Unitary lid for an electrochemical cell

A unitary lid for the casing of an electrochemical, is described. The lid has a terminal lead ferrule and a fillport formed from a single blank in a machining process. The lid does not require any welding except for securing it to the open end of a casing container. This helps the lid contribute to the cell's volumetric efficiency, which is especially important for cells powering implantable medical device.