CN112325913A - Fiber grating hydrogen sensing system and sensor based on amorphous palladium-based alloy - Google Patents
Fiber grating hydrogen sensing system and sensor based on amorphous palladium-based alloy Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
- G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
- G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
- G01D5/35306—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using an interferometer arrangement
- G01D5/35309—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using an interferometer arrangement using multiple waves interferometer
- G01D5/35316—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using an interferometer arrangement using multiple waves interferometer using a Bragg gratings
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D21/00—Measuring or testing not otherwise provided for
- G01D21/02—Measuring two or more variables by means not covered by a single other subclass
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
Abstract
The invention discloses a fiber grating hydrogen sensing system based on amorphous palladium-based alloy. The hydrogen sensing system is formed by serially connecting and welding a first fiber grating and a second fiber grating with different central wavelengths, a sensing film layer is coated on the surface of the second grating to form a hydrogen sensitive probe, the sensing film layer is an amorphous palladium-based alloy film, the hydrogen concentration in the environment is converted into the offset of the central wavelength of a substrate by utilizing the principle that the sensing film layer absorbs the stress and the refractive index of hydrogen are changed, and the hydrogen sensing system can greatly improve the stability and the sensitivity of the sensing system because the material has the reversible absorption performance of metal palladium on hydrogen and the excellent permeability of amorphous alloy on hydrogen. The surface of the first grating is exposed and used for temperature measurement and temperature compensation, and the problem of temperature cross sensitivity inherent in the fiber grating sensor is solved. The invention also provides two sensors for loading the hydrogen sensing system based on reflection and transmission spectrums respectively aiming at the type of the second grating.
Description
Technical Field
The invention belongs to the technical field of hydrogen sensors, and particularly relates to a fiber grating hydrogen sensing system based on amorphous palladium-based alloy. The invention also relates to a preparation method of the hydrogen sensor loaded with the sensing system.
Background
As one of the clean energy sources with the most application prospect, hydrogen has the characteristics of various sources, cleanness, low carbon, flexibility, high efficiency and the like, or becomes the ultimate form of future energy source use. It has been used in many fields, for example, as a reducing agent and a heat source in the metallurgical industry, and as a fuel for fuel cell vehicles. However, hydrogen is a colorless and odorless gas, has low ignition energy (at the lowest, only 0.02 mJ) and a large flame propagation speed, and is very easy to explode when exposed to open fire or current when the hydrogen content in the air is between 4.0% and 75%. Meanwhile, due to the small molecular volume and density, leakage is easy to occur and spread quickly in the processes of storage, transportation and use, and serious potential safety hazards are caused. Therefore, a precise and sensitive sensor needs to be developed, so that the hydrogen concentration in the environment can be quickly and effectively detected, and the safe and reliable use of hydrogen is ensured.
The optical fiber type sensor has the advantages of small volume, light weight, low power consumption, intrinsic safety, corrosion resistance, electromagnetic interference resistance, suitability for remote signal transmission and the like, can normally work in various complex environments, can meet the technical requirements of hydrogen sensors, and has wide application prospects. The probe part of the sensor is a passive device, so that electric sparks are not generated during monitoring, and the safety performance is obviously improved compared with other sensors. Classified according to the principle of operation, fiber optic sensors include primarily intensity-based, interference-based, and fiber grating-based sensors. The fiber grating sensor is easy to copy, has the unique advantage of reusability, has response based on wavelength coding, is more reliable and accurate compared with intensity-based measurement, and also has quasi-distributed sensing characteristics; compared with an optical fiber sensor based on interference, the optical fiber sensor based on interference has the advantages of simple structure, firm structure and lower cost. The fiber bragg grating is classified into a bragg grating (FBG), a Long Period Grating (LPG), a slanted grating (TFBG), and a chirped grating (CFBG) according to a difference in a grating structure. In the sensing field, FBG is the most widely used sensing device, and the high sensitivity characteristic of LPG makes it more and more interesting.
The sensing mechanism of the fiber grating hydrogen sensor is based on the change of the bragg wavelength of the grating caused by the hydrogen adsorbed to the hydrogen sensitive material coating, wherein the bragg grating depends on the mechanical expansion of the coating, and the long-period grating depends more on the change of the refractive index of the coating. Thus, the performance of the hydrogen sensitive material directly determines the performance of the hydrogen sensor. Palladium (Pd) metal is widely used as a hydrogen sensitive material in hydrogen sensors due to its reversible absorption and specific selectivity for hydrogen. However, the pure palladium film has the phenomena of bubbles, cracks and the like due to phase change caused by the high-concentration hydrogen entering the palladium, and the performance of the sensor is seriously influenced. To solve this problem, many researchers have studied to dope pure palladium with other elements such as nickel, gold, yttrium, etc. to prepare palladium-based alloy materials to improve the material properties. However, the palladium alloy membrane still has the problems of unstable hydrogen permeability, easy poisoning, thermal mismatch and the like. The amorphous alloy has remarkable advantages in mechanical strength, wear resistance, corrosion resistance and the like compared with the traditional crystalline alloy, and meanwhile, a plurality of loose atom clusters and free volumes in the amorphous alloy can provide potential hydrogen occupation, so that the hydrogen permeability of the amorphous alloy can be improved. And the use of non-noble metal in the amorphous alloy reduces the production cost for the preparation of the hydrogen sensitive material and has higher economy.
However, the fiber grating has the problem of cross sensitivity between strain and temperature, and in order to realize high-precision measurement, temperature compensation is usually required to be performed on a fiber grating sensing system. Patent CN105841840A proposes an optical fiber sensor capable of simultaneously measuring hydrogen concentration and temperature, which is essentially to realize simultaneous measurement of hydrogen concentration and temperature by monitoring the changes of interference spectrum generated by a coreless fiber and reflection spectrum generated by a bragg grating, but the loss of the coreless fiber is large and the stability is poor. Patent CN105572054A proposes an optical fiber hydrogen sensor with temperature compensation function, which utilizes two bragg gratings with the same parameters connected in series, and eliminates the temperature cross sensitivity by the difference of the shift of the central wavelength of the two bragg gratings, but the design of the same bragg grating has the disadvantage of decreasing the accuracy due to the confusion of the wavelength when the temperature or hydrogen concentration changes insignificantly.
Disclosure of Invention
In view of the defects of the prior art, a first object of the present invention is to provide a fiber grating hydrogen sensing system which has high stability and sensitivity, short recovery time, and can compensate for temperature. The hydrogen sensing system is formed by serially connecting and welding two fiber gratings with different central wavelengths, and an amorphous palladium-based alloy film is selected as a hydrogen sensitive material, and the material has the advantages of excellent hydrogen permeability, high mechanical strength, excellent wear resistance and corrosion resistance, good hydrogen embrittlement resistance effect, high sensitivity and the like.
The second purpose of the invention is to provide a preparation method of the hydrogen sensor loaded with the sensing system.
The invention is realized by the following technical scheme: the fiber grating hydrogen sensing system based on the amorphous palladium-based alloy film is characterized by comprising a hydrogen sensitive probe and a temperature probe, wherein the hydrogen sensitive probe consists of a second fiber grating, an adhesion layer and a sensing layer, and the sensing layer is the amorphous palladium-based alloy film. The temperature probe is composed of a first fiber grating which has different central wavelength from a second fiber grating and is exposed on the surface, and the first fiber grating and the second fiber grating are welded in a series connection mode.
The second grating in the hydrogen sensitive probe is a Bragg grating or a long-period grating, in order to increase the sensitivity of the probe, the grating can be processed by etching, tapering, mechanical polishing and the like, and the thickness of the outer coating layer of the processed grating is 1-80 mu m;
the adhesion layer in the hydrogen sensitive probe consists of a polyimide film and a Ni or Ti layer, and aims to enhance the combination effect between the grating and the sensing layer, wherein the thickness of the polyimide film is 0-20 mu m, and the thickness of the Ni or Ti layer is 0-100 nm;
the sensing layer in the hydrogen sensitive probe is an amorphous alloy film which is composed of more than three components, such as Pd-Ni-P, Pd-Cu-Ni-P, Pd-Cu-Si, and the like, and is a Pd-P or Pd-Si system. Preferably Pd-Cu-Si, wherein the atomic content of Si is 15% -25%;
the thickness of the amorphous alloy film of the sensing layer in the hydrogen sensitive probe is 1-1000 nm, and the ratio of the amorphous alloy film to the sectional area of the optical fiber is 0.001-100;
the sensing layer amorphous alloy film in the hydrogen sensitive probe is coated on the surface of the adhesion layer by a physical vapor deposition method, preferably a vacuum magnetron sputtering coating method;
the first grating in the temperature probe is a Bragg grating or a long-period grating, in order to increase the sensitivity of the probe, the grating can be processed by etching, tapering, mechanical polishing and the like, and the thickness of the outer coating layer of the processed grating is 1-80 mu m;
the types of the first grating in the temperature probe and the second grating in the hydrogen sensitive probe can be the same or different;
the central wavelength of the first grating in the temperature probe is at least 5 nm apart from the central wavelength of the second grating in the hydrogen sensitive probe, so as to avoid wavelength confusion when the temperature or hydrogen concentration change is not obvious;
the surface of a first grating in the temperature probe is exposed, and temperature change is converted into grating wavelength offset according to a thermal expansion principle, so that temperature measurement is realized;
the hydrogen-sensitive probe and the temperature probe are welded in series through an optical fiber welding machine;
the invention also provides a preparation method of the hydrogen sensor loaded with the sensing system, and the composition of the hydrogen sensor depends on the type selection of the second fiber bragg grating in the sensing system. When the second fiber bragg grating is a bragg grating, the hydrogen sensor comprises a light source, a sensing fiber, a coupler, a measuring gas chamber, a sensing system, a signal detection system, a tail fiber, a computer, a cable and the like; when the second fiber grating is a long-period grating, the hydrogen sensor comprises a light source, a sensing fiber, a measuring gas chamber, a sensing system, a signal detection system, a computer, a cable and the like;
the working principle of the invention is as follows: fiber gratings exposed to different temperatures are strained to different degrees, which causes wavelength shifts. The amorphous palladium-based alloy film coated on the second fiber grating can absorb and release hydrogen reversibly along with the change of the hydrogen concentration, the volume and the refractive index of the film can be changed correspondingly, the changes can cause further shift of the grating wavelength, namely, the second grating can not only respond to the change of temperature but also respond to the change of the hydrogen concentration. Because the surface of the first grating is exposed and has no hydrogen sensitive material coating, the surface of the first grating only responds to the change of temperature and is insensitive to the change of hydrogen concentration. The two are used together, and the wavelength signals from the two gratings are monitored simultaneously, so that the hydrogen concentration can be accurately compensated through a corresponding relational expression, and a compensation mechanism is based on the following formula:
wherein T is temperature (. degree. C.), λiIs the measured bragg wavelength (nm), λ, of the first and second grating (i = 1 or 2)i（0）Is the Bragg wavelength (nm), C, of two gratings at 0 deg.CTiAnd CΦiThe temperature coefficient (nm/° c) and the hydrogen concentration coefficient (nm/%) of the ith grating, and Φ is the hydrogen volume concentration (%).
The invention has the beneficial effects that:
(1) the invention relates to a fiber grating hydrogen sensing system and a fiber grating hydrogen sensing sensor, which are intrinsically safe passive devices.
(2) The invention combines the advantages of palladium metal and amorphous alloy to prepare the amorphous palladium-based alloy film which is used as a sensing layer material in a hydrogen sensitive probe. The material can effectively improve the hydrogen embrittlement phenomenon of the palladium continuous membrane and improve the stability of a hydrogen sensing system; compared with the traditional crystalline palladium alloy, the amorphous palladium alloy film has stronger hydrogen permeability and lower production cost, thereby shortening the response and recovery time of a hydrogen sensing system, reducing the production cost, simultaneously having excellent mechanical strength and wear resistance and corrosion resistance, and providing conditions for the use of a hydrogen sensor in severe environment.
(3) The hydrogen sensing system is formed by serially welding two fiber gratings with different central wavelengths, so that the problem of temperature cross sensitivity of the fiber gratings is solved, and the problem of disordered wavelength caused by using two gratings with the same parameters is also avoided. The accurate compensation of the hydrogen concentration is realized while two sets of data of the temperature and the hydrogen concentration are obtained.
(4) The invention provides a preparation method of a fiber grating hydrogen sensor based on amorphous palladium-based alloy aiming at the type selection of a second fiber grating, and the flexibility of equipment type selection is improved.
Drawings
Fig. 1 is a schematic structural diagram of a hydrogen sensitive probe in a hydrogen sensing system.
Fig. 2 is a schematic structural diagram of an amorphous palladium-based alloy-based fiber grating hydrogen sensor (the second grating is a bragg grating).
Fig. 3 is a schematic structural diagram of an amorphous palladium-based alloy-based fiber grating hydrogen sensor (the second grating is a long-period grating).
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings and the detailed description
Example 1
Referring to fig. 1, the optical fiber clad (2) on which the fiber bragg grating (1) is etched with hydrofluoric acid to reduce its thickness, thereby improving the sensitivity of the sensor. The corroded cladding is used as a substrate, and a polyimide film and a Ni film with certain thicknesses are sequentially coated to be used as an adhesion layer (3) so as to increase the adhesion between the sensing layer and the optical fiber cladding and prevent the hydrogen sensitive material from falling off. The amorphous palladium-based alloy film coated on the outer side of the adhesion layer forms a sensing layer (4) on the outermost side of the hydrogen sensitive probe, and the Pd-Cu-Si amorphous alloy film is selected as a hydrogen sensitive material, and the preparation method comprises the following steps: the coating method adopts a vacuum magnetron sputtering method, the target materials are a Pd target with the purity of 99.99 percent and a CuSi alloy target with the purity of 99.9 percent, and the atomic ratio of the CuSi alloy target is Cu: Si =5: 17; connecting a Pd target with a direct current power supply CuSi target and a radio frequency power supply; the thickness of the film is controlled by changing the current of the direct current power supply and the power of the radio frequency power supply, and finally the film is annealed. It is noted that the ratio of the cross-sectional area of the membrane to the cross-sectional area of the fiber will directly affect the sensitivity of the sensor and the time response, with sensitivity increasing with increasing ratio, but response time decreasing with increasing membrane thickness. In order to obtain a fast response optical fiber hydrogen sensor, the thickness of the thin film layer is selected to be 30 nm in this embodiment, and the diameter of the etched optical fiber is 50 μm in order to increase the sensitivity and ensure the mechanical strength.
Referring to the attached figure 2, the fiber grating hydrogen sensor based on the amorphous palladium-based alloy (the second grating is a bragg grating) is composed of a light source (5), a sensing optical fiber (6), a coupler (7), a measuring gas chamber (8), a sensing system (9), a signal detection system (12), a tail fiber (13), a computer (14) and a cable (15). The sensing system (9) arranged in the measurement gas chamber (8) consists of a hydrogen sensitive probe and a temperature probe, the structure of the hydrogen sensitive probe is shown as figure 1, the type of a second grating (11) in the hydrogen sensitive probe is a Bragg grating, the type of a first grating (10) in the temperature probe is also a Bragg grating, and the central wavelengths of the two gratings are separated by 5 nm. When light emitted by the light source (5) enters the sensing system (9), if the temperature in the measuring gas chamber (8) or the hydrogen concentration changes, the temperature and hydrogen concentration data can be obtained by monitoring the change of the reflection spectrum obtained by the signal detection system (12) and calculating by using the formulas 1 and 2. The end face of the pigtail (13) is polished or coated with an index matching gel to avoid fresnel reflection. And a cable (15) is used for connecting the signal detection system (12) and the computer (14) to realize analysis processing and display of data. The temperature compensation mechanism provided by the invention not only solves the problem of cross sensitivity of the temperature of the fiber grating sensor to the measurement of the hydrogen concentration, but also realizes the simultaneous monitoring of the temperature and the hydrogen concentration.
Example 2
In addition to etching or using ultra-fine bragg gratings to improve the sensitivity of fiber gratings, strategies using long-period gratings instead of bragg gratings have received much attention. Since the change in the long period grating wavelength is not only due to strain but also due to changes in the refractive index of the cladding and coating. Also, if the coating thickness is sufficiently small, the effect of strain on wavelength shift can be neglected. In the present embodiment, therefore, the second grating type is selected to be changed to a long-period grating. And since LPG itself has a higher sensitivity than FBG, the thickness of the Pd-Cu-Si thin layer in this embodiment example is chosen to be 15 nm to obtain a shorter response and recovery time. The preparation of the sensor system (9) was carried out in the same manner as in example 1, except for the two parameters mentioned above.
However, because LPG is coupling between the core fundamental mode and the cladding mode of the co-transmission and there is no backward transmission, when the second grating is a long-period grating, the structure of the fiber grating hydrogen sensor of the present invention is shown in fig. 3. Compared with the sensor structure shown in fig. 2, the second grating type is changed from a bragg grating into a long-period grating (11), a coupler (7) and a tail fiber (13) are removed, and temperature and hydrogen concentration data can be obtained by monitoring the change of the transmission spectrum obtained by a signal detection system (12) and calculating by using the formulas 1 and 2.
Further, in the implementation of the present invention, the selection of the sensor structure (fig. 2 or fig. 3) is determined by the selection type of the second grating, and the type of the grating (i.e., the first grating) selected for the temperature probe may be a bragg grating or a long-period grating. FBGs have lower production costs and higher multiplexing capabilities, while LPG has a larger temperature coefficient.
The above description is only an example of the present invention, and is not intended to limit the scope of the present invention. It should be understood that the technical solutions and the inventive concepts according to the present invention may be equally replaced or changed by those skilled in the art, and all such changes or substitutions should fall within the protection scope of the present invention.
Claims (7)
1. The fiber grating hydrogen sensing system based on the amorphous palladium-based alloy film is characterized by comprising a hydrogen sensitive probe and a temperature probe, wherein the hydrogen sensitive probe consists of a second fiber grating, an adhesion layer and a sensing layer, the sensing layer is the amorphous palladium-based alloy film, the temperature probe consists of a first fiber grating which has different central wavelength from the second fiber grating and is exposed on the surface, and the first fiber grating and the second fiber grating are welded in series.
2. The hydrogen sensing system according to claim 1, wherein the second grating in the hydrogen sensitive probe is a bragg grating or a long period grating, the grating can be processed by etching, tapering, mechanical polishing and the like to increase the sensitivity of the probe, and the thickness of the outer coating of the grating after processing is 1-80 μm.
3. A hydrogen sensing system according to claim 1, wherein the adhesion layer in the hydrogen sensitive probe consists of a polyimide film having a thickness of 0-20 μm and a Ni or Ti layer having a thickness of 0-100 nm.
4. A hydrogen sensing system according to claim 1, wherein the sensing layer in the hydrogen sensitive probe is an amorphous alloy thin film composed of three or more components of Pd-P or Pd-Si system, the thickness of the thin film is 1 to 1000 nm, and the ratio of the cross-sectional area of the thin film to that of the optical fiber is 0.001 to 100.
5. The hydrogen sensing system according to claim 1, wherein the sensing layer amorphous alloy thin film in the hydrogen sensitive probe is coated on the surface of the adhesion layer by a physical vapor deposition method.
6. A hydrogen sensing system according to claim 1, wherein the first grating in the temperature probe is of the bragg grating or the long period grating, and the second grating is of the same or different type, and the thickness of the outer cladding layer of the grating is 1-80 μm.
7. A hydrogen sensor loaded with a hydrogen sensing system according to any one of claims 1 to 6, wherein the shape selection of the second fiber grating in the sensing system determines the composition of the hydrogen sensor, and specifically comprises: when the second fiber bragg grating is a bragg grating, the hydrogen sensor comprises a light source, a sensing fiber, a coupler, a measuring gas chamber, a sensing system, a signal detection system, a tail fiber, a computer, a cable and the like; when the second fiber grating is a long-period grating, the hydrogen sensor comprises a light source, a sensing fiber, a measuring gas chamber, a sensing system, a signal detection system, a computer, a cable and the like.
Priority Applications (1)
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114235686A (en) * | 2021-11-05 | 2022-03-25 | 安徽伯华氢能源科技有限公司 | Optical fiber type palladium-based film hydrogen sensing system and sensor with amorphous structure |
| CN116399472A (en) * | 2023-06-09 | 2023-07-07 | 中国华能集团清洁能源技术研究院有限公司 | Safety monitoring device and method for liquid-cooled battery pack and module-level safety monitoring device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114235686A (en) * | 2021-11-05 | 2022-03-25 | 安徽伯华氢能源科技有限公司 | Optical fiber type palladium-based film hydrogen sensing system and sensor with amorphous structure |
| CN116399472A (en) * | 2023-06-09 | 2023-07-07 | 中国华能集团清洁能源技术研究院有限公司 | Safety monitoring device and method for liquid-cooled battery pack and module-level safety monitoring device |
| CN116399472B (en) * | 2023-06-09 | 2024-03-22 | 中国华能集团清洁能源技术研究院有限公司 | Safety monitoring device and method for liquid-cooled battery pack and module-level safety monitoring device |
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