Abstract: Various embodiments disclose an electronic circuit for an electrochemical gas sensor. The electronic circuit comprises a first switching element electrically coupled to a reference terminal of the electrochemical gas sensor and a ground voltage terminal. Further, the electronic circuit comprises a second switching element electrically coupled to a sensing terminal of the electrochemical gas sensor and the ground voltage terminal. In an instance in which the electrochemical gas sensor is powered OFF, the first switching element and the second switching element are configured to electrically couple the reference terminal and the sensing terminal to the ground voltage terminal such that current generated when the sensing electrode and the target gas react while the electrochemical gas sensor is powered OFF flows to the ground voltage terminal and the potential of the reference terminal and the sensing terminal remain the equal.

Abstract: A method and apparatus are provided to determine the composition of one or more gases. In the context of a method, a sensory assembly and at least one processor, the sensor assembly comprising a first gas sensor and a second gas sensor, includes causing the first sensor to be powered to detect a presence of one or more gas while the second sensor is unpowered. The method further includes detecting the presence of one or more gases while the second sensor is unpowered. in response to detecting the presence of the one or more gases, the method includes causing the second sensor to be powered. The method still further includes capturing sensor data corresponding to at least one of the one or more gases. The method also includes identifying the at least one of the one or more gases based on an analysis of the sensor data.

Abstract: Provided is a gas sensor and methods of monitoring the same. The gas sensor may detect gas restrictions within the gas sensor. The gas sensor may include a test gas diffusion path allowing for monitoring of restrictions within the gas sensor. A pulse of test gas may be electrochemically generated into a void disposed between the membrane and capillary of the gas sensor. The resulting transient signal on the sensing electrode may be analyzed to determine the degree of restriction present in the gas sensor.

Abstract: Embodiments relate generally to systems and methods for identifying the concentration of an electrolyte. A method may comprise scanning a diagnostic micro-electrode of an electrochemical sensor using scanning voltammetry at a plurality of electrolyte concentrations; generating a variable set of readings from the first scanning voltammetry scan using a potential difference between a strong hydrogen adsorption peak and an oxide reduction peak and/or oxide formation peak at each of the plurality of electrolyte concentrations; and determining a correlation by plotting the variable set of readings and the plurality of electrolyte concentrations.

Abstract: Apparatus and associated methods relate to a micro-electro-mechanical system (MEMS) based gas sensor including an electrolyte contacting one or more top electrode(s) arranged on the bottom surface of a top semiconductor substrate (TSS), and one or more bottom electrode(s) arranged on the top of a bottom semiconductor substrate (BSS), the TSS and BSS joined with an adhesive seal around the electrolyte, the sensor including one or more capillaries providing gaseous communication to the electrolyte from an external ambient environment. The electrodes may be electrically accessed by one or more vias to externally accessible bond pads. In some examples, an electrical connection may be made from an additional bond pad on top of the TSS to the electrolyte. Various embodiments may reduce the size of various gas sensors to advantageously allow their inclusion into portable electronic devices.

Abstract: Embodiments relate generally to systems, devices, and methods for depositing an electrode and an electrolyte on a microelectromechanical system (MEMS) electrochemical sensor. A method may comprise providing a blade on a surface of a substrate; providing a ridge along the perimeter of the substrate; pressing the electrode and the electrolyte onto the blade and the ridge; cutting the electrode into multiple electrodes; positioning the electrolyte to contact the surface, the blade, and the ridge; and positioning the multiple electrodes to contact the surface, the blade, and the ridge.

Abstract: An electrochemical sensor comprises a substrate disposed within a housing, a plurality of electrodes disposed on a first surface of the substrate, an electrolyte disposed over at least a portion of each electrode of the plurality of electrodes, and a capillary disposed through the substrate. The capillary is configured to provide a diffusion pathway for a target gas to pass from an exterior of the housing to one or more of the plurality of electrodes.

Abstract: A gas sensor including a gas sensing electrode, a counter electrode disposed within a housing, and respective conductors that connect the gas sensing electrode to the counter electrode via a sensing circuit is disclosed. The housing includes a solid electrolyte in communication with the gas sensing electrode and counter electrode wherein the solid electrolyte further comprises one or more coatings or layers. The one or more coatings or layers have a lower water vapor transport rate than that of the electrolyte, such that, in use, water vapor transport between the electrolyte and atmosphere is reduced.

Abstract: Apparatus and associated methods relate to a compact gas sensor (CGS) including a housing with a central stepped cavity with one or more first lead contact(s) forming a portion of a base plane in a bottom of the cavity and one or more second lead contact(s) forming a portion of a stepped plane higher than the base plane, the cavity sized to receive a chemically based stack of material made up of a bottom diffusion electrode layer, a middle electrolyte gel layer, and a top diffusion electrode layer. The bottom diffusion electrode layer is in electrical contact with the first lead contact(s). The top diffusion electrode layer electrically couples to the second lead contact(s) via an overlaying micro electromechanical system (MEMS) element layer with conductive coating. In an illustrative example, the CGS may provide gas sensing in small spaces.

Abstract: An electrochemical sensor includes a ceramic substrate, a capillary disposed through the ceramic substrate, a plurality of electrodes disposed on a first surface of the ceramic substrate, an electrolyte disposed over at least a portion of each electrode of the plurality of electrodes, a coating disposed over the plurality of electrodes and the electrolyte, and control and detection circuitry coupled to the substrate. The coating sealingly couples to the substrate over the plurality of electrodes and the electrolyte, and the plurality of electrodes are electrically coupled to the control and detection circuitry.

Abstract: Systems and methods of fast power up for electrochemical sensors are provided. A system can include an electrochemical sensor, and a potentiostat circuit, wherein, upon startup, the potentiostat circuit drives the electrochemical sensor to the electrochemical sensor's normal operating condition at a rate that is not limited by voltage and/or current supply. A method can include a potentiostat circuit driving an electrochemical sensor to the electrochemical sensor's normal operating condition at a rate that is not limited by voltage and/or current supply.

Abstract: An electrochemical gas sensor having an electrode with a catalyst distributed on a porous surface is described. The porous surface can be a polytetrafluoroethylene tape. Alternate embodiments include layered or stacked electrodes.

Abstract: Embodiments of the disclosure include an electrochemical sensor comprising a housing defining an interior space; a sensing electrode; a counter electrode; and an electrical contact; wherein at least one of the sensing electrode or the counter electrode comprises a contact portion, wherein the contact portion is biased into contact with and electrically coupled to the electrical contact, and wherein a compression on the contact portion is different from a compression on the remaining body of the electrode.

Abstract: A gas sensor includes know types of electrodes such has sensing electrodes, counter electrodes or reference electrodes to sense the presence of a predetermined gas. In addition, at least one diagnostic electrode is carried in the sensor. The diagnostic electrode implements at least one diagnostic function without substantially impairing the gas sensing function. The diagnostic electrode is immersed in sensor electrolyte.

Abstract: A gas sensor includes known types of electrodes such as sensing electrodes, counter electrodes or reference electrodes to sense the presence of a predetermined gas. In addition, at least one diagnostic electrode is carried in the sensor. The diagnostic electrode implements at least one diagnostic function without substantially impairing the gas sensing function. The diagnostic electrode is immersed in sensor electrolyte.

Abstract: An electrochemical detector can be powered partly, or entirely by voltages generated by the sensor. Using either active circuits or a passive component which produces a predetermined voltage drop in the respective sensor, two electrode consumable anode oxygen sensors can be provided which do not evolve hydrogen during operation.

Abstract: An electrochemical gas sensor includes additional gas diffusion electrodes incorporated to carry out one or more diagnostic functions while the sensor is responding to a target gas. Members of a plurality of sensing and diagnostic electrodes can be switched by associated control circuits to intermittently sense a target gas while others intermittently sense a different gas. The diagnostic electrodes are in direct communication with the target gas that is entering the cell.

Abstract: A gas sensor including a gas sensing electrode, a counter electrode disposed within a housing, and respective conductors that connect the gas sensing electrode to the counter electrode via a sensing circuit is disclosed. The housing includes a solid electrolyte in communication with the gas sensing electrode and counter electrode wherein the solid electrolyte further comprises one or more coatings or layers. The one or more coatings or layers have a lower water vapor transport rate than that of the electrolyte, such that, in use, water vapor transport between the electrolyte and atmosphere is reduced.

Abstract: A method of improving performance of electrochemical gas sensors includes cycling potentials applied to one or more of the electrodes of the respective sensor(s) to improve performance of a different electrode. In a process for treating a reference electrode, potentials can be applied to working and, or counter electrodes so as to modify the environment in the vicinity of the reference electrode. An apparatus can carry out the method automatically.

Abstract: An electrochemical detector can be powered partly, or entirely by voltages generated by the sensor. Using either active circuits or a passive component which produces a predetermined voltage drop in the respective sensor, two electrode consumable anode oxygen sensors can be provided which do not evolve hydrogen during operation.