An capacitor, comprising a capacitor stack, including one or more substantially planar anode layers, and one or more substantially planar cathode layers, the capacitor including a case with a first opening and a second opening, the first opening sized for passage of the capacitor stack and the second opening defined by walls having a first thickness. Additionally, the capacitor has a cover substantially conforming to the first opening and sealingly connected to the first opening, and a plate substantially conforming to the second opening, the plate adapted for attachment of a terminal, and sealingly connected to the second opening. The plate has a second thickness which is approximately greater than the first thickness of the walls defining the second opening. The capacitor stack is disposed in the case, and the terminal is in electrical connection with the case and at least one capacitor electrode.