JP2002117877A - Solid polymer fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid polymer fuel cell system which collects thermal energy which are radiating heat at the start-up, while realizing more stabilized water recovery and safe driving. SOLUTION: The system is constituted with a fuel generation means, the solid polymer fuel cell, a fuel gas supply flow path, a fuel gas exhaust flow path, a bypass flow path which connects the above fuel gas supply flow path with the above fuel gas exhaust flow path, and fuel side condensation means which make steam condense by cooling the exhausted fuel gas which is exhausted from the fuel cell or the fuel gas passed through the above bypass. Further, a fuel side bypass condensation means, which cools the fuel gas and carries out steam condensation, is equipped in the above by pass way or in the fuel gas exhaust flow way between the above bypass and the above fuel side condensation means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer electrolyte fuel cell system for generating electric power using a polymer electrolyte fuel cell.

[0002]

2. Description of the Related Art A conventional polymer electrolyte fuel cell system will be described with reference to the drawings.

As shown in FIG. 7, a conventional polymer electrolyte fuel cell system includes a fuel cell 1 for generating power using a fuel gas and an oxidizing gas, a fuel gas supply / discharge system, and a supply of an oxidizing gas. It has a discharge system and a cooling system for the fuel cell 1.

First, a fuel gas supply / discharge system will be described. The fuel gas supply side includes a fuel gas generator 2 that steam-reforms a raw material gas such as natural gas to generate a hydrogen-rich fuel gas, and a fuel-side humidifier 3 that humidifies the fuel gas. On the fuel gas discharge side, a fuel-side condenser 4 for cooling the residual fuel gas discharged from the fuel cell 1 and condensing the contained water vapor, and a combustor for burning the combustion gas such as natural gas and the residual fuel gas 5 and an air supply device 6 for supplying air for combustion. Furthermore, a bypass path 7 for bypassing the fuel cell 1 and a fuel gas flow path
Or a fuel gas flow path switching valve 8 that can be switched to the bypass path 7.

Next, a description will be given of a supply / discharge system for air, which is an oxidizing gas. The air supply / discharge system includes an air supply device 9 for supplying oxidant air to the fuel cell 1, an air-side humidifier 10 for humidifying the supply air, and steam contained in the air discharged from the fuel cell 1 for cooling. And an air-side condenser 11 for condensing air. A condensed water tank 12 for storing water condensed by the fuel-side condenser 4 and the air-side condenser 11;
A fuel-side water pump 13 for sending condensed water to the fuel-side humidifier 3 and an air-side water pump 14 for sending to the air-side humidifier 10 are provided.

On the other hand, in the cooling system of the fuel cell 1, the fuel cell 1
And cooling pump 15 for circulating water in the cooling pipe
And a cooling radiator 16 for releasing heat generated in the fuel cell 1 to the outside.

The fuel gas generated by the fuel gas generator 2 contains water vapor, carbon dioxide, and a trace amount of carbon monoxide in addition to hydrogen. This fuel gas is humidified by the fuel-side humidifier 3 using water supplied from the condensed water tank 12 by the fuel-side water pump 13. The humidified fuel gas is sent to the fuel-side condenser 4 via the bypass path 7 by the fuel gas flow path switching valve 8 when the fuel gas contains a large amount of carbon monoxide at the time of starting the system or the like. Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the fuel gas is supplied to the fuel cell 1 by the fuel gas flow path switching valve 8 to generate power.

In the polymer electrolyte fuel cell system, the fuel cell 1 is 80 times smaller than in the case of the phosphoric acid type (about 200 ° C.).
It operates at a very low temperature of about ° C. Therefore, in the phosphoric acid type fuel cell, there is no problem even if the fuel gas containing several% of carbon monoxide is supplied to the fuel cell 1, but in the polymer electrolyte fuel cell, carbon monoxide is supplied at a rate of several tens ppm or more. When the fuel gas containing the fuel gas is supplied to the fuel cell 1, the catalyst in the fuel cell 1 is poisoned and the power generation performance is deteriorated.

After the fuel gas is burned in the fuel cell 1, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged from the fuel cell 1 as a residual fuel gas. The discharged residual fuel gas is cooled by the fuel-side condenser 4 and the water vapor is removed (dehumidified).
It is supplied to the combustor 5. In the combustor 5, the combustion gas such as natural gas and the residual fuel gas are burned, and the temperature of the fuel gas generator 2 is maintained at about 700 ° C. This temperature is a temperature required to generate a hydrogen-rich fuel gas from the source gas.

Similarly, the fuel gas that has passed through the bypass path 7 by the fuel gas flow path switching valve 8 at the time of startup is also supplied to the combustor 5 after being dehumidified by the fuel-side condenser 4, and is supplied together with the combustion gas or the fuel gas. Burned with gas only.

Next, a supply / discharge system for air, which is an oxidizing gas, will be described. The air is sent to the air-side humidifier 10 by the air supply device 9, humidified using water supplied from the condensed water tank 12 by the air-side water pump 14, and sent to the fuel cell 1. The air discharged from the fuel cell 1 and not used for power generation is supplied to the air-side condenser 1.
After cooling and removal of water vapor (dehumidification) by 1, it is released to the atmosphere.

Further, in order to keep the temperature of the fuel cell 1 for generating electricity constant, a cooling pump 15
Circulates water, and the heat generated in the fuel cell 1 is released to the outside by the cooling radiator 16.

Further, the fuel-side condenser 4 and the air-side condenser 11
The dehumidified water is stored in the condensed water tank 12 and supplied to the fuel humidifier 3 and the air humidifier 10 as humidified water by the fuel water pump 13 and the air water pump 14, respectively. At times, it may be supplied to the fuel gas generator 2 as water for steam reforming.

[0014]

In the prior art, at the time of startup, all the fuel gas exiting the fuel-side humidifier 3 passes through the bypass path 7 by the fuel gas flow path switching valve 8 and then to the fuel-side condenser. 4 to be dehumidified.

Here, it is assumed that the fuel gas during startup and the remaining fuel gas during power generation are cooled to about 40 ° C. in the fuel-side condenser 4. The amount of heat radiation in the fuel-side condenser 4 when operating the polymer electrolyte fuel cell system is about 120 W when performing the 1.5 kW AC power generation operation and about 900 W when performing the start-up operation. It is.
Therefore, it is necessary for the fuel-side condenser 4 to dissipate a calorific value of about 7 times the calorific value difference. In designing the fuel-side condenser 4, when the optimum design is performed at the rated operation, fuel gas far exceeding the designed amount flows into the fuel-side condenser 4 at the time of startup, so that the capacity of the fuel-side condenser 4 becomes insufficient. . As a result, the amount of water that can be recovered by the fuel-side condenser 4 decreases.

Since no water generation reaction occurs at the time of startup, the amount of water in the condensed water tank 12 decreases in total. That is, at this time, particularly when the water in the condensed water tank 12 is used as the water for steam reforming, water in the fuel cell system decreases more rapidly, and stable operation of the fuel cell system becomes impossible. .

Further, when designing the fuel-side condenser 4 so as to be optimal at the time of start-up, the design becomes excessively large at the time of rated operation, and the design cost due to an increase in pressure loss in the flow path of the fuel-side condenser 4 or an increase in the capacity of the cooling fan. It increases the power consumption and the system power consumption.

Further, the temperature of the fuel gas at the outlet of the fuel-side humidifier 3 is about 150 ° C., but the service temperature of the fuel gas passage switching valve 8 is almost 100 ° C. or less. In the configuration, the failure due to the temperature deterioration of the fuel gas flow path switching valve 8 occurs.

In addition, most of the heat energy of the fuel gas at the time of start-up is discarded into the atmosphere by heat radiation in the fuel-side condenser 4.

Accordingly, the present invention provides a polymer electrolyte fuel cell system capable of realizing more stable water recovery and safe operation in consideration of the above-mentioned problems of the conventional polymer electrolyte fuel cell system. It is intended to do so. Further, the present invention provides a polymer electrolyte fuel cell system capable of realizing recovery of heat energy radiated during startup.

[0021]

Means for Solving the Problems The present invention provides at least:
A fuel generating means for reforming a source gas to generate a hydrogen-rich fuel gas; a polymer electrolyte fuel cell for generating power using a fuel gas and an oxidizing gas; and an inlet / outlet of the fuel cell in a fuel gas flow path And a fuel-side condensing means for cooling the exhaust gas discharged from the fuel cell or the fuel gas discharged from the bypass path and condensing the contained water vapor.The bypass path cools the fuel gas. A polymer electrolyte fuel cell system comprising a fuel-side bypass path condensing means for condensing water vapor. Further, it is more effective to have a fuel gas passage opening / closing means and a fuel gas passage switching means.

Further, in the polymer electrolyte fuel cell system according to the present invention, the fuel-side bypass-path condensing means is a cooling means for exchanging heat with the heat transport medium, and the fuel-side bypass-path condensing means recovers the fuel into the heat transport medium. A heat storage means for storing the waste heat to be generated.

Further, in the polymer electrolyte fuel cell system of the present invention, the exhaust heat is recovered by performing cooling by heat exchange with the heat transport medium using the fuel-side bypass path condensing means. To raise the temperature of the fuel cell.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 1 of the present invention. The polymer electrolyte fuel cell system according to the present embodiment includes a fuel cell 21 that generates power using a fuel gas and an oxidant gas, a fuel gas supply / discharge system, an oxidant gas supply / discharge system, and a fuel cell 21. Cooling system.

On the supply side of the fuel gas supply / discharge system, a fuel gas generator 22 for reforming a raw material gas such as natural gas by steam to generate a hydrogen-rich fuel gas, and a fuel-side humidifier 23 for humidifying the fuel gas And On the discharge side, a fuel-side condenser 24 for cooling the residual fuel gas discharged from the fuel cell 21 and condensing the contained water vapor, a combustor 25 for burning a combustion gas such as natural gas and the residual fuel gas, An air supply device 26 for supplying air for combustion is provided. Further, a bypass path 27 for bypassing the fuel cell 21;
A fuel-side bypass path condenser 28 for cooling the fuel gas flowing through the bypass and condensing the water vapor contained therein, and a fuel gas flow path switching valve 29 capable of switching the flow path of the fuel gas to the fuel cell 21 or the bypass path 27. Prepare.

The air supply / discharge system includes an air supply device 30 for supplying oxidant air to the fuel cell 21, an air humidifier 31 for humidifying the supply air, and cooling the air discharged from the fuel cell 21. An air-side condenser 32 for condensing the contained water vapor is provided. A condensed water tank 33 for storing water condensed by the fuel-side condenser 24 and the air-side condenser 32;
A fuel-side water pump 34 for sending condensed water to the fuel-side humidifier 23 and an air-side water pump 35 for sending to the air-side humidifier 31 are provided.

On the other hand, in the cooling system of the fuel cell 21, a cooling pump 3 for circulating water in the fuel cell 21 and the cooling pipe is provided.
6 and a cooling radiator 37 for releasing heat generated in the fuel cell 21 to the outside.

Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.

In the fuel gas generator 22, the combustor 25 is heated to a temperature of about 700 ° C. in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as natural gas. . At the same time, the fuel gas generator 22 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 21. The fuel gas discharged from the fuel gas generator 22 is humidified by the fuel humidifier 23 using water supplied from a condensed water tank 33 by a fuel water pump 34.

When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the fuel gas flow path switching valve 29 closes the fuel cell 21 and opens the bypass path 27. At this time, the humidified fuel gas is guided to the bypass path 27 by the fuel gas flow path switching valve 29, is cooled by the fuel-side bypass path condenser 28, and dehumidifies the contained steam. The cooled and dehumidified fuel gas is sent to the fuel-side condenser 24. The fuel gas is further cooled by the fuel-side condenser 24 to dehumidify the contained water vapor, and then supplied to the combustor 25, where it is burned together with the combustion gas or only with the fuel gas.

Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the fuel gas flow path switching valve 29 opens the fuel cell 21 and closes the bypass path 27. The humidified fuel gas is supplied to the fuel cell 2 by the fuel gas passage switching valve 29.
1 to generate electricity. From the fuel cell 21, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged residual fuel gas is cooled by the fuel-side condenser 24 to dehumidify the contained water vapor, and then supplied to the combustor 25, where it is burned together with the combustion gas or only with the residual fuel gas. The water condensed in the fuel-side bypass path condenser 28 and the fuel-side condenser 24 is stored in the condensed water tank 33.

The air as the oxidizing gas is fed into the air-side humidifier 31 by the air supply device 30, humidified using water supplied from the condensed water tank 33 by the air-side water pump 35, and supplied to the fuel cell 21. Sent in. The air not used for power generation discharged from the fuel cell 21 contains water generated by power generation in the fuel cell 21 and is discharged in a highly humidified state. The air discharged from the fuel cell 21 is discharged to the atmosphere after being cooled by the air-side condenser 32 to dehumidify the contained water vapor. In addition, the air-side condenser 3
The water condensed in 2 is stored in the condensed water tank 33.

Further, in order to keep the temperature of the fuel cell 21 for generating electricity constant, a cooling pump 3
Water is circulated in 6, and the heat generated in the fuel cell 21 is released to the outside by the cooling radiator 37.

With the configuration of the polymer electrolyte fuel cell system according to the present embodiment, the fuel-side condenser 24 can be optimally designed at rated operation. When the fuel gas passes through the bypass path 27 by the fuel gas flow path switching valve 29 at the time of start-up or the like, the insufficient condensation capacity of the fuel-side condenser 24 can be compensated for by the fuel-side bypass path section condenser 28. is there. Conversely, the bypass path condenser 28
May be designed so as to make up for the insufficient capacity of the fuel-side condenser 24.

As a result, it is possible to easily solve the problems of an excessive design of the fuel-side condenser 24 and an increase in design cost and an increase in system power consumption due to an increase in pressure loss or an increase in cooling fan capacity.

Further, since the condensing ability of the fuel gas supply / discharge system at the time of startup can be improved, a more stable operation of the polymer electrolyte fuel cell system can be realized by increasing the amount of water recovered at the time of startup.

As shown in FIG. 2, in the configuration of the polymer electrolyte fuel cell system according to the present embodiment, the bypass passage of the fuel gas discharge side flow path between the fuel cell 21 and the fuel side condenser 24 is provided. At a position upstream of the junction with 27,
By using the fuel gas passage opening / closing valve 38, it is possible to prevent water or fuel gas condensed in the fuel-side bypass passage portion condenser 28 from flowing into the fuel cell 21 at the time of startup. Accordingly, it is possible to prevent the inside of the fuel cell 21 or the fuel gas flow path from being blocked by the condensed water, and further to prevent the fuel cell 21 from being poisoned by the high carbon monoxide-containing fuel gas at the time of startup. Therefore, a polymer electrolyte fuel cell system with improved reliability can be realized.

(Embodiment 2) FIG. 3 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 2 of the present invention. However, components having the same members and the same functions as those in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted.

The fuel gas flow switching valve 29 shown in FIG. 1 is not provided on the supply side of the fuel gas supply / discharge system. Instead, by providing the fuel gas flow path switching valve 39 at the junction of the fuel gas exhaust flow path from the fuel cell 1 and the bypass path 27, the inflow path to the fuel-side condenser 24 is changed to the fuel cell 21
Or from the bypass path 27.

With this configuration, when the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the fuel gas flow path switching valve 39 closes the direction from the fuel cell 21 and opens the direction from the bypass path 27. And At this time, the humidified fuel gas is guided to the bypass path 27 along the flow path formed by the fuel gas flow path switching valve 39, cooled by the fuel-side bypass path condenser 28, and dehumidified. The cooled and dehumidified fuel gas is sent to the fuel-side condenser 24. After the fuel gas is further cooled and dehumidified by the fuel-side condenser 24, the fuel gas is supplied to the combustor 25, and is burned together with the combustion gas or only with the fuel gas.

Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the fuel gas passage switching valve 39 opens the direction from the fuel cell 21 and closes the direction from the bypass path 27.
The humidified fuel gas is supplied to the fuel cell 21 along the flow path formed by the fuel gas flow path switching valve 39 to generate power. From the fuel cell 21, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged residual fuel gas is cooled by the fuel-side condenser 24 to dehumidify the contained water vapor, and then supplied to the combustor 25, where it is burned together with the combustion gas or only with the residual fuel gas. The water condensed in the fuel-side bypass path condenser 28 and the fuel-side condenser 24 is stored in the condensed water tank 33.

In the above configuration, together with the operation shown in the first embodiment, the fuel gas flow path switching valve 3
The temperature of the fuel gas flowing into the fuel cell 9 can be reduced. As a result, the operating environment conditions of the fuel gas switching valve 39 can be further relaxed, the life of the fuel gas switching valve 39 can be extended, and the operation of the polymer electrolyte fuel cell system that can realize safer operation can be realized. Can be realized.

As shown in FIG. 4, in the configuration of the polymer electrolyte fuel cell system in the present embodiment, the bypass passage 27 of the fuel gas supply passage between the fuel humidifier 23 and the fuel cell 21 is provided. By using the fuel gas passage opening / closing valve 40 at a position downstream of the branch to the fuel cell, it is possible to prevent the fuel gas from flowing into the fuel cell 21 at startup. This can prevent the fuel cell 21 from being poisoned by the high carbon monoxide-containing fuel gas at the time of startup. That is, a polymer electrolyte fuel cell system with improved reliability can be realized.

(Embodiment 3) FIG. 5 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 3 of the present invention. However, components having the same members and functions as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

The fuel gas supply / discharge system is provided with a fuel-side bypass path condenser 41 for cooling the fuel gas by heat exchange with water and condensing the contained steam. Further, waste heat recovered by heat exchange in the fuel-side bypass path condenser 41 is
Regenerator 42 that stores water as warm water by raising the temperature of the water
Is provided.

When the fuel gas contains a large amount of carbon monoxide at the time of starting the system or the like, the fuel gas flow path switching valve 29 closes the fuel cell 21 and opens the bypass path 27. At this time, the humidified fuel gas is guided to the bypass path 27 by the fuel gas flow path switching valve 29, and is cooled by heat exchange with water in the fuel-side bypass path condenser 41,
Dehumidified. The cooled and dehumidified fuel gas is sent to the fuel-side condenser 24. On the other hand, the water that has flowed out of the regenerator 42 is heated by the heat exchange with the fuel gas in the fuel-side bypass-path condenser 41 to become hot water and discharged from the fuel-side bypass-path condenser 41. The discharged hot water is stored in the regenerator 4
The hot water is stored in hot water 2 and is used as needed for a heat source such as hot water supply or a heater through a heat utilization device (not shown) as needed.

With the configuration of the polymer electrolyte fuel cell system according to the present embodiment, even when the fuel gas contains a large amount of carbon monoxide at the time of starting the system or the like,
Exhaust heat can be recovered from the high-temperature fuel gas, and the recovered exhaust heat can be stored. The recovered waste heat here is the heat that has been radiated to the atmosphere in the conventional example. Therefore, the polymer electrolyte fuel cell system according to the present embodiment can recover the heat energy that has been radiated at the time of startup.

Although the present embodiment has been described by showing a configuration obtained by developing FIG. 2, similar effects can be obtained in the configuration diagrams shown in FIGS. 1, 3 and 4.

(Embodiment 4) FIG. 6 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 4 of the present invention. However, components having the same members and functions as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

The fuel gas supply / discharge system is provided with a fuel-side bypass path condenser 41 for cooling the fuel gas by heat exchange with cooling water and condensing the contained steam. Further, the fuel cell 21
Is provided with a cooling water circulation path switching valve 43 for switching the cooling water circulation path between the cooling radiator 37 side and the fuel-side bypass path condenser 41 side.

When the fuel gas contains a large amount of carbon monoxide and the temperature of the fuel cell 1 is low, for example, when the system is started, the fuel gas flow path switching valve 29 closes the fuel cell 21 and opens the bypass path 27. And Also, the cooling water circulation path switching valve 43
, The cooling radiator 37 side is closed and the fuel-side bypass path part condenser 41 side is opened. At this time, the humidified fuel gas is supplied to the bypass passage 27 by the fuel gas passage switching valve 29.
And cooled by the heat exchange with the low-temperature cooling water in the fuel-side bypass path condenser 41 to be dehumidified. The cooled and dehumidified fuel gas is sent to the fuel-side condenser 24. On the other hand, the temperature of the cooling water is increased by heat exchange with the fuel gas in the condenser 41 on the fuel side bypass path. The heated cooling water is supplied to the fuel cell 1 by operating the cooling pump 36.
And heat exchange with the fuel cell 1 to raise the temperature of the fuel cell 1. The cooling water that has radiated heat by heat exchange with the fuel cell 1 returns to the fuel-side bypass-path condenser 41 again.

With the configuration of the polymer electrolyte fuel cell system according to the present embodiment, when the temperature of the fuel cell 1 is low, such as when the system is started, the temperature of the fuel cell 1 can be easily increased. Therefore, there is no need to provide a heater (not shown) for raising the temperature of the fuel cell 1. Moreover, in the present embodiment, the heat for raising the temperature of the fuel cell 1 is:
Conventionally, it is waste heat that has been radiated to the atmosphere. That is, the polymer electrolyte fuel cell system according to the present embodiment includes:
It is possible to realize the recovery of the heat energy which has been radiated at the time of startup, to realize a reduction in cost by not requiring a heater for raising the temperature of the fuel cell 1, and to reduce the power consumption at the time of startup.

Although the present embodiment has been described by showing a configuration obtained by developing FIG. 2, similar effects can be obtained in the configuration diagrams shown in FIGS. 1, 3 and 4.

[0055]

As is apparent from the above, the present invention has provided a polymer electrolyte fuel cell system capable of realizing more stable water recovery and safe operation. Further, a polymer electrolyte fuel cell system capable of recovering thermal energy radiated at the time of startup can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 1.

FIG. 2 is a configuration diagram showing a more preferable polymer electrolyte fuel cell system according to the first embodiment;

FIG. 3 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 2.

FIG. 4 is a configuration diagram showing a more preferable polymer electrolyte fuel cell system according to the second embodiment;

FIG. 5 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 3.

FIG. 6 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 4.

FIG. 7 is a configuration diagram showing a conventional polymer electrolyte fuel cell system.

[Explanation of symbols]

 1,21 fuel cell 2,22 fuel gas generator 3,23 fuel side humidifier 4,24 fuel side condenser 5,25 combustor 6,26 air supply 7,27 bypass path 8,29,39 fuel gas flow Route switching valve 9,30 Air supply device 10,31 Air side humidifier 11,32 Air side condenser 12,33 Condensed water tank 13,34 Fuel side water pump 14,35 Air side water pump 15,36 Cooling pump 16 , 37 Cooling radiators 28, 41 Fuel-side bypass path condenser 38, 40 Fuel gas flow path opening / closing valve 42 Heat storage unit 43 Cooling water circulation path switching valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01M 8/10 H01M 8/10

Claims (6)

[Claims] 1. A fuel generating means for reforming a raw material gas to generate a hydrogen-rich fuel gas, a polymer electrolyte fuel cell for generating electric power by using the fuel gas and an oxidizing gas, A fuel gas supply passage for supplying a fuel gas from the means to the fuel cell, a fuel gas exhaust passage for transporting the gas discharged from the fuel cell to the fuel generation means, the fuel gas supply passage and the fuel A bypass path connecting the gas exhaust flow path, and cooling an exhaust fuel gas discharged from the fuel cell or a fuel gas passing through the bypass path,
A fuel-side condensing means for condensing water vapor, in the bypass path, or in a fuel gas exhaust flow path between the position where the bypass path joins the fuel gas exhaust flow path and the fuel-side condensing means. A polymer electrolyte fuel cell system comprising a fuel-side bypass path condensing means for cooling the fuel gas and condensing water vapor. 2. The solid according to claim 1, further comprising a fuel gas passage opening / closing means in the fuel gas exhaust passage at a position upstream of a position where the fuel gas exhaust passage and the bypass passage meet. Polymer fuel cell system. 3. The fuel-side bypass path section condensing means,
2. The polymer electrolyte fuel cell system according to claim 1, wherein the fuel gas flow path switching unit is provided in the bypass path at a position where the fuel gas exhaust flow path and the bypass path join. 4. The solid according to claim 3, wherein a fuel gas passage opening / closing means is provided in the fuel gas supply passage at a position downstream of a position where the fuel gas supply passage and the bypass passage branch off. Polymer fuel cell system. 5. The fuel-side bypass path section condensing means,
The heat storage means for recovering heat of the gas passing through the condensing means on the fuel side bypass path by heat exchange with a heat transport medium, and further comprising heat storage means for storing the recovered heat. Or a polymer electrolyte fuel cell system according to any one of the above. 6. The fuel-side bypass path section condensing means,
The heat of the gas passing through the fuel-side bypass path condensing means is recovered by heat exchange with a heat transport medium, and the fuel cell is heated using the recovered heat. The polymer electrolyte fuel cell system according to any one of the above.