Novel electrochemical gas sensor

Abstract

The utility model relates to a novel electrochemical gas sensor which comprises a bottom plate and a sensor main body arranged on the bottom plate, the sensor main body comprises a shell which is provided with an inner cavity and is provided with a gas hole in the top, and a dustproof and waterproof film covers the gas hole. The diffusion sheet, the electrode unit, the adsorption cotton and the supporting plate are sequentially arranged in an inner cavity of the shell from top to bottom, the electrode unit comprises a working electrode, a counter electrode, a reference electrode and a separation membrane, the working electrode is located above the separation membrane, the counter electrode and the reference electrode are located below the separation membrane, the supporting plate is provided with a containing groove with a downward opening, and the adsorption cotton is arranged in the containing groove. An accommodating groove is formed in the bottom plate, the accommodating groove is used for accommodating electrolyte, the top surface of the supporting plate is arranged above the accommodating groove, a plurality of leakage holes are formed in the top surface of the supporting plate, and pins are arranged on the bottom plate and are connected with the electrode units through leads. The gas sensor is suitable for electrochemical gas sensors of hydrogen, carbon monoxide, hydrogen sulfide and the like, and is simple in structure, convenient and convenient for batch production.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a novel electrochemical gas sensor. Background Art

[0002] Hydrogen (H2) has a low molecular mass and density. It is a colorless, odorless, flammable gas that is insoluble in water under normal pressure. When the H2 concentration is between 4.1% and 74.8%, it can cause an explosion when encountering an open flame. Therefore, hydrogen is very dangerous. For the safety of humans and society, it is necessary to monitor H2. Currently, hydrogen sensors using electrochemical principle, semiconductor principle, and catalytic combustion principle are widely used. Among them, the electrochemical hydrogen sensor is widely used due to its advantages such as high sensitivity, small size, easy to carry, and low price. The problems existing in the existing electrochemical gas sensors are as follows:

[0003] The electrochemical H2 sensors provided in patents CN 113030221 A, CN 113671008 A, CN 211148510 U, etc. have a cylindrical or irregular size structure, and the size is relatively large, which is limited in use in fields such as vehicle-mounted and civilian; the pins are long and exposed, which are easily damaged by falling or bumping; the current electrochemical H2 sensors are vulnerable to high-concentration gas impact, resulting in current fluctuations or even failure, and have certain technical defects. Summary of the Utility Model

[0004] In view of the deficiencies of the existing technology, the utility model provides a novel electrochemical gas sensor suitable for hydrogen, simple, convenient, and easy to mass-produce.

[0005] To achieve the above object, the utility model provides a medium and low temperature cold water system, and has the following technical solutions: The sensor includes a bottom plate and a sensor main body disposed on the bottom plate. The sensor main body includes a housing having an inner cavity and a gas hole provided at the top. The gas hole is covered with a dust and waterproof film. The inner cavity of the housing is sequentially provided with a diffusion sheet, an electrode unit, an adsorption cotton, and a support plate from top to bottom. The electrode unit includes a working electrode, a counter electrode, a reference electrode, and a separation membrane. The working electrode is located above the separation membrane, and the counter electrode and the reference electrode are located below the separation membrane. The support plate has a receiving groove with an opening facing downwards, and the receiving groove is used to accommodate the electrolyte. Above the receiving groove is the top surface of the support plate, and several leakage holes are provided on the top surface of the support plate. Pins are provided on the bottom plate, and the pins are connected to the electrode unit through leads.

[0006] Preferably, the area of the working electrode is set to be larger than the area of the counter electrode, and the area of the counter electrode is set to be larger than the area of the reference electrode.

[0007] Preferably, the working electrode is connected to the pin of the working electrode through the lead of the working electrode, the counter electrode is connected to the pin of the counter electrode through the lead of the counter electrode, the lead of the reference electrode is connected to the pin of the reference electrode, and the leads of the working electrode, the counter electrode, and the reference electrode pass through the gap between the support plate and the inner wall of the housing.

[0008] Preferably, the pin is a contact type, plug-in type or welding type pin, and the pin is located at the bottom or side of the bottom plate.

[0009] Preferably, the thickness of the separation membrane is 100 - 300 μm.

[0010] Preferably, the diffusion sheet is a diffusion sheet with a waterproof function.

[0011] Preferably, the bottom plate is a square bottom plate, the sensor body is a circular or square body, the entire sensor body is disposed on the bottom plate, and the area of the bottom plate is larger than the bottom area of the sensor body.

[0012] Preferably, the diameter of the sensor body is 3 - 15 mm, and the length of the long side of the bottom plate is 5 - 15 mm.

[0013] Preferably, the top of the support plate is a plane.

[0014] Preferably, the diffusion sheet, the electrode unit, the adsorption cotton, and the support plate are stacked and assembled layer by layer.

[0015] The novel electrochemical gas sensor of the present invention can significantly reduce the volume of the sensor. Especially for the hydrogen sensor, it has a simple and lightweight structure, which is convenient for use in more fields; it can reduce the impact of external air pressure or external high-concentration gas, and can protect the inside of the hydrogen sensor from damage; the bottom plate is larger than the sensor body, and the pins are inside the structural parts, which can reduce the damage of the hydrogen sensor caused by dropping to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments.

[0017] Figure 1 It is a schematic diagram of the external structure of the first embodiment of the novel electrochemical gas sensor of the present invention.

[0018] Figure 2 It is a schematic diagram of the structure on the back of the pin of the first embodiment of the novel electrochemical gas sensor of the present invention.

[0019] Figure 3It is a central cross-sectional view of the first embodiment of the novel electrochemical gas sensor of the present utility model.

[0020] Figure 4 This is a schematic diagram of the appearance structure of the support plate in the first embodiment of the novel electrochemical gas sensor of the utility model.

[0021] Figure 5 This is a schematic structural diagram of a second embodiment of the novel electrochemical gas sensor of the utility model, wherein the pins are arranged on the side of the base plate. DETAILED DESCRIPTION

[0022] In order to more clearly describe the technical content of the present invention, it is further described below in conjunction with specific embodiments.

[0023] In order to reduce the size of electrochemical sensors, expand their application range, make up for the design defects of existing electrochemical sensors, prevent sensors from being damaged or failing due to the impact of high-concentration gases, and reduce the risk of falling damage, such as Figures 1 to 4 As shown, it is the first embodiment of the new electrochemical gas sensor of the utility model, especially the electrochemical hydrogen sensor. The structure is small in size, simple and lightweight, and is easy to use in more fields. It is also suitable for use in a series of gas sensors such as electrochemical CO, electrochemical SO2, electrochemical H2S, electrochemical NO, etc., with two electrodes and three electrodes. Among them, the sensor includes a base plate 1 and a sensor body 2 arranged on the base plate 1. The base plate 1 and the sensor body 2 can be a whole or a combination of two parts separately, and can be made of ABS resin, PP resin, PA resin and other materials.

[0024] like Figure 3 As shown, the sensor body 2 includes a shell with an inner cavity and an air hole 2-9 on the top. The air hole 2-9 is covered with a dustproof and waterproof film 3 to protect the sensor. The inner cavity of the shell is provided with a diffusion sheet 2-8, an electrode unit, adsorbent cotton 2-3, and a support plate 2-1 from top to bottom. The diffusion sheet 2-8, the electrode unit, adsorbent cotton 2-3, and the support plate 2-1 are stacked and assembled layer by layer without obvious gaps in the middle to prevent shaking and deflection. The diffusion sheet 2-8 is a diffusion sheet with waterproof function and can also have the basic performance of buffering diffusion. It can be a combination of one or more materials such as waterproof carbon paper, waterproof carbon cloth, and waterproof breathable membrane to prevent damage to the sensor due to high test gas concentration or excessive air pressure.

[0025] The described electrode unit includes a working electrode 2-5, a counter electrode 2-6, a reference electrode 2-7, and a separator membrane 2-4. The working electrode 2-5 is located above the separator membrane 2-4, and the counter electrode 2-6 and the reference electrode 2-7 are located below the separator membrane 2-4. The thickness of the separator membrane 2-4 is 100 - 300 μm, and the material can be one or a combination of Nafion, filter paper, ceramic membrane, PTFE, PVDF, PP breathable membrane, etc., and has wettability, ion exchange, and gas permeability properties, etc. The working electrode 2-5, the counter electrode 2-6, and the reference electrode 2-7 can be on the same separator membrane 2-4, greatly saving the internal space of the sensor, or can be separately prepared on independent separator membranes 2-4, that is, the separator membrane 2-4 in this embodiment can be an integral membrane or an independent membrane.

[0026] The adsorption cotton 2-3 can store and adsorb the acidic electrolyte outside the support plate 2-1 and transport the electrolyte to the separator membrane 2-4, the working electrode 2-5, the counter electrode 2-6, and the reference electrode 2-7.

[0027] Among them, the area of the working electrode 2-5 is set to be larger than the area of the counter electrode 2-6, and the area of the counter electrode 2-6 is set to be larger than the area of the reference electrode 2-7. The working electrode 2-5, the counter electrode 2-6, and the reference electrode 2-7 can mainly be composed of one or a combination of metals such as Pt, Au, Ba, Ga, Fe, Ni, Ti, Sn, Ta, Ag, etc., and are supported on one of the carbon skeletons such as graphene, graphene oxide, carbon powder, activated carbon, etc., and are bonded using one or a combination of PTFE, PVDF, PP, PA, PVP, etc., and then electrode preparation is carried out using processes such as spraying, screen printing, roll pressing, hot pressing, etc.

[0028] The support plate 2-1 has a receiving groove with an opening facing downwards. The receiving groove is used to accommodate the electrolyte 2-10. Above the receiving groove is the top surface of the support plate. The top surface of the support plate 2-1 is provided with several leakage holes 2-1A for the adsorption and leakage of the electrolyte. The top of the support plate is preferably a flat surface, which can assist in stabilizing the internal components of the sensor.

[0029] Pins 4 are provided on the bottom plate 1. The pins 4 are connected to the electrode unit through leads 2-2. Specifically, the working electrode is connected to the pin of the working electrode through the lead of the working electrode, the counter electrode is connected to the pin of the counter electrode through the lead of the counter electrode, and the lead of the reference electrode is connected to the pin of the reference electrode, as Figure 3 shown, the leads of the working electrode, the counter electrode, and the reference electrode pass through the gap between the support plate 2-1 and the inner wall of the housing.

[0030] The described pin 4 can be a contact type, pluggable or soldered pin. The leads 2-2 and the pin 4 can be one or more of Cu, Pt, Au, Ni, Ta, Ta, Fe, Sn and other alloy or plated metal products, having a certain degree of bendability and flexibility. In the first embodiment of the present invention, the pin is located at the bottom of the bottom plate 1, that is, the pin 4 penetrates through the bottom plate and exposes from the bottom of the bottom plate. The pin is inside the structural member, which can reduce the damage of the sensor due to dropping to a certain extent. As Figure 5 shown in the second embodiment, the pin 4 is located on the side of the bottom plate 1. The length of the pin is flexible, which is convenient for use in different fields and different scenarios.

[0031] As Figure 1 shown, the bottom plate 1 is a square bottom plate, the sensor body 2 is a circular body, the entire sensor body 2 is arranged on the bottom plate 1, and the area of the bottom plate 1 is larger than the bottom area of the sensor body 2, which can increase the buffering effect during the dropping process to a certain extent, thereby reducing the risk of dropping damage. Among them, the diameter of the sensor body is 3-15 mm, and the length of the long side of the bottom plate is 5-15 mm.

[0032] The novel electrochemical gas sensor of the present invention can greatly reduce the volume of the sensor, especially the hydrogen sensor. The structure is simple and light, which is convenient for use in more fields; it can reduce the impact of external air pressure or external high-concentration gas, and can protect the inside of the hydrogen sensor from damage; the bottom plate is larger than the sensor body, and the pins are inside the structural member, which can reduce the damage of the hydrogen sensor due to dropping to a certain extent.

[0033] In this specification, the present invention has been described with reference to its specific embodiments. However, it is obvious that various modifications and transformations can still be made without departing from the spirit and scope of the present invention. Therefore, the specification and drawings should be regarded as illustrative rather than restrictive.

Claims

1. A novel electrochemical gas sensor, characterized in that: The sensor includes a base plate and a sensor body arranged on the base plate, the sensor body includes a shell having an inner cavity and an air hole on the top, the air hole is covered with a dustproof and waterproof film, the inner cavity of the shell is provided with a diffusion sheet, an electrode unit, adsorption cotton, and a support plate from top to bottom, the electrode unit includes a working electrode, a counter electrode, a reference electrode, and a separator, the working electrode is located above the separator, the counter electrode and the reference electrode are located below the separator, the support plate has a accommodating groove with an opening facing downward, the accommodating groove is used to accommodate electrolyte, the top of the accommodating groove is the top surface of the support plate, the top surface of the support plate is provided with several leakage holes, pins are arranged on the base plate, and the pins are connected to the electrode unit through leads.

2. The novel electrochemical gas sensor according to claim 1 is characterized in that: The area of ​​the working electrode is set to be larger than the area of ​​the counter electrode, and the area of ​​the counter electrode is set to be larger than the area of ​​the reference electrode.

3. The novel electrochemical gas sensor according to claim 1 is characterized in that: The working electrode is connected to the pin of the working electrode through the lead of the working electrode, the counter electrode is connected to the pin of the counter electrode through the lead of the counter electrode, the lead of the reference electrode is connected to the pin of the reference electrode, and the lead of the working electrode, the lead of the counter electrode, and the lead of the reference electrode pass through the gap between the support plate and the inner wall of the shell.

4. The novel electrochemical gas sensor according to claim 1 is characterized in that: The pins are contact type, plug-in type or welding type pins, and the pins are located at the bottom or side of the base plate.

5. The novel electrochemical gas sensor according to claim 1 is characterized in that: The thickness of the separation membrane is 100-300 μm.

6. The novel electrochemical gas sensor according to claim 1 is characterized in that: The diffusion sheet is a diffusion sheet with waterproof function.

7. The novel electrochemical gas sensor according to claim 1 is characterized in that: The bottom plate is a square bottom plate, the sensor body is a round or square body, the sensor body is entirely arranged on the bottom plate, and the area of ​​the bottom plate is larger than the bottom area of ​​the sensor body.

8. The novel electrochemical gas sensor according to claim 7 is characterized in that: The diameter of the sensor body is 3-15 mm, and the length of the long side of the bottom plate is 5-15 mm.

9. The novel electrochemical gas sensor according to claim 1 is characterized in that: The top of the support plate is a plane.

10. The novel electrochemical gas sensor according to claim 1, characterized in that: The diffusion sheet, electrode unit, adsorption cotton and support plate are assembled layer by layer.

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