Image Number 3 for United States Patent #7352560.
The present subject matter includes a capacitor stack having a plurality of anode layers, and a plurality of cathodic metal substrates partially coated in a titanium coating. Cathode portions lacking titanium enable weld interconnections which are substantially free of titanium, improving capacitor properties. In some embodiments, anodes are interspersed among cathodes, and are electrically separated from the cathodes, with portions of cathode material attached to the welding area of the anode. These portions of the cathode material are no longer electrically connected to the cathode. As the anode and these cathode portions are welded and aged, leakage current is reduced due to improved oxide growth in the welding area due to the absence of titanium.