Methods and systems related to the field of electrolyzers are disclosed. An electrolyzer assembly is disclosed which includes a stack of cells, a plurality of polar plates in the stack of cells, a plurality of flow fields between the plurality of polar plates, a conduit fluidly connecting flow fields in the plurality of flow fields, an electrically conductive fluid in the conduit, a plurality of insulating layers arranged between a conductive surface of the plurality of flow fields and the conduit, and a plurality of openings in the plurality of insulating layers providing a plurality of fluid connections between the conduit and the plurality of flow fields.

Methods and systems related to the field of electrolyzers are disclosed. An electrolyzer assembly is disclosed which includes a stack of cells, a plurality of polar plates in the stack of cells, a plurality of flow fields between the plurality of polar plates, a conduit fluidly connecting flow fields in the plurality of flow fields, an electrically conductive fluid in the conduit, a plurality of insulating layers arranged between a conductive surface of the plurality of flow fields and the conduit, and a plurality of openings in the plurality of insulating layers providing a plurality of fluid connections between the conduit and the plurality of flow fields.

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

A proton exchange membrane (PEM) electrolyzer component selected from at least one of a bipolar plate or porous transport layer has an electrically conductive and oxidatively stable coating of an electrically conductive metal nitride or an electrically conductive metal oxide on at least one surface thereof.

A proton exchange membrane (PEM) electrolyzer component selected from at least one of a bipolar plate or porous transport layer has an electrically conductive and oxidatively stable coating of an electrically conductive metal nitride or an electrically conductive metal oxide on at least one surface thereof.

Self-cleaning electrochemical cells, systems including self-cleaning electrochemical cells, and methods of operating self-cleaning electrochemical cells are disclosed. The self-cleaning electrochemical cell can include a plurality of concentric electrodes disposed in a housing, a fluid channel defined between the concentric electrodes, and an electrical connector positioned at a distal end of a concentric electrode and electrically connected to the electrode. The electrical connectors may be configured to provide a substantially even current distribution to the concentric electrode and minimize a zone of reduced velocity occurring downstream from the electrical connector. The electrical connector may be configured to cause a temperature of an electrolyte solution to increase by less than about 0.5° C. while transmitting at least 100 W of power.

An alkaline water electrolysis system includes: a plurality of reaction chambers, each including a main electrode and an auxiliary electrode; a piston provided in each reaction chamber to change a volume of the reaction chamber through reciprocating motion; a drive motor; a connecting rod and a crankshaft installed to change rotational motion of the drive motor into reciprocating linear motion of the piston; a plurality of gas valves installed on an upper side of the reaction chamber to discharge hydrogen and oxygen generated in the reaction chamber through different paths, respectively; a pressure sensor installed in the reaction chamber; a controller configured to open and close the gas valves in response to a signal received from the pressure sensor; and an electrolyte supply apparatus provided to supply an electrolyte to the reaction chambers.

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.