Hydrogen concentration sensor

A method of assembling a hydrogen concentration sensor, the method comprising:

• situating a first end plate adjacent an hydrogen evolving electrode assembly to expose at least a portion of the hydrogen evolving electrode assembly through a first opening through a portion of the first end plate, the hydrogen evolving electrode assembly being configured to generate hydrogen based on exposure to a fluid at the first opening, the hydrogen evolving electrode assembly including first and second electrode layers that each include a coating on one side, the coating comprising a liquid electrolyte;
• situating at least one separator plate adjacent the hydrogen evolving electrode assembly on an opposite side of the hydrogen evolving electrode assembly from the first end plate, the at least one separator plate including a passage configured to allow a flow of hydrogen generated by the hydrogen evolving electrode assembly;
• situating a detection electrode assembly adjacent the at least one separator plate on an opposite side of the at least one separator plate from the hydrogen evolving electrode assembly to position at least a portion of the detection electrode assembly to be exposed to hydrogen in the passage, the detection electrode assembly including third and fourth electrode layers that each include a coating on one side, the coating comprising a liquid electrolyte;
• situating a second end plate adjacent the detection electrode assembly on an opposite side of the detection electrode assembly from the at least one separator plate to position a portion of the detection electrode assembly to be aligned with a second opening through a portion of the second end plate where the portion of the detection electrode assembly can be exposed to a fluid of interest through the second opening, the detection electrode assembly being configured to provide an indication of a concentration of hydrogen in the fluid of interest;
• positioning a heater near the electrode assemblies to increase a temperature of at least the liquid electrolyte;
• and
• securing the plates and the electrode assemblies in the situated positions.

A hydrogen concentration sensor, comprising:

• a first end plate including a first opening through a portion of the first end plate;
• a hydrogen evolving electrode assembly situated adjacent the first end plate with at least a portion of the hydrogen evolving electrode assembly exposed through the first opening, the hydrogen evolving electrode assembly being configured to generate hydrogen based on exposure to a fluid at the first opening;
• at least one separator plate adjacent the hydrogen evolving electrode assembly on an opposite side of the hydrogen evolving electrode assembly from the first end plate, the at least one separator plate including a passage configured to allow a flow of hydrogen generated by the hydrogen evolving electrode assembly;
• a detection electrode assembly situated adjacent the at least one separator plate on an opposite side of the at least one separator plate from the hydrogen evolving electrode assembly, at least a portion of the detection electrode assembly being exposed to hydrogen in the passage;
• and
• a second end plate adjacent the detection electrode assembly on an opposite side of the detection electrode assembly from the at least one separator plate, the second end plate including a second opening through a portion of the second end plate, a portion of the detection electrode assembly being exposed to a fluid of interest through the second opening, the detection electrode assembly being configured to provide an indication of a concentration of hydrogen in the fluid of interest,
• wherein:
• the hydrogen evolving electrode assembly includes two electrode layers and a matrix layer between the two electrode layers,
• the at least one isolating layer between the first end plate and the at least one separator plate includes three gaskets,
• one of the two electrode layers is situated in an opening in one of the three gaskets,
• the other of the two electrode layers is situated in an opening in another one of the three gasket, and
• the matrix layer is situated in a middle one of the three gaskets.