Pressure electrolyser and method for operating one such electrolyser

A pressurized electrolysis apparatus having a pressure reservoir (2) and an electrolysis cell block (3) disposed in the pressure vessel (2), which is joined together to form a plurality of electrolysis cells (4). The electrolysis cells (4) each have anodes (11) and cathodes (12), and an electrolyte system for conducting anolytic to the anodes (12) and catholite conducting the cathodes (12), and wherein the electrolysis cell block (3) (2) is sealed with a sealing casing (5). The housing (5) of the electrolyzing cell block (3) forms at least two spaces (7, 8) with the pressure reservoir (2) forming portions of the electrolytic circulation system, and which are bounded by the housing (5) against the electrolysis cells (4) and by the pressure vessel (2) in the environment eye. The spaces (7, 8) form part of the one-catholyte circuitry separately separated from one another and separate from each other separated spaces (7), while the other cathode-cycle is separated from each other by separating spaces (8). HE