BACKGROUND OF THE INVENTION

The present invention generally relates to a capacitor and, more particularly, to a capacitor capable of powering an implantable medical device, such as a cardiac defibrillator.

More specifically, the present invention relates to casings for implantable capacitors, the capacitors being particularly adapted for powering implantable medical devices. Accordingly, the casings have contoured surfaces to more closely conform to body contours. This means that the anode housed in the casing must also have a contoured shape substantially matching that of the casing. Capacitors with contoured casings facilitate implantation in areas of a body that were heretofore not possible because of geometrical limitations.

SUMMARY OF THE INVENTION

In general, an electrochemical/electrolytic hybrid or an electrolytic capacitor consists of an anode and a cathode that are separated from each other by an ionically conductive working electrolyte or a porous separator impregnated with a working electrolyte. The anode is made of a valve metal, such as tantalum, aluminum, niobium, or titanium, that has been pressed into a shaped pellet and sintered at a relatively high temperature for a period that is sufficient to coalesce the pressed valve metal material into a cohesive body. The sintered valve metal pellet is then anodized in an anodizing electrolyte to form a film of the corresponding oxide serving as a dielectric on the valve metal. The final anodizing voltage determines the dielectric oxide film thickness, which relates to the rated capacity of the thusly formed anode.

These and other aspects of the present invention will become more apparent to those skilled in the art by reference to the following description and to the appended drawings.

