IMPLANTABLE MEDICAL DEVICE CONSTRUCTION

An implantable medical device includes two conductive enclosures that are attached together, wherein the first enclosure contains electronics, and the second enclosure contains a power source. The second enclosure, all or a portion of which is located outside the first enclosure, includes an inner layer, an outer layer, and a header plate, all of which are configured to provide redundant sealing for the power source. The inner and outer layers, formed by separate metal sheets nested one within the other, are preferably in direct mechanical and electrical contact. The first sheet, which forms the inner layer, approximately conforms to a profile of the power source, located therein, and the second sheet, which forms the outer layer, conforms to a profile of the first sheet. An insulative housing, which contains connector contacts of the device, is directly secured to the first and second conductive enclosures, for example, by mounting brackets.