JP2002280049A - Integrated type fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an integrated type fuel cell capable of increasing voltage to be generated on one layer cell. SOLUTION: This integrated type fuel cell is constituted by forming a large number of divided electrolytic units 12 to be electrolytic parts by processing a substrate and a frame type insulating part 13 to insulate the units from each other, providing an electrode film 14 with a cathode pole side catalyser and an electrode film 15 with an anode pole side catalyser on both surfaces of each of the divided electrolytic units 12, forming divided unit cells 18 by sandwiching thm with a separator 16 for a cathode pole and a separator 17 for an anode pole and alternately connecting positive electrodes and negative electrodes of these divided unit cells 18 in series.

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 an integrated fuel cell which can be highly integrated and can obtain a high voltage from a low voltage. .

[0002]

2. Description of the Related Art A polymer electrolyte fuel cell using hydrogen gas as fuel and oxygen gas as oxidant has a cell structure as shown in FIG.

In a fuel cell 100 shown in FIG. 7, a negative electrode (hydrogen electrode) 102 and a positive electrode (oxygen electrode) 103 provided with a catalyst are provided on both sides of a polymer electrolyte membrane 101, and are further sandwiched therebetween. , Separators 104 and 105 are provided.

The separators 104 and 105 are respectively
Hydrogen supply passage (groove) 106 and oxygen supply passage (groove)
107.

[0005] Hydrogen gas and oxygen gas are respectively guided from outside to the passages 106 and 107 via supply holes (not shown) and supplied to the negative electrode 102 and the positive electrode 103, respectively.

In the negative electrode (hydrogen electrode) 102 to which the catalyst has been applied, the hydrogen supply passage (groove) 1 of the separator 104 on the negative electrode side is formed.
The hydrogen gas supplied from 06 passes through the anode 7 (hydrogen electrode 7 provided with a catalyst) 102 and reaches near the reaction zone, where it is absorbed by the catalyst and split into active hydrogen ions and electrons. The hydrogen ions, together with the water in the electrolyte 100,
Positive electrode (oxygen electrode) 10 which has moved through 00 and has been provided with a catalyst
Go to 3.

On the other hand, a positive electrode (oxygen electrode) 1 provided with a catalyst
In 03, in the presence of the catalyst, two electrons are received from the positive electrode (oxygen electrode) 103 provided with the catalyst, and oxygen molecules supplied from the oxygen supply passage (groove) 107 of the separator 105 on the positive electrode side are It reacts with water from the polymer electrolyte membrane 101 to generate hydroxyl ions.

[0008] _1/2 O ₂ + H ₂ O → 2OH ^- The hydroxyl ions generated at the positive electrode (oxygen electrode) 103 react with the hydrogen ions moving through the polymer electrolyte membrane 101 to generate water, Configure the entire circuit.

Therefore, the reaction of the whole battery is H ₂ + 1 / 2O ₂ → 2H ₂ O, and the oxygen in the hydrogen-coated air in the fuel gas reacts to generate water.

[0010] The theoretical voltage due to this reaction is 1.23 V, but there are actually various losses, and the generated voltage is
At present, it is about 0.7 V at best. That is, the generated voltage of the single-layer unit between the separators 104 and 105 is 0.1.
7 V, and this type of fuel cell is generally used as a fuel cell stack by stacking a predetermined number.

[0011]

As described above, in the case of the conventional stack-type solid polymer fuel cell, the generated voltage per cell is as low as about 0.7 V, and in order to increase the voltage, a multilayer structure is used. Need to be able to stack,
The merit of this structure is pressure division. However, it is necessary to incorporate a separator and a cooling plate in a large space, and the structure itself is wasteful, and at the same time, the shape becomes close to a cube, resulting in a bulky shape.

Further, the relationship between the generated voltage and the current has a problem that it is suitable for a low voltage and a large current, but is not suitable for a small current and a high voltage. Further, it is not suitable for semiconductors having a small amount of power, and is not suitable for power sources of cars, home power supplies, and mobile phones.

That is, the disadvantage of the conventional cell structure is that, although the voltage generated in the unit cell and the amount of power per unit area are constant, the one-layer unit cell is large.
This is a point that results in a bulky structure.

An object of the present invention is to solve the above-mentioned problems and to provide an integrated fuel cell which can increase the voltage generated in a single-layer cell.

[0015]

In order to achieve the above object, according to the first aspect of the present invention, a single-layer polymer electrolyte fuel cell is divided into a large number of planes to form divided unit cells. This is an integrated fuel cell in which the positive and negative electrodes of the divided unit cells are alternately connected in series.

According to a second aspect of the present invention, an insulating substrate is processed to form a divided electrolyte unit serving as a large number of electrolyte portions and a frame-shaped insulating portion for insulating the units from each other. In addition, an electrode film with a catalyst on the cathode side and an electrode film with a catalyst on the anode side are provided, and further divided between the cathode electrode separator and the anode electrode separator to form a divided unit cell. , Are integrated type fuel cells alternately connected in series.

According to a third aspect of the present invention, an insulating substrate is processed to form a divided electrolyte unit serving as a large number of electrolyte portions and a frame-shaped insulating portion for insulating the units from each other. A cathode electrode side catalyst-equipped electrode film and an anode electrode side catalyst-equipped electrode film, further sandwiched between a cathode electrode separator and an anode electrode separator to form a divided unit cell, and the cathode electrodes of adjacent divided unit cells This is an integrated fuel cell in which the electrode film with the catalyst on the side and the electrode film with the catalyst on the anode electrode side 35 are shifted from each other, and the divided electrode cells are connected in series by electrically connecting the electrode films overlapping one above the other. .

According to a fourth aspect of the present invention, there is provided an integrated fuel cell in which the integrated fuel cells of the second aspect are stacked in multiple layers, and the upper and lower integrated fuel cells are connected in series.

According to a fifth aspect of the present invention, there is provided an integrated fuel cell in which the integrated fuel cells of the third aspect are stacked in multiple layers, and the upper and lower integrated fuel cells are connected in series.

According to a sixth aspect of the present invention, an insulating substrate is processed to form a divided electrolyte unit serving as a large number of electrolyte portions, and a frame-shaped insulating portion for insulating the units from each other. The cathode electrode side catalyst-equipped electrode film and the anode electrode side catalyst-equipped electrode film are provided to form a membrane electrode assembly. On the other hand, the anode electrode side of the membrane electrode assembly is The electrode film with a catalyst is in contact with the electrode film with a catalyst, and the electrode film with a catalyst on the cathode electrode side is
This is an integrated fuel cell in which a membrane electrode assembly is adhered so as to open to the cathode channel side, and divided unit cells of these membrane electrode assemblies are connected in series.

According to a seventh aspect of the present invention, a large number of the integrated fuel cells of the sixth aspect are arranged so as to face the cathode flow path, and an anode gas is passed through the anode separator of each of the integrated fuel cells. This is an integrated fuel cell in which each integrated fuel cell is connected in series.

In the above, a single-layer fuel cell unit itself is integrated by processing an insulating substrate to form a divided electrolyte unit serving as a large number of electrolyte portions and a frame-shaped insulating portion for insulating the units. By constructing the divided unit cells and connecting the positive electrode and the negative electrode alternately in series, it becomes possible to provide a single-layer fuel cell having a high generated voltage.

This integrated type fuel cell can be laminated and can be a fuel cell having a higher generated voltage.

Further, by forming an integrated structure in the layer, a structure having various degrees of freedom can be obtained, and a high voltage can be taken for a current, thereby producing a highly efficient fuel cell. And the number of parts can be reduced, and the manufacturing cost can be greatly reduced.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1B is a plan view of the integrated fuel cell of the present invention viewed from the cathode side, FIG. 1A is a sectional view taken along the line AA of FIG. 1B, and FIG. c) shows a sectional view taken along the line BB.

First, as shown in FIG. 1A, an insulating substrate is processed to form a vertically striped or strip-shaped divided electrolyte unit 12 and a frame-shaped insulating portion 13 around the divided electrolyte unit 12. did.

Here, a 50 μm thick fluororesin film was used as the insulating substrate. Since the fluororesin film itself has an insulating property and is treated with a sulfonic acid group to become an ion exchanger, a portion of the fluororesin film excluding the frame-shaped insulating portion 13 is subjected to a sulfonic acid group treatment. A number of split electrolyte units 12 can be formed.

Above and below each divided electrolyte unit 12,
Electrode film 1 with catalyst on cathode side made of carbon paper
4. An anode-side catalyst-coated electrode film 15 made of carbon paper is attached to each, and further sandwiched from above and below by a cathode separator 16 and an anode separator 17 formed of graphite sintered body or the like to form a divided unit cell. 18
To form

The adjacent separators 16, 16, and 17,
The separators 16 and 17 are insulated from each other with an insulating seal layer 19 interposed therebetween, and the outer peripheral portion is further sealed with a peripheral insulating seal layer 20.

An oxygen supply passage (groove) 21 through which oxygen or air flows is formed in each of the cathode electrode separators 16 on the upper surface, and a hydrogen supply passage (groove) through which hydrogen flows through the anode separator 17 on the lower surface. ) 22 are formed, and oxygen and hydrogen are supplied to the corresponding divided unit cells 18 from the upper and lower separators 16 and 17. In this case, oxygen and hydrogen pass through the divided electrolyte unit 12, but the frame-shaped insulating portions 13 between the adjacent divided electrolyte units 12 both serve as gas separation layers for oxygen and hydrogen.

When these four divided unit cells 18 are formed, for example, as shown in the figure, the left unit cell 18-1 to the right cell 18-4 are electrically connected in series. That is, the anode of the cell 18-1 and the cathode of the cell 18-2, the anode of the cell 18-2 and the cathode of the cell 18-3, the anode of the cell 18-3 and the cathode of the cell 18-4. By arranging the cathode electrodes next to each other, it is possible to form the integrated fuel cell single-layer cell 28 in a substantially stacked state.

FIGS. 1B and 1C show the case where the leads 23,
24 and the upper and lower penetrating conductive parts 25 each cell 18-1 to 18-4
Are connected in series. First, the cathode separator 16 on the upper surface is provided with a cathode lead 23 connected to the cathode electrode for each cell 18, and the anode separator 17 on the lower surface is provided on the cathode separator 16. An anode-side lead 24 connected to the anode of each cell 18 is provided. These leads 23 and 24 overlap vertically between adjacent cells 18, and the upper and lower penetrating conductive portions 25 electrically connect the leads 23 and 24 to each other. By connecting, each cell 18 becomes an integrated type fuel cell single-layer cell 28 connected in series.

The voltage generated in each of the cells 18 is 0.7 V. An electromotive force of 2.8 V can be obtained by connecting four cells in series.

FIG. 2 shows another embodiment of the present invention.
An example in which a 4 × 3 cell 38 is manufactured is shown.

First, as shown in FIG. 2A, a frame-shaped insulating portion 33 is formed in an insulating base 31, and an island-shaped 4 × 3 divided electrolyte unit 32 is formed on the frame-shaped insulating portion 33. Placed.

An electrode film 34 with a catalyst on the cathode electrode side and an electrode film 35 with a catalyst on the anode electrode side are attached to each of the divided electrolyte units 32, and further sandwiched between the cathode electrode separator 36 and the anode electrode separator 37 from above and below. Then, a divided unit cell 38 is formed. When forming the divided unit cells 38, as shown in FIG. 2 (a), the cathode-side catalyst electrode film 34 and the anode-side catalyst electrode film 35 are staggered and adhered to each other. Unit cell 3 adjacent to electrode film 34
The electrode film 35 with a catalyst on the anode side on the lower side of 8 is overlapped via the frame-shaped insulating portion 33, and the electrode films 34, 35 are electrically connected by the upper and lower penetrating conductive portions 45. An integrated fuel cell single-layer cell 48 is formed.

FIG. 2 (b) shows the outline of the displacement of the electrode film 34 with the catalyst on the cathode side and the electrode film 35 with the catalyst on the anode side in the 4.times.3 divided electrolyte unit 32. Each cell 38 is connected in series in a self-shape as seen in the figure to form an integrated fuel cell single-layer cell 48.

In this case, the cathode-side electrode film with catalyst 3
4. In order to improve the electrical connection with the upper and lower penetrating conductive portions 45, a composite of carbon paper and carbon felt having good conductivity is used for the electrode film 35 with catalyst on the side of the carbo-anode electrode. At this time, minute holes for penetration are made in the frame-shaped insulating portion 33 and the separators 36 and 37, conduction is established by gold plating, and then connection is made by filling the through holes with resin or the like. The separators 36 and 37 may be formed of a sintered body of graphite as described with reference to FIG. 1. However, since it is necessary to insulate the adjacent separators 36, 36 and 37 and 37, for example, injection of polycarbonate is performed. Since the separators 36 and 37 can be formed as an integral product without the need for insulation, the structure can be simplified by using an insulator made of a molded product.

Oxygen or air is passed through the oxygen supply passage (groove) 41 of the cathode separator 36 on the upper surface, and the hydrogen supply passage (groove) 4 of the anode separator 37 below.
Flow hydrogen through 2. In the figure, an inflow groove from outside is not shown, but it is configured to flow into these passages 41 and 42.

This one-layer cell 48 of the integrated type fuel cell comprises:
Stacking of 4 × 3 = 12 divided unit cells 38 in one layer is possible, and an electromotive force of 0.7 × 12 = 8.4 V can be generated.

FIG. 3 shows an example in which four layers of the integrated fuel cell single-layer cell 28 described in FIG. 1 are laminated via an insulating layer 59 to form a fuel cell. In this case, by alternately electrically connecting the upper and lower ends of the integrated type fuel cell single-layer cells 28 with the interlayer short-circuit leads 55, 0.7 ×
An electromotive force of 4 × 4 = 11.2 V can be obtained.

FIG. 4 shows an example in which a fuel cell is constructed by stacking three layers of the single-layer cell 48 of the integrated type fuel cell described in FIG. In this case, by connecting the last unit and the first unit unit cells 38 of the upper and lower integrated type fuel cell single-layer cells 48 sequentially in series with the interlayer short-circuit lead 56, 0.7 × 3 × 4 × An electromotive force of 3 = 25.5V is obtained.

FIG. 5 shows still another embodiment of the present invention.

FIG. 5 shows an example in which a three-integrated cell is manufactured. First, as shown in FIG. 5 (a), an insulating substrate is processed to form a divided electrolyte unit which becomes a large number of electrolyte portions. 72, and a frame-shaped insulating portion 73 for insulating the units 72 from each other. An electrode film 74 with a catalyst on the cathode side and an electrode film 75 with a catalyst on the anode side are provided on both surfaces of each divided electrolyte unit 72. The joined body 80 is formed.

On the other hand, as shown in FIG. 5 (c), a substantially cylindrical anode electrode separator 77 is formed by bending the hydrogen supply passage (groove) 82 so as to be on the outside, and the anode electrode separator 77 is formed. As shown in FIG. 5 (a), 77 is connected via an insulating layer 79, and guide insulating plates 90 are provided at both ends so that the anode-side catalytic electrode film 75 contacts between the guide insulating plates 90. Then, the membrane electrode assembly 80 is attached to the anode electrode separator 77 to form the divided unit cells 78, and the membrane electrode assembly 80
The lower end of the anode electrode separator 77 is closed with a terminal seal cover 84 made of Kapton, and the cells 78 are connected in series to form a cylindrical integrated fuel cell single-layer cell 88.

The connection of each divided unit cell 78 is performed by connecting the separator 77 for the anode where the terminal seal cover 84 is located.
On one side, a cathode-side lead 83 connected to the cathode-side electrode film with catalyst 74 is formed, and on the other side, an anode-side lead 84 connected to the electrode film with anode electrode 75 with catalyst.
And the adjacent leads 83 and 84 are made to overlap, and the leads 83 and 84 are electrically connected by the through conductive portion 85 to connect the cells 78 in series.

The cylindrical integrated fuel cell single-layer cell 8
Reference numeral 8 denotes a structure in which hydrogen gas flows into the cylindrical anode electrode separator 77, and the cathode side is open to the cathode channel 81.

In this case, oxygen flows about 20% in the cathode flow path 81, so that the contact area is smaller than that of the anode side. The entire surface is open, and the substantially contacting area is larger than the area in which the anode-side catalyst electrode film 75 contacts the hydrogen supply passage (groove) 82, so that the power generation efficiency is increased and the generated water is discharged smoothly. Can be done.

The cylindrical integrated fuel cell single-layer cell 8
As for the generated electromotive force of No. 8, 0.7 × 3 = 2.1 is obtained.

FIG. 6 shows an example in which a cylinder type fuel cell is constructed using the integrated type fuel cell single-layer cell 88 of FIG.

In this case, the integrated fuel cell single-layer cell 8
The electromotive force of 0.7 × 3 × 4 = 8.4 V was obtained by connecting each of the integrated type fuel cell single-layer cells 88 in series with the interlayer short-circuit lead 93 while facing the cathode channel 8 to the cathode flow channel 81. .

Although the present embodiment has been described above, various modifications are possible in the present invention. For example, as a polymer electrolyte membrane, a 50 μm-thick fluororesin film was used for a substrate, which itself was insulative, and was treated with a sulfonic acid group to form an ion exchanger, which was described as a polymer electrolyte membrane. However, it is not limited to this material,
Any material may be used as long as the electrolyte portion can be formed integrally with the insulating portion.

As the polymer membrane, Nafion, Gore, Flemion,
Aciplex and the like are known, but before adding a sulfone group, they are insulating materials, and any of them can be used. The present invention resides in that a polymer electrolyte portion and an insulating portion having a specific arrangement are formed in an electrolyte membrane, and a number of partial battery cells are formed in a single-layer film, and the material is not specified. The thickness is also described as 50 μm, but as long as it functions as a fuel gas separator, the thinner is preferable, and the characteristics are improved.

As the material of the separator, graphite, copper, and polycarbonate are used. If the material is conductive, it depends on whether it is a cathode electrode or an anode electrode, but a metal material for corrosion resistance can also be used. A material such as applying a conductive anticorrosive can also be used. In addition, any insulating material may be used, such as ceramic or a material having an insulating surface.

Regarding the electrode film with catalyst, in this embodiment, the carbon paper with catalyst (Pt on the surface in contact with the electrolyte membrane) is used.
It is explained by using an example in which a catalyst is applied), or a composite formed of carbon felt having good conductivity is used. However, in order to further improve conductivity, it is also possible to use a porous or net-like corrosion-resistant metal. good.

In the embodiment of the present invention, the example in which the number of accumulations per layer is 3 to 12 has been described. However, it is naturally possible to increase the number of accumulations, and it is also possible to increase the number of accumulations to 100 to 200. The invention is advantageous in that it can support a wide range of design conditions.

By forming an integrated fuel cell in one layer, a flat structure and a high voltage can be obtained. Depending on the installation space, if you want to use a household power supply, type it into the wall, if it is for cars, under the seat,
It can be applied to the type that is stored under the body. It can also be used for semiconductor devices, notebook computers, mobile phones, etc.

An integrated type microcurrent voltage battery is obtained, and as a result, a high voltage battery can be obtained although the generated current is small.

When the separator is cylindrical, the fuel cell has a cooling function. The inside of the cylinder is hydrogen and the outside is air,
The chiller structure of the heat exchanger can be used, the effect of cooling the heat generation can be expected, and the fuel cell structure having a cooling function can be obtained.

[0061]

In summary, according to the present invention, the following effects can be obtained.

(1) A high-voltage fuel cell structure that can be used in a variety of ways in terms of voltage use, shape, and configuration can be used, and the condition can be applied to a high degree.

(2) In the case of a cylindrical type, a battery cell structure having a cooling function can be provided, and a structure capable of discharging generated water which is a problem in a fuel cell can be provided.

(3) Since the cells can be integrated, the phenomenon of the number of parts and an integrated manufacturing method can be adopted, so that the cost can be reduced and the reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing another embodiment of the present invention.

FIG. 3 is a view showing a form of a fuel cell in which the integrated type fuel cells of FIG. 1 are stacked in multiple stages.

FIG. 4 is a diagram showing a form of a fuel cell in which the integrated type fuel cells of FIG. 2 are stacked in multiple stages.

FIG. 5 is a diagram showing another embodiment of the present invention.

6 is a view showing a form of a fuel cell in which a large number of cylindrical integrated fuel cells of FIG. 5 are arranged.

FIG. 7 is a perspective view showing a conventional fuel cell unit.

[Explanation of symbols]

 12 Split Electrolyte Unit 14 Cathode Electrode with Catalyst 15 Electrode with Cathode 16 Cathode Separator 17 Anode Separator 18 Split Unit Cell

Claims (7)

[Claims] 1. A solid polymer fuel cell of one layer is divided on a large number of planes to form divided unit cells, and the positive and negative electrodes of the divided unit cells are connected alternately in series. Integrated fuel cell. 2. An insulative substrate is processed to form a divided electrolyte unit serving as a large number of electrolyte portions and a frame-shaped insulating portion for insulating the units, and a cathode electrode side is provided on both surfaces of each divided electrolyte unit. Providing an electrode film with a catalyst and an electrode film with a catalyst on the anode electrode side, and further sandwiching the separator for the cathode electrode and the separator for the anode electrode to form divided unit cells, the positive electrode and the negative electrode of these divided unit cells are
An integrated fuel cell unit, which is connected alternately in series. 3. An insulative substrate is processed to form a plurality of divided electrolyte units serving as electrolyte portions and a frame-shaped insulating portion for insulating the units, and a cathode electrode side is provided on both sides of each divided electrolyte unit. An electrode membrane with a catalyst and an electrode membrane with a catalyst on the anode side are provided, and further sandwiched between a separator for the cathode electrode and a separator for the anode to form a divided unit cell. And an electrode membrane provided with a catalyst on the anode side shifted from each other, and electrically connected electrode membranes which are overlapped on the upper and lower sides thereof, and the divided unit cells are connected in series. 4. An integrated fuel cell according to claim 2, wherein the integrated fuel cells according to claim 2 are stacked in multiple layers, and the upper and lower integrated fuel cells are connected in series. 5. An integrated fuel cell according to claim 3, wherein the integrated fuel cells according to claim 3 are stacked in multiple layers, and the upper and lower integrated fuel cells are connected in series. 6. An insulative substrate is processed to form a divided electrolyte unit serving as a large number of electrolyte portions and a frame-shaped insulating portion for insulating the units from each other. A catalyst electrode membrane and an anode electrode catalyst membrane are provided to form a membrane electrode assembly,
The membrane electrode assembly such that the anode-side catalyst electrode film of the membrane electrode assembly contacts the substantially cylindrical anode electrode separator, and the cathode-side catalyst electrode film opens to the cathode channel side. Characterized in that the divided unit cells of the membrane electrode assembly are connected in series. 7. An integrated fuel cell according to claim 6, wherein a plurality of the integrated fuel cells are arranged so as to face the cathode flow path, and an anode gas flows through the anode electrode separator of each of the integrated fuel cells. An integrated fuel cell comprising cells connected in series.