An electrochemical cell having a cell package made of a metallic material to allow the cell package to be sealed by welding, even when contaminated. The electrochemical cell further includes an electrode cell stack and a metallic cell package having a base portion and a lid portion which are welded to each other (peripheral seam) to define an enclosure. The cell package includes a first section for receiving the cell stack and a second section having an inlet port and a degassing port which communicate with the first section. The lid portion is welded to the base portion to form a weld seam located between the first and second sections to seal off the first section from the second section. The weld seam extends from the peripheral seam on a first side of the cell package to the peripheral seam on a second side of the cell package.