JP2002056863A - Electric energy generating element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric energy generating element capable of lowering the electrical contact resistance by improving the adhesiveness between a collector plate and an electrode without using a bolt, reducing the thickness of the whole of the structure and improving the output per unit area of the structure. SOLUTION: A fuel cell 1 is provided with a conductor membrane 2 for conducting hydrogen ions, a hydrogen electrode made of carbon and adhered closely to one surface of the conductor membrane at one surface thereof, a first collector plate 6 conductively connected to the other surface of the hydrogen electrode, an oxygen electrode 7 made of carbon and adhered closely to the other surface of the conductor membrane at one surface thereof, and a second collector plate 7 conductively connected to the other surface of the oxygen electrode. A first conductive adhesive layer 8 is interposed between the hydrogen electrode 3 and the first collector plate 6 and a second conductive adhesive layer 9 is interposed between the oxygen electrode 4 and the second collector plate 7 to lower the contact resistance between the electrodes and the collector plates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric energy generating device, and more particularly to a hydrogen electrode, an oxygen electrode, a conductor film interposed between the hydrogen electrode and the oxygen electrode, the outside of the hydrogen electrode and the outside of the oxygen electrode. The present invention relates to a fuel cell including a pair of current collectors arranged in a fuel cell.

[0002]

2. Description of the Related Art As an electric energy generating element, FIG.
There is a so-called fuel cell which generates electricity by reacting hydrogen and oxygen as shown in FIG. Here, the fuel cell 101
Denotes a conductor film 102 and a hydrogen electrode 1 sandwiching the conductor film 102
Power generation cell 105 composed of oxygen and oxygen electrode 104
And a hydrogen electrode current collector 106 and an oxygen electrode current collector 107 sandwiching the power generation cell 105.

[0003] The conductor film 102 is a polymer film that conducts only hydrogen ions. The hydrogen electrode 103 is a carbon electrode with a catalyst, and one surface thereof is in close contact with one surface of the conductor film 102. The hydrogen electrode current collector 106 is a conductor and is conductively connected to the other surface of the hydrogen electrode 103. In order to supply hydrogen gas to the hydrogen electrode 103,
The hydrogen electrode current collector 106 has a plurality of through holes 106a. In order to prevent leakage of the supplied hydrogen gas, a seal member 110 is arranged around the hydrogen electrode 103. The oxygen electrode 104 is also a carbon electrode with a catalyst, and one surface thereof is in close contact with the other surface of the conductor film 102. The oxygen electrode current collector 107 is a conductor and is conductively connected to the other surface of the oxygen electrode. In order to supply air (oxygen) to the oxygen electrode 104,
The oxygen electrode current collector 107 also has a plurality of through holes 107a.

The current collectors 106 and 107 are provided for efficiently and easily taking out the electric power generated in the power generation cell 105, and are provided in close contact with the opposed hydrogen electrode 103 and oxygen electrode 104, respectively. Sex is required. For this purpose, the current collectors 106 and 107 are connected to these electrodes 103 and 1.
04 and the outer dimensions of the conductor film 102,
Insulating bolts 108 are fastened between current collectors that do not overlap the electrodes and the like. An insulating spacer 109 is interposed between the current collectors 106 and 107 outside the power generation cell 105, and an insulating bolt 108 penetrates through the insulating spacer.

[0005]

However, in the configuration of the conventional fuel cell 101 shown in FIGS.
6, 107 and the carbon electrodes 103, 104 have a large electrical contact resistance, and the current collecting effects of the current collectors 106, 107 cannot be sufficiently exhibited. Further, since the insulating bolts 108 are arranged outside the outer contour of the power generation cell 105, the dimensions of the entire structure are increased by that amount, and the output per unit area of the structure is reduced. Further, as described above, the power generation cell 1
Since the current collectors 106 and 107 are fastened by bolts 108 outside the electrode 05, contact with the current collectors 106 and 107 around the electrodes 103 and 104 can be maintained to some extent. In the center of the current collector 106, 1
When 07 is thin, the current collector bends and the electrodes 103 and 104 are bent.
And the current collection effect is reduced. In order to prevent this, it is necessary to increase the rigidity of the current collectors 106 and 107. However, the thickness of the current collector increases, and the size of the structure as a whole increases. Further, when bolts are also inserted through the center of the electrodes 103 and 104 in order to improve the contact at the center of the electrodes 103 and 104, the power generation effective area of the electrodes and the conductor film is reduced by the sectional integral of the bolt. I do.

Therefore, the present invention can reduce the electrical contact resistance by improving the adhesion between the current collector and the electrode without using bolts, and can reduce the thickness of the entire structure. It is an object of the present invention to provide an electric energy generating element capable of improving the output per unit area of a structure.

[0007]

In order to achieve the above object, the present invention provides a conductor film for conducting hydrogen ions, a hydrogen electrode disposed on one side of the conductor film, and a hydrogen electrode. A first current collector disposed on the opposite side of the conductor film and electrically connected to the hydrogen electrode; and an oxygen electrode disposed on the opposite side of the conductor film from the hydrogen electrode. An electrical energy generating element comprising a second current collector disposed on the oxygen electrode on a side opposite to the conductor film and electrically connected to the oxygen electrode, wherein the hydrogen electrode and the first A first conductive adhesive layer is interposed between the hydrogen collector and the first current collector to physically contact the hydrogen electrode and the first current collector while improving conductivity, and A second conductive adhesive layer is interposed between the electrode and the second current collector to physically connect the oxygen electrode and the second current collector. Provides electrical energy generating device is made to improve the conductivity causes dressed.

[0008]

1 and 2 show an embodiment in which the electric energy generating element of the present invention is applied to a fuel cell.
It will be described based on. Fuel cell 1 according to first embodiment
A power generation cell 5 comprising a conductor film 2, a hydrogen electrode 3 and an oxygen electrode 4 sandwiching the conductor film 2, a hydrogen electrode current collector 6 and an oxygen electrode current collector 7 sandwiching the power generation cell 5, 1 and a second conductive adhesive layer 8, 9.

The conductor film 2 is a polymer film that conducts only hydrogen ions. The hydrogen electrode 3 is a carbon electrode with a catalyst, and one surface thereof is in close contact with one surface of the conductor film 2. The hydrogen electrode current collector 6 is a conductor and is conductively connected to the other surface of the hydrogen electrode 3 via a first conductive adhesive layer 8. In order to supply hydrogen gas to the hydrogen electrode 3, a plurality of hydrogen through holes 6 a, 8 a are formed coaxially in the hydrogen electrode current collector 6 and the first conductive adhesive layer 8.
In order to prevent leakage of the supplied hydrogen gas, a sealing material 10 is arranged around the hydrogen electrode 3. The oxygen electrode 4 is also a carbon electrode with a catalyst, and one surface thereof is in close contact with the other surface of the conductor film 2. The oxygen electrode current collector 7 is a conductor and has a second surface on the other surface of the oxygen electrode 4.
The conductive adhesive layer 9 is electrically connected to the oxygen electrode current collector 7 and the second conductive adhesive layer 9 in order to supply air (oxygen) to the oxygen electrode 4. Through-hole 7a,
9a is formed coaxially.

The current collectors 6 and 7 are for efficiently and easily extracting power generated in the power generation cell, and are made of a gold-plated nickel material. The first and second conductive adhesive layers 8 and 9 are, for example, dodent (trade name, manufactured by Nihon Handa Co., Ltd.), and have an electric resistance of 1.7 × 10 ⁻⁴ Ωcm. As the conductive adhesive, various curable polymers such as epoxy-based, acrylic-based, and urethane-based materials containing metal particles such as silver can be used, but alloy-based adhesives such as gold-silicon can be used. It is also possible to use. A screen is coated with a conductive adhesive on one surface of the current collectors 6 and 7 where the through holes 6a and 7a are formed, and then pressure-bonded to the electrodes 3 and 4 so as to be coaxial with the through holes 6a and 7a. Through holes 8a, 9a
Can be formed.

In the above configuration, when hydrogen gas is supplied from the through hole 6a of the hydrogen electrode current collector 6, the hydrogen gas passes through the through hole 8a of the first conductive 3 is supplied. The hydrogen gas is converted into hydrogen ions by the hydrogen electrode 3, and the hydrogen ions pass through the conductor film 2 and move to the oxygen electrode 4 side. Note that the hydrogen supplied to the hydrogen electrode 3 is prevented from leaking to the outside by the sealing material 10. At the same time, air (oxygen) is supplied to the through-hole 7 a of the oxygen electrode current collector 7.
Is supplied to the oxygen electrode 4 through the through holes 9 a of the second conductive adhesive layer 9. Then, hydrogen ions and oxygen react at the oxygen electrode 4 to generate water. At this time, hydrogen emits electrons to the hydrogen electrode 3 to generate a potential difference, which is extracted from the current collectors 6 and 7 via the conductive adhesive layers 8 and 9.

The hydrogen electrode 3 and the oxygen electrode 4 are made of carbon, have high resistance per se, and have carbon particles in a discontinuous state on the surface. Therefore, the electrical contact resistance value through the first conductive adhesive layer 8 is higher than the electrical contact resistance when the current collector 6 and the hydrogen electrode 3 and the current collector 7 and the oxygen electrode 4 are in direct contact. The electrical contact resistance between the current collector 6 and the hydrogen electrode 3 and the electrical contact resistance between the current collector 7 and the oxygen electrode 4 via the second conductive adhesive layer 9 Therefore, the current collecting effect of the current collectors 8 and 9 can be enhanced.

The electric energy generating element according to the present invention comprises:
The present invention is not limited to the embodiments described above, and various modifications are possible within the scope described in the claims. For example, when the conductive adhesive layer is formed of a material having good air permeability, it is not necessary to form the through holes 8a and 9a as in the above-described embodiment. In the above-described embodiment, the conductive adhesive is applied to the entire surface of the current collector by, for example, screening. However, a plurality of conductive adhesives are scattered on the current collector, and a predetermined area is applied when the electrode is pressed. It may be formed so as to spread out.

The fuel cell can be operated in a non-humidified state by employing a structure in which the carbon-made hydrogen electrode is impregnated with a fullerene derivative-based proton conductor and the oxygen electrode is impregnated with an organic-based proton conductor. Even if you do
Hydrogen ion conduction in the electrode is performed well. Further, in the oxygen electrode, water is generated by the reaction between hydrogen ions and oxygen ions, so that the oxygen electrode can be humidified with the water. Further, by adopting a structure in which the conductor membrane is impregnated with a fullerene derivative-based proton conductor, hydrogen ion conduction can be performed in the conductor membrane even in a non-humidified state.

Further, the conductor film and the hydrogen electrode, and the conductor film and the oxygen electrode may not only completely adhere to each other but may have a slight gap between them.

[0016]

According to the electric energy generating device of the first aspect, the first and the second current collectors are provided between the first current collector and the hydrogen electrode and the second current collector and the oxygen electrode respectively. Since the second conductive adhesive layer is interposed, the contact resistance between the electrode and the current collector can be kept low, and high current collection efficiency can be obtained.

Further, not only are no bolts necessary around the cells for fastening between the current collectors, but also bolts penetrating the cells are not required, so that an area for fastening the bolts is not required, and the electric energy generating element is not required. In terms of the overall configuration, the area ratio of cells per structure area can be increased.
Furthermore, since no bolt is required, the current collector itself does not need to be provided with high rigidity, and the current collector can be made thinner. Therefore, the thickness of the entire structure can be reduced, resulting in a compact device. . In addition, since it is not necessary to fasten bolts around the cell, there is no inconvenience such as a decrease in adhesion to the current collector at the center of the cell.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a fuel cell according to a first embodiment of the present invention.

FIG. 2 is a plan view of the fuel cell of FIG. 1 viewed from the oxygen electrode current collector side.

FIG. 3 is a sectional view of a conventional fuel cell.

FIG. 4 is a plan view of the fuel cell of FIG. 3 viewed from the oxygen electrode current collector side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel cell which is an electric energy generation element 2 Conductor film 3 Hydrogen electrode 4 Oxygen electrode 5 Cell 6 Hydrogen electrode current collector 7 Oxygen electrode current collector 8 First conductive adhesive layer 9 Second conductive adhesive layer

Claims (1)

[Claims] A conductive film for conducting hydrogen ions; a hydrogen electrode disposed on one side of the conductive film; and a hydrogen electrode disposed on a side of the hydrogen electrode opposite to the conductive film. A first current collector electrically connected to the first electrode; an oxygen electrode disposed on the opposite side of the conductor film from the hydrogen electrode; and a first current collector disposed on the opposite side of the oxygen electrode to the conductor film. An electrical energy generating element comprising: a second current collector electrically connected to the oxygen electrode; wherein a first conductive adhesive is provided between the hydrogen electrode and the first current collector. An agent layer intervenes to physically contact the hydrogen electrode and the first current collector and improve conductivity, and between the oxygen electrode and the second current collector, The second conductive adhesive layer intervenes to physically contact the oxygen electrode and the second current collector while improving the conductivity. Electrical energy generating element.