Patent ID: 8266795

Claim:
A method of making an electrochemical gas sensor, the method comprising: selecting a self-supporting pre-form comprising a solid agglomerated continuous conductive material, the pre-form comprising a working electrode device region and a counter electrode device region and a reference electrode device region, wherein each device region comprises two pre-electrode regions in electrical communication spaced apart in a first direction and extending across the pre-form in a second direction; and forming a plurality of apertures in the self-supporting pre-form to provide a porous working electrode device region; and connecting the device regions by an electrolyte on the back side of the pre-form; and forming an insulating material comprising a polymeric material about each device region in a manner that the insulating material fills spacings defined in the first direction between the three electrode device regions; and forming one or more apertures in the insulating material at the working electrode in a manner to allow a gas to pass through to the working electrode; and severing electrical connection of the pre-form into discrete spaced apart working, counter, and reference electrodes carried by the insulating material to provide an electrode assembly; and enclosing the electrode assembly in a molded plastic enclosure in a manner that external electronic circuitry can be connected directly outside the enclosure, and protecting the front side of the enclosure by a gas permeable membrane to allow gases to pass into the enclosure for easy detection, while keeping out liquids, such as water, that could damage the electrode assembly, and protecting the backside of the enclosure that includes the electrolyte in chemical communication with each electrode with a gas impermeable cover.