CN206270279U - The hydrogen gas sensor of wide-range - Google Patents

Abstract

The utility model discloses a kind of hydrogen gas sensor of wide-range, including housing, the gas detection cell that is arranged in the housing and waterproof and breathable gas barrier film, the gas barrier film is located at the side of the gas detection cell；It is provided with the housing and oxygen channel therein is entered with oxygen through the housing, the oxygen channel is located at side of the gas detection cell away from the gas barrier film.The hydrogen gas sensor of wide-range of the present utility model, suitable for the hydrogen content monitoring of the environment such as new-energy automobile in-car, being provided with oxygen channel carries out oxygen supply, ensure the supply of oxygen in course of reaction, and then the detection performance of guarantee sensor, coordinate gas barrier film etc. to realize that sensor has the hydrogen detection in concentration range wider.

Description

The hydrogen gas sensor of wide-range

Technical field

The utility model is related to a kind of hydrogen gas sensor, more particularly to a kind of hydrogen gas sensor of wide-range.

Background technology

With the progress and the improvement of people's living standards of society, automobile plays in the daily production and life of people More and more important role.Orthodox car is all using oil as power source, with CO, CO after oil combustion₂、NO、NO₂、SO₂、 Dust granules thing etc. is discharged into air as end-product.With the increase year by year of car ownership, the energy of countries in the world is endangered Machine and atmosphere pollution are increasingly severe, and atmosphere pollution 50% according to statistics is caused by the tail gas of motor vehicle emission.Although various countries All using restricting driving, collect a series of measure such as congestion expense to improve the atmosphere pollution caused by vehicle exhaust, but at all Solution still solves the problems, such as that motor vehicle emission could effect a radical cure atmosphere pollution in automobile in itself, only.So countries in the world are all New-energy automobile is being widelyd popularize, new-energy automobile refers to as power resources, comprehensive vehicle using unconventional vehicle fuel Dynamic Control and driving in terms of advanced technology, the know-why of formation is advanced, automobile with new technology, new construction.

Current new-energy automobile mainly includes fuel-cell vehicle and electric automobile.Fuel-cell vehicle is to be with pure hydrogen The energy, with reference to the power performance new-energy automobile that sets out of exploitation of fuel cell；It with battery is power row that electric automobile refers to That sails uses motor-driven automobile.All it is zero-emission although the operation principle of the two is different, is suitable for wideling popularize.Newly Energy automobile is different from orthodox car, the aspects such as power source, technology, emission is not only embodied in, in automobile manufacturing process There are some details to be noted that such as fuel-cell vehicle uses pure hydrogen as fuel, there is hydrogen container in the car, this is just to hydrogen storage The sealing of tank and pipeline proposes requirement, once it is hardly imaginable that leakage consequence occurs.Current electric automobile is generally used Lithium ion battery used as power source, decompose and can produce hydrogen, while making by lithium electricity inside battery material in overshoot or short circuit For the coolant of battery temperature management Main Means can also decompose generation hydrogen when charging voltage reaches certain grade.

Hydrogen is a kind of colourless, tasteless, nontoxic, inflammable and explosive gas, when the hydrogen content in air reaches 4% just Can explode.Due to colorless and odorless, flame is transparent to hydrogen during burning, therefore its presence is difficult to be found have by sense organ Titanic peril.So needing to install hydrogen monitoring unit on new-energy automobile, let out with reaching real-time online detection hydrogen Leakage or generation situation, are that safety of person vehicle escorts.

This special application scenarios with reference to automobile, it is desirable to which the hydrogen gas sensor for being used is monitored except satisfaction to Generally Recognized as safe Field is used outside the General Requirement of gas sensor, should also have range wider, both can accurately detect low concentration The purpose that hydrogen reaches getting up early early warning can ensure sensor when the gas for meeting or exceeding hydrogen explosion limit is touched still again So there is preferably detection performance.

Conventional hydrogen gas sensor has electric chemical formula hydrogen gas sensor, fuel cell formula hydrogen gas sensor, catalysis combustion at present Burning formula hydrogen gas sensor and semiconductor-type hydrogen gas sensor.There was only fuel cell formula in the hydrogen gas sensor of above-mentioned various principles Hydrogen gas sensor has a detection range wider, and the hydrogen gas sensor of remaining principle either can be with detectable concentration hydrogen or can be with Detection low-concentration hydrogen, it is impossible to accomplish that all there is preferably detection performance in whole concentration range.Catalytic combustion type sensor It is essentially identical with semiconductor-type sensors Cleaning Principle, although such sensor cost is primarily used for than relatively low Detection high concentrations of gas, it is impossible to the hydrogen of accurate detection below 2000PPM, it is impossible to accomplish getting up early early warning, loses redemption people's car The best opportunity of life；Electric chemical formula hydrogen gas sensor has relatively low Monitoring lower-cut and an ear detection precision higher, but nothing Method is applied to the detection of high concentration hydrogen, and in long-time contact high concentrations of gas, sensor decay is rapid and gradually loses Detection performance, cannot so confirm whether sensor can provide correct detection performance；Two come need frequently change pass Sensor.Although fuel cell formula hydrogen gas sensor is with detection range wider, because it uses micro-size fuel electricity Pond principle, the response time is very long, and its time required for reaching 80% transition has 10 minutes as long as, and peace cannot be applied to completely Full monitoring field.

Electrochemical sensor carries out gas detection using constant potentiometric electrolysis, by working electrode, to electrode, reference electrode and Electrolyte is constituted.Wherein working electrode is the place that under test gas chemically react；It is ground that oxygen reacts to electrode Side, and the closed-loop type of reaction is formed together with the reaction on working electrode；Reference electrode is used for providing the Zero Potential of stabilization, Preventing reaction of the testing result by cathodic polarization and oxygen on electrode is influenceed.Electrolyte provides proton transfer passage, Ensure that whole reaction can be smoothed out, be typically chosen the water-soluble of the acidic materials such as sulfuric acid, nitric acid, phosphoric acid, benzene sulfonic acid, benzoic acid Liquid serves as electrolyte.In order to accelerate under test gas reaction speed on the working electrode (s, generally potential point solution hair test gas is being determined Need to provide an electrode potential during body, this electrode potential is typically selected under test gas oxidation-reduction potential on the working electrode (s Place, to ensure quickly to trigger the reaction of under test gas.Due to being applied with external voltage, the noise of whole sensor to whole system Substantially increase.Because the noise of whole sensor improves, in order to keep accuracy of detection to be just correspondingly improved under test gas There is the electric signal of electrochemical reaction generation on the working electrode (s, the method commonly used in current industry is to increase under test gas to enter The amount of sensor internal reaches the purpose for improving detection performance with this.In order to ensure that gas as much as possible enters into sensor In, Conventional electrochemical sensor is generally communicated using porous gas barrier film come five ambient atmosphere environment, this resulted in except The moisture that reacting gas can be communicated in outer electrolyte by porous gas barrier film with atmospheric environment also can be with the shape of steam Formula carries out real-time exchange by the humidity in this layer of porous gas barrier film and environment.Oxygen is that whole chemical reaction is occurred Necessary factors, but exchanging for the moisture in reduction electrolyte as small as possible and external environment, and also to subtract The possibility that few liquid electrolyte is leaked from sensor, so Conventional electrochemical sensor is not additionally provided oxygen typically Service duct, but use and the public gas passage of reacting gas, but one does not have oxygen in the environment that detects if desired Sensor cannot just work；The two oxygen major parts to be entered into together in sensor with reaction gas is stopped by electrolyte, can Smoothly to reach few to the oxygen of electrode.Electrode is prepared using noble metal catalyst in electrochemical sensor in addition, Noble metal therein can be coated on electrode base material in the form of tiling, and there was only most table when reacting gas reaches working electrode The catalyst of layer can work, and the catalyst of internal layer cannot participate in reaction due to capped.Single-layer catalyst reactivity Limited, above-mentioned various reasons cause electrochemical sensor cannot generally be applied to the detection of high concentrations of gas, can be due to catalysis Agent activity is not enough and oxygen supply is not enough and cannot smoothly complete detection.

In sum, due to current hydrogen gas sensor there are problems that it is various, it is therefore desirable to exploitation is a kind of suitable Together in the sensor of new-energy automobile in-car hydrogen detection, meet and detection range wider is should also have outside use requirement.

Utility model content

The technical problems to be solved in the utility model is, there is provided a kind of hydrogen gas sensor of wide-range.

The utility model solves the technical scheme that its technical problem used：A kind of hydrogen sensing of high stability is provided Device, including housing, the gas detection cell that is arranged in the housing and waterproof and breathable gas barrier film, the gas every The side of the gas detection cell is located at from film；It is provided with the housing and oxygen therein is entered with oxygen through the housing Gas passage, the oxygen channel is located at side of the gas detection cell away from the gas barrier film.

Preferably, the gas detection cell includes electrolysis plastid and the electrode using solid supported noble metal catalyst, The electrode is including being arranged on the working electrode being electrolysed on plastid, to electrode and reference electrode；

The housing is provided with several contact pins, the working electrode, passes through lead and number respectively to electrode and reference electrode Individual contact pin is connected one by one.

Preferably, the working electrode is located at the electrolysis plastid towards on the side of the gas barrier film, described right Electrode and reference electrode are located on the relative opposite side of the electrolysis plastid.

Preferably, the working electrode, be porous gas diffusive electrode to electrode and reference electrode.

Preferably, the contact pin correspondence gas detection cell is arranged on the side of the housing.

Preferably, the contact pin is arranged on the bottom of the housing.

Preferably, the gas barrier film is poly tetrafluoroethylene, gathered fluoride film, polytetrafluoroethylene (PTFE)/hexafluoropropene Co-polymer membrane, the third vinyl ether copolymers of polytetrafluoroethylene (PTFE)/perfluor film, polyethylene/TFE copolymer film, polyimide film, One or more of combination in silicone rubber membrane and fluorination silicone rubber membrane.

Preferably, the hydrogen gas sensor also includes setting air admission hole on the housing, and the gas barrier film is in institute State and be covered in housing the air admission hole side.

The hydrogen gas sensor of wide-range of the present utility model, it is adaptable to the hydrogen content prison of the environment such as new-energy automobile in-car Survey, being provided with oxygen channel carries out oxygen supply, it is ensured that the supply of oxygen in course of reaction, and then ensure the detection of sensor Performance, coordinates gas barrier film etc. to realize that sensor has the hydrogen detection in concentration range wider.

Brief description of the drawings

Below in conjunction with drawings and Examples, the utility model is described in further detail, in accompanying drawing：

Fig. 1 is the cross-sectional view of the hydrogen gas sensor of the embodiment of the utility model one；

Fig. 2 be the embodiment of the utility model one hydrogen gas sensor in gas detection cell electrode catalyst microstructure Schematic diagram.

Fig. 3 is to survey the response time that hydrogen gas sensor of the present utility model is carried out when hydrogen is monitored with existing hydrogen gas sensor Examination curve map；

Fig. 4 is that hydrogen gas sensor of the present utility model tests response curve under different hydrogen concentration；

Fig. 5 is the lasting detection performance chart of hydrogen gas sensor of the present utility model and existing hydrogen gas sensor.

Specific embodiment

In order to be more clearly understood to technical characteristic of the present utility model, purpose and effect, accompanying drawing is now compareed detailed Illustrate specific embodiment of the present utility model.

As shown in figure 1, the hydrogen gas sensor of the embodiment of the utility model one, including housing 10, it is arranged in housing 10 The gas barrier film 30 of gas detection cell 20 and waterproof and breathable；The gas barrier film 30 of waterproof and breathable is located at gas and detects single First 20 sides, to being filtered by gas, and waterproof.The oxygen channel 11 through housing 10 is provided with housing 10, oxygen leads to Cross the oxygen channel 11 and enter housing 10 as supply.Oxygen channel 11 is located at gas detection cell 20 away from gas barrier film 30 Side.

Wherein, housing 10 plays the ballistic support effect of whole sensor, and internal with chamber supplied gas detection unit 20th, gas barrier film 30 etc. is accommodating wherein.(bottom as shown in Figure 1) is provided with several contact pins, contact pin and gas on housing 10 Detection unit 20 is connected, and is additionally operable to be connected with extraneous pcb board, is in real time sent the electric signal that gas detection cell 20 is produced to outer Boundary's pcb board.Oxygen channel 11 is preferably through the side of the housing 10 where contact pin.

The material of housing 10 can be the high molecular polymer that PP, PC, ABS, nylon etc. have some strength and toughness, anti-impact Hit and vibration resistance is strong, and be preferably applied to the material of acidic electrolyte bath.

The setting of oxygen channel 11 in housing 10, it is ensured that the supply of oxygen in course of reaction, and then ensure sensor Detection performance.Opening of the oxygen channel 11 on housing 10 is provided with gas barrier film (not shown)；Oxygen channel 11 passes through Gas barrier film is communicated with atmospheric environment, and the gas barrier film for being used can ensure that gas molecule passes through at ambient pressure, but Liquid and dust cannot pass through, and the material of gas barrier film used can be polytetrafluoroethylene (PTFE) (PTFE), gather PVF (PVDF), polytetrafluoroethylene (PTFE)/hexafluoropropylene copolymer (PFEP), the vinyl ether copolymers of polytetrafluoroethylene (PTFE)/perfluor third (PFA), poly- One kind in Tefzel (PETFE), polyimides (PI), silicon rubber (SR) or fluorination silicon rubber (FSR) or Various combinations.

The 20 pairs of gas by gas barrier film 30 of gas detection cell is detected.

Again as shown in figure 1, gas detection cell 20 includes electrolysis plastid 21, the electricity using solid supported noble metal catalyst Pole, electrode is including being arranged on the working electrode 22 being electrolysed on plastid 21, to electrode 23 and reference electrode 24.Wherein working electrode 22nd, to electrode 23, reference electrode 24 respectively with electrolysis the good contact of plastid 21, to ensure the patency of mass transfer.Working electrode 22, Can be same porous gas diffusive electrode, or different porous gas diffusion electricity to electrode 23 and reference electrode 24 Pole.Active component in each electrode, can be same solid supported noble metal catalyst, or different loaded your gold Metal catalyst；Catalyst is the one kind or several in golden (Au), rhodium (Rh), platinum (Pt), ruthenium (Ru), palladium (Pd), iridium (Ir), silver-colored (Ag) The mixture of metal is planted, preferred pair hydrogen has the catalyst of selective active, and its microstructure can be as shown in Figure 2.It is loaded Noble metal catalyst can be supported in above-mentioned metal or metal mixture on conductive carbon particle, and conductive carbon particle therein can Being the combination of one or more in carbon black, CNT or activated carbon.

The conductive carbon particle for serving as catalyst carrier has specific surface area and porosity higher higher, by accurate choosing The nano-scale of the noble metal granule that the aperture in carbon particle and precise control are generated is selected to ensure that noble metal granule can be with Preferably it is attached in the aperture of carbon particle.The carbon particle of noble metal is attached with into irregular polygon, when being made electrode Catalytic inner can form more space, further increase the probability of the catalyst that hydrogen can be released, and can receive More reaction gas chemically reacts herein.

Electrolysis plastid 21 plays a part of to transmit proton, can be liquid electrolyte, semi-solid electrolyte or solid electrolytic Matter, wherein the active component of transmission proton can be sulfuric acid, nitric acid, phosphoric acid, benzene sulfonic acid, benzoic acid etc..Gas detection cell 20 Also include a shell with accommodating electrolysis plastid 21.In the hydrogen gas sensor, using constant potentiometric electrolysis in real time by the hydrogen in environment Gas content is converted into the electric signal that can be detected, realizes the detection of hydrogen.

Preferably, response speed is accelerated to shorten mass transfer distance with the contact mode that tiles between each electrode and electrolysis plastid 21 Degree.Further, working electrode 22 is located at electrolysis plastid 21 towards on the side of gas barrier film 30 so that from gas barrier film 30 object gas for coming directly reach working electrode 22 and selective chemical reaction occur；To electrode 23 and reference electrode 24 In on the relative opposite side of electrolysis plastid 21.Oxygen in environment chemically reacts on to electrode 23, with working electrode 22 On chemical reaction form the closed loop of reaction together, it is ensured that the continuation of chemical reaction；Reference electrode 24 is used to provide stabilization Zero Potential, prevent output signal from being influenceed by the chemical reaction on electrode and drift, it is ensured that the stability of output.

Working electrode 22, electrode 23 and reference electrode 24 are connected one by one by lead with several contact pins respectively.Wherein, such as Shown in Fig. 1, working electrode 22 is connected by lead 221 with contact pin 101, and electrode 23 is connected by lead 231 with contact pin 102, Reference electrode 24 is connected by lead 241 with contact pin 103, realizes the propagation of electric signal.

Gas barrier film 30 is closely knit non-porous, with water-proof breathable properties.Gas molecule is needed by absorption-dissolving-desorption Program is entered into sensor through film, so significantly limit the quantity of the gas molecule that can enter sensor internal, Such that it is able to regulate and control to actually enter the gas molecule quantity of sensor internal.Hydrone either liquid form or gas shape Formula cannot all pass through this tunic, so as to completely cut off the exchange of sensor internal humidity or moisture and external environment.

Alternatively, gas barrier film 30 can be polytetrafluoroethylene (PTFE) (PTFE) film, gather PVF (PVDF) film, poly- four PVF/hexafluoropropylene copolymer (PFEP) film, polytetrafluoroethylene (PTFE)/perfluor third vinyl ether copolymers (PFA) film, polyethylene/tetra- One kind in fluoride copolymers (PETFE) film, polyimides (PI) film, silicon rubber (SR) film and fluorination silicon rubber (FSR) film Or various combinations.,

In addition, the hydrogen gas sensor also includes setting air admission hole 12 on the housing 10, gas barrier film 30 is in housing 10 Inside it is covered in the side of air admission hole 12.By taking Fig. 1 sensor placement directions as an example, air admission hole 12 is located at the top of housing 10, for be measured Gas enters, and oxygen channel 11 is located at the inner bottom part of housing 10, enters in housing 10 for oxygen in environment.Hydrogen is pushed up from housing 10 After portion enters, by gas barrier film 30, enter wherein from the top of gas detection cell 20；Can be from gas as the oxygen of supply The bottom of detection unit 20 enters wherein.

Hydrogen gas sensor of the present utility model is monitored the hydrogen of concentration 1% as test, with British city technology company type Number for 7HYT hydrogen gas sensor as a comparison, the response time test curve map as shown in Figure 3, wherein curve A1 be this reality With the response curve of new hydrogen gas sensor, curve B1 is the response curve for contrasting hydrogen gas sensor.

From figure knowable to curve, hydrogen gas sensor of the present utility model T90 when 1% hydrogen is tested is 14 seconds, and English The hydrogen gas sensor T90 of city technology company of state model 7HYT is 93 seconds, it is known that hydrogen gas sensor response of the present utility model Rapidly, the hydrogen sensitivity to low content is high, and detection range is wide.

Hydrogen gas sensor of the present utility model is tested under different hydrogen concentration, its response curve is as shown in Figure 4. As can be seen from the figure sensor has good linear response in the range of the hydrogen of 0.02-18%, and coefficient correlation reaches 0.9997。

Fig. 5 is lasting detection performance of the hydrogen gas sensor of the present utility model when density of hydrogen is 18%, its center line A2 Represent hydrogen gas sensor of the present utility model, line B2 represents the hydrogen gas sensor of British city technology company model 7HYT.By As can be seen that hydrogen gas sensor exports more stable always in the experimentation of two weeks by a definite date in figure, and English as a comparison The hydrogen gas sensor of city technology company of state model 7HYT has occurred as soon as decay after experiment starts 5 minutes, during by 31 minutes Decay is complete, and output signal returns to value during without hydrogen.

Embodiment of the present utility model is the foregoing is only, the scope of the claims of the present utility model is not thereby limited, it is every The equivalent structure or equivalent flow conversion made using the utility model specification and accompanying drawing content, or be directly or indirectly used in Other related technical fields, are similarly included in scope of patent protection of the present utility model.

Claims (8)

1. a kind of hydrogen gas sensor of wide-range, it is characterised in that including housing（10）, be arranged on the housing（10）Interior gas Body detection unit（20）And the gas barrier film of waterproof and breathable（30）, the gas barrier film（30）Positioned at gas detection Unit（20）Side；The housing（10）Inside it is provided with through the housing（10）Oxygen channel therein is entered with oxygen （11）, the oxygen channel（11）Positioned at the gas detection cell（20）Away from the gas barrier film（30）Side.

2. hydrogen gas sensor according to claim 1, it is characterised in that the gas detection cell（20）Including electrolyte Body（21）And using the electrode of solid supported noble metal catalyst, the electrode includes being arranged on the electrolysis plastid（21）On Working electrode（22）, to electrode（23）And reference electrode（24）；

The housing（10）It is provided with several contact pins, the working electrode（22）, to electrode（23）And reference electrode（24）Respectively It is connected one by one with several contact pins by lead.

3. hydrogen gas sensor according to claim 2, it is characterised in that the working electrode（22）Positioned at the electrolyte Body（21）Towards the gas barrier film（30）Side on, it is described to electrode（23）And reference electrode（24）Positioned at the electrolysis Plastid（21）Relative opposite side on.

4. hydrogen gas sensor according to claim 2, it is characterised in that the working electrode（22）, to electrode（23）With Reference electrode（24）It is porous gas diffusive electrode.

5. hydrogen gas sensor according to claim 2, it is characterised in that the contact pin correspondence gas detection cell （20）It is arranged on the housing（10）Side on.

6. hydrogen gas sensor according to claim 5, it is characterised in that the contact pin is arranged on the housing（10）Bottom Portion.

7. the hydrogen gas sensor according to claim any one of 1-6, it is characterised in that the gas barrier film（30）It is poly- Tetrafluoroethylene, gathered fluoride film, polytetrafluoroethylene (PTFE)/hexafluoropropylene copolymer film, the vinethene of polytetrafluoroethylene (PTFE)/perfluor third Co-polymer membrane, polyethylene/TFE copolymer film, polyimide film, silicone rubber membrane and fluorination silicone rubber membrane in one kind or Various combinations.

8. the hydrogen gas sensor according to claim any one of 1-6, it is characterised in that the hydrogen gas sensor also includes setting In the housing（10）On air admission hole（12）, the gas barrier film（30）In the housing（10）Inside it is covered in the air inlet Hole（12）Side.