Abstract: An electrolytic capacitor that contains an anodically oxidized anode that is incorporated with an additional metallic element is provided. More specifically, the metallic element is built into the valve metal pentoxide of the dielectric layer. In one particular embodiment, the addition of the metallic element results in a niobium pentoxide dielectric that contains closely packed units of O atoms, Nb6 octahedral, and metal atoms (“A”) that serve as counter cations. The use of relatively small electropositive metal atoms (A?) helps fill the tetrahedral (e.g., Al, Si, Ti, Mg, or Mn), octahedral (e.g., Nb, V, Mg, or Mn) and trigonal bipyramid (e.g., V, Nb) interstices of the crystals. The stability of capacitor leakage current may be improved by variation in this crystal structure.

Abstract: An electrolytic capacitor anode etched with an organic acid prior to anodic oxidation of the anode to create the dielectric layer. Without intending to be limited by theory, it is believed that the organic acid can etch away at least a portion of any oxides on the anode. This provides a relatively uniform surface for the creation of the dielectric, which in turn leads to a dielectric layer having a substantially uniform thickness and homogeneous amorphous structure and thus improved leakage current and stability. The organic acid may also have other residual benefits, such as removing any metallic impurities from the surface of the anode.

Abstract: An electrolytic capacitor anode treated with a surfactant during anodic oxidation is provided. Without intending to be limited by theory, it is believed that the surfactant may lower the surface tension of an electrolyte, which inhibits the clustering of grown oxides and allows the dielectric layer to become more homogeneous and uniformly spread over the anode body. The resulting dielectric layer may thus have a substantially homogeneous thickness, smooth surface, and improved leakage current stability.

Abstract: An electrolytic capacitor anode etched with an organic acid prior to anodic oxidation of the anode to create the dielectric layer. Without intending to be limited by theory, it is believed that the organic acid can etch away at least a portion of any oxides on the anode. This provides a relatively uniform surface for the creation of the dielectric, which in turn leads to a dielectric layer having a substantially uniform thickness and homogeneous amorphous structure and thus improved leakage current and stability. The organic acid may also have other residual benefits, such as removing any metallic impurities from the surface of the anode.

Abstract: An electrolytic capacitor anode treated with a surfactant during anodic oxidation is provided. Without intending to be limited by theory, it is believed that the surfactant may lower the surface tension of an electrolyte, which inhibits the clustering of grown oxides and allows the dielectric layer to become more homogeneous and uniformly spread over the anode body. The resulting dielectric layer may thus have a substantially homogeneous thickness, smooth surface, and improved leakage current stability.

Abstract: An electrolytic capacitor that contains an anodically oxidized anode that is incorporated with an additional metallic element is provided. More specifically, the metallic element is built into the valve metal pentoxide of the dielectric layer. In one particular embodiment, the addition of the metallic element results in a niobium pentoxide dielectric that contains closely packed units of O atoms, Nb6 octahedral, and metal atoms (“A”) that serve as counter cations. The use of relatively small electropositive metal atoms (A?) helps fill the tetrahedral (e.g., Al, Si, Ti, Mg, or Mn), octahedral (e.g., Nb, V, Mg, or Mn) and trigonal bipyramid (e.g., V, Nb) interstices of the crystals. The stability of capacitor leakage current may be improved by variation in this crystal structure.