Abstract: A method for the production of an electrochemical cell and an electrochemical cell stack is disclosed with annular electrolyte arranged in a pressure vessel. Such a cell is produced by providing an annular precursor already provided with the electrodes where the product is converted to the desired membrane/electrolyte by heating and oxidation. By using a pressure vessel, pressure can also be generated during the conversion. To this end the region outside the cell is provided with a fill material. A number of cells can be stacked on top of one another. With this arrangement, the anode of one cell can act as cathode of another cell by means of a Z-shaped configuration. Adjacent anodes/cathodes can be applied to one another by welding or can be of a Z-shaped design.