JP2003031246A - Solid polymer fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce pressure loss of reaction gas in a fuel cell system humidifying un-reacted gas via a water retaining porous body by using reacted gas of a fuel cell. SOLUTION: The pressure loss of the reactive gas can be reduced by providing a solid polymer fuel cell stack 1 with a plurality of laminated single cells using solid polymer films 6 as electrolytes and a humidity and temperature exchanging means with a plurality of humidity and temperature exchanging cells exchanging heat and moisture of the reacted gas having passed a reaction part of the fuel cell stack 1 and the un-reacted gas before passing the reaction part of the fuel cell stack 1 laminated perpendicularly to a laminating direction of the single cells, and integrating reactive gas collecting and distributing manifolds for the humidity and temperature exchanging means and reactive gas collecting and distributing manifolds for the fuel cell stack.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid polymer fuel cell system using a solid polymer having ion conductivity as an electrolyte.

[0002]

2. Description of the Related Art In recent years, fuel cells have been attracting attention as a highly efficient energy conversion device. A fuel cell using a solid polymer electrolyte membrane having proton conductivity as an electrolyte has a compact structure, high output density, and can be operated with a simple system. It is attracting attention as a power source.

In a general fuel cell system, a hydrocarbon such as methane or an alcohol such as methanol is used as a fuel, and a reformer for reforming the fuel to produce a hydrogen-rich gas and a shift for reducing CO in the hydrogen-rich gas are used. It consists of a reactor and a selective oxidizer, a compressor that supplies air as an oxidant, a cooling system that removes heat generated by the cell reaction, and a fuel cell body.

In the fuel cell main body, hydrogen ions are produced from hydrogen contained in the fuel gas, conduct through the electrolyte membrane and react with oxygen contained in the oxidant gas to produce water. At that time, a part of the chemical energy of hydrogen is directly extracted as electric energy.

The electrolyte membrane shows good hydrogen ion conductivity in a water-containing state. For this reason, it is indispensable to moisturize the electrolyte membrane to keep it in a water-containing state during operation. As the humidifying method, an external humidifying method of adding water vapor to the reaction gas in advance,
Indirect internal humidification method in which battery cooling water and unreacted gas are contacted through a humidifying membrane and a portion of battery cooling water is added to unreacted gas, direct internal supply of battery cooling water to reaction gas in battery reaction section A humidification method is known.

On the other hand, the already-reacted gas that has passed through the battery portion and the unreacted gas that has not yet passed through the battery portion are brought into contact with each other through the water-retaining porous body, and the water contained in the already-reacted gas is added to the unreacted gas. A humidification method has been proposed. In this method, since the water contained in the already-reacted gas is used as the water for humidification, it is not necessary to prepare the water for humidification in advance, and since the cooling water is not used for the humidification, it is necessary to use pure water. Absent. Therefore, by using the antifreeze liquid as the cooling water, the water tank can be omitted, and a system that does not freeze even below the freezing point can be configured. This is ideal for automotive systems that require startup even below freezing.

FIG. 21 is a longitudinal sectional view showing a conventional fuel cell system of the type in which the unreacted oxidant gas is humidified by using the water of the already reacted oxidant gas. The fuel cell system comprises a fuel cell stack 1 and a temperature / humidity exchange means 20, which are integrally formed so that the respective constituent elements constituting them are laminated in the same direction, and are formed on the plate surfaces of the respective constituent elements. All the gas flow paths are vertical and are arranged such that the stacking directions are horizontal.

The fuel cell stack 1 includes a stack of a plurality of single cell batteries 2 stacked in the same direction (a plurality of single cell batteries 2).
Are arranged in parallel and are integrally connected to each other), and end plates 30 disposed at both axial ends of the laminated body are integrally formed.

The temperature / humidity exchange means 20 has a plurality of temperature / humidity exchange cells 21 stacked in the same direction (a plurality of temperature / humidity exchange cells 21 are arranged side by side and are integrally connected).
And an end plate 37 disposed at one end in the axial direction (a portion of the fuel cell stack 1 opposite to the portion in contact with the end plate 30).

Each temperature / humidity exchange cell 21 includes a water-retaining porous body 51 forming a temperature / humidity exchange membrane, and seal packings (not shown) respectively disposed on the surfaces of the porous body 51 facing each other.
The seal packing is composed of an unreacted oxidant gas separator 22 and an already reacted oxidant gas separator 23, which come into contact with the outer side surfaces of the seal packing. The unreacted oxidant gas supply manifold 27, the unreacted oxidant gas discharge manifold 28, the already-reacted oxidant gas supply manifold 36, and the already-reacted oxidant gas discharge manifold 31 are formed,
Gas passages (not shown) are formed on the plate surfaces of the separators 22 and 23. Further, an unreacted oxidant gas inlet 41 and an already-reacted oxidant gas outlet 42 are formed in the end plate 37, and the unreacted oxidant gas supply manifold 27 and the already-reacted oxidant are provided so as to penetrate in the thickness direction thereof. Gas exhaust manifolds 31 are formed respectively.

Each single cell battery 2 comprises a polymer electrolyte membrane (not shown), a fuel electrode (not shown) and an oxidizer electrode (not shown) disposed on both sides of the electrolyte membrane. The membrane electrode assembly 3, seal packings (not shown) provided on the back side of the fuel electrode and the oxidant electrode of the membrane electrode assembly 3, and the back side of these two seal packings, respectively. It is composed of a separator 5. A battery oxidant gas supply manifold 12, a battery oxidant gas discharge manifold 13, and a cooling water manifold (not shown) are formed in each separator 5 so as to penetrate in the thickness direction thereof,
In addition, a gas flow path (not shown) is formed on the plate surface.

A fuel inlet 43 and a fuel outlet 44 are formed on one side (right side in the drawing) of the end plate 30, and
For example, the fuel supply manifold (fuel gas supply manifold) 62, the fuel discharge manifold (fuel gas discharge manifold) 64, and the cooling water manifold 63 are configured in the same manner as the separator 5 of FIG. Each is formed. End plate 3
A battery oxidant gas supply manifold 12 and a battery oxidant gas discharge manifold 13 are formed on the other side (the left side in the drawing) of 0 so as to penetrate in the thickness direction.

In the conventional fuel cell system thus constructed, the oxidant gas inlet 4 of the end plate 37 is
The unreacted oxidant gas 53 (solid arrow with solid line in FIG. 21) supplied to the unreacted oxidant gas supply manifold 27 of the temperature / humidity exchange means 20 obtained via 1 It is guided to the unreacted oxidant gas exhaust manifold 28 through the gas flow path formed in the agent gas separator 22,
Unreacted oxidant gas 53 led to the exhaust manifold 28
Is introduced into the cell oxidant gas discharge manifold 13 through the cell oxidant gas supply manifold 12 formed in the fuel cell stack 1 and the gas flow path formed in the separator 5. As a result, the reacted oxidant gas 52 (broken line arrow having the same thickness as the solid line in FIG. 21) is guided to the battery oxidant gas discharge manifold 13. The reacted oxidant gas 52 is discharged from the oxidant gas outlet 42 of the end plate 37 through the reacted oxidant gas discharge manifold 31 of the temperature / humidity exchange means 20 and the unreacted oxidant gas discharge manifold 28. .

From the above description, the temperature / humidity exchange cell 21
Is composed of the unreacted oxidant gas separator 22, the water-retaining porous body 51, and the reacted oxidant gas separator 23, and the moisture contained in the reacted oxidant gas 52 distributed by the reacted oxidant gas supply manifold 36. Is condensed in the water-retaining porous body 51 and is evaporated in the unreacted oxidant gas 53 to add water to the unreacted oxidant gas 53.

In the fuel cell stack 1, the flow of fuel gas is as shown by the thin arrows in FIG. 21, and the flow of coolant is as shown by the solid arrows.

[0016]

In the conventional fuel cell system described above, the temperature / humidity exchange cell 21 and the single cell battery 2 are stacked in the same horizontal direction. Therefore, the unreacted oxidant gas 5 that has passed through the temperature / humidity exchange cell 21
3 were collected through an unreacted oxidant gas supply manifold 27 and an unreacted oxidant gas discharge manifold 28 which were provided at right angles to the temperature / humidity exchange cell 21, and were similarly provided in the fuel cell stack 1. It will be distributed to each single cell battery 2 through the battery oxidant gas supply manifold 12.

In this case, since the unreacted oxidant gas 53 needs to be evenly distributed to each temperature / humidity exchange cell 21 and each single cell battery 2, the manifold 27 for distributing the unreacted oxidant gas 53 is required. , 28, 36, 31 must be sufficiently large in cross section. Therefore, in the temperature / humidity exchange cell 21 and the single cell battery 2, the internal manifold,
That is, there is a problem in that the volume occupied by the battery oxidant gas supply manifold 12 and the battery oxidant gas discharge manifold 13 becomes large and the compactness is lost.

Further, as shown in the flow of oxidant gas in FIG. 22, the manifolds 27, 2 in the temperature / humidity exchange means 20 are shown.
8, 36, 31 and the manifolds 12, 13 in the fuel cell stack 1 are provided and connected in the same direction, so that the unreacted oxidant gas 53 passing through the temperature / humidity exchange means 20 is unreacted oxidant gas discharge manifold. A merged pressure loss occurs when the merged at 28, and similarly, a branched pressure loss occurs when the reacted oxidant gas 52 passing through the single cell battery 2 is distributed at the reacted oxidant gas supply manifold 36. There is also a problem that the pressure loss of the oxidant gas in the entire system becomes large due to the pressure loss of the branching / merging.

The present invention has been made to solve the above problems, and in a fuel cell system in which an unreacted gas is humidified through a water-retaining porous body using an already reacted gas,
An object of the present invention is to provide a polymer electrolyte fuel cell system capable of reducing the pressure loss of the reaction gas.

[0020]

In order to achieve the above-mentioned object, the invention according to claim 1 is a solid high battery comprising a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte, which are arranged in parallel and integrated. A molecular-type fuel cell stack, an already-reacted gas that has passed through the reaction section of the fuel cell stack, and an unreacted gas that has not passed through the reaction section of the fuel cell stack have the same shape of temperature for exchanging heat and moisture. In a polymer electrolyte fuel cell system including a temperature / humidity exchange means in which a plurality of humidity exchange cells are laminated and integrated, a stacking direction of the temperature / humidity exchange cells is substantially parallel to a parallel juxtaposition direction of the single cell batteries. The polymer electrolyte fuel cell system is characterized in that the fuel cell stack and the temperature / humidity exchange means are arranged in contact with each other so as to be at a right angle.

To achieve the above object, the invention according to claim 2 is characterized in that one end face in the parallel juxtaposition direction of the polymer electrolyte fuel cell stack and one end face in the stacking direction of the temperature / humidity exchange means are arranged. The polymer electrolyte fuel cell system according to claim 1, wherein the polymer electrolyte fuel cell system is arranged so as to abut.

In order to achieve the above object, the invention according to claim 3 is characterized in that one of the side surfaces of the solid polymer type fuel cell stack which is perpendicular to the parallel juxtaposition direction and one of the stacking direction of the temperature and humidity exchanging means. The solid polymer fuel cell system according to claim 1, wherein the solid polymer fuel cell system is arranged so that the end faces abut.

In order to achieve the above object, the invention according to claim 4 provides a solid polymer type fuel cell stack in which a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte are juxtaposed in parallel and integrated. , A plurality of temperature-humidity exchange cells having the same shape for exchanging heat and moisture between the already-reacted gas that has passed through the reaction section of the fuel cell stack and the unreacted gas before having passed through the reaction section of the fuel cell stack. In a polymer electrolyte fuel cell system including a temperature-humidity exchange means that is juxtaposed and integrated, in a parallel juxtaposition direction of the temperature-humidity exchange cells,
The polymer electrolyte fuel cell system is characterized in that the single cell batteries are arranged in contact with each other such that the parallel juxtaposition directions thereof are parallel to each other.

In order to achieve the above object, the invention according to claim 5 provides the solid polymer type fuel cell stack and the temperature / humidity exchanging means via a plate provided with a through hole for a reaction gas or a cooling medium. The polymer electrolyte fuel cell system according to claim 2, wherein the polymer electrolyte fuel cell system is integrated.

In order to achieve the above object, the invention according to claim 6 provides a solid polymer type fuel cell stack in which a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte are juxtaposed in parallel and integrated. A plurality of them are arranged side by side and integrally formed, and heat and moisture are exchanged between the already reacted gas that has passed through the reaction section of the fuel cell stack and the unreacted gas that has not yet passed through the reaction section of the fuel cell stack. In a polymer electrolyte fuel cell system having a temperature-humidity exchange means in which a plurality of temperature-humidity exchange cells of the same shape are arranged in parallel and integrated, the parallel juxtaposition direction of the temperature-humidity exchange cells is the same as that of the single-cell battery. The polymer electrolyte fuel cell system is characterized in that it is substantially perpendicular to the parallel juxtaposition direction and is substantially parallel to the arrangement direction of the plurality of polymer electrolyte fuel cell stacks. .

In order to achieve the above object, the invention according to claim 7 is the one end face in the parallel juxtaposition direction of the polymer electrolyte fuel cell stack and the one side face in the parallel juxtaposition direction of the temperature / humidity exchange means. The polymer electrolyte fuel cell system according to claim 6, wherein the fuel cell system and the fuel cell system are arranged so as to contact with each other.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 to 8 are views for explaining a first embodiment of a polymer electrolyte fuel cell system (referred to as a fuel cell system) according to the present invention. 1 is a perspective view showing an outline of a fuel cell system according to the present invention, and FIGS. 2 and 3 are cross-sectional views taken along line A--A and line B--B of FIG. 1, respectively. 5 and 6 are cross-sectional views taken along the lines C--C and D--D of FIG. 2, respectively, and FIGS. 6 and 7 explain the detailed structure of the temperature / humidity exchange means of FIGS. 2 and 3, respectively. FIG. 8 is a cross-sectional view for doing so, and FIG. 8 is a front view of the separator of the single cell battery 2.

The first embodiment of the present invention is the same as the above-mentioned conventional technique in that it is roughly composed of a solid polymer type fuel cell stack 1 and a temperature / humidity exchange means 20, but is different. The point is the configuration of the approximate temperature and humidity exchange means 20.

These configurations will be described below. In the fuel cell stack 1, a plurality of single cell batteries 2 having the same shape (here, only three are shown) are arranged in a horizontal direction [a plate of a membrane electrode assembly 3 and a separator 5 constituting a single cell battery 2 described later]. The gas flow paths formed on the respective surfaces are vertical, the parallel juxtaposition directions (stacking directions) of the constituent elements are parallel juxtaposed to each other, and the end plates 30 are arranged at both ends in the juxtaposed direction. And these are integrated. Each single cell battery 2 is roughly composed of the membrane electrode assembly 3 and the membrane electrode assembly 3
The seal packing 4 is disposed on both sides of the membrane electrode assembly 3 so as to sandwich it, and seals the fuel and the cell oxidant gas except a predetermined position (details will be described later), and both seal packings 4. And a separator 5 disposed so as to sandwich each of them are integrated.

As shown in FIG. 8, the separator 5 has a plurality of oxidant gas flow passages 60 formed in the horizontal direction on opposite plate surfaces of a plate having a rectangular outer shape, and a peripheral portion of the plate. The battery oxidant gas discharge manifold 13 is formed at the left end of the drawing in the thickness direction of the plate, and the right end of the drawing penetrates in the thickness direction of the plate. As described above, the battery oxidant gas supply manifold 12 is formed, and a plurality of cooling water manifolds 61 and fuel supply manifolds 62 are formed at the upper end of the drawing so as to penetrate in the thickness direction of the plate body. A plurality of cooling water manifolds 63 and a fuel discharge manifold 64 are formed at the lower end so as to penetrate in the thickness direction of the plate body.

Of the end plates 30, which are arranged at the right end portions of FIGS. 1, 2 and 3, the fuel inlet 43, the fuel outlet 44, the coolant outlet 45 and the coolant inlet (not shown) are provided. ) Has been formed. A battery oxidant gas supply manifold 12 and a battery oxidant gas discharge manifold 13 are formed on the remaining end plate 30.

Each of the membrane electrode assemblies 3 comprises a polymer electrolyte membrane 6, a fuel electrode 7 and an oxidant electrode 8, which constitute a reaction part for reacting a reaction gas.
The polymer electrolyte membrane 6 has a rectangular shape, and the fuel electrode 7 and the oxidizer electrode 8 are arranged on the plate surfaces of the electrolyte membrane 6 which face each other.

The temperature / humidity exchanging means 20 heats the fuel cell stack 1, the reacted gas that has passed through the reaction portion of the fuel cell stack 1, and the unreacted gas that has not passed through the reaction portion of the fuel cell stack 1. It is for exchanging water.

The temperature / humidity exchange means 20 comprises a plurality of temperature / humidity exchange cells 21 having the same shape and an unreacted oxidant gas separator 2.
2, a reacted oxidant gas separator 23, two horizontal end plates 32, and an end plate 37.

The unreacted oxidant gas separator 22 is a plate-shaped member, and mesh-shaped gas flow paths 22a are formed on the opposing plate surfaces, respectively, and one end (an end plate 37 described later abuts). Unreacted oxidant gas supply manifold 27 so as to penetrate therethrough in the thickness direction.
Are formed.

The already-reacted oxidant gas separator 23 is a plate-like member, and mesh-like gas flow paths 23a are formed on opposing plate surfaces, respectively, and one end (an end plate 37 described later comes into contact with the gas flow path 23a). An unreacted oxidant gas supply manifold 27 is formed near the portion) so as to penetrate in the thickness direction.

The temperature / humidity exchange cell 21 is disposed between the unreacted oxidant gas separator 22 and the already-reacted oxidant gas supply manifold separator 23, and has a temperature / humidity exchange membrane 24 made of a water-retentive porous body and the opposite. The seal packing 25 and one end portion of the temperature / humidity exchange membrane 24 (an end plate 37, which will be described later).
The unreacted oxidant gas supply manifold 27 and the already-reacted oxidant gas discharge manifold 31 are formed so as to penetrate in the wall thickness direction.

The temperature / humidity exchange cells 21, the unreacted oxidant gas separators 22 and the already-reacted oxidant gas separators 23 described above are alternately arranged as shown in FIG. It is arranged between two horizontal end plates 32.

The end plate 37 is in contact with the side surface of the body of the temperature / humidity exchange means, and has an unreacted oxidant gas inlet 41 so that the oxidant gas can be introduced, and an already reacted oxidant so that the oxidant gas can be discharged. A gas outlet 42 is formed.

In the first embodiment, the temperature / humidity exchange cell 21
Are stacked so that they are substantially perpendicular to the parallel juxtaposition direction (stacking direction) of the single cell batteries 2, that is, parallel to the horizontal direction, and the side surface of the temperature / humidity exchange means 20 is the end surface of the fuel cell stack 1 in the parallel juxtaposition direction. It is arranged so as to be in contact with the (lamination surface). The unreacted oxidant gas separator 22 and the unreacted oxidant gas separator 23 (not shown) in the temperature / humidity exchange cell 21 are connected to the unreacted oxidant gas supply manifold 2.
7 and the already-reacted oxidant gas exhaust manifold 31 are provided, and the unreacted oxidant exhaust manifold 28 conventionally provided
Also, the already-reacted oxidant supply manifold 36 is omitted.

In FIG. 2, the unreacted oxidant gas is supplied from the oxidant gas inlet 41 provided on the side surface of the end plate 37 of the temperature / humidity exchange means 20, and the temperature / humidity exchange means 2 is supplied.
It is distributed to each temperature / humidity exchange cell 21 by the unreacted oxidant gas supply manifold 27 which communicates with the upper and lower sides of 0. In the temperature / humidity exchange cell 21, the unreacted oxidant gas separator 22
A part of the water contained in the reacted oxidant gas is added through the gas flow path formed on the surface of the.

In FIG. 3, the unreacted oxidant gas to which water has been added passes through the cell oxidant gas supply manifold 12 of the fuel cell stack 1 vertically and is supplied to each single cell battery 2.

The reacted oxidant gas discharged from the single cell battery 2 is collected through the cell oxidant gas discharge manifold 13 of the fuel cell stack 1 and supplied to the temperature / humidity exchange means 20.

As shown in the flow of the oxidant gas in FIG. 9, the unreacted oxidant gas distributed to each unreacted oxidant gas separator 22 by the unreacted oxidant gas supply manifold 27 is after the addition of water. , Is directly supplied to the battery oxidant gas supply manifold 12. As a result, since there is no pressure loss due to the merge loss, it is possible to reduce the overall pressure loss. Similarly, the already-reacted oxidant gas recovered by the battery oxidant gas discharge manifold 13 is directly supplied to each already-reacted oxidant gas separator 23, and there is no pressure loss due to branch loss, so that the overall pressure loss can be reduced. It will be possible.

This is also clear from the following experimental results. A conventional fuel cell system with an output of 10 kW and a fuel cell system of the present embodiment were prototyped, and an output of 10 kW was obtained.
Corresponding air was supplied as an oxidant gas, and the pressure loss of each air was measured. As a result, the pressure loss was 30 kPa in the conventional fuel cell system, but it was reduced to 25 kPa in this embodiment.

As described above, the temperature / humidity exchange cells 21 composed of the temperature / humidity exchange membrane 24 and the seal packing 25 are horizontally stacked at a substantially right angle with respect to the parallel juxtaposition direction of each single cell battery 2, and thus the conventional arrangement is provided. The unreacted oxidant gas discharge manifold 28 and the like that have been used can be omitted, and the pressure loss of the oxidant gas can be reduced.

The fuel inlet 43 of the fuel cell stack 1
The fuel input from the fuel supply manifold 62, the fuel discharge manifold 64, and the fuel outlet 44, and the coolant is cooled through the coolant inlet (not shown) and the cooling water manifolds 61 and 63. Discharging from the agent outlet 45 is similar to the above-described conventional technique.

10 to 12 are views for explaining the second embodiment of the polymer electrolyte fuel cell system according to the present invention. FIG. 10 is a perspective view showing the outline of the fuel cell system according to the present invention. The upper surface of the fuel cell stack 1, that is, the direction in which the single cell batteries 2 are arranged side by side, is configured in substantially the same manner as in the first embodiment. On the plane orthogonal to
Temperature / humidity exchange means 20 having substantially the same configuration as that of the above embodiment.
The point that is provided is different from the first embodiment.

The temperature / humidity exchanging means 20 comprises a temperature / humidity exchanging cell 21 having an unreacted oxidant gas separator 22 and a reacted oxidant gas separator 23 between two horizontally arranged horizontal end plates 32. They are laminated alternately. Each temperature / humidity exchange cell 21 is composed of a temperature / humidity exchange membrane 24 made of a water-retaining porous body and a seal packing 25 provided so as to sandwich the membrane. The water contained in the reacted oxidant gas is added to the unreacted oxidant gas by bringing them into contact with each other through the exchange membrane 24.

In the fuel cell stack 1, a plurality of single cell batteries 2 each composed of a membrane electrode assembly 3 and a separator 5 are arranged side by side in a horizontal direction, and end plates 30 are arranged at both ends of the arrangement direction, and these are arranged. It is an integrated one. As shown in FIG. 11, the separator 5 is formed with a battery oxidant gas supply manifold 12A and a battery oxidant gas discharge manifold 13A in the vertical direction on the left and right peripheral portions of the plate surface of the separator 5, respectively. Besides, the oxidant gas flow channel 60, the cooling water manifolds 61 and 63, the fuel supply manifold 62, and the fuel discharge manifold 64 are provided on the plate surface of the plate body.
Is the same as that of the first embodiment.

FIG. 12 is a view for explaining the unreacted oxidant gas separator 22 of the temperature / humidity exchange cell 21 of FIG. The unreacted oxidant gas separator 22 has an oxidant gas flow path 15 formed diagonally in the center of the plate body.
An unreacted oxidant gas supply manifold 27, an unreacted oxidant gas discharge manifold 28, a reacted oxidant gas supply manifold 36, and a reacted oxidant gas discharge manifold 31 are provided.

Unreacted oxidant gas supply manifold 27
Is in communication with the oxidant gas inlet 41, is supplied with oxidant gas, and flows through the oxidant gas flow path 15 to the unreacted oxidant gas discharge manifold 28 in a diagonal direction.

FIG. 11 is a sectional view taken along the line EE of FIG. A fuel supply manifold 62, a fuel discharge manifold 64, cooling water manifolds 61, 63, a cell oxidant gas supply manifold 12A, and a cell oxidant gas discharge manifold 13A are provided in the separator 5 that constitutes the fuel cell stack. The fuel supply manifold 62 and the fuel discharge manifold 64 are in communication with a fuel gas passage on the back surface of the separator 5 (not shown), and the fuel gas is supplied.

Battery oxidant gas supply manifold 12A,
The battery oxidant gas discharge manifold 13A communicates with the oxidant gas flow channel 60, and the oxidant gas is supplied to the membrane electrode assembly 3
Is supplied to. Battery oxidant gas supply manifold 12
A, the battery oxidant gas discharge manifold 13A communicates with the unreacted oxidant gas discharge manifold 28 and the already-reacted oxidant gas supply manifold 36 of the temperature / humidity exchange means 20 stacked on the upper part, respectively, and the temperature / humidity exchange means 20
The unreacted oxidant gas added with water is supplied to the fuel cell stack 1, and the reacted oxidant gas discharged from the fuel cell stack 1 is supplied to the temperature / humidity exchange means 20.

FIG. 13 is a diagram for explaining the flow of the oxidant gas in the polymer electrolyte fuel cell system of the second embodiment. As shown in this figure, the unreacted oxidant gas passes through the unreacted oxidant gas discharge manifold 28 and is introduced from the side of the communicating cell oxidant gas supply manifold 12. Therefore, the right half of the communicating portion is supplied to each single cell battery 2 without causing merging and branching loss, so that the pressure loss can be reduced. Similarly, even in the flow of the reacted oxidant gas, the right half of the communicating portion is discharged from each single cell battery 2 without causing merge and branch loss and is supplied to the reacted oxidant gas supply manifold 36. Therefore, it is possible to reduce the pressure loss.

This is also apparent from the following.
A conventional fuel cell system with an output of 10 kW and a fuel cell system according to the second embodiment were prototyped, air corresponding to an output of 10 kW was supplied as an oxidant gas, and the pressure loss of each air was measured. 30 kPa in conventional fuel cell system
Pressure loss of 23 kPa in the second embodiment.
The pressure loss was reduced.

In this way, a plurality of single cell batteries 2 are arranged on the horizontal plane.
By stacking the temperature / humidity exchange cells 21 vertically on the upper surface of the fuel cell stack 1, the oxidant gas can be supplied / discharged in the cross-sectional direction of the fuel cell stack 1, resulting in pressure loss of the oxidant gas. Can be reduced.

14 to 16 are views for explaining a third embodiment of the polymer electrolyte fuel cell system according to the present invention. FIG. 14 is a perspective view showing the outline of the fuel cell system according to the present invention. In the fuel cell system, a plurality of single cell batteries 2 having the same shape are juxtaposed in parallel and integrally formed, and a reacted oxidant gas and an unreacted oxidant gas are passed through a temperature / humidity exchange membrane 24. The temperature / humidity exchange means 20 is formed by arranging a plurality of temperature / humidity exchange cells 21 which are brought into contact with each other and add the water contained in the already-reacted oxidant gas to the unreacted oxidant gas in parallel. Temperature and humidity exchange cell 2
1 is composed of an unreacted oxidant gas separator, a water-retaining porous body (not shown), and a reacted oxidant gas separator 22 (not shown).

In the third embodiment, the temperature / humidity exchange means 20.
The parallel juxtaposition direction of the fuel cell stack 1 is parallel to the parallel juxtaposition direction of the fuel cell stack 1, that is, one side surface of the temperature / humidity exchange cells 21 having the same shape is perpendicular to the parallel juxtaposition direction. The side surfaces of the temperature / humidity exchanging means 20 were arranged so as to be in contact with the side surface of the fuel cell stack 1 so as to be juxtaposed substantially parallel to the one side surface of the right angle.

FIG. 15 is a sectional view taken along line FF of FIG. 14, and FIG. 16 is a sectional view taken along line GG of FIG. The separator 5 that constitutes the fuel cell stack 1 is provided with a fuel supply manifold 62, a fuel discharge manifold 64, cooling water manifolds 61 and 63, a cell oxidant gas supply manifold 12A, and a cell oxidant gas discharge manifold 13A. The fuel supply manifold 62 and the fuel discharge manifold 64 are in communication with a fuel gas passage (not shown) on the back surface of the separator 5 and are supplied with fuel gas.

Battery oxidant gas supply manifold 12A,
The battery oxidant gas discharge manifold 13A communicates with the oxidant gas flow channel 60, and the oxidant gas is supplied to the membrane electrode assembly 3
Is supplied to. Battery oxidant gas supply manifold 12
A, the battery oxidant gas discharge manifold 13A communicates with the unreacted oxidant gas separator 22 and the already reacted oxidant gas separator 23 of the temperature / humidity exchange means 20 arranged at the upper part, respectively, and is connected to the temperature / humidity exchange means 20. The unreacted oxidant gas added with water is supplied to the fuel cell stack 1, and the reacted oxidant gas discharged from the fuel cell stack 1 is supplied to the temperature / humidity exchange means 20.

The unreacted oxidant gas separator 22 is provided with an oxidant gas flow channel 60 at the center of the plate, an unreacted oxidant gas supply manifold 27, and an already-reacted oxidant gas discharge manifold 31. The unreacted oxidant gas discharge manifold and the already-reacted oxidant gas supply manifold are omitted. The unreacted oxidant gas supply manifold 27 is
The oxidant gas is communicated with the oxidant gas inlet 41, and the oxidant gas is supplied and flows in a diagonal direction to the unreacted oxidant gas discharge manifold through the oxidant gas flow path 15 formed on the plate surface.

FIG. 17 is a diagram for explaining the flow of the oxidizing gas in the polymer electrolyte fuel cell system according to the third embodiment. As is clear from this figure, the unreacted oxidant gas passes through the unreacted oxidant gas supply manifold 27 of the unreacted oxidant gas separator 22 and is introduced from the side of the communicating cell oxidant gas supply manifold 12A. It
For this reason, the pressure loss can be reduced because the single cell batteries 2 are supplied without merging or branching loss.

Similarly, in the flow of the already-reacted oxidant gas, the single-cell battery 2 is introduced into the already-reacted oxidant gas exhaust manifold 31 of the already-reacted oxidant gas separator 23 through the battery oxidant gas exhaust manifold 13A. To be done. Therefore, the pressure loss can be reduced because it is discharged from each single cell battery without being merged and branched and is supplied to the reacted oxidant gas separator 23.

A conventional fuel cell system with an output of 10 kW and a fuel cell system according to the third embodiment of the present invention were prototyped,
Air having an output of 10 kW was supplied as an oxidant gas, and the pressure loss of each air was measured. In the conventional fuel cell system, the pressure loss was 30 kPa, but in the present embodiment, it was reduced to 23 kPa.

As described above, the temperature / humidity exchange cells 21 are juxtaposed so as to be parallel to the parallel juxtaposition direction of the single cell batteries 2, and one side surface of the temperature / humidity exchange means 20 substantially perpendicular to the parallel juxtaposition direction and the fuel cell. By abutting (matching) one side surface that is substantially perpendicular to the parallel juxtaposition direction of the stack 1, the unreacted oxidant gas discharge manifold and the already-reacted oxidant gas supply manifold can be omitted, and the oxidant gas is oxidized by the battery. Agent gas supply manifold 12A, battery oxidant gas discharge manifold 1
The flow can be made parallel to the cross section of 3A, and the pressure loss of the oxidant gas can be reduced.

18 to 20 are views for explaining a fourth embodiment of the polymer electrolyte fuel cell system according to the present invention. 18 is a perspective view showing an outline of a fuel cell system according to the present invention, FIG. 19 is a cross-sectional view of FIG. 18, and FIG. 20 is an unreacted oxidant gas separator and a reacted oxidant gas separator of FIG. It is a figure for explaining.

In the fuel cell system, a plurality of single cell batteries having the same shape are arranged in parallel in parallel and integrated, and the fuel cell stack 1 and the reacted oxidant gas and unreacted oxidant gas are passed through a water retentive porous body. A plurality of temperature / humidity exchange cells 21 of the same shape that are brought into contact with each other to add the water contained in the already-reacted oxidant gas to the unreacted oxidant gas are arranged in parallel in parallel and are constituted by an integrated temperature / humidity exchange means 20. The temperature / humidity exchange cell 21 is composed of an unreacted oxidant gas separator, a water-retaining porous body (not shown), and a reacted oxidant gas separator (not shown).

In this embodiment, one temperature / humidity exchange means 20 is provided for four fuel cell stacks 1, and the temperature / humidity exchange cells 21 are arranged at right angles to the parallel juxtaposition direction of the single cell batteries 2.
Specifically, it is arranged such that one side surface of the single cell battery 2 that is substantially perpendicular to the parallel juxtaposition direction and one side surface of the temperature / humidity exchange cell 21 are in contact (coincidence).

The unreacted oxidant gas separator 22 includes an oxidant gas flow passage 15 at the center of the plate surface, an unreacted oxidant gas supply manifold 27, a reacted oxidant gas discharge manifold 31, and an unreacted oxidant gas. An exhaust manifold 28 and a reacted oxidant gas supply manifold 36 are provided.

Unreacted oxidant gas supply manifold 27
Communicate with the oxidant gas inlet 41, the oxidant gas is supplied to each unreacted oxidant gas separator 22 through the unreacted oxidant gas supply manifold 27, and passes through the oxidant gas flow path 15 to obtain moisture. After being added, it flows diagonally to the unreacted oxidant gas exhaust manifold 28.

A notch is provided in the unreacted oxidant gas discharge manifold 28 of the unreacted oxidant gas separator in some of the temperature / humidity exchange cells 21, and a notch is provided through the communication duct 66. It communicates with the cell oxidant gas supply manifold 12 of the fuel cell stack 1.

In the already-reacted oxidant gas separator 23, the gas flow path 15 at the center of the plate surface, the unreacted oxidant gas supply manifold 27, the already-reacted oxidant gas exhaust manifold 31, and the unreacted oxidant gas exhaust. A manifold 28 and a reacted oxidant gas supply manifold 36 are provided.

Reacted oxidant gas exhaust manifold 31
Communicate with the oxidant gas outlet 42, and the oxidant gas is collected and discharged from each of the reacted oxidant gas separators 23 via the reacted oxidant gas discharge manifold 31.

Of the plurality of temperature / humidity exchange cells 21, a part of the temperature / humidity exchange cells 21 that has already reacted with the oxidant gas separator 23
A cutout is provided in the already-reacted oxidant gas supply manifold 36 and communicates with the cell oxidant gas discharge manifold 13 of the fuel cell stack 1 through a communication duct 66.

The unreacted oxidant gas supply manifold 27 and the unreacted oxidant gas discharge manifold 28 of the temperature / humidity exchange means 20 not only have a function of distributing / recovering the oxidant gas to each temperature / humidity exchange cell 21. It also has a function of a distribution manifold to the oxidant gas flow paths 15 of the four fuel cell stacks 1. Therefore, it is not necessary to provide a distribution manifold for each fuel cell stack 1, and it is possible to reduce pressure loss.

Similarly, the already-reacted oxidant gas supply manifold 36 and the already-reacted oxidant gas discharge manifold 31 have not only a function of distributing and recovering the oxidant gas to each temperature / humidity exchange cell 21, but also four The fuel cell stack 1 also has the function of a manifold for the oxidant gas flow passages. Therefore, it is not necessary to provide an assembly manifold for each fuel cell stack 1, and it is possible to reduce pressure loss.

This is also apparent from the following.
A fuel cell system using four conventional fuel cell systems with an output of 10 kW and a fuel cell system of the present embodiment were prototyped, air corresponding to an output of 40 kW was supplied as an oxidant gas, and the pressure loss of each air was measured. . The pressure loss was 35 kPa in the conventional fuel cell system, but it could be reduced to 28 kPa in the present embodiment.

In this way, a plurality of fuel cell stacks 1
One temperature / humidity exchange means 20 is arranged, and the temperature / humidity exchange cells 21 are stacked so as to be perpendicular to the parallel juxtaposition direction of the single cell batteries 2, and the side surface of the temperature / humidity exchange means 20 and the fuel cell stack 1 are stacked. By matching the surfaces of the fuel cell stack 1
The oxidant gas collecting and distributing manifold can be omitted, and the pressure loss of the oxidant gas can be reduced.

[0081]

According to the present invention described above, it is possible to reduce the pressure loss of the reaction gas in the fuel cell system in which the unreacted gas is humidified by using the already-reacted gas through the water-retaining porous material. It is possible to provide a polymer electrolyte fuel cell system that can be manufactured.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining a first embodiment of a polymer electrolyte fuel cell system of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

4 is a cross-sectional view taken along the line CC of FIG.

5 is a cross-sectional view taken along line D-D in FIG.

FIG. 6 is a cross-sectional view showing in detail the temperature and humidity exchange means of FIG.

7 is a cross-sectional view showing in detail the temperature and humidity exchange means of FIG.

FIG. 8 is a front view for explaining a separator of the single cell battery of FIG.

FIG. 9 is a diagram for explaining the flow of an oxidant gas in the polymer electrolyte fuel cell system according to the first embodiment.

FIG. 10 is a perspective view for explaining a second embodiment of the polymer electrolyte fuel cell system of the present invention.

11 is a cross-sectional view taken along the line EE of FIG.

FIG. 12 is a view for explaining the unreacted oxidant gas separator of FIGS. 6 and 7.

FIG. 13 is a view for explaining the flow of an oxidant gas in the polymer electrolyte fuel cell system according to the second embodiment.

FIG. 14 is a perspective view for explaining a third embodiment of the polymer electrolyte fuel cell system of the present invention.

FIG. 15 is a sectional view taken along line FF of FIG.

16 is a sectional view taken along line GG of FIG.

FIG. 17 is a view for explaining the flow of an oxidant gas in the polymer electrolyte fuel cell system according to the third embodiment.

FIG. 18 is a perspective view for explaining a fourth embodiment of the polymer electrolyte fuel cell system of the present invention.

FIG. 19 is a cross-sectional view of FIG.

20 is a cross-sectional view for explaining the unreacted oxidant gas separator and the already reacted oxidant gas separator of FIG.

FIG. 21 is a vertical cross-sectional view showing an example of a conventional polymer electrolyte fuel cell system.

22 is a diagram for explaining the flow of the oxidant gas in FIG.

[Explanation of symbols]

1. Polymer electrolyte fuel cell stack 2 ... Single cell battery 3 ... Membrane electrode complex 4 ... Seal packing 5 ... Separator 6 ... Polymer electrolyte membrane 7 ... Fuel pole 8 ... Oxidizer pole 12 ... Battery oxidant gas supply manifold 12A ... Battery oxidant gas supply manifold 13 ... Battery oxidant gas exhaust manifold 13A ... Battery oxidant gas exhaust manifold 15 ... Oxidant gas flow path 20 ... Temperature and humidity exchange means 21 ... Temperature and humidity exchange cell 22 ... Unreacted oxidant gas separator 22a ... Gas flow path 23 ... Reacted oxidant gas separator 23a ... Gas flow path 24 ... Temperature and humidity exchange membrane 25 ... Seal packing 27 ... Unreacted oxidant gas supply manifold 28 ... Unreacted oxidant gas exhaust manifold 30 ... End plate 31 ... Reacted oxidant gas exhaust manifold 32 ... Horizontal end plate 35 ... Reacted oxidant gas supply manifold 36 ... Reacted oxidant gas supply manifold 37 ... End plate 41 ... Unreacted oxidant gas inlet 42 ... Outlet of already reacted oxidant gas 42 ... Oxidant gas outlet 43 ... Fuel inlet 44 ... Fuel outlet 45 ... Coolant outlet 51 ... Water-retaining porous body 51 ... Porous body 52 ... Reacted oxidant gas 53 ... Unreacted oxidant gas 60 ... Oxidant gas flow path 61 ... Cooling water manifold 62 ... Fuel supply manifold 63 ... Cooling water manifold 64 ... Fuel discharge manifold 66 ... Communication duct

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kahiro Taniyama             2-4 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa               Toshiba Keihin Office (72) Inventor Michiro Hori             2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa             Ceremony Company Toshiba Hamakawasaki Factory F-term (reference) 5H026 AA06 CC08                 5H027 AA06 BA01 BA17 BC11 CC06

Claims (7)

[Claims] 1. A solid polymer type fuel cell stack in which a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte are juxtaposed in parallel and integrated, and a reacted gas which has passed through a reaction part of the fuel cell stack. And a temperature / humidity exchange means formed by stacking and integrating a plurality of temperature / humidity exchange cells of the same shape for exchanging heat and moisture with the unreacted gas before passing through the reaction part of the fuel cell stack. In the polymer fuel cell system, the fuel cell stack and the temperature / humidity exchange means are arranged in contact with each other so that the stacking direction of the temperature / humidity exchange cells is substantially perpendicular to the parallel juxtaposition direction of the single cell cells. A polymer electrolyte fuel cell system characterized by the above. 2. The polymer electrolyte fuel cell stack is arranged so that one end face in the parallel juxtaposition direction and one end face in the stacking direction of the temperature / humidity exchange means are in contact with each other. The polymer electrolyte fuel cell system according to item 1. 3. The polymer electrolyte fuel cell stack is arranged such that one side surface in the parallel juxtaposition direction and one end surface in the stacking direction of the temperature / humidity exchanging means are in contact with each other. The polymer electrolyte fuel cell system according to item 1. 4. A solid polymer type fuel cell stack in which a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte are juxtaposed in parallel and integrated, and an already reacted gas which has passed through a reaction part of the fuel cell stack. And a temperature / humidity exchange means in which a plurality of temperature / humidity exchange cells of the same shape for exchanging heat and moisture with the unreacted gas before passing through the reaction part of the fuel cell stack are arranged in parallel and integrated. In the solid polymer fuel cell system, the solid polymer fuel cell system is arranged so that the parallel juxtaposition directions of the temperature / humidity exchange cells and the parallel juxtaposition directions of the single cell batteries are in contact with each other. . 5. The polymer electrolyte fuel cell stack,
5. The polymer electrolyte fuel cell system according to claim 2, wherein the temperature / humidity exchange means is integrated via a plate having a flow hole for a reaction gas or a cooling medium. . 6. A solid polymer type fuel cell stack comprising a plurality of single cell batteries of the same shape having a solid polymer membrane as an electrolyte, which are arranged in parallel in parallel and integrated with each other to form an integral body and to form the fuel. A plurality of temperature-humidity exchange cells of the same shape that exchange heat and moisture between the already-reacted gas that has passed through the reaction section of the cell stack and the unreacted gas that has not yet passed through the reaction section of the fuel cell stack are arranged in parallel and integrated. In the polymer electrolyte fuel cell system including the temperature and humidity exchange means, the parallel juxtaposition direction of the temperature and humidity exchange cells is substantially perpendicular to the parallel juxtaposition direction of the single cell battery, and A polymer electrolyte fuel cell system, wherein the polymer electrolyte fuel cell stack is arranged so as to be substantially parallel to the parallel arrangement direction of the polymer electrolyte fuel cell stack. 7. The polymer electrolyte fuel cell stack is arranged such that one end face in the parallel juxtaposition direction and one side face in the parallel juxtaposition direction of the temperature / humidity exchange means are in contact with each other. Item 7. A polymer electrolyte fuel cell system according to item 6.