In an aspect, a hydrogen separation unit includes an electrochemical cell stack that includes a separator stack located in between an anode side and a cathode side; a mixed gas conduit for receiving a mixed gas stream to the anode side; an anode removal conduit for removing a helium rich stream from the anode side; and a cathode removal conduit for removing a hydrogen rich stream from the cathode side. The separation stack includes a plurality of electrochemical cells, each of which includes a proton exchange membrane located in between an anode and a cathode. The proton exchange membrane can include a cation. The separation stack can be a cascading separation stack.

Disclosed are a catalyst for an electrochemical cell and a method of manufacturing the catalyst. The catalyst includes a support, a first catalyst supported on the support, wherein the first catalyst is a catalyst for hydrogen oxidation reaction (HOR) or oxygen reduction reaction (ORR), a second catalyst supported on the first catalyst, wherein the second catalyst is a catalyst for oxygen evolution reaction (OER), and a protective layer formed on the first catalyst and the second catalyst.

A composite for a porous transport layer may include a particulate substrate including at least one selected from a group consisting of an oxide of a first metal and a second metal, and nanoparticles of a third metal formed on a surface of the particulate substrate, a sintered body thereof, and a method for preparing the same.

A design of and the process for forming a rigidly bonded metal supported electro-chemical device stack is provided. The electro-chemical device stack can be a solid oxide fuel cell or solid oxide electrolysis stack. The stack comprises multiple planar cells connected in serial by planar metal interconnects. The cells have metal support layers on both anode and cathode sides. The interconnect has gas channels embedded. Thin ceramic electro-chemical active electrodes and electrolyte are sandwiched between the metal support layers. The cells and interconnects are rigidly bonded to form a rigid body stack. The process comprises the steps of a). forming metal supported electro-chemical device cells with metal supports on both anode and cathode sides, b). sealing the peripherals of porous cell layers with an electrically insulating sealing material such as glass. c). bonding the cells and interconnects through commonly used metal-to-metal bonding methods, such as brazing or laser welding.

An electrolysis cell includes an anode chamber and a cathode chamber separated by an ion-exchange membrane. The electrolysis cell includes an anode, a cathode, and a cathode current distributor. The anode, the ion-exchange membrane, the cathode, and the cathode current distributor are in direct touching contact in the mentioned order. Flexibly resilient holding elements are arranged on the other side of the anode and/or on the other side of the cathode current distributor. The flexibly resilient holding elements exert a contact pressure on the anode and/or on the cathode current distributor. The flexibly resilient holding elements have annular elements, the axis of which is oriented in the height direction of the electrolysis cell. By means of the flexibly resilient and in part also plastically deforming annular elements, effective mechanical contact pressure of the ion-exchange membrane against the oxygen-depolarized cathode is achieved.

An electrolysis cell includes an anode chamber and a cathode chamber separated by an ion-exchange membrane. The electrolysis cell includes an anode, a cathode, and a cathode current distributor. The anode, the ion-exchange membrane, the cathode, and the cathode current distributor are in direct touching contact in the mentioned order. Flexibly resilient holding elements are arranged on the other side of the anode and/or on the other side of the cathode current distributor. The flexibly resilient holding elements exert a contact pressure on the anode and/or on the cathode current distributor. The flexibly resilient holding elements have annular elements, the axis of which is oriented in the height direction of the electrolysis cell. By means of the flexibly resilient and in part also plastically deforming annular elements, effective mechanical contact pressure of the ion-exchange membrane against the oxygen-depolarized cathode is achieved.

A hydrogen system includes: a compressor including at least one cell that includes an electrolyte membrane, an anode catalyst layer provided on one principal surface of the electrolyte membrane, a cathode catalyst layer provided on another principal surface of the electrolyte membrane, an anode gas diffusion layer provided on the anode catalyst layer and including a porous sheet containing a metal, and a cathode gas diffusion layer provided on the cathode catalyst layer, and a voltage applicator that apples a voltage between the anode catalyst layer and the cathode catalyst layer, wherein the compressor that generates compressed hydrogen by causing the voltage applicator to apply the voltage to move hydrogen in hydrogen-containing gas supplied to an anode to the cathode via the electrolyte membrane; and a controller that causes the voltage applicator to apply the voltage after shutdown or at startup.

A metal support for an electrochemical element where the metal support includes a plate face, has a plate shape as a whole, and has a warping degree of 1.5×10.sup.−2 or less determined by calculating a least square value through the least squares method using at least three points in the plate face of the metal support, calculating a first difference between the least square value and a positive-side maximum displacement value on a positive side with respect to the least square value and a second difference between the least square value and a negative-side maximum displacement value on a negative side that is opposite to the positive side with respect to the least square value, and dividing the sum of the first difference and the second difference by a maximum length of the plate face of the metal support that passes through a center of gravity.

The invention relates to a bipolar plate assembly (1) for forming an electrolysis or fuel cell stack and to the use of a bipolar plate assembly and an electrolysis or fuel cell stack with a plurality of bipolar plate assemblies.

The invention relates to a bipolar plate assembly (1) for forming an electrolysis or fuel cell stack and to the use of a bipolar plate assembly and an electrolysis or fuel cell stack with a plurality of bipolar plate assemblies.