrobenzoic acid, an anhydride or salt thereof, or mixtures of any of the foregoing. 26. The wet electrolytic capacitor of claim 25, wherein alky-substituted ntrobenzoic acid includes 2-methyl-3-nitrobenzoic acid, 2-methyl-6-nitrobenzoic acid, 3-methyl-2-nitrobenzoic acid, 3-methyl-4-nitrobenzoic acid, 3-methyl-6-nitrobenzoic acid, or 4-methyl-3-nitrobenzoic acid. 27. The wet electrolytic capacitor of claim 1, wherein the nitroaromatic depolarizer constitutes from about 20 to about 150 parts per million of the electrolyte.