JP7568210B2 - Analysis system and analysis method - Google Patents

Description

The present invention relates to an analysis system and an analysis method.

Spectroscopic measurements are used for qualitative or quantitative analysis of samples. For example, coherent anti-Stokesman scattering, a type of spectroscopy, is used to measure water molecules in electrolyte membranes used in fuel cells (see Patent Document 1). Spectroscopic methods allow for non-destructive and non-contact measurements, and are particularly useful for product evaluation.

JP 2016-156813 A

To increase the spatial resolution of a spectrometer, the irradiated light is usually focused. Also, the emission intensity is measured at multiple positions by changing the position at which the light is irradiated. The more the irradiated light is focused and the more finely the irradiated position is changed, the higher the spatial resolution.

However, there is a limit to how much the irradiated light can be narrowed. If the irradiated light is narrowed too much, the sample may be damaged. Also, the more measurements are taken, the longer it takes to measure and analyze the results.

The purpose of the present invention is to obtain continuous distribution of a substance through simple measurement.

An analytical system (100) according to one aspect of the present invention includes a spectrometer (30) that irradiates a sample with measurement light and measures the luminescence intensity of the sample, and a diagnostic device (50) that analyzes the sample based on the measurement results of the luminescence intensity, and the diagnostic device (50) calculates a continuous concentration distribution of the substance to be analyzed contained in the sample based on the measurement results of the luminescence intensity and the intensity distribution of the irradiated light.

Another aspect of the present invention is an analytical method that irradiates a sample with measurement light and analyzes the sample based on the emission intensity of the sample, and includes a step of calculating a continuous concentration distribution of the substance to be analyzed contained in the sample based on the measurement result of the emission intensity and the intensity distribution of the irradiated light.

According to the present invention, continuous distribution of a substance can be obtained through simple measurements.

FIG. 1 is a schematic diagram illustrating an example of the configuration of an analysis system according to an embodiment of the present invention. FIG. 1 is a perspective view of a fuel cell. FIG. 2 is a cross-sectional view showing the configuration of a cell. FIG. 1 is a schematic diagram showing a configuration example of a CARS spectrometer. 1A and 1B are schematic diagrams illustrating a method for measuring the intensity distribution of measurement light. FIG. 1 is a schematic diagram for explaining a method for calculating the luminescence intensity of a substance in a certain region. 1 is a graph showing an example of a profile representing a continuous distribution of water contained in an electrolyte membrane. 1 is a graph showing an example of a profile showing the correlation between the output voltage of a fuel cell and the intensity of light originating from water in an electrolyte membrane.

Below, an embodiment of the analysis system and analysis method of the present invention will be described with reference to the drawings. The configuration described below is one example (representative example) of the present invention, and the present invention is not limited to this configuration.

In the following embodiment, an example of analyzing a fuel cell that is mounted on a vehicle and supplies driving power to the vehicle is described, but the present invention can also be applied to the analysis of fuel cells in the power generation systems of other mobile bodies such as trains, stationary power generation systems, and the like, in addition to vehicles. Furthermore, the present invention is not limited to fuel cells and can also be applied to the analysis of other samples.

FIG. 1 shows an example of the configuration of an analysis system 100 according to an embodiment of the present invention.
As shown in FIG. 1, the analytical system 100 includes a spectrometer 30 and a diagnostic device 50 .

The analysis system 100 of this embodiment is mounted on a vehicle 200 together with a fuel cell 10 to be analyzed and its control device 60. The control device 60 controls the output voltage of the fuel cell 10 based on signals from various sensors mounted on the vehicle 200. The control device 60 is, for example, an electronic control unit (ECU).

(Fuel Cell)
FIG. 2 is a perspective view of the fuel cell 10.
As shown in FIG. 2, the fuel cell 10 includes a stack 10a and a casing 10b.
The stack 10a is surrounded by a casing 10b and sealed therewith.

The stack 10a consists of multiple plate-like cells 11 stacked in a row. The periphery of the cells 11 is covered and sealed by sealing rubber 12.

FIG. 3 shows an example of the configuration of the cell 11.
3, the cell 11 includes a membrane electrode assembly (MEA) 3, a pair of separators 4, and a subgasket 5. The MEA 3 includes an electrolyte membrane 1 and a pair of electrodes 2. The pair of electrodes 2 and the pair of separators 4 are arranged to sandwich the electrolyte membrane 1, and the electrodes 2 and the separators 4 are laminated on both sides of the electrolyte membrane 1, respectively.

The electrolyte membrane 1, the electrode 2, and the separator 4 are stacked in the z direction. The peripheral portions of the electrolyte membrane 1 and the electrode 2 that are not covered by the separator 4 are covered and sealed by the sealing rubber 12.

In the stack 10a, multiple cells 11 are stacked in the z direction, which is the same as the stacking direction of the electrolyte membrane 1, electrodes 2, and separators 4. The x and y directions are directions that are perpendicular to the z direction within the plane of the cell 11.

The electrolyte membrane 1 is an ion-conductive polymer electrolyte membrane. Examples of the electrolyte membrane 1 include perfluorosulfonic acid polymers such as Nafion (registered trademark) and Aquivion (registered trademark); aromatic polymers such as sulfonated polyether ether ketone (SPEEK) and sulfonated polyimide; and aliphatic polymers such as polyvinyl sulfonic acid and polyvinyl phosphoric acid.

From the viewpoint of improving durability, the electrolyte membrane 1 may be a composite membrane in which a porous substrate 1a is impregnated with a polymer electrolyte. The porous substrate 1a is not particularly limited as long as it can support the polymer electrolyte, and a membrane in the form of a porous, woven, nonwoven, or fibril can be used. The material of the porous substrate 1a is also not particularly limited, but from the viewpoint of increasing ion conductivity, the above-mentioned polymer electrolyte can be used. Among them, fluorine-based polymers such as polytetrafluoroethylene, polytetrafluoroethylene-chlorotrifluoroethylene copolymer, and polychlorotrifluoroethylene have excellent strength and shape stability.

Of the pair of electrodes 2, one electrode 2 is an anode, also called a fuel electrode. The other electrode 2 is a cathode, also called an air electrode. Hydrogen gas is supplied to the anode as a fuel gas, and oxygen gas or air containing oxygen gas is supplied to the cathode.

Hydrogen gas (H ₂ ) is supplied to the anode, and a reaction occurs in which electrons (e ^- ) and protons (H ⁺ ) are generated from the hydrogen gas (H ₂ ). The electrons move to the cathode via an external circuit (not shown). This movement of electrons generates a current in the external circuit. The protons move to the cathode via the electrolyte membrane 1.

Oxygen gas (O ₂ ) is supplied to the cathode, and oxygen ions (O ₂ ^- ) are generated by electrons transferred from an external circuit. The oxygen ions combine with protons (2H ⁺ ) transferred from the electrolyte membrane 1 to become water (H ₂ O).

The electrode 2 includes a catalyst layer 21. In this embodiment, the electrode 2 further includes a gas diffusion layer 22 to improve the diffusibility of the fuel gas.

The catalyst layer 21 promotes the reaction between hydrogen gas and oxygen gas by the catalyst. The catalyst layer 21 includes a catalyst, a carrier that supports the catalyst, and an ionomer that coats the catalyst and the carrier.
Examples of the catalyst include metals such as platinum (Pt), ruthenium (Ru), iridium (Ir), rhodium (Rh), palladium (Pd), cobalt (Co), and tungsten (W), as well as mixtures and alloys of these metals. Among these, platinum, mixtures and alloys containing platinum are preferred from the viewpoints of catalytic activity, resistance to poisoning by carbon monoxide, heat resistance, and the like.

Examples of the carrier include mesoporous carbon and conductive metal compounds such as titanium oxide. Mesoporous carbon is preferred from the viewpoints of good dispersibility, large surface area, and little particle growth at high temperatures even when a large amount of catalyst is supported.
As the ionomer, an ion-conductive polymer electrolyte similar to that of the electrolyte membrane 1 can be used.

The gas diffusion layer 22 can uniformly diffuse the supplied fuel gas to the catalyst layer 21. As the gas diffusion layer 22, for example, a porous fiber sheet such as carbon fiber having electrical conductivity, gas permeability, and gas diffusion properties, as well as a metal plate such as foamed metal or expanded metal can be used.

The separator 4 is a plate with multiple ribs 4b on its surface, and is also called a bipolar plate. Each rib 4b creates a recess 4a on the surface of the separator 4. The recess 4a forms a flow path for the fuel gas between the separator 4 and the MEA 3. This flow path also serves as a drain for water produced by the reaction of the fuel gas.

Materials for the separator 4 include, for example, carbon and metals such as stainless steel.

The subgasket 5 is a film or plate that surrounds the outer periphery of the MEA 3 and functions as a support for the MEA 3. The material of the subgasket 5 can be a resin with low electrical conductivity. There are no particular limitations on the resin material, and examples include polyphenylene sulfide (PPS), glass-filled polypropylene (PP-G), polystyrene (PS), silicone resin, and fluorine-based resin.

The subgasket 5 seals the inside of the cell 11 by abutting against the separator 4 at its outer peripheral edge.

(window)
The fuel cell 10 has windows B1 to B3 that communicate from the outside of the fuel cell 10 to the internal MEA 3. The window B1 is provided in the casing 10b, and the window B2 is provided in the sealing rubber 12. The window B3 is provided in the separator 4, the gas diffusion layer 22, and the catalyst layer 21.

The windows B1 and B2 may be open in any of the x, y and z directions. The window B3 opens in the z direction and communicates with the window B1 which also opens in the z direction.
The windows B1 to B3 may be simple openings, but from the viewpoint of sealing, they may be openings provided with glass plates or plates made of a light-transmitting material other than glass.

The spectrometer 30 can irradiate laser light onto the MEA 3 inside the fuel cell 10 from the peripheral side where the separator 4 is not arranged or from the separator 4 side through these windows B1 to B3, and receive light from the MEA 3. The optical path between the spectrometer 30 and the MEA 3 can be formed by an optical system such as a mirror, an optical fiber, a waveguide, etc.

(Spectrometer)
The spectrometer 30 irradiates a sample with light for measurement, such as laser light, receives light such as reflected light, scattered light, and emitted light (hereinafter, these are collectively referred to as emission light) generated from the sample by the irradiation of the laser light, and measures the intensity of the emission light.

Spectroscopic analysis methods used by the spectrometer 30 include, for example, Coherent Anti-Stokes Raman Scattering (CARS), Raman spectroscopy, Infrared Spectroscopy (IR), and Fourier Transform Infrared Spectroscopy (FT-IR).

In particular, it is preferable that the spectrometer 30 is a CARS spectrometer that performs measurements using the CARS method. A CARS spectrometer has a higher time resolution than other spectroscopic analysis methods such as Raman spectroscopy. For example, the time resolution of a neutron detector requires 10 seconds or more for detection, but a CARS spectrometer can perform detection in less than 1 second, making it possible to analyze the internal state of the fuel cell 10 in real time.

A CARS spectrometer irradiates a sample with two laser beams of different angular frequencies and measures the intensity of the CARS light generated from the sample.

FIG. 4 shows an example of the configuration of the CARS spectrometer 30A.
4, the CARS spectrometer 30A includes a light source 31, an optical splitter 32, converters 33 and 34, a delay circuit 35, a detector 36, and a probe 38. The optical path in the CARS spectrometer 30A is formed by an optical system such as a mirror (not shown), but may be formed by an optical fiber, a waveguide, or the like.

In the CARS spectrometer 30A, the laser light emitted from the light source 31 is split into two laser lights by the optical splitter 32. Examples of the light source 31 include a titanium sapphire laser and a pulsed laser light source. Examples of the optical splitter 32 include optical systems such as a dichroic mirror and a half mirror, as well as a waveguide with a branch, an optical fiber, etc.

One of the split laser beams is converted by the converter 33 into Stokes light L2 with angular frequency ω2. Examples of the converter 33 include a photonic crystal fiber and an optical parametric oscillator. The Stokes light L2 may be white light containing light of different wavelengths. By using the Stokes light L2 with a wide wavelength range, it is possible to detect a wide variety of vibration modes.

The other branched laser light is converted by the converter 34 into pump light L1 with angular frequency ω1. Examples of the converter 34 include a photonic crystal fiber and an optical parametric oscillator. The angular frequency ω1 of the pump light L1 is higher than the angular frequency ω2 of the Stokes light L2. The pump light L1 is guided to the same optical path as the Stokes light L2 via the delay circuit 35.

The Stokes light L2 and the pump light L1 are focused by the probe 38 and irradiated onto the sample S. The pump light L1 passes through the delay circuit 35, and is irradiated onto the sample S with a delay relative to the Stokes light L2. When the difference in angular frequency (ω1-ω2) between the pump light L1 and the Stokes light L2 matches the inherent vibration mode of the substance in the sample S, the molecular dipole moment is resonantly induced, and CARS light L3 with an angular frequency of 2ω1-ω2 is generated.

The detector 36 detects the intensity of CARS light Lc with an angular frequency of 2ω1-ω2, which is generated from the sample S by irradiation with the Stokes light L2 and the pump light L1. The detector 36 is composed of a photoelectric conversion element such as a spectrometer, a CCD (Charge Coupled Device), or an ICCD (Intensified CCD), but is not limited to these as long as it can measure the intensity of light at each wavelength.

When the laser light is irradiated from the separator 4 side through the windows B1 and B3, the position in the x, y or z direction where the laser light is irradiated can be changed by changing the focal position of the laser light of the spectrometer 30 in the x and y directions (in-plane directions) or in the z direction (thickness direction). When the laser light is irradiated from the peripheral edge side of the electrolyte membrane 1 through the windows B1 and B2, the in-plane position where the laser light is irradiated can be changed by changing the position or attitude of the probe 38, for example. By changing the irradiation position, it is also possible to switch the sample S to the electrolyte membrane 1 or the electrode 2.

(Diagnostic device)
The diagnostic device 50 performs qualitative or quantitative analysis of the analysis target in the fuel cell 10 based on the measurement results by the spectrometer 30. As the diagnostic device 50, for example, a computer equipped with a CPU, a memory for storing a program executed by the CPU, etc., or a microcomputer can be used.

Qualitative analysis can be performed by identifying peaks due to vibrational modes between atoms that comprise the substance to be analyzed in the spectrum of light intensity obtained by the spectrometer 30. For example, a peak due to Pt-Pt molecules appears near 200 cm ⁻¹ , and a peak due to water molecules appears near 3500 cm ⁻¹ .

The method of quantitative analysis is not particularly limited, but for example, the amount of the substance to be analyzed can be calculated using reference data. The reference data is data in which the intensity of light detected by the spectrometer 30 is associated with the amount of the substance to be analyzed, the amount of which is known. The intensity of light can be calculated as the intensity or area of a peak resulting from the vibration mode of the substance that contains the substance to be analyzed.

The analysis targets include the electrolyte membrane 1, platinum contained in the electrolyte membrane 1, platinum compounds such as platinum oxide, or water. For example, the diagnostic device 50 can analyze the electrolyte membrane 1, platinum, platinum compounds, or water in the electrolyte membrane 1 based on the measurement results of the thickness direction (z direction) or in-plane direction (x-y plane) of the electrolyte membrane 1 by the spectrometer 30, thereby creating a profile of platinum or water distributed in the thickness direction or in-plane direction of the electrolyte membrane 1. From such a decomposition profile of the electrolyte membrane 1, the decomposition process of the electrolyte membrane 1 can be understood. In addition, from the platinum or water profile, the phenomenon of platinum band formation in which platinum dissolves from the catalyst layer 21 into the electrolyte membrane 1 can be understood.

The subject of analysis may be not only the electrolyte membrane 1, but also platinum or platinum compounds in the electrode 2 or subgasket 5. By such an analysis, it is possible to ascertain the amount of platinum eluted from the electrode 2 or the amount of platinum eluted into the subgasket 5, etc.

The subject of analysis may be a metal or metal compound other than platinum, such as nickel or chromium, in the electrolyte membrane 1, the electrode 2, or the subgasket 5. Such an analysis can identify the presence of metal impurities.

(Analysis method of analysis system)
The above-mentioned analysis system 100 calculates the continuous concentration distribution of the substance to be analyzed in the sample S by the diagnostic device 50 based on the emission intensity measurement results by the spectrometer 30 and the intensity distribution of the irradiated light from the spectrometer 30. A specific description will be given below.

First, the spectrometer 30 measures the three-dimensional intensity distribution of the light irradiated for measurement. To reduce fluctuations in the intensity distribution, the environmental conditions during measurement, such as temperature and humidity, are kept constant.

FIG. 5 shows an example of a method for measuring the intensity distribution of the measurement light.
As shown in Fig. 5, the light L0 irradiated in the z direction from the spectrometer 30 is cut out in the xy plane, and the light intensity at each position (x, y) on the xy plane is measured. For example, a CCD or the like may be used for the measurement. This measurement is repeated by changing the position in the z direction, and the light intensity at multiple three-dimensional positions (x, y, z) is obtained. A continuous light intensity distribution may be obtained by interpolating the actual measured values. Note that the light diameter of the irradiated light L0 becomes smaller as it approaches the focal position.

Next, the light L0 is irradiated onto the sample S by the spectrometer 30, and the intensity of the light emission L3 from the sample S is measured. The environmental conditions at this time are preferably the same as those when the intensity distribution of the irradiated light L0 was measured. The diagnostic device 50 uses the measurement results to calculate the concentration distribution of the substance.
An example of calculating the three-dimensional concentration distribution of a substance contained in a cubic region V in a sample S as shown in FIG. 6 will be described below.

The cubic region V is further divided into smaller cubic regions. In this example, it is divided into 10 ⁹ regions. The position (x, y, z) of each divided region is expressed as (0, 0, 0) to (10 ⁹ , 10 ⁹ , 10 ⁹ ). The light intensity of the emitted light L3 in each divided region increases monotonically (for example, proportionally) as the intensity of the light L0 increases. Since the irradiated light L0 has a spread, the diagnostic device 50 performs the following calculation assuming that all of the irradiated light L0 is irradiated to the entire region V.

From the measurement results of the light intensity of each position (x, y, z) of the irradiated light L0, the diagnostic device 50 calculates the ratio of the light intensity of the light L0 irradiated to each divided region (0, 0, 0) to (10 ⁹ , 10 ⁹ , 10 ⁹ ), and sets the ratio as a coefficient m(x, y, z) (%) for each divided region (0, 0 ^, 0) to (10 ⁹ , 10 9 , 10 ⁹ ). The sum of the coefficients m(x, y, z) for each divided region is 100%. Note that, if it is assumed that there is a limit to the range irradiated with the light L0, the diagnostic device 50 may set the coefficient m(x, y, z) = 0 for the divided regions in region V that are not irradiated with the light L0.

The diagnostic device 50 defines a function F(x, y, z) that represents a three-dimensional concentration distribution of a substance using i parameters, where i is a natural number. For example, the function F(x, y, z) is expressed by the following polynomial (1) using five parameters a to e.
(1) F(x, y, z)
=a×x ² +b×y ² +c×x+d×y+e×z

The function F(x, y, z) is not limited to equation (1), and any appropriately designed equation can be used. For example, the accuracy of the concentration distribution can be improved by using a higher-dimensional polynomial. The accuracy of the concentration distribution can also be improved by designing an equation according to the properties of the substance. For example, in the case of water, since it is expected that there is more water in the direction of gravity, an equation weighted in the direction of gravity may be used.

When the intensity I(x, y, z) of the light emission L3 obtained from the target substance in each divided region is proportional to the concentration D of the substance, the relational expression I=R×D holds, where R is a coefficient expressing the relationship between concentration and light emission. In addition, since the intensity I(x, y, z) is also proportional to the intensity of the irradiated light L0, the concentration D can be expressed as follows using a function F(x, y, z):
I(0,0,0)
= {a×0 ² +b×0 ² +c×0+d×0+e×0}×R×m(0,0,0)
I(0,0,1)
= {a×0 ² +b×0 ² +c×0+d×0+e×1}×R×m(0,0,1)
...
I (10 ⁹ , 10 ⁹ , 10 ⁹ )
= {a×(10 ⁹ ) ² +b×(10 ⁹ ) ² +c×(10 ⁹ )+d×(10 ⁹ )
+e×(10 ⁹ )}×R×m(10 ⁹ ,10 ⁹ ,10 ⁹ )

Since the light intensity of the emission L3 is equal to the sum of the intensities I(x, y, z) of the divided regions, the following formula (2) is established. The diagnostic device 50 inputs the measurement result of the emission intensity by the spectrometer 30 as the left side of formula (2) to obtain a relational expression of parameters a to e. The measurement result input here is the measurement result of the emission intensity obtained from the substance to be analyzed. For example, when the substance to be analyzed is water, the peak intensity derived from water or the like is input.

Meanwhile, the spectrometer 30 measures the intensity of the light emission L3 by varying the irradiation position of the irradiation light L0 on the sample S in the z direction. The diagnostic device 50 calculates the relational equation of the parameters a to e from equation (2) in the same manner as above for fixed regions with different positions in the z direction. In fixed regions with different positions, the light intensity I(x, y, z) of each divided region is different, and therefore a different relational equation is obtained from the previous measurement.

The measurement of the light intensity I of the light emission L3 and the calculation of equation (2) are performed at least i times, which is the same as the number of parameters. For parameters a to e, a five-dimensional simultaneous equation is obtained from equation (2) by five measurements. The diagnostic device 50 calculates the parameters a to e by solving this simultaneous equation. The diagnostic device 50 inputs the calculated parameters a to e into equation (1) to obtain a function F(x, y, z) that represents the concentration distribution of the substance. This concentration distribution is a distribution in a three-dimensional region that includes the irradiation position of the light L0 irradiated in the five measurements.

In the i measurements, the irradiation range of light L0 may or may not overlap. If there is overlap, the accuracy of the concentration distribution calculation is likely to improve. If there is no overlap, the concentration distribution over a wide range can be calculated. Although i measurements are required to calculate the concentration distribution, the accuracy of the calculation can be further improved by measuring more than i times.

When the spectrometer 30 is a CARS spectrometer 30A, the intensity of the CARS light L3 generated by irradiation with the pump light L1 of angular frequency ω1 and the Stokes light L2 of angular frequency ω2 is proportional to ω1 ² ×ω2. The angular frequencies ω1 and ω2 include the intensities of the pump light L1 and the Stokes light L2, respectively. The diagnostic device 50 calculates the distribution of ω1 ² ×ω2 from the intensity distributions of the pump light L1 and the Stokes light L2. The diagnostic device 50 calculates the coefficient m(x, y, z) of each divided region (x, y, z) from the distribution of ω1 ² ×ω2, and uses it in the calculation of equation (2).

The intensity distribution of the irradiated light L0 may be measured each time an analysis of the sample S is performed. Alternatively, the intensity distribution measured once may be stored in the diagnostic device 50 and used repeatedly in subsequent analyses of the sample S.

FIG. 7 shows an example of a profile representing the distribution of water generated by the diagnostic device 50. In FIG.
In the profile shown in Fig. 7, the horizontal axis represents the z-direction position from 0 µm to 10 µm in contact with the cathode. The vertical axis represents the intensity K of the luminescence originating from water measured by the spectrometer 30. The greater the intensity K, the more water is present at the position. In this profile, the luminescence intensity K at each position in the z direction is continuous, and represents a continuous concentration distribution of water.

The analysis system 100 can also create profiles other than the profile that represents the continuous distribution of the analysis target. For example, the analysis system 100 can more accurately measure phenomena such as water transport or platinum elution during operation by creating a profile that represents the correlation between the output voltage of the fuel cell 10 and the intensity of luminescence originating from water or platinum in the electrolyte membrane 1.

FIG. 8 shows an example of a profile showing the correlation between the output voltage of the fuel cell 10 and the intensity K of the luminescence originating from water measured in the thickness direction of the electrolyte membrane 1. In FIG.
In this profile, the emission intensity K measured at regular intervals at points 0, 5, 10, 15 and 20 μm away from the cathode in the thickness direction (z direction) is plotted.

While the fuel cell 10 is generating electricity at an output voltage of 0.1 A/ ^cm3 , there is little change in the intensity K, and the intensity K decreases the further away from the cathode. However, when the output voltage is increased from 0.1 A/ ^cm3 to 1.0 A/ ^cm3 at time T1, the intensity K increases overall due to the sudden increase in output voltage, and it can be analyzed that a lot of water is being generated. The intensity K increases the closer to the cathode, and a particularly sudden increase in water is observed at the 0 μm point in contact with the cathode.

(Determination of fuel cell properties)
The diagnostic device 50 can determine various physical properties of the fuel cell 10 based on the analysis results of the fuel cell 10. For example, the diagnostic device 50 can determine physical properties such as the water permeability coefficient, electro-osmosis coefficient, and thickness of the electrolyte membrane 1, and the water diffusion coefficient of the gas diffusion layer 22, based on the profile of water contained in the electrolyte membrane 1.

Normally, a simulation is performed by calculation based on the physical properties of the material used in the electrolyte membrane 1, and the optimum membrane properties such as the water diffusion coefficient, electric vibration coefficient, and thickness are determined based on the results. However, the results of the simulation by calculation may deviate from the actual optimum membrane properties.

In contrast, according to this embodiment, a profile can be created by analyzing a fuel cell 10 that is actually in operation as a product. Because the water transport phenomenon in the fuel cell 10 is actually measured, rather than calculated, it is possible to select more optimal membrane properties.

In addition, in order to fill in the gap between the actual optimum film properties during simulation, actual measured values may be used as auxiliary values, and the profile actually measured in this embodiment may be used as the actual measured values. Combining with simulation makes it possible to select more useful film properties.

As described above, according to this embodiment, the diagnostic device 50 defines a function F(x, y, z) that represents the concentration distribution of a substance in a certain area irradiated with light L0 using i parameters. The spectrometer 30 repeats measuring the intensity of the light emission i times by changing the irradiation position of the light L0. The diagnostic device 50 calculates a relational expression (e.g., equation (2)) between the intensity I(x, y, z) of the light emission L3 calculated from the intensity distribution of the light L0 and the function F(x, y, z) that represents the concentration of the substance, and the measurement result of the intensity I of the light emission L3 by the spectrometer 30. The diagnostic device 50 calculates i parameters based on the i relational expressions obtained by the i measurements, and obtains the relational expression F(x, y, z) in which the parameters are specified.

This makes it possible to calculate a continuous concentration distribution of a substance without narrowing the measurement light emitted from the spectrometer 30. Since the concentration distribution can be calculated by at least i measurements, which is the same as the number of parameters, a wide range of concentration distribution can be obtained by simple measurements with a small number of measurements. In addition, damage to the sample S caused by narrowing the light too much can be reduced.

In the above embodiment, the concentration distribution is calculated by multiple measurements to improve the accuracy of the calculation, but if the intensity distribution of the irradiated light L0 is used in the calculation, the concentration distribution may be obtained by a single measurement.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

For example, in the above embodiment, the analysis system 100 analyzes the fuel cell 200 while it is generating electricity on the vehicle 200, but the analysis may also be performed on the fuel cell 200 connected to an experimental load instead of the vehicle 200.

In addition, the sample is not limited to the fuel cell 10, and the present invention can be applied to various samples such as intracellular biomolecules.

100: Analysis system, 30: Spectrometer, 31: Light source, 33, 34: Converter, 36: Detector, 50: Diagnostic device, 10: Fuel cell, 1: Electrolyte membrane, 2: Electrode, 21: Catalyst layer, 22: Gas diffusion layer, 3: MEA, 4: Separator, 5: Subgasket, B1 to B3: Windows

Claims (7)

A spectrometer (30) for irradiating a sample with measurement light and measuring the emission intensity at the sample;
a diagnostic device (50) for analyzing the sample based on the measurement result of the luminescence intensity;
Equipped with
the diagnostic device (50) calculates a continuous concentration distribution of the substance to be analyzed contained in the sample based on the measurement result of the luminescence intensity and the intensity distribution of the light irradiated onto the sample.
An analysis system (100). The spectrometer (30) moves the position of the irradiated light in the thickness direction or in-plane direction of the sample, and repeats the measurement of the emission intensity multiple times;
The diagnostic device (50) calculates a continuous concentration distribution of the substance to be analyzed contained in the sample based on the results of multiple measurements of the luminescence intensity and the intensity distribution of the light irradiated onto the sample.
The analytical system (100) of claim 1. The diagnostic device (50) calculates a concentration distribution of the substance in a three-dimensional region.
The analytical system (100) of claim 1 or 2. The measurement light is two laser beams having different angular frequencies,
The spectrometer (30) is a CARS spectrometer that irradiates the sample with two laser beams having different angular frequencies and measures the intensity of CARS light generated from the sample.
An analytical system (100) according to any one of claims 1 to 3. The light emission intensity is proportional to the product of the square of the intensity of the irradiated light having the higher angular frequency and the intensity of the irradiated light having the lower angular frequency.
The analytical system (100) of claim 4. The sample is an electrolyte membrane (1) included in a fuel cell (10), or a pair of electrodes (2) arranged on both sides of the electrolyte membrane (1);
The analysis system (100) according to any one of claims 1 to 5, wherein the analysis target is a metal, a metal compound, or water contained in the electrolyte membrane (1) or the electrode (2). 1. An analysis method comprising: irradiating a sample with light for measurement and analyzing the sample based on a light emission intensity of the sample, the method comprising:
calculating a continuous concentration distribution of an analyte substance contained in the sample based on the emission intensity measurement result and the intensity distribution of the light irradiated onto the sample;
Analysis methods.

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