JP2000340241A - Solid polymer fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove water generated in a cathode and to resupply water necessary to an anode in a solid polymer fuel cell. SOLUTION: The pressure of air supplied to a cathode side of a solid polymer fuel cell as an oxygen containing gas is higher than that of hydrogen containing gas supplied to an anode side. The water generated at the cathode penetrates an electrolytic film toward the anode side by the pressure difference between the air and the hydrogen containing gas. A part of the water is used when a proton generated in the anode moves as a hydrate to the cathode side in the electrolyte. As a result, the water generated in the cathode is removed continuously, and the water necessary to the anode is continuously resupplied for efficiently operating the fuel cell continuously.

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, and more particularly to a polymer electrolyte fuel cell in which an electrolyte membrane formed of a polymer is sandwiched between two electrodes.

[0002]

2. Description of the Related Art In a polymer electrolyte fuel cell, a hydrogen-containing gas containing hydrogen and an oxygen-containing gas containing oxygen are supplied and subjected to an electrode reaction represented by the following equations (1) and (2). It converts chemical energy directly into electrical energy. In order for this electrode reaction to be continuously and smoothly performed, hydrogen must be continuously supplied to the catalyst at the anode, and protons generated must be promptly moved through the electrolyte membrane to the cathode side as hydrates. On the other hand, at the cathode, since oxygen is continuously supplied to the catalyst, it is necessary to continuously remove generated water which hinders the supply.

Anode reaction H ₂ → 2H ⁺ + 2e ⁻ (1) Cathode reaction 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O (2)

As a polymer electrolyte fuel cell that eliminates water generated at the cathode, one that maintains the water vapor pressure in the hydrogen-containing gas at the anode lower than the saturated water vapor pressure has been proposed (for example, Japanese Patent No. 2703824). Issue). In this polymer electrolyte fuel cell, by maintaining the water vapor pressure in the hydrogen-containing gas at the anode lower than the saturated water vapor pressure, the water produced by the electrochemical reaction at the cathode to which the oxygen-containing gas is supplied is subjected to the concentration gradient. While passing through the electrolyte membrane and removing from the cathode side,
It is said that a part of necessary water can be supplied on the anode side.

[0005]

However, in such a polymer electrolyte fuel cell, the water produced at the cathode may not be sufficiently eliminated. Even if the concentration gradient is generated by lowering the water vapor pressure in the hydrogen-containing gas on the anode side, the movement speed of water in the electrolyte membrane based on the concentration gradient is not fast enough to continuously eliminate all the water generated at the cathode. As a result, water stays at the cathode, and the adverse effect caused by the water staying, that is, inhibition of continuous supply of oxygen to the catalyst at the cathode occurs.

An object of the polymer electrolyte fuel cell of the present invention is to continuously eliminate water generated at a cathode. Another object of the polymer electrolyte fuel cell of the present invention is to supplement at least a part of water required at the anode with water generated at the cathode.

[0007]

Means for Solving the Problems and Their Functions and Effects The polymer electrolyte fuel cell of the present invention employs the following means to achieve at least a part of the above objects.

The polymer electrolyte fuel cell of the present invention is a polymer electrolyte fuel cell in which an electrolyte membrane formed of a solid polymer is sandwiched between two electrodes, and a hydrogen electrode is provided on one electrode of the electrolyte membrane. A hydrogen-containing gas supply unit for supplying a hydrogen-containing gas containing oxygen, and an oxygen-containing gas supply for supplying an oxygen-containing gas containing oxygen at a pressure higher than the supply pressure of the hydrogen-containing gas to the other electrode of the electrolyte membrane. And a means.

In the polymer electrolyte fuel cell according to the present invention,
Supplying an oxygen-containing gas containing oxygen to the other electrode (cathode) of the electrolyte membrane at a pressure higher than the supply pressure of the hydrogen-containing gas supplied to one electrode (anode) of the electrolyte membrane; As a result, generated water generated on the cathode side of the electrolyte membrane is eliminated to the anode side with a pressure difference, and necessary water is supplemented on the anode side. As a result, continuous supply of oxygen to the catalyst at the cathode can be ensured, and continuous rapid movement of protons at the electrolyte membrane can be ensured, whereby a high-performance fuel cell can be obtained.

In the polymer electrolyte fuel cell according to the present invention, the fuel cell may be provided with reinforcing means disposed inside and / or on the surface of the electrolyte membrane to reinforce the strength of the electrolyte membrane. In this way, the load on the electrolyte membrane caused by the pressure difference can be reduced, and damage to the electrolyte membrane can be prevented. In the polymer electrolyte fuel cell according to the aspect of the present invention, the reinforcing means may be reinforced by changing a degree of reinforcement of each part of the electrolyte membrane according to a pressure difference between the hydrogen-containing gas and the oxygen-containing gas. May be used. In this case, necessary reinforcement can be performed at a necessary portion.

Further, in the polymer electrolyte fuel cell according to the present invention, the oxygen-containing gas supply means is configured to reduce a deviation of a pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane. The means for supplying the oxygen-containing gas to the other electrode may be used. In this case, since the pressure difference in each part of the electrolyte membrane becomes substantially equal, it is possible to prevent partial deterioration of the durability of the electrolyte membrane.

Further, in the polymer electrolyte fuel cell according to the present invention, the oxygen-containing gas supply means is configured to increase a deviation of a pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane. The means for supplying the oxygen-containing gas to the other electrode may be used. In this case, since a difference occurs in the pressure difference in each part of the electrolyte membrane, the generated water in such a part can be quickly reduced by adjusting the pressure difference in a part where a large amount of the generated water is generated or in a part where the generated water is easily stagnated. And the promotion of the deterioration of the electrolyte membrane at other portions can be prevented. In the polymer electrolyte fuel cell according to the aspect of the invention, in which the oxygen-containing gas is supplied such that the deviation of the pressure difference becomes large, the oxygen-containing gas supply unit includes the oxygen-containing gas and the oxygen-containing gas on the upstream side of the hydrogen-containing gas. The means for supplying the oxygen-containing gas to the electrode on the other side so that the pressure difference with the hydrogen-containing gas becomes large may be employed. In this case, the generated water generated on the upstream side of the hydrogen-containing gas can be quickly eliminated. Further, in the polymer electrolyte fuel cell according to the aspect of the present invention, wherein the oxygen-containing gas is supplied such that the deviation of the pressure difference is large, the oxygen-containing gas supply unit includes the oxygen-containing gas on the downstream side of the hydrogen-containing gas. And a means for supplying the oxygen-containing gas to the other electrode so that the pressure difference between the oxygen-containing gas and the hydrogen-containing gas increases. This makes it possible to quickly eliminate generated water generated on the downstream side of the hydrogen-containing gas.

[0013] Alternatively, in the polymer electrolyte fuel cell according to the present invention, the oxygen-containing gas supply means may reduce the deviation of the pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane. Supply of the oxygen-containing gas to the second electrode, and supply of the oxygen-containing gas to the other electrode, in which the deviation of the pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane increases. Supply switching means for switching between
The hydrogen-containing gas supply means includes: a supply of the hydrogen-containing gas to the one electrode where a deviation of a pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is reduced; and It is also possible to provide a supply switching means for switching the supply of the hydrogen-containing gas to the one-side electrode where the deviation of the pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each of the parts becomes large. In this case, water generated at the cathode can be eliminated according to the state of the polymer electrolyte fuel cell.

In the polymer electrolyte fuel cell according to the present invention, the hydrogen-containing gas supply means supplies the hydrogen-containing gas such that the hydrogen-containing gas flows in a predetermined direction as a whole over the surface of the one electrode. The oxygen-containing gas supply means supplies the oxygen-containing gas so that the oxygen-containing gas flows in a direction at a predetermined angle with respect to the predetermined direction as a whole over the surface of the other electrode. It can also be a means to perform. In the polymer electrolyte fuel cell according to the aspect of the present invention, the direction having the predetermined angle may be substantially the same direction as the predetermined direction, or may be a direction substantially opposite to the predetermined direction. ,
The direction may be substantially orthogonal to the predetermined direction. In the polymer electrolyte fuel cell according to the aspect of the present invention, the oxygen-containing gas supply unit has at least two different directions as the direction having the predetermined angle, and selects one of the directions. The means for supplying the oxygen-containing gas or the hydrogen-containing gas supply means has at least two different directions as the predetermined direction and selects one of the directions to supply the hydrogen-containing gas. It may be a means for supplying. In this case, water generated at the cathode can be eliminated according to the state of the polymer electrolyte fuel cell.

[0015]

Next, embodiments of the present invention will be described with reference to examples. FIG. 1 is a configuration diagram schematically showing a configuration of a polymer electrolyte fuel cell 10 as one embodiment of the present invention, and FIG. 2 is a part of a fuel cell stack 20 of the polymer electrolyte fuel cell 10 of the embodiment. FIG. As shown in FIG. 1, the polymer electrolyte fuel cell 10
The fuel cell stack 20 includes a plurality of fuel cell stacks 1 and 2. The fuel cell stack 20 is supplied with air as an oxygen-containing gas containing oxygen by a blower 52 and a hydrogen-containing gas containing hydrogen (not shown). It is supplied from a contained gas tank.

A supply pressure regulating valve 5 for regulating the pressure of the air supplied to the fuel cell stack 20 is provided in the air supply pipe 53.
4 is attached, and an exhaust pressure regulating valve 59 for adjusting exhaust pressure is attached to an exhaust gas pipe 58 of air from the fuel cell stack 20. Supply pipe 6 for hydrogen-containing gas
3 is also provided with a supply pressure regulating valve 64 for regulating the pressure of the hydrogen-containing gas supplied to the fuel cell stack 20, and an exhaust pressure regulating valve 69 for regulating the exhaust pressure is also provided in the exhaust gas pipe 68. Installed. It should be noted that the fuel cell stack 20 is supplied with water as a cooling medium to cool the heat generated by the power generation in each of the cells 21.

As shown in FIG. 2, the fuel cell stack 20 is formed by stacking a plurality of unit cells 21. The unit cells 21 are made of a polymer material such as a fluororesin, for example, DuP.
The electrolyte membrane 22 which is a proton conductive membrane formed by Nafion 112 manufactured by Ont Co., and carbon particles carrying platinum or an alloy made of platinum and another metal are screen-printed on both surfaces of the electrolyte membrane 22. The formed cathode 26 and anode 28 and electrolyte membrane 22
And an oxygen-containing gas flow path 34 as a flow path for an oxygen-containing oxygen-containing gas (in the embodiment, air is used) disposed on the side of the cathode 26 and a cooling medium (in the embodiment,
An oxygen-containing gas-side separator 30 forming a cooling medium flow path 38 as a flow path (using water), and a hydrogen-containing gas as a flow path for a hydrogen-containing hydrogen-containing gas disposed on the anode 28 side of the electrolyte membrane 22. It is constituted by a hydrogen-containing gas side separator 40 forming a flow path 44.

FIG. 3 is a cross-sectional view illustrating a cross section of the electrolyte membrane 22 in the plane direction. As shown, a reinforcing member 24 for reinforcing the strength of the electrolyte membrane 22 is provided inside the electrolyte membrane 22.
Is embedded. The reinforcing member 24 is formed of the electrolyte membrane 2
2 is made of a material that does not impair the function as an electrolyte, that is, a proton conductive function, for example, a material such as a resin such as polytetrafluoroethylene, and is unbalanced so as to be biased in one direction as shown in FIG. Have been. The arrangement of the reinforcing member 24 will be described later.

FIG. 4 is a plan view illustrating a side of the oxygen-containing gas separator 30 on which the oxygen-containing gas flow path 34 is formed. The oxygen-containing gas-side separator 30 is made of dense carbon which is made by compressing and densifying carbon to be gas-impermeable. As shown, an air supply port 31 as an oxygen-containing gas and an air discharge port are provided. And a rib 32 forming a groove for connecting the supply port 31 and the discharge port 35 with three rows of serpentine grooves. The three rows of the serpentine grooves are formed by the ribs 32 on the electrolyte membrane 22.
The oxygen-containing gas flow path 34 described above is formed by contacting the gas. The supply port 31 is connected to an air supply pipe 53 shown in FIG. 1 so that air whose supply pressure is adjusted is supplied. The exhaust port 35 is connected to an exhaust gas pipe 58 for air, so that exhaust gas whose exhaust pressure is adjusted is exhausted. Although not shown, the back surface of the oxygen-containing gas-side separator 30 has substantially the same configuration as the display surface, and a supply port and a discharge port of water as a cooling medium supplied to the fuel cell stack 20, a cooling medium flow path A rib 36 for forming the ridge 38 is formed.

The hydrogen-containing gas-side separator 40 is also made of the same material as the oxygen-containing gas-side separator 30, and has the same shape as the display surface of the oxygen-containing gas-side separator 30 shown in FIG. Nothing is formed on the back surface of the hydrogen-containing gas-side separator 40, and the back surface is flat. The supply port 41 formed in the hydrogen-containing gas side separator 40 is connected to a supply pipe 63 of the hydrogen-containing gas, and is supplied with the hydrogen-containing gas whose supply pressure is adjusted. Is connected to an exhaust gas pipe 68 of a hydrogen-containing gas so that exhaust gas whose exhaust pressure is adjusted is discharged.

FIG. 5 is an explanatory view schematically illustrating a state of supply when air or a hydrogen-containing gas is supplied to the oxygen-containing gas-side separator 30 or the hydrogen-containing gas-side separator 40. As shown in the drawing, in the fuel cell stack 20 of the embodiment, the supply port 31 and the supply port 41 of the oxygen-containing gas-side separator 30 and the hydrogen-containing gas-side separator 40 are aligned with the discharge port 35 and the discharge port 45, respectively. The oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 are arranged so as to detour in the same direction with the electrolyte membrane 22 therebetween and reach from the supply port 31 or the supply port 41 to the discharge port 35 or the discharge port 45. .

FIG. 6 shows a polymer electrolyte fuel cell 1 of the embodiment.
FIG. 4 is an explanatory diagram illustrating a state of a change in pressure of air or a hydrogen-containing gas in an oxygen-containing gas channel and a hydrogen-containing gas channel when 0 is in an operating state. In the fuel cell stack 20 of the embodiment, the pressure of the air flowing through the oxygen-containing gas flow path 34 is higher than the pressure of the hydrogen-containing gas flowing through the hydrogen-containing gas flow path 44 with the electrolyte membrane 22 interposed therebetween. The difference is the supply ports 31 and 4 for air or hydrogen-containing gas.
The supply pressure regulating valve 54, the exhaust pressure regulating valve 59, and the supply pressure regulating valve 64 are set so as to decrease from 1 toward the discharge ports 35 and 45.
And the exhaust pressure regulating valve 69 is adjusted. The reason for providing the pressure difference between the air and the hydrogen-containing gas is that the water generated by the reaction of the above formula (2) is passed through the electrolyte membrane 22 to the anode 28 side on the cathode 26 side surface of the electrolyte membrane 22. It is to eliminate. The reason why the pressure difference in the vicinity of the supply ports 31 and 41 is larger than the pressure difference in the vicinity of the discharge ports 35 and 45 is that the above formulas (1) and This is because the reaction of (2) is actively performed, and a large amount of water generated by the reaction is removed to the anode 28 side. The degree of the pressure difference is designed based on the degree of water generation, the degree of water permeability of the electrolyte membrane 22, the strength of the electrolyte membrane 22, and the like.

The reinforcing member 24 inside the electrolyte membrane 22 described above
Is provided to reinforce the electrolyte membrane 22 against the pressure difference between the air supplied to the oxygen-containing gas flow path 34 and the hydrogen-containing gas supplied to the hydrogen-containing gas flow path 44. . The arrangement of the reinforcing member 24 shown in FIG. 3 is such that the reinforcing member 2 has a large reinforcing force at a large pressure difference.
4 are densely arranged.

According to the polymer electrolyte fuel cell 10 of the embodiment described above, the supply pressure of air as the oxygen-containing gas supplied to the electrolyte membrane 22 is higher than the supply pressure of the hydrogen-containing gas supplied to the electrolyte membrane 22. By doing so, the cathode 26
Can be removed to the anode 28 side through the electrolyte membrane 22. The movement of water to the anode 28 side is caused by the proton membrane 2 generated by the anode 28.
It also supplements the water used for the movement of 2. Therefore, the oxygen in the air can be continuously supplied to the catalyst by eliminating the generated water at the cathode 26, and the generated protons can be promptly moved through the electrolyte membrane 22 to the cathode 26 side at the anode 28. The protonation of hydrogen can be performed continuously.

The polymer electrolyte fuel cell 10 of the embodiment
According to the method, since the reinforcing member 24 for reinforcing the electrolyte membrane 22 is provided, the strength of the electrolyte membrane 22 can be increased, and the promotion of breakage and deterioration of the electrolyte membrane 22 can be prevented. Moreover, since the reinforcing member 24 is disposed according to the pressure difference between the air and the hydrogen-containing gas, the entire electrolyte membrane 22 can be made uniform.

Further, the polymer electrolyte fuel cell 1 of the embodiment
According to 0, since the pressure difference between the air and the hydrogen-containing gas was adjusted so as to decrease from the supply ports 31 and 41 of the air and the hydrogen-containing gas toward the discharge ports 35 and 45, the supply ports 31 and 41 were adjusted.
A large amount of generated water generated in the vicinity where the hydrogen concentration is high can be efficiently removed to the anode 28 side.

In the polymer electrolyte fuel cell 10 of the embodiment,
As shown in FIG. 6, the pressure difference between the air and the hydrogen-containing gas near the supply ports 31 and 41 was adjusted to be larger than that near the discharge ports 35 and 45. May be adjusted so as to be substantially uniform from the supply ports 31 and 41 toward the discharge ports 35 and 45. In this case, since the entire electrolyte membrane 22 has a uniform pressure difference, water generated at the cathode 26 can be uniformly eliminated from the entire electrolyte membrane 22. Partial deterioration and breakage of the electrolyte membrane 22 can be prevented. In this case, the reinforcing members 24 embedded in the electrolyte membrane 22 are arranged so as to be uniform over the entire electrolyte membrane 22. In this modification, the supply pressure regulating valve 54 attached to the air supply pipe 53 and the exhaust pressure regulating valve 59 attached to the exhaust gas pipe 58 of the polymer electrolyte fuel cell 10 of the embodiment, or the supply of hydrogen-containing gas Since it can be constituted only by adjusting the supply pressure regulating valve 64 attached to the pipe 63 and the exhaust pressure regulating valve 69 attached to the exhaust gas pipe 68, these regulation can be performed according to the operation state of the polymer electrolyte fuel cell 10. By adjusting the pressure valves 54, 59, 64, 69, the pressure difference between the air and the hydrogen-containing gas near the supply ports 31, 41 becomes larger than that near the discharge ports 35, 45. Pressure difference with supply port 3
It is also possible to switch from a state where the discharge ports 35 and 45 are substantially uniform toward the discharge ports 35 and 45.

In the fuel cell stack 20 of the embodiment, the oxygen-containing gas-side separator 30 and the hydrogen-containing gas-side separator 40 are aligned with the supply port 31 and the supply port 41 and the discharge port 35 and the discharge port 45, respectively. Although the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 are arranged so as to detour in the same direction with the electrolyte membrane 22 interposed therebetween and reach from the supply port 31 or the supply port 41 to the discharge port 35 or the discharge port 45. , Oxygen-containing gas side separator 30 and hydrogen-containing gas side separator 4
0, the supply port 31 and the discharge port 45 are aligned, and the discharge port 35
And the supply port 41 are aligned, and the oxygen-containing gas flow path 34
And the hydrogen-containing gas flow path 44 may be arranged so as to detour in the opposite direction across the electrolyte membrane 22 and to reach the outlet 35 or the outlet 45 from the supply port 31 or the supply port 41. FIG. 7 is a schematic diagram of the oxygen-containing gas separator 30 and the hydrogen-containing gas separator 40 in this arrangement, and shows the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 in the operating state in this arrangement.
FIG. 8 shows an example of how the pressure of the air or the hydrogen-containing gas changes in the above. In this case, since the air and the hydrogen-containing gas flow in opposite directions, the pressure difference near the air supply port 31 is large and the pressure difference near the supply port 41 is small as shown in FIG. In this case, the generated water generated in the vicinity of the air outlet 35 can be efficiently eliminated.

As a method of arranging the oxygen-containing gas side separator 30 and the hydrogen-containing gas side separator 40, as shown in a modification illustrated in FIG. 9, the supply port 31, the supply port 41, and the discharge port 35, the discharge port 45 are provided. The oxygen-containing gas-side separator 30 and the hydrogen-containing gas-side separator 40 are arranged so that they do not match each other and the air and the hydrogen-containing gas flow from the left to the right in the figure as a whole. Thus, the supply port 41 and the discharge port 45 of the hydrogen-containing gas-side separator 40 illustrated in FIG. 9 may be replaced with each other. In the modification illustrated in FIG. 9, the flow direction is substantially the same as that in the embodiment illustrated in FIG. 5. Therefore, the flow direction is close to the pressure change illustrated in FIG. 6. In the modification illustrated in FIG. Since the flow direction is the same as that of the modified example illustrated in FIG. 7, it is close to the pressure change illustrated in FIG. Needless to say, the modification illustrated in FIG. 9 has the same effect as the embodiment, and the modification illustrated in FIG. 10 has the same effect as the modification illustrated in FIG.

In addition, the oxygen-containing gas separator 30 and the hydrogen-containing gas separator 40 may be arranged so that the oxygen-containing gas passage 34 and the hydrogen-containing gas passage 44 are orthogonal to each other. FIG. 11 shows the oxygen-containing gas side separator 3 so that the oxygen-containing gas passage 34 and the hydrogen-containing gas passage 44 are orthogonal to each other.
It is explanatory drawing which shows typically the arrangement method of arrange | positioning 0 and the hydrogen-containing gas side separator 40. FIG. 11A shows an arrangement of the oxygen-containing gas separator 30. FIGS. 11B to 11E show four arrangements of the hydrogen-containing gas separator 40 with respect to the oxygen-containing gas separator 30 of FIG.
There are two patterns. In FIG. 11, the hydrogen-containing gas separator 40 is based on the oxygen-containing gas separator 30.
However, it is needless to say that the pattern of the oxygen-containing gas-side separator 30 is changed with reference to the hydrogen-containing gas-side separator 40.
In any of the illustrated patterns, by adjusting the pressure of the air near the outlet 35 of the oxygen-containing gas separator 30 to be higher than the pressure of the hydrogen-containing gas near the supply port 41 of the hydrogen-containing gas separator 40, Since the pressure of the air can be made higher than the pressure of the hydrogen-containing gas also at the part, the water generated at the cathode 26 can be removed to the anode 28 side.

In the polymer electrolyte fuel cell 10 of the embodiment,
Although the oxygen-containing gas side separator 30 and the hydrogen-containing gas side separator 40 forming the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 formed so that the air and the hydrogen-containing gas flow in a bypass manner are used, As a device using an oxygen-containing gas side separator or a hydrogen-containing gas side separator forming an oxygen-containing gas flow path or a hydrogen-containing gas flow path formed so that the hydrogen-containing gas flows linearly from one side to the opposite side. Is also good. FIG. 12 shows an example of such an oxygen-containing gas-side separator. The oxygen-containing gas-side separator 30B of this modified example is formed in a state in which the whole is excavated one step except for the edge, and a plurality of convex portions 32B having a circular or rectangular cross section are formed in front of the excavated portion. I have. In the oxygen-containing gas side separator 30B, the protrusions 3
The portion dug down by the contact of 2B with the electrolyte membrane 22 becomes the air flow path 34B. Also, four air supply ports 31B are formed near the left edge of the oxygen-containing gas side separator 30B in the figure, and four discharge ports 35B are formed near the right edge in the figure. If the same shape as the oxygen-containing gas separator 30B illustrated in FIG. 12 is used as the hydrogen-containing gas separator 40B, the oxygen-containing gas separator 30B and the hydrogen-containing gas separator 40B are used.
The pattern of the arrangement with B is as shown in FIG. FIG.
In FIG. 3, the oxygen-containing gas-side separator 30 shown in FIG.
The patterns of the hydrogen-containing gas side separator 40 based on B are shown in FIGS. In any of these patterns, by adjusting the pressure of air near the outlet 35B of the oxygen-containing gas separator 30B to be higher than the pressure of the hydrogen-containing gas near the supply port 41B of the hydrogen-containing gas separator 40B, Since the pressure of the air can be made higher than the pressure of the hydrogen-containing gas also at the portion, the water generated at the cathode 26 can be removed to the anode 28 side. If the pattern of FIG. 13B is selected from these putters, the air and the hydrogen-containing gas flow in parallel in the same direction. FIG. 6 shows a pressure change similar to the embodiment illustrated in FIG.
On the other hand, if the pattern of FIG. 13 (c) is selected, since the air and the hydrogen-containing gas flow in parallel and in opposite directions, the change in pressure in the flow path is similar to that of FIG. 8 shows a pressure change similar to that of the modification illustrated in FIG.

In addition, the way of flowing the air and the hydrogen-containing gas is as follows: the oxygen-containing gas-side separator 30B illustrated in FIG. 4 and the hydrogen-containing gas-side separator 40B illustrated in FIG. Figure 14 using
FIG. 15 shows a pattern schematically shown in FIG. 15 and, conversely, a hydrogen-containing gas-side separator 40 identical to the oxygen-containing gas-side separator 30 illustrated in FIG. 4 and an oxygen-containing gas-side separator 30B illustrated in FIG. It can also be a pattern shown schematically. In any of the patterns illustrated in FIGS. 14 and 15, the oxygen-containing gas-side separator 30,
The pressure of the air in the vicinity of the outlets 35, 35B of the 30B is the supply port 41 of the hydrogen-containing gas side separators 40B, 40
By adjusting the pressure of the hydrogen-containing gas to be higher than the pressures of the hydrogen-containing gas in the vicinity of B and 41, the pressure of the air can be made higher than the pressure of the hydrogen-containing gas at any position. It can be eliminated on the anode 28 side.

In the polymer electrolyte fuel cell 10 of the embodiment,
The electrolyte membrane 22 is formed using a rod-shaped reinforcing member 24 having a uniform thickness.
However, as shown in a modified example of the electrolyte membrane 22C illustrated in FIG. 16, the reinforcing member 24C may be formed by using a rod having a variable diameter. In this case, it goes without saying that the reinforcing member 24C is arranged so that the diameter of the portion where the pressure difference between the air and the hydrogen-containing gas is large is large. Further, as shown in a modified example of the electrolyte membrane 22D in FIG. 17, the reinforcing member 24D may be arranged so as to interpolate.

In the polymer electrolyte fuel cell 10 of the embodiment,
Although the reinforcing member 24 is embedded in the electrolyte membrane 22,
A reinforcing member 24E or a reinforcing member 24F like the electrolyte membrane 22E of the modification of FIG. 18 or the electrolyte membrane 22F of the modification of FIG.
May not be embedded in the electrolyte membranes 22E and 22F, but may be arranged on the surface thereof. In the case where the reinforcing member 24E is disposed on the anode 28 side as illustrated in FIG. 18, the reinforcing member 24E is formed of a material having an advantageous tensile strength, and the reinforcing member 24F is disposed on the cathode 26 side as illustrated in FIG. In this case, the reinforcing member 24F may be formed of a material that is advantageous in compressive strength.

In the polymer electrolyte fuel cell 10 of the embodiment,
Although the bar is used as the reinforcing member 24, a short fiber may be used like the reinforcing member 24G embedded in the electrolyte membrane 22G of the modification of FIG. In this case, the amount of short fibers to be embedded may be adjusted according to the pressure difference between the air and the hydrogen-containing gas.

In the polymer electrolyte fuel cell 10 of the embodiment,
Although it is configured to supply the air and the hydrogen-containing gas to the fuel cell stack 20 from one direction, as shown in a schematic diagram illustrating a fuel cell stack 20H of a modified example in FIG.
Oxygen and a hydrogen-containing gas may be supplied to each cell alternately from above in the figure and from below in the figure. In FIG. 21, the electrolyte membrane 22 and the oxygen-containing gas-side separator 3
0, hydrogen-containing gas side separator 40 is schematically shown. The difference between the thickness of the electrolyte membrane 22 and the thickness of the electrolyte membrane 22 is due to the arrangement of the reinforcing member 24. In FIG.
Are stacked in such a manner that the thicker part is located at the top in the figure and the part located at the bottom in the figure is alternately arranged. By doing so, the fuel cell stack 20H of the modified example can be kept in a rectangular shape.

In the polymer electrolyte fuel cell 10 of the embodiment,
As illustrated in FIG. 5, as shown in FIG.
And the hydrogen-containing gas side separator 40 with the supply port 31
And the supply port 41 and the discharge port 35 and the discharge port 45 are aligned with each other, and the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44
Are bypassed in the same direction with the electrolyte membrane 22 interposed therebetween.
Or from the supply port 41 to the discharge port 35 or the discharge port 45 so that the pressure difference between the air and the hydrogen-containing gas near the supply ports 31 and 41 is larger than that near the discharge ports 35 and 45. Alternatively, as shown in the modified example, the pressure difference between the air and the hydrogen-containing gas is made substantially uniform from the supply ports 31 and 41 toward the discharge ports 35 and 45. The arrangement of the hydrogen-containing gas-side separator 40 and the arrangement of the oxygen-containing gas-side separator 30 and the hydrogen-containing gas-side separator 40 illustrated in FIG. 7, that is, the supply port 31 and the discharge port 45 match, and the discharge port 35 And the supply port 41 are aligned with each other, and the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 detour in opposite directions with the electrolyte membrane 22 interposed therebetween.
5 and the arrangement leading to the discharge port 45 may be switched and used. In this case, as exemplified in the polymer electrolyte fuel cell 10J of the modified example of FIG. 22, the configuration may be such that the pipe for supplying air from the supply port 31 and the pipe for supplying air from the discharge port 35 can be switched. . In the polymer electrolyte fuel cell 10J of the modification, the supply pipe 53 is connected to the three-way valve 5.
5, connected to the hydrogen-containing gas supply pipe 63 side of the fuel cell stack 20J via the first supply pipe 56a and the three-way valve 57a, and the three-way valve 55, the second supply pipe 56b, and the three-way valve 5
The fuel cell stack 20J is connected to the hydrogen-containing gas exhaust gas pipe 68 via the fuel cell stack 7b. Also, the three-way valve 57
Exhaust gas pipes 58a, 58b are attached to the exhaust gas pipes 58a, 58b.
a, 59b are attached.

Therefore, the supply pipe 53 and the first supply pipe 56
The three-way valve 55 is operated so that the
b and the first supply pipe 56a so as not to communicate with each other.
By operating the three-way valve 57b so that the second supply pipe 56b and the exhaust gas pipe 58a do not communicate with each other,
Since the fuel is supplied from the supply pipe 53 to the fuel cell stack 20J through the first supply pipe 56a and discharged from the exhaust gas pipe 58a, the pattern illustrated in FIG. 5 is obtained. On the other hand, supply pipe 5
The three-way valve 55 is operated so that the third and third supply pipes 56b communicate with each other, and the three-way valve 57b is operated so that the exhaust gas pipe 58a and the second supply pipe 56b do not communicate with each other.
If the three-way valve 57a is operated so that the exhaust gas pipe 58b and the exhaust gas pipe 58b do not communicate with each other, air is supplied from the supply pipe 53 to the fuel cell stack 20J through the second supply pipe 56b.
8b, the pattern illustrated in FIG. 7 is obtained. As described above, in the polymer electrolyte fuel cell 10J of this modification, the pattern illustrated in FIG. 5 and the pattern illustrated in FIG. 7 can be switched. As a result, the operation can be performed in a more appropriate pattern according to the operation state of the polymer electrolyte fuel cell 10J. In addition,
In the polymer electrolyte fuel cell 10J of the modified example, the oxygen-containing gas-side separator 30 and the hydrogen-containing gas-side separator 40 illustrated in FIG. 4 are used, but the oxygen-containing gas-side separator 30B illustrated in FIG. Side separator 40
B may be used, or the oxygen-containing gas separator 30 and the hydrogen-containing gas separator 40B may be used, or the oxygen-containing gas separator 30B and the hydrogen-containing gas separator 40 may be used.

The embodiments of the present invention have been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various embodiments may be made without departing from the scope of the present invention. Of course, it can be carried out.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing the configuration of a polymer electrolyte fuel cell 10 as one embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a part of a fuel cell stack 20 of the polymer electrolyte fuel cell 10 according to the embodiment.

FIG. 3 is a cross-sectional view illustrating a cross section in a plane direction of an electrolyte membrane 22;

FIG. 4 is a plan view illustrating a surface of the oxygen-containing gas separator 30 on which the oxygen-containing gas channel 34 is formed.

FIG. 5 is an explanatory diagram schematically illustrating a state of supply when air or a hydrogen-containing gas is supplied to the oxygen-containing gas-side separator 30 or the hydrogen-containing gas-side separator 40.

FIG. 6 is a view exemplifying a state of a change in the pressure of air or a hydrogen-containing gas in the oxygen-containing gas flow path 34 or the hydrogen-containing gas flow path 44 when the polymer electrolyte fuel cell 10 of the embodiment is in an operating state. FIG.

FIG. 7 is an oxygen-containing gas side separator 3 in a modified example.
FIG. 4 is an explanatory view schematically showing a state of supply when air or a hydrogen-containing gas is supplied to the separator 40 on the side of 0 or the hydrogen-containing gas.

FIG. 8 is an explanatory view exemplifying a state of a change in pressure of air or a hydrogen-containing gas in an oxygen-containing gas flow path and a hydrogen-containing gas flow path in an operating state in a modified example.

FIG. 9 shows an oxygen-containing gas-side separator 3 according to a modification.
FIG. 4 is an explanatory view schematically showing a state of supply when air or a hydrogen-containing gas is supplied to the separator 40 on the side of 0 or the hydrogen-containing gas.

FIG. 10 is an explanatory diagram schematically showing a state of supply when supplying air or a hydrogen-containing gas to an oxygen-containing gas-side separator 30 or a hydrogen-containing gas-side separator 40 in a modified example.

FIG. 11 is an explanatory view schematically showing an arrangement method of arranging the oxygen-containing gas separator 30 and the hydrogen-containing gas separator 40 such that the oxygen-containing gas flow path 34 and the hydrogen-containing gas flow path 44 are orthogonal to each other. .

FIG. 12 is a modified example of the oxygen-containing gas side separator 30B.
It is explanatory drawing which illustrates.

FIG. 13 is a modified example of the oxygen-containing gas side separator 30B.
It is explanatory drawing which illustrates typically the pattern of arrangement | positioning at the time of using the hydrogen containing gas side separator 40B.

FIG. 14 is an explanatory diagram schematically illustrating an arrangement pattern when the oxygen-containing gas-side separator 30 of the embodiment and the hydrogen-containing gas-side separator 40B of the modification are used.

FIG. 15 is a modified example of the oxygen-containing gas side separator 30B.
It is explanatory drawing which illustrates typically the pattern of arrangement | positioning at the time of using the hydrogen containing gas side separator 40 of an Example.

FIG. 16 is an explanatory view exemplifying an arrangement of a reinforcing member 24C of a modified example.

FIG. 17 is an explanatory view illustrating the arrangement of a reinforcing member 24D according to a modified example.

FIG. 18 is an explanatory view illustrating the arrangement of a reinforcing member 24E according to a modified example.

FIG. 19 is an explanatory view illustrating the arrangement of a reinforcing member 24F according to a modified example.

FIG. 20 is an explanatory view illustrating an electrolyte membrane 22G using a reinforcing member 24G of a modified example.

FIG. 21 is an explanatory view schematically showing a fuel cell stack 20H of a modified example.

FIG. 22 is a configuration diagram schematically illustrating a configuration of a polymer electrolyte fuel cell 10J according to a modification.

[Explanation of symbols]

10, 10J polymer electrolyte fuel cell, 20, 20H,
20J fuel cell stack, 21 cells, 22, 22
C, 22D, 22E, 22F, 22G electrolyte membrane, 2
4, 24C, 24D, 24E, 24F, 24G Reinforcing member, 26 cathode, 28 anode, 30, 30B
Oxygen-containing gas side separator, 31, 31B supply port, 32
Rib, 32B convex portion, 34, 34B oxygen-containing gas flow path, 35, 35B outlet, 36 rib, 38 cooling medium flow path, 40, 40B hydrogen-containing gas side separator, 4
1, 41B supply port, 42 rib, 44 hydrogen-containing gas flow path, 45, 45B discharge port, 52 blower, 53 supply pipe, 54 supply pressure regulating valve, 55 three-way valve, 56a first supply pipe, 56b second supply pipe , 57a, 57b three-way valve, 58, 58a, 58b exhaust gas pipe, 59, 59a,
59b exhaust pressure regulating valve, 63 supply pipe, 64 supply pressure regulating valve, 68 exhaust gas pipe, 69 exhaust pressure regulating valve.

Claims (15)

[Claims] 1. A polymer electrolyte fuel cell comprising an electrolyte membrane formed of a solid polymer sandwiched between two electrodes, wherein a hydrogen-containing gas containing hydrogen is supplied to one electrode of the electrolyte membrane. A solid polymer fuel comprising: a hydrogen-containing gas supply means; and an oxygen-containing gas supply means for supplying an oxygen-containing gas containing oxygen at a pressure higher than the supply pressure of the hydrogen-containing gas to the other electrode of the electrolyte membrane. battery. 2. The polymer electrolyte fuel cell according to claim 1, further comprising reinforcing means disposed inside and / or on the surface of the electrolyte membrane to reinforce the strength of the electrolyte membrane. 3. The solid height as set forth in claim 2, wherein said reinforcing means changes the degree of reinforcement of each part of said electrolyte membrane in accordance with a pressure difference between said hydrogen-containing gas and said oxygen-containing gas. Molecular fuel cell. 4. The oxygen-containing gas supply means supplies the oxygen-containing gas to the electrode on the other side such that a deviation of a pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is reduced. The polymer electrolyte fuel cell according to any one of claims 1 to 3, which is a means for performing. 5. The oxygen-containing gas supply means supplies the oxygen-containing gas to the electrode on the other side such that a deviation of a pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane becomes large. The polymer electrolyte fuel cell according to any one of claims 1 to 3, which is a means for performing. 6. The oxygen-containing gas supply means supplies the oxygen-containing gas to the electrode on the other side such that a pressure difference between the oxygen-containing gas and the hydrogen-containing gas on the upstream side of the hydrogen-containing gas is increased. The polymer electrolyte fuel cell according to claim 5, which is a means for performing. 7. The oxygen-containing gas supply means supplies the oxygen-containing gas to the electrode on the other side such that a pressure difference between the oxygen-containing gas and the hydrogen-containing gas downstream of the hydrogen-containing gas is increased. The polymer electrolyte fuel cell according to claim 5, which is a means for performing. 8. The oxygen-containing gas supply means supplies the oxygen-containing gas to the electrode on the other side where a difference in pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is reduced. And supply switching means for switching between supply of the oxygen-containing gas to the other electrode where the deviation of the pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is large. 4. The polymer electrolyte fuel cell according to any one of claims 3 to 3. 9. The hydrogen-containing gas supply means supplies the hydrogen-containing gas to the one electrode in which a difference in pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is reduced. And supply switching means for switching the supply of the hydrogen-containing gas to the one electrode where the deviation of the pressure difference between the oxygen-containing gas and the hydrogen-containing gas in each part of the electrolyte membrane is large. 4. The polymer electrolyte fuel cell according to any one of claims 3 to 3. 10. The polymer electrolyte fuel cell according to claim 1, wherein said hydrogen-containing gas supply means is configured to supply said hydrogen-containing gas in a predetermined direction over the entire surface of said one electrode. Means for supplying the hydrogen-containing gas so as to flow, wherein the oxygen-containing gas supply means is arranged such that the oxygen-containing gas has a predetermined angle with respect to the predetermined direction with respect to the entire surface of the electrode on the other side. A polymer electrolyte fuel cell which is a means for supplying the oxygen-containing gas in a flowing manner. 11. The polymer electrolyte fuel cell according to claim 10, wherein the direction having the predetermined angle is substantially the same as the predetermined direction. 12. The polymer electrolyte fuel cell according to claim 10, wherein the direction having the predetermined angle is substantially opposite to the predetermined direction. 13. The polymer electrolyte fuel cell according to claim 10, wherein the direction having the predetermined angle is a direction substantially orthogonal to the predetermined direction. 14. The oxygen-containing gas supply means has at least two different directions as the directions having the predetermined angle, and selects one of the directions to supply the oxygen-containing gas. The polymer electrolyte fuel cell according to claim 10, which is a means. 15. The hydrogen-containing gas supply means has at least two different directions as the predetermined direction, and selects one of the directions to supply the hydrogen-containing gas. 11. The polymer electrolyte fuel cell according to item 10.