Patent ID: 8888967

Claim:
A system for creating a porous anode foil, comprising: an electrochemical bath containing an electrochemical drilling (ECD) solution initially comprising 10 to 5000 PPM of a surface passivator, and about 0.1% by weight of an acid, wherein the ECD solution has a pH within a range of 0.5 to 3, the bath configured to receive an etched foil sheet in a substantially continuous manner such that a portion of said etched foil sheet is in contact with the ECD solution in the bath; a charge source connected to the bath to cause an electrochemical reaction in the bath; a feed reservoir fluidly connected to the electrochemical bath, the feed reservoir containing an ECD replenishment solution comprising 10 to 5000 PPM of the surface passivator, and about 0.1% by weight of the acid, wherein the ECD replenishment solution has a pH within a range of 0.5 to 3; a waste reservoir fluidly connected to the electrochemical bath for receiving ECD solution removed from the bath; and a pump for adding the ECD replenishment solution to the bath from the feed reservoir so as to maintain the pH of the ECD solution within a range of 0.5 to 3.