The present teachings provide methods of preparing an anode for use in a high volumetric energy density electrolytic capacitor. A lead wire is de-oxidized and sintered in a valve metal powder compact to form the anode. The de-oxidizing and sintering are conducted in the presence of a reactive metal having a stronger affinity for oxygen than the valve metal powder. A residual reactive metal and at least one reactive metal reaction product are removed from the anode surface with a leaching process. Remaining residual reactive metal and reactive metal reaction products are redistributed by thermal processing. A capacitor containing the anode has an operating voltage greater than 90% of the forming voltage.
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