JPH09161836A - Fuel cell measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent measuring failure, caused between a measuring line and a measured data line, by connecting a relay wire, for relaying the measuring line for transmitting the measured result of the operation condition of a fuel cell main body, and the measured data line for transmitting the measured result outside a pressure vessel. SOLUTION: A through terminal 18 is fitted to a pressure 10 so that a connecting part can keep airtightness, by an O ring 16 and the fitting part 17 of a penetrating terminal 18 fitted to the outer side of the pressure vessel 10 from the inner side of the pressure vessel 10. A relay wire 12, connected to a voltage observing device on the outer side of the pressure vessel 10, and a measuring line 13, for transmitting the measured result by a measuring means for measuring the operation condition of a fuel cell main body, are connected by a pin 23 at the inside of the penetrating terminal 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell measuring device for monitoring the operating condition of a fuel cell.

[0002]

2. Description of the Related Art A fuel cell is a device that directly oxidizes the chemical energy of a fuel in an electrochemical process to directly convert the energy released by the oxidation reaction into electrical energy.

This fuel cell system has a power generation efficiency of 40% even on a comparatively small scale, and has been conventionally expected to far surpass new thermal power generation. In addition, SOx and NO, which are pollution factors that have become a major social problem in recent years,
In principle, high conversion efficiency can be expected, such as extremely low x emission, no need for a large amount of cooling water because the power generator does not include a combustion cycle, and small vibration.
Since there are few environmental problems such as noise and exhaust gas, and it has the characteristics that it has good responsiveness to load fluctuations, it is expected and interested in research on its development and practical application.

Molten carbonates, alkaline solutions, solid polymers, solid oxides, etc. are mainly used for the electrolyte of the fuel cell, but recently, at a high temperature in order to promote the reaction by adopting phosphoric acid as the electrolyte. -The high temperature and high pressure phosphoric acid fuel cell that operates at high pressure is being developed as a typical fuel cell.

As described above, the fuel cell power plant is expected to be applied as a distributed power source especially in a large city area because it is clean energy. The fuel cell plant currently under study has an output of 5 MW to 11 MW.

On the other hand, what makes a fuel cell power plant possible as a plant for thermal power substitution in such a large urban area is the high output of the fuel cell main body in particular, and the development of high performance catalysts and large cells in recent years have become possible. This is because the output of 500 kW to 1000 kW per stack has become possible due to the development of manufacturing technology.

Still, about 10 stacks are required for each plant, and each fuel cell is connected in series or in parallel to obtain a high voltage. In this case, if a problem occurs even in one of the connected batteries, not only a predetermined output cannot be obtained, but also the entire plant may be stopped, resulting in a large loss. Therefore, high reliability is required for each stack of the fuel cell.

On the other hand, the phosphoric acid fuel cell uses phosphoric acid as an electrolyte, and in order to obtain high output of the cell, high temperature (about 200 ° C.) and high pressure (up to 9 kg / cm).
It is operated in ² ), in which case the battery body is used by being stored in a pressure vessel.

The structural parts or cells of the battery body are
They are forced to be used in very harsh conditions, which can cause problems with cells and structural components during operation. Therefore, while monitoring and designing the battery main body with high reliability, it is possible to diagnose the internal condition of the battery main body more accurately from the outside and to detect the damaged part early before serious damage occurs. Is desired.

In general, when a problem occurs in a single cell or a structure inside the fuel cell body, a symptom such as a decrease in fuel cell output or an increase in cell temperature often occurs. Therefore, as a method for directly diagnosing the internal state of the fuel cell body, a method of constantly monitoring the output voltage or temperature is effective, but in this case, it is necessary to take out a signal line from the pressure vessel to the outside.

FIG. 3 is a view showing the external appearance of a conventional high temperature and high pressure phosphoric acid fuel cell body. As shown in the figure,
The fuel cell is formed by stacking a plurality of unit cells 1 and cooling plates 2 and integrally fixing them by upper and lower tightening plates 3. The fuel cell stack 4 is inserted between the stack 4 and the tightening plate 3. It is composed of a spacer 5, a sealing material 6, a reaction gas supply / discharge manifold 7, and a connecting pipe 8 to the manifold 7.

Further, in order to monitor the output voltage or temperature of the fuel cell during power generation, it is "embedded in a cooling plate".
Alternatively, a terminal 9 for measuring the voltage or temperature, which is attached by "attaching to a cooling pipe arranged on a cooling plate with an attaching member", is attached.

From this measuring terminal 9, the output voltage between the sub-stacks (between cooling plates) is measured by a voltage measuring device outside the main body of the fuel cell to obtain the cell voltage in the sub-stack. The initial characteristics of the fuel cell at the time of shipment will be grasped and inspected.

FIG. 4 is a diagram showing a connection configuration between an external connection of a measuring instrument of a conventional fuel cell measuring apparatus and a voltage measuring line of a fuel cell. As shown in the figure, since the fuel cell main body is held in a closed pressure vessel 10 which is filled with an inert gas such as nitrogen in order to maintain airtightness, the fuel cell body is actually placed in a penetrating portion of the pressure vessel. The connector 11 is attached, and the cable connecting the external measurement line 12 to the voltage monitoring device on the outside of the pressure vessel and the voltage measurement line 13 of the fuel cell body is connected, so that the pressure vessel can be removed during maintenance of the fuel cell body. It has a structure that can be easily done.

The connector 11 comprises a receptacle 14 connected to the penetrating portion of the pressure vessel and a plug 15 connected to an external voltage measuring device. Receptacle 1
No. 4 is attached to the pressure vessel by an O-ring 16 from the inside of the pressure vessel and an attachment part 17 attached from the outside of the pressure vessel so as to keep the airtightness of the connection portion.

The plug 15 has a structure in which it is screwed into a joint portion with the receptacle 14 and is structured so as not to be accidentally detached. Plug 15 and receptacle 14
Has a pin contact, and an insulating rubber 1 is provided around each pin to maintain insulation between adjacent pins.
6 is mounted so as to fit around the receptacle and the pin on the plug side.

[0017]

By the way, the connector for connecting to the voltage measurement point of the fuel cell body constructed as described above has the receptacle 14 and the plug 15 of the connector 11 during long-term operation at the cell operating temperature. It is feared that the pin will have poor contact.

As described above, since the pressure vessel 10 is kept at high temperature (about 200 ° C.) and high pressure (about 9 kg / cm ² ) during power generation, the connector 11 arranged in the penetrating portion of the pressure vessel 10 is Used in harsh high temperature, high pressure and nitrogen gas atmosphere containing water vapor.

Further, when the fuel cell power generation is stopped, the temperature inside the pressure vessel of the cell body is lowered to room temperature, so that the connector 11 is exposed to the heat cycle due to the power generation stop of the fuel cell.

Further, since the connector 11 connects the inside and the outside of the pressure vessel 10, a force acts from the inside of the vessel on the high pressure side to the outside of the vessel at atmospheric pressure. Therefore, it was found that due to repeated heat cycles and an atmosphere containing water vapor, the insulating rubber that prevents the insulation resistance of the pins from deteriorating due to heat, peeling off and adhering to the surroundings, and degrading the rubber due to decomposition gas. ing.

Further, in such a connector structure, the signal lines are connected by contact between the pins. However, in a high temperature state of from room temperature to 200 ° C., there is a problem that poor contact between the plug 15 and the pin of the receptacle 14 is likely to occur due to thermal expansion of the pin and surrounding members.

That is, in order to be used in such a severe environment atmosphere, this connector is required to have high temperature, steam resistance and pressure resistance for its structural members, and to prevent contact failure due to thermal expansion. In addition, since the processing precision in manufacturing is also required to be very high, this connector becomes very expensive.

In addition, even in a connector in which no abnormality was recognized in the initial stage, a contact cycle between pins may occur due to a heat cycle due to long-term operation, which makes operation monitoring impossible.

As described above, in the conventional structure, due to the harsh environmental atmosphere of the mounting portion, deterioration of the insulator of the connector or poor contact between pins is likely to occur, and the electromotive reaction is smoothly promoted over a long period of time. There was a problem that it adversely affects the operation monitoring of the fuel cell body.

The present invention has been made in view of the above circumstances, and is assumed in a fuel cell operation for a long period of time.
It is possible to prevent the contact failure between the measurement line and the measurement line that measures the operating status such as the voltage or temperature of the battery main body and the measurement failure due to material deterioration, and to stably monitor the operating status of the fuel cell main body. An object of the present invention is to provide a fuel cell measuring device that can be used.

[0026]

Therefore, first, in order to achieve the above-mentioned object, the invention according to claim 1 is a fuel cell measuring apparatus for measuring an operating condition of a fuel cell main body housed in a pressure vessel with a measuring instrument. In, a measurement line attached to the opening provided in the pressure vessel, for transmitting the measurement result of the measurement means for measuring the operating condition of the fuel cell main body,
A through terminal that connects a relay wire that relays between the measurement wire and a measurement wire that transmits the measurement result to the measuring instrument so as to withstand the environmental atmosphere inside the pressure vessel, the relay wire and the measurement wire. And a connecting device for connecting to the outside of the pressure vessel.

The invention according to claim 2 is the fuel cell measuring device according to claim 1, wherein the through terminal is attached to an opening of the pressure vessel and is substantially circular on a bottom surface located outside the pressure vessel. A bottomed cylindrical mounting part having a hole formed therein, and an outer diameter that is arranged so as to penetrate through the hole formed on the bottom surface of the mounting part and that substantially matches the hole formed on the bottom surface of the mounting part. A metal fitting that is a cylinder having a male thread formed from a predetermined position on the surface to one end side and a flange for fixing to the bottom surface of the mounting component, and a male thread formed on the surface of the metal fitting. A nut for fixing the metal fitting and the mounting part by being screwed into the metal fitting, and arranged inside the metal fitting, one end side of which is connected to the measurement line by high temperature solder, and the other end side of which is connected by high temperature solder. A metallic pin is connected to the trunk line,
An insulating material for fixing the pin and a mold for sealing the joint between the pin and the measurement line and the joint between the pin and the relay line are provided inside the metal fitting.

Further, the invention according to claim 3 is the same as claim 2
In the fuel cell measuring device described above, an elastic member for maintaining airtightness of the pressure vessel is added between the flange of the metal fitting and the mounting component.

Further, the invention according to claim 4 is the invention according to claim 2.
In the fuel cell measuring apparatus described above, a waterproof metal fitting for protecting a mold outside the pressure vessel among the molds is added.

Further, the invention according to claim 5 is the same as claim 1.
In the fuel cell measuring device described above, the connecting device is a connector, and a receptacle of the connector on one end side of the relay wire is configured to have a size capable of passing through an opening of the pressure vessel. Is characterized by.

The invention according to claim 6 is the same as claim 1.
In the fuel cell measurement device described above, the connection device is configured by a terminal block that connects a terminal of the relay line to the measurement line.

The invention according to claim 1 is characterized by
The environment inside the pressure vessel includes a measuring line for transmitting the measurement result of the measuring means for measuring the operating condition of the fuel cell main body, and a relay line for relaying between the measuring line and the measuring line for transmitting the measurement result to the measuring instrument. Since the connection is made so as to withstand the atmosphere and the connecting device connects the relay line and the measurement line outside the pressure vessel, it is possible to prevent contact failure between the measurement line and the measurement line.

According to the second aspect of the present invention, one end of the metal pin is connected to the measurement line and the other end is connected to the relay line by the high temperature solder. However, there is no contact failure. Further, by integrating the joint portion between the pin and the connecting wire and the joint portion between the pin and the relay wire with a mold, it is possible to prevent a short circuit between the pins of the through terminal caused by water vapor and a dielectric breakdown.

According to a third aspect of the invention, in the fuel cell measuring device according to the second aspect, the pressure vessel can be kept airtight by adding an elastic member between the flange of the metal fitting and the mounting component.

The invention according to claim 4 can protect the mold in the fuel cell measuring device according to claim 2 by adding waterproof metal fittings. According to a fifth aspect of the present invention, in the fuel cell measuring apparatus according to the first aspect, the connecting device is a connector, and the receptacle of the connector on one end side of the relay wire can pass through the opening of the pressure vessel. Since it has a size, it is possible to remove the entire through terminal from the inside of the pressure vessel.

According to a sixth aspect of the present invention, in the fuel cell measuring device according to the first aspect, since the connecting device is composed of a terminal block that connects the terminals of the relay line to the measurement line, the terminal block is connected to the relay line. By removing the terminal of the above, it is possible to remove inside the pressure vessel together with the relay wire attached to the through terminal.

[0037]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> FIG. 1 is a diagram for explaining a connection configuration of a voltage measuring line of a fuel cell measuring apparatus according to a first embodiment of the present invention and a measuring line connected to a measuring device. (Embodiments corresponding to the inventions of claims 1 to 5). The same parts as those in FIGS. 3 and 4 are designated by the same reference numerals for description.

As shown in the figure, the penetration terminal 18 maintains the airtightness of the connection portion by the O-ring 16 from the inside of the pressure vessel 10 and the attachment part 17a of the penetration terminal 18 attached from the outside of the pressure vessel 10. Is attached to the pressure vessel 10.

The penetrating terminal 18 is integrated with a bottomed cylindrical mounting part 17a having a circular hole on the bottom surface by a mounting screw (nut) 17b. Then, inside the through terminal 18, an external measurement line (relay line) 12 connected to a voltage monitoring device outside the pressure vessel 10
Is connected to the voltage measuring line 13 of the fuel cell body.

The inside of the through terminal 18 is constructed as follows. The external measurement line 12a and the voltage measurement line 13 of the fuel cell body are covered with a heat resistant material, for example, a fluororesin, and the conductor is exposed only at a few millimeters of the tip for soldering. It is connected with high temperature solder.

The pin 23 is made of a metal such as copper and is fixed to the outside with an insulating material 24 that withstands high temperature and high pressure, for example, a cryoflex. In addition, the pin 23 and the external measurement line 12
a or pin 23 and soldering portion 25 of voltage measuring line 13
Are sealed by a mold 26.

The mold 26 is a cylinder having an outer shape that substantially matches the hole formed in the bottom surface of the mounting part 17a.
In addition, a male screw is formed from a predetermined position on the surface to one end side, and is fixed to a metal fitting 27 having a flange for fixing to the bottom surface of the mounting component 17a.
Further, the outer mold part of the pressure vessel 10 is protected by the waterproof metal fitting 28.

Further, in order to easily remove the pressure vessel during maintenance of the fuel cell main body, a removable connector 19 is provided in the middle of the cable 11 which is an external measurement line.
Need to go through.

The receptacle of the connector 19 is sized so as to pass from the outside to the inside of the opening 20 of the pressure vessel 10 so that the receptacle can be detached inside the pressure vessel 10.

Next, the operation of the fuel cell measuring device having the connection structure for the operation monitoring measuring lines of the present embodiment configured as described above will be described. In the measurement line connection structure of the fuel cell having such a structure, the environmental atmosphere of the penetrating portion 18 is the same as that of the conventional one, which is harsh in high temperature, high pressure, and steam atmosphere,
Since the external measurement line 12a, the voltage measurement line 13 and the pin 23 are connected by high temperature solder having a guaranteed heat resistance of 230 to 250 ° C., no contact failure occurs.

Further, the through terminal 18 and the external measuring wire 12a
It is also possible to prevent a short circuit or a dielectric breakdown between the pins 23 of the through terminal, which is caused by water vapor, by having the structure in which the connection portion with and the connection portion with the high temperature solder are integrated with the mold 26.

On the other hand, the connector 19 serving as a detaching portion is
Since it is located outside the pressure vessel 10 and is under atmospheric pressure and normal temperature conditions, contact failure between pins 23 or deterioration of material does not occur even during repeated heat cycles.

Therefore, according to the fuel cell measuring apparatus of this embodiment, it is possible to monitor the operating condition of the fuel cell while maintaining high reliability even during long-term operation. <Second Embodiment> FIG. 2 is a diagram showing the configuration of a fuel cell measuring apparatus according to a second embodiment of the present invention (an embodiment corresponding to the invention of claim 6). The same parts as those in FIG. 1 will be described with the same reference numerals.

A feature of the fuel cell measuring device according to the present embodiment is that, as shown in FIG. 2, the connection between the external measuring line 12a and the external measuring line 12b is made by the terminal box 21.

That is, at the time of detaching from the pressure vessel 10, the terminal 22 connected to the terminal box 21 is removed, and the opening 20 opened in the pressure vessel 10 for connecting the mounting component 17 is connected to the outside of the pressure vessel. The penetrating terminal 18 is removed by passing it through the inside.

Next, the operation of the fuel cell measuring device according to this embodiment having the above-mentioned structure will be described. In the present embodiment, as shown in FIG. 2, the environment atmosphere of the penetrating portion 18 is the same as the conventional one, that is, high temperature, high pressure, and water vapor atmosphere are harsh as in the conventional embodiment, but the measurement line 12a, the pin 23, and The measurement line 13 and the pin 23 are connected by high temperature solder having a guaranteed heat resistance temperature of 230 to 250 ° C., so that no contact failure occurs.

On the other hand, since the terminal box 21 serving as a detaching portion is located outside the pressure vessel 10 and is in an atmospheric pressure condition and a room temperature condition, even if repeated heat cycles occur, the space between the connector pins as generated in the connector structure is increased. It does not cause poor contact or poor measurement due to material deterioration.

Therefore, it is possible to obtain a fuel cell capable of performing operation monitoring while maintaining high reliability even during long-term operation. Further, since the removable portion is a small terminal to be attached to the terminal box 21, the size of the penetrating terminal 18 is not restricted as much as in the first embodiment.

Therefore, according to the fuel cell measuring apparatus according to the present embodiment, it is possible to prevent the contact failure at the connecting portion as in the case of the above-mentioned first embodiment, and it is high even during long-time operation. The operation of the fuel cell can be monitored while maintaining reliability.

[0055]

As described above in detail, according to the present invention,
Prevents contact failures and measurement failures due to material deterioration that occur between the measurement line and the measurement line that measures the operating conditions such as the voltage or temperature of the battery itself, which is expected in long-term fuel cell operation It is possible to provide a fuel cell measuring device capable of monitoring the operating state of the fuel cell body.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a connection configuration between a voltage measuring line and a measuring line connected to a measuring device of a fuel cell measuring device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a fuel cell measuring device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing an external configuration of a conventional high-temperature high-pressure phosphoric acid fuel cell body.

FIG. 4 is a diagram showing a connection configuration between an external connection of a measuring instrument of a conventional fuel cell measuring device and a voltage measuring line of a fuel cell.

[Explanation of symbols]

1 ... Unit cell, 2 ... Cooling plate, 3 ... Upper / lower clamping plate, 4
... Fuel cell stack, 5 ... Spacer, 6 ... Sealing material, 7 ...
Manifold, 8 ... Connection pipe, 9 ... Measurement terminal, 10 ... Sealed pressure vessel, 11 ... Connector, 12a, 12b ... External measurement line, 13 ... Voltage measurement line, 14 ... Receptacle, 15 ...
Plug, 16 ... O-ring, 17 ... Mounting part, 18 ... Penetration terminal, 19 ... Connector, 20 ... Opening part, 21 ... Terminal box,
22 ... Terminal, 23 ... Pin, 24 ... Insulation material, 25 ... Soldering part, 26 ... Mold, 27 ... Metal fitting, 28 ... Waterproof metal fitting.

Claims (6)

[Claims] 1. A fuel cell measuring device for measuring an operating condition of a fuel cell main body housed in a pressure container with a measuring instrument, the operating condition of the fuel cell main body being attached to an opening provided in the pressure container. A measuring line for transmitting the measurement result of the measuring means for measuring, and a relay line for relaying between the measuring line and the measuring line for transmitting the measurement result to the measuring device, so that the environmental atmosphere inside the pressure vessel can be endured. A fuel cell measuring device comprising: a through terminal to be connected, and a connecting device for connecting the relay wire and the measuring wire outside the pressure vessel. 2. The through-hole terminal is attached to an opening of the pressure vessel, and has a bottomed cylindrical attachment part having a substantially circular hole on a bottom surface located outside the pressure vessel, and the attachment part. Is a cylinder that is arranged so as to penetrate through a hole formed in the bottom surface of the mounting part and has an outer diameter that substantially matches the hole formed in the bottom surface of the mounting part, and a male screw is formed from a predetermined position on the surface to one end side. A metal fitting formed with a flange for fixing to the bottom surface of the fitting, and a nut fixing the fitting and the fitting by being screwed into a male screw formed on the surface of the fitting, A metal pin arranged inside the metal fitting, one end side of which is connected to the measurement line by high-temperature solder and the other end side of which is connected to the relay wire by high-temperature solder, and which is arranged inside the metal fitting. An insulating material for fixing the pin, the pin and the measuring line and a fuel cell measuring apparatus according to claim 1, characterized by including a mold for sealing the connecting portion between the pin and the relay line. 3. The fuel cell measuring device according to claim 2, wherein an elastic member for keeping airtightness of the pressure vessel is added between the flange of the metal fitting and the mounting component. 4. The fuel cell measuring device according to claim 2, further comprising a waterproof metal fitting for protecting a mold outside the pressure vessel among the molds. 5. The connection device is a connector, and the receptacle of the connector on one end side of the relay line is:
The fuel cell measuring device according to claim 1, wherein the fuel cell measuring device has a size capable of passing through an opening of the pressure container. 6. The fuel cell measuring device according to claim 1, wherein the connection device is composed of a terminal block that connects a terminal of the relay line to the measurement line.