JPH1032012A - Phosphoric acid fuel cell and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably operate a fuel cell for a long time by improving the distribution of the amount of hydrogen in a fuel gas within the surface of a unit cell and the amount of oxygen in air. SOLUTION: A unit cell 1 is constituted by interposing a matrix 4 containing phosphoric acid between an air electrode 2 comprising an air electrode base material 2b having a plurality of air flow grooves 3 arranged in parallel and an air electrode catalyst layer 2a and a fuel electrode 3 comprising a fuel electrode base material 5b having a plurality of fuel gas flow grooves 6A arranged in parallel, so as to perpendicularly cross to the air flow groove 3, a fuel electrode catalyst layer 5a, and a reservoir plate 5c, and unit cells are alternately stacked with a separating plate 7 to constitute a fuel cell stacked body. A plurality of fuel gas flow grooves 6A are constituted with a plurality of flow grooves in which the width of the flow path is almost the same, and the depth of the flow path is made gradually deeper toward the air inlet side and shallower toward the air outlet side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a fuel cell stack of a phosphoric acid type fuel cell and a method of manufacturing the same, and more particularly, to a structure of a reaction gas passage and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a phosphoric acid type fuel cell, a single cell is formed by sandwiching a matrix containing phosphoric acid between a fuel electrode and an air electrode, and the single cell is alternately arranged with a separate plate made of a gas impermeable material. To form a fuel cell stack, and a fuel gas is supplied to the fuel electrode and air is supplied to the air electrode to generate power.

[0003] Fig. 11 is a basic configuration diagram of a single cell of a phosphoric acid type fuel cell conventionally used. The upper left diagram is a plan view as viewed from the stacking direction, and the upper right diagram is a side view as viewed from the air outlet side. The figure and the lower figure are side views seen from the fuel gas inlet side. As shown in the figure, a single cell 1 in the form of a rectangular flat plate is composed of a matrix 4 containing phosphoric acid, an air electrode 2 and a fuel electrode 5 interposed therebetween, and a separate material made of a gas impermeable material. The fuel cell stack is formed by interposing the plates 7 and alternately stacking them while maintaining airtightness. Air electrode 2
Is composed of an air electrode catalyst layer 2a and a ribbed air electrode base material 2b made of a porous material supporting the air electrode catalyst layer 2a.
Is composed of a fuel electrode catalyst layer 5a, a fuel electrode base material 5b with a rib made of a porous material supporting the same, and a reservoir plate 5c made of a porous material holding phosphoric acid for replenishment. Further, the air electrode base 2b is provided with a plurality of air flow grooves 3 having the same cross-sectional shape, which are arranged in parallel and communicate with each other from one side to the opposite side. Is provided with a plurality of fuel gas flow grooves 6 arranged in parallel and having the same cross-sectional shape and communicating in a direction orthogonal to the flow direction of the air flow grooves 3.

Accordingly, when air is supplied to the plurality of air flow grooves 3 and the fuel gas is separately supplied to the plurality of fuel gas flow grooves 6 from the side surface of the fuel cell stack of the present structure, the air electrode base material is provided. 2b and the fuel electrode base material 5b to reach the air electrode catalyst layer 2a and the fuel electrode catalyst layer 5a,
An electrochemical reaction occurs, and electric energy is extracted to the outside.

[0005]

The above-mentioned power generation reaction is a reaction in which oxygen in air reacts with hydrogen in fuel gas to generate water and electrons. Therefore, since the air sent to the air flow groove 3 consumes oxygen in the plane and is discharged, the oxygen concentration at the outlet is lower than that at the inlet. Similarly, the fuel gas sent to the fuel gas flow groove 6 also consumes hydrogen in the plane, so that the hydrogen concentration at the outlet portion is greatly reduced. Furthermore, the oxygen consumption of the air sent to the air flow groove 3 varies not only with its own oxygen concentration but also with the amount of hydrogen in the fuel gas. Then the oxygen consumption is also reduced. Similarly, the hydrogen consumption of the fuel gas sent to the fuel gas flow groove 6 is large in the portion with a large amount of oxygen, and is small in the portion with a small amount of oxygen.

Accordingly, as shown in FIG. 11, in a configuration in which air is divided and supplied to the plurality of air flow grooves 3 and fuel gas is divided and supplied to the plurality of fuel gas flow grooves 6, each air flow groove is provided. Although the amount of oxygen in the air supplied to the flow groove 3 is the same, a large amount of oxygen is consumed near the inlet of the air flow groove 3 arranged on the upstream side of the fuel gas.
The oxygen concentration on the downstream side is greatly reduced, the amount of oxygen is insufficient, and there is a risk that the constituent members made of the carbon material are corroded. Similarly, a large amount of oxygen is consumed in the vicinity of the inlet also in the fuel gas flow groove 6 arranged on the upstream side of the air, so that the concentration of hydrogen on the downstream side is significantly reduced, the amount of hydrogen is insufficient, and the constituent members are reduced. Corrosion occurs, making it difficult to maintain stable operation.

An object of the present invention is to solve the above-mentioned disadvantages of the prior art and to improve the distribution of the amount of hydrogen in the flowing fuel gas or the amount of oxygen in the flowing air so as to be stable for a long time. It is an object of the present invention to provide a configuration of a phosphoric acid type fuel cell which can be operated in a vacuum and a method for manufacturing the same.

[0008]

In order to achieve the above object, according to the present invention, a rectangular flat plate-shaped single cell having a phosphoric acid-containing matrix and a fuel electrode and an air electrode sandwiching the matrix is provided. A gas impermeable separate plate is interposed,
A fuel cell stack is formed by stacking a plurality of layers, and the fuel gas flows through a plurality of fuel gas passages provided in parallel with the fuel electrode or the separate plate in communication with the side surface opposite to the side surface, and the air electrode Alternatively, phosphoric acid generates electric power by an electrochemical reaction by flowing air through a plurality of air passages provided in parallel with the fuel gas passages in a direction perpendicular to the fuel gas passages to a side surface opposite to the side surface of the separate plate. (1) The plurality of fuel gas passages having the same width, the passage having a depth substantially closer to the air inlet side, and being shallower toward the air outlet side. Alternatively, the plurality of air passages are constituted by passages having substantially the same width, the depth of the passage being closer to the fuel gas inlet side, and being shallower toward the fuel gas outlet side. It shall be.

(2) Alternatively, the plurality of fuel gas passages may have the same width, the depth of the passage being closer to the air inlet side, and shallower toward the air outlet side. And the plurality of air passages are formed of passages having substantially the same width, the depth of the passage being closer to the fuel gas inlet side, and shallower to the fuel gas outlet side. It shall be. (3) In the phosphoric acid type fuel cell according to (1), the plurality of fuel gas passages have substantially the same width, and the depth of the passage is deeper on the air inlet side and shallower on the air outlet side. In the structure composed of a plurality of flow paths, the constituent member provided with the fuel gas flow path is formed from a member that is thicker on the air inlet side and thinner on the air outlet side, and the constituent member provided with the air flow path. It is formed from a member that is thinner on the air inlet side and thicker on the air outlet side, and is formed such that the sum of the thicknesses of the two constituent members is substantially the same in the plane.

(4) The phosphoric acid type fuel cell of (1),
A plurality of air passages, the width of the passage is substantially the same, the depth of the passage is closer to the fuel gas inlet side, the shallower passage closer to the fuel gas outlet side, the air passage is provided with an air passage A member that is thicker on the fuel gas inlet side and thinner on the fuel gas outlet side, and a member provided with a fuel gas passage is thinner on the fuel gas inlet side and thicker on the fuel gas outlet side. And the thicknesses of the two components are made substantially the same in the plane.

(5) In the phosphoric acid type fuel cell of the above (1) to (4), the fuel gas passage or the air passage composed of a plurality of passages having different depths is similar. And the deepest portions of the plurality of flow channels are all located on the same plane. (6) In the phosphoric acid type fuel cell configured as described in (5) above, the fuel gas flow path or the air flow path composed of a plurality of flow paths having different depths is formed by multiple rotary blades. Using a processing machine equipped with, the angle between the center of the rotation axis of the rotary blade and the upper surface of the work table on which the workpiece is mounted is set to a predetermined value, and the rotary blade is moved by equilibrium movement to process and form. I do.

According to the above (1), the plurality of fuel gas passages are substantially the same in width, and the depth of the passage is greater toward the air inlet side and shallower toward the air outlet side. In the configuration formed by the flow passages, the cross-sectional area of the fuel gas flow passage on the air inlet side is larger than the flow cross-sectional area of the fuel gas flow passage on the air outlet side. In proportion, a relatively large amount of fuel gas, and thus a relatively large amount of hydrogen, is supplied to the fuel gas passage on the air inlet side where the consumption of hydrogen in the fuel gas is relatively large. A situation in which the amount of hydrogen is insufficient on the downstream side as in the related art is avoided, and corrosion of components is prevented.

[0013] Further, in the case where the plurality of air passages are constituted by passages having substantially the same width, the depth of the passage being deeper on the fuel gas inlet side and shallower on the fuel gas outlet side. ,
Similarly, a relatively large amount of air, and thus a relatively large amount of oxygen, is supplied to the air passage on the fuel gas inlet side where the consumption of oxygen in the air is relatively large. A shortage of oxygen on the downstream side is avoided, and corrosion of the components is prevented.

According to the above (2), the shortage of hydrogen on the downstream side of the fuel gas passage and the shortage of oxygen on the downstream side of the air passage are avoided. Corrosion of the member is prevented. According to the above (3), shortage of the amount of hydrogen on the downstream side of the fuel gas passage is avoided, and not only corrosion of the components is prevented, but also the components of the fuel electrode are provided with fuel. Even in the case where the gas passage is formed, the thickness of the remaining wall can be made substantially constant, so that the gas diffusion in the constituent member can be uniform in the plane. In addition, according to the above (4), shortage of oxygen on the downstream side of the air passage is avoided, so that not only corrosion of the components is prevented but also the air flow to the components of the air electrode is prevented. Even in the case where the passage is formed, the gas diffusion in the constituent members can be made uniform in the plane.

Further, if the above (5) is satisfied,
For example, by using a method such as the above (6),
It can be easily processed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> FIG. 1 is a basic structural diagram of a single cell showing a first embodiment of the phosphoric acid type fuel cell of the present invention. As in the conventional example shown in FIG. 11, the upper left figure is a plan view seen from the laminating direction, the upper right figure is a side view seen from the air outlet side, and the lower figure is a side view seen from the fuel gas inlet side. .

The difference between the present embodiment and the conventional example is that the fuel electrode 5
In the fuel electrode base layer 5b supporting the fuel electrode catalyst layer 5a. In contrast to the conventional example, which is constituted by a plurality of fuel gas flow grooves 6 having the same flow path width and the same depth, in the present embodiment, the fuel gas flow grooves 6 have the same flow path width and air is supplied from the air outlet side. A plurality of fuel gas flow grooves 6 in which the depth of the grooves increases toward the inlet side
A. In this configuration, since the flow path cross-sectional area increases from the air outlet side to the air inlet side, a larger amount of fuel gas flows through the fuel gas flow groove 6A closer to the air inlet side. Therefore, even if a large amount of hydrogen is consumed on the upstream side of the fuel gas flow groove 6A near the air inlet side, sufficient fuel is contained in the downstream fuel gas. There is no danger of corrosion. Also, the fuel gas flow groove 6A near the air outlet side
Although the amount of fuel gas flowing through the fuel cell is reduced as compared with the conventional example, the amount of oxygen contained in the air at the air outlet side is small, and the consumption of hydrogen is also small. Absent.

It is to be noted that the plurality of air flow grooves have the same flow path width, and the plurality of gas flow grooves have a depth that becomes deeper as going from the fuel gas outlet side to the fuel gas inlet side. Then, the lack of oxygen on the downstream side of the air flow groove on the fuel gas inlet side, which is observed in the conventional example, can be easily analogized from the above-described first embodiment. Description is omitted.

<Second Embodiment> FIG. 2 is a basic structural diagram of a single cell showing a second embodiment of the phosphoric acid fuel cell of the present invention. The feature of this embodiment is that a plurality of fuel gas flow grooves 6A formed in the fuel electrode base material 5b have the same flow path width as in the first embodiment, and go from the air outlet side to the air inlet side. It is composed of a plurality of gas flow grooves, the depth of which increases according to
Further, a plurality of air flow grooves 3A provided on the air electrode base material 2b of the air electrode 2 have the same flow path width, and the depth of the grooves increases from the fuel gas outlet side to the fuel gas inlet side. The point is that it is composed of gas flow grooves.

In this configuration, as in the first embodiment, sufficient hydrogen is also contained in the fuel gas on the downstream side of the fuel gas flow groove 6A on the air inlet side, and the downstream side of the air flow groove on the fuel gas inlet side is sufficient. Since sufficient oxygen is also contained in the air on the side, corrosion of the constituent members is effectively prevented. <Third Embodiment> FIG. 3 is a basic structural view of a single cell showing a third embodiment of the phosphoric acid fuel cell of the present invention.

The feature of this embodiment is that the air electrode 2 comprises an air electrode catalyst layer 2a, an air electrode base material 2d and a reservoir plate 2e having ribs for forming grooves, and the fuel electrode 5 comprises a fuel electrode catalyst layer 5a, In a fuel electrode base 5d and a reservoir plate 5e having ribs for forming grooves, the reservoir plate 2e has the same flow path width, and the depth of the groove increases from the fuel gas outlet to the fuel gas inlet. Are provided with a plurality of air flow grooves 3A, and the reservoir plate 5e has the same flow path width, and a plurality of fuel gas flow grooves whose grooves become deeper from the air outlet side to the air inlet side. 6A is provided.

In this configuration, as in the second embodiment,
The fuel gas on the downstream side of the fuel gas flow groove 6A on the air inlet side also contains sufficient hydrogen, and the air flow groove 3 on the fuel gas inlet side also has sufficient hydrogen.
The air downstream of A also contains sufficient oxygen. <Fourth Embodiment> FIG. 4 is a basic structural diagram of a single cell showing a fourth embodiment of the phosphoric acid fuel cell of the present invention.

This embodiment is characterized in that a separate plate 7A having a rib forming an air flow groove 3A on one main surface and a rib forming a fuel gas flow groove 6A on the other main surface.
And the unit cells 1 are alternately stacked, and the air flow grooves 3A have the same flow path width, and the depth of the grooves increases from the fuel gas outlet side to the fuel gas inlet side. A plurality of fuel gas flow grooves 6A,
This is characterized in that it has a plurality of fuel gas flow grooves having the same flow path width, and the depth of the grooves increases from the air outlet side to the air inlet side.

Also in this configuration, as in the second and third embodiments, sufficient hydrogen is also contained in the fuel gas downstream of the fuel gas flow groove 6A on the air inlet side, and The air downstream of the air flow groove 3A also contains sufficient oxygen. <Fifth Embodiment> FIG. 5 is a basic structural diagram of a single cell showing a fifth embodiment of the phosphoric acid fuel cell of the present invention.

The feature of this embodiment is that a single cell 1 having a basic structure similar to that of the first embodiment is provided with the same channel width,
A fuel electrode substrate 5 having a plurality of fuel gas flow grooves 6A whose groove depths increase from the air outlet side to the air inlet side.
The thickness of the air electrode base material 2b provided with the air passage 3 is made thinner toward the air inlet side and thicker toward the air outlet side. And
In addition, the point is that the sum of the thicknesses of the fuel electrode substrate 5b and the air electrode substrate 2b is the same in the plane.

In this structure, as in the first embodiment, the fuel gas downstream of the fuel gas flow groove 6A on the air inlet side contains sufficient hydrogen, so that there is no danger of corrosion.
Even when a plurality of fuel gas flow grooves 6A having different depths are provided, the remaining thickness of the fuel electrode base material 5b is substantially uniform, so that hydrogen in the fuel gas diffuses substantially uniformly. Since the fuel reaches the fuel electrode catalyst layer 5a, there is no possibility that the in-plane uniformity of the cell reaction is impaired. Also, the fuel electrode substrate 5b
And the sum of the thicknesses of the air electrode base material 2b and the air electrode base material 2b are the same in the plane, so that the thickness of the single cell 1 is also uniform in the plane.

<Sixth Embodiment> FIG. 6 is a basic structural view of a single cell showing a sixth embodiment of the phosphoric acid type fuel cell of the present invention. The feature of this embodiment is that a plurality of fuel cells having the same flow path width and having a deeper groove from the air outlet side to the air inlet side in a single cell 1 having a basic configuration similar to that of the third embodiment. The thickness of the reservoir plate 5e provided with the gas flow grooves 6A is formed to be thicker toward the air inlet side and thinner toward the air outlet side, and the thickness of the reservoir plate 2e provided with the air flow passage 3 is set closer to the air inlet side. Thinner, thicker on the air outlet side,
The point is that the sum of the thicknesses of the reservoir plate 5e and the reservoir plate 2e is formed to be the same in the plane.

In the present configuration, as in the third embodiment, the fuel gas downstream of the fuel gas flow groove 6A on the air inlet side contains sufficient hydrogen, so that not only there is no danger of corrosion, but also
Since the volume of power generated per unit length of the reservoir plate 5e becomes larger on the air inlet side where the amount of power generation is relatively large and the amount of phosphoric acid scattered is large, a relatively large amount of phosphoric acid can be held. Phosphoric acid can be supplied remarkably. Further, since the sum of the thicknesses of the reservoir plate 5e and the reservoir plate 2e is the same in the plane, the thickness of the unit cell 1 is also uniform in the plane.

<Seventh Embodiment> FIG. 7 is a basic structural view of a single cell showing a seventh embodiment of the phosphoric acid fuel cell of the present invention. The feature of this embodiment is that in the single cell 1 having the same basic configuration as the fifth embodiment, the air flow grooves 3B provided in the air electrode base material 2b have a shallow groove depth on the air inlet side, The point is that it is configured to have a deep flow groove on the air outlet side. Therefore, this configuration has the same features as the fifth embodiment, and the remaining thickness of the air electrode substrate 2b becomes uniform in the plane, so that oxygen in the air diffuses almost uniformly. As a result, the air reaches the air electrode catalyst layer 2a, and the in-plane uniformity of the battery reaction is maintained. Further, since the flow passage cross-sectional area of the air flow groove 3B increases on the downstream side and the flow velocity of the flowing air decreases, it becomes relatively easy to collect phosphoric acid scattered on the upstream side and mixed into the air. .

<Eighth Embodiment> FIG. 8 is a basic structural view of a single cell showing an eighth embodiment of the phosphoric acid type fuel cell of the present invention. The feature of the present embodiment is that in the single cell 1 having the basic configuration similar to that of the sixth embodiment, the air flow groove 3B provided in the reservoir plate 2e has a shallow groove depth on the air inlet side and an air outlet groove. The point is that it is configured to be a deep flow groove on the side. Therefore, in this configuration, the sixth
In addition to having the same features as the embodiment, the collection of phosphoric acid scattered on the upstream side and mixed in the air becomes relatively easy.

In the above-described fifth to eighth embodiments, the depth of the fuel gas passage groove 6A provided in the fuel electrode base material 5b or the reservoir plate 5e constituting the fuel electrode 2 is set to the depth. Is formed deeper as going from the air outlet side to the air inlet side.
It is easily understood that the same effect can be obtained even in a structure in which A is provided on the separate plate.

Further, the air flow grooves provided on the air electrode base material, the reservoir plate, or the separate plate constituting the air electrode are formed so that the width of the flow path is substantially the same, and the depth of the flow path is closer to the fuel gas inlet side. The flow groove is deeper and shallower on the fuel gas outlet side,
The constituent member having the air passage groove is formed thicker toward the fuel gas inlet side and thinner toward the fuel gas outlet side, and the constituent member provided with the fuel gas passage groove is further thinned toward the fuel gas inlet side. The same effect as in the above-described fifth to eighth embodiments can be obtained even if the two components are formed so that the sum of the thicknesses of the two components is substantially the same in the plane. Can be easily inferred without being shown in the figure, and the description thereof is omitted.

<Ninth Embodiment> FIG. 9 is a cross-sectional view showing the shape of a gas passage groove formed in a component of a single cell in a ninth embodiment of the phosphoric acid type fuel cell of the present invention. This figure is
Three types of representative examples of a plurality of gas flow grooves formed by changing the depth of the grooves uniformly in the constituent member 10 such as the electrode base material of the fuel electrode or the air electrode, the reservoir plate, or the separate plate. It was done. The feature of these gas flow grooves is that the cross-sectional shape of the groove end of the flow path has the same shape,
In addition, a plurality of gas flow grooves 11A (or 11B, 11B
C) is formed so that the deepest part is located on the same plane, that is, on the groove deepest part plane 12. (A) of the figure
Is a gas flow groove 11 in which the groove end of the flow path has a square cross section.
A, (b) is a gas flow groove 11 having a U-shaped cross section.
B, and (c) are gas flow grooves 11C having a U-shaped cross section with an open angle. In each case, the deepest portion of the gas flow groove is located on the groove deepest plane 12. doing.

FIG. 10 is a conceptual diagram showing a method of processing a gas flow groove in which the depth of the groove changes uniformly as shown in FIG. In this drawing, using a processing machine equipped with multiple rotary blades, a gas flow groove 11 in which a groove deepest plane 12 in which the deepest part of a square groove is located uniformly changes at an angle α is formed on a component 10. This shows a case where the work table 13 is inclined at an angle α with respect to a blade processing rotary shaft 15 of a groove processing blade 14 which rotates and performs groove processing, and a component member 10 for performing groove processing is incorporated thereon. After that, the gas flow grooves 11 are formed by processing the grooves by the groove processing blades 14 and moving the groove processing blades 14 in parallel along the blade processing rotation axis 15 to sequentially process the grooves. Therefore, by using this method, the gas flow grooves as shown in FIG. 9 can be processed very easily, and a single cell having such gas flow grooves can be manufactured with good workability.

[0035]

As described above, according to the present invention, (1) the phosphoric acid type fuel cell is configured as described in claim 1 or 2, so that the amount of hydrogen in the flowing fuel gas is Alternatively, the distribution of the amount of oxygen in the flowing air has been improved, and a phosphoric acid fuel cell that can be operated stably for a long period of time has been obtained.

(2) Further, if the fuel cell system is configured as described in claim 3 or 4, even if the fuel gas passages having different depths are formed in the constituent members, the fuel cell can be formed within the surface of the cell reaction. This is more preferable because the uniformity of the phosphoric acid is maintained, the phosphoric acid can be effectively replenished, or the scattered phosphoric acid is easily collected. (3) If the structure is further configured as described in claim 5, for example, by a manufacturing method as described in claim 6,
It can be manufactured very easily.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of a single cell showing a first embodiment of a phosphoric acid fuel cell of the present invention.

FIG. 2 is a basic configuration diagram of a single cell showing a second embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 3 is a basic configuration diagram of a single cell showing a third embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 4 is a basic configuration diagram of a single cell showing a fourth embodiment of the phosphoric acid fuel cell of the present invention.

FIG. 5 is a basic configuration diagram of a single cell showing a fifth embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 6 is a basic configuration diagram of a single cell showing a sixth embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 7 is a basic configuration diagram of a single cell showing a seventh embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 8 is a basic configuration diagram of a single cell showing an eighth embodiment of the phosphoric acid type fuel cell of the present invention.

FIG. 9 is a cross-sectional view showing the shape of a gas flow groove formed in a component of a single cell in a ninth embodiment of the phosphoric acid fuel cell of the present invention.

FIG. 10 is a conceptual diagram showing a method of processing a gas flow groove having a shape as shown in FIG. 9;

FIG. 11 is a basic configuration diagram of a single cell of a conventionally used phosphoric acid fuel cell.

[Explanation of symbols]

 Reference Signs List 1 single cell 2 air electrode 2a air electrode catalyst layer 2b air electrode substrate 2d air electrode substrate 2e reservoir plate 3 air flow groove 3A air flow groove 3B air flow groove 4 matrix 5 fuel electrode 5a fuel electrode catalyst layer 5b Fuel electrode base material 5c Reservoir plate 5d Fuel electrode base material 5e Reservoir plate 6 Fuel gas flow groove 6A Fuel gas flow groove 7 Separate plate 7A Separate plate 10 Component member 11 Gas flow groove 11A, 11B, 11C Gas flow groove 12 Groove deepest plane 13 Work table 14 Groove cutting tool 15 Tool cutting rotary axis

Claims (6)

[Claims] A fuel cell comprising a matrix containing phosphoric acid, a single cell in the form of a rectangular plate having a fuel electrode and an air electrode sandwiching the matrix, and a plurality of layers laminated with a gas-impermeable separator interposed therebetween. The fuel cell flows through a plurality of fuel gas passages provided in parallel in parallel with the fuel electrode or the separate plate so as to communicate with the side surface opposite to the fuel electrode or the separate plate. In the phosphoric acid fuel cell, in which air flows through a plurality of air passages provided in parallel with the fuel gas passages orthogonally to the opposite side surfaces and provided in parallel, and generating power by an electrochemical reaction, A plurality of fuel gas flow paths, the width of the flow path is substantially the same,
The depth of the flow path is deeper on the air inlet side, and the flow path is formed of a plurality of flow paths shallower on the air outlet side, or the plurality of air flow paths have substantially the same width, and A phosphoric acid-type fuel cell, wherein the flow path is deeper on the fuel gas inlet side and shallower on the fuel gas outlet side. 2. A fuel cell comprising a matrix containing phosphoric acid, a single cell in the form of a rectangular plate provided with a fuel electrode and an air electrode sandwiching the matrix, and a plurality of layers laminated with a gas-impermeable separator interposed therebetween. The fuel cell flows through a plurality of fuel gas passages provided in parallel in parallel with the fuel electrode or the separate plate so as to communicate with the side surface opposite to the fuel electrode or the separate plate. In the phosphoric acid fuel cell, in which air flows through a plurality of air passages provided in parallel with the fuel gas passages orthogonally to the opposite side surfaces and provided in parallel, and generating power by an electrochemical reaction, A plurality of fuel gas flow paths, the width of the flow path is substantially the same,
The flow path has a plurality of flow paths that are deeper toward the air inlet side and shallower toward the air outlet side, and the plurality of air flow paths have substantially the same width, and the depth of the flow path. A phosphoric acid-type fuel cell, wherein the flow path is deeper on the fuel gas inlet side and shallower on the fuel gas outlet side. 3. The phosphoric acid type fuel cell according to claim 1, wherein the plurality of fuel gas passages have substantially the same width, the depth of the passages increases toward the air inlet side, and the air outlet A structure comprising a plurality of flow passages shallower toward the side, wherein the constituent member provided with the fuel gas flow passage is formed of a member which is thicker toward the air inlet side and thinner toward the air outlet side, and includes an air flow passage. A phosphoric acid-type fuel, wherein the member is formed from a member that is thinner on the air inlet side and thicker on the air outlet side, and that the sum of the thicknesses of the two constituent members is substantially the same in the plane. battery. 4. The phosphoric acid fuel cell according to claim 1, wherein the plurality of air passages have substantially the same width, and the depth of the passages is greater toward the fuel gas inlet side. In the structure having a flow passage that is shallower on the outlet side, the constituent member provided with the air flow passage is formed of a member that is thicker on the fuel gas inlet side and thinner on the fuel gas outlet side, and has a fuel gas flow passage. The component member is formed of a member that is thinner on the fuel gas inlet side and thicker on the fuel gas outlet side, and is formed so that the sum of the thicknesses of the two component members is substantially the same in the plane. Acid type fuel cell. 5. The phosphoric acid fuel cell according to claim 1, wherein the fuel gas flow path or the air flow path comprising a plurality of flow paths having different depths, A phosphoric acid type fuel cell having a similar flow path cross-sectional shape, wherein the deepest portions of the plurality of flow paths are formed so as to be all located on the same plane. 6. The method for manufacturing a phosphoric acid fuel cell according to claim 5, wherein the fuel gas flow path or the air flow path comprising a plurality of flow paths having different depths is provided in a plurality. Using a processing machine equipped with a rotary blade, the angle between the center of the rotation axis of the rotary blade and the upper surface of the work table on which the workpiece is mounted is set to a predetermined value, and the rotary blade is processed by moving the blade in equilibrium. A method for producing a phosphoric acid fuel cell, comprising: