JP4611080B2 - Fuel cell - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a fuel cell, and in particular, a fuel characterized by a structure for realizing a small and high-power fuel cell at a low cost by using carbon nanotubes as an electrode and a fuel / gas flow path to increase the degree of integration. It relates to batteries.

In recent years, fuel cells have been attracting attention as an energy source that is clean and has high energy conversion efficiency due to increasing awareness of environmental issues and energy conservation. In such fuel cells, fuel such as H ₂ or methanol is used. Direct electromotive force is generated by reacting with air (O ₂ ).

As a representative prior art, a counter electrode type fuel cell and a planar type fuel cell are known. Here, these fuel cells will be described with reference to FIG. 25 and FIG.
See FIG.
FIG. 25 is a conceptual configuration diagram of a conventional counter electrode type fuel cell, which has a structure in which a pair of electrodes and a fuel flow path are arranged on both sides with a polymer electrolyte membrane 81 interposed therebetween.

In the figure, the left side is the hydrogen fuel side, and the hydrogen fuel flow path 83 is in contact with the polymer electrolyte membrane 81 via the fuel electrode 82 made of porous Pt, while the oxygen fuel side on the right side is oxygen The fuel flow path 85 is in contact with the polymer electrolyte membrane 81 through the air electrode 84 made of porous Pt.
In the figure, reference numerals 86 and 87 denote main electrodes.

In this case, the H ₂ gas that has permeated the fuel electrode 82 on the hydrogen fuel side becomes protons (H ⁺ ) by the catalytic action of Pt constituting the fuel electrode 82, passes through the polymer electrolyte membrane 81, and flows into the oxygen fuel side air. An electromotive force is generated by reaching the electrode 84 and combining with oxygen to generate water (H ₂ O), thereby functioning as a fuel cell. By increasing the opposing electrodes, the surface area can be easily increased. There is a feature that you can.

The reaction formula on each electrode side is as follows.
Reaction on the hydrogen electrode side: H ₂ → 2H ⁺ + 2e ⁻
Reaction on the oxygen electrode side: 1 / 2O ₂ + 2H ⁺ + 2e ⁻ → H ₂ O

See FIG.
FIG. 26 is a conceptual configuration diagram of a conventional planar fuel cell, in which an electrode and a catalyst are provided in a pair of fuel channels formed on a silicon substrate 91, and the pair of fuel channels are connected to a polymer electrolyte membrane 98. It is covered with.

  In the figure, the left side is the hydrogen fuel side, and a fuel electrode 93 is provided so as to cover the inner wall of the hydrogen fuel channel 92 and the left surface of the silicon substrate 91, and the surface of the fuel electrode 93 in the hydrogen fuel channel 92 is made Pt. Cover with catalyst 94.

  On the other hand, on the right oxygen fuel side, an air electrode 96 is provided so as to cover the inner wall of the oxygen fuel channel 95 and the right surface of the silicon substrate 91, and the surface of the air electrode 96 in the oxygen fuel channel 95 is covered with a Pt catalyst 97. It has a covered structure.

In this case, protons (H ⁺ ) formed in the vicinity of the fuel electrode 93 in the hydrogen fuel channel 92 pass through the polymer electrolyte membrane 98 and form an air electrode in the vicinity of the oxygen fuel channel 95 on the opposite bank so as to draw an arc. It reaches 96 and functions as a fuel cell by being combined with oxygen and forming water.

  In this structure, since the flow paths and electrodes are planarly formed on the surface of the substrate, it is possible to apply a planar manufacturing technique that has been stacked for a long time for integrated circuit (LSI) manufacturing in semiconductor manufacturing technology. Therefore, it is not necessary to proceed with development from the beginning from the beginning, and rapid evolution can be expected.

  In addition, it is possible to use existing equipment for semiconductors, and in some cases, it is possible to utilize semiconductor manufacturing plants that have become obsolete. An increase in surface area due to complication becomes possible.

As a result, it is expected to be connected to a small and high-power fuel cell that can be mounted on a portable PC mobile phone at an early stage.
In addition, if a fuel cell can be formed in the same way as a semiconductor manufacturing method, there is a possibility that a fuel cell and a semiconductor device can be mixed together in the future. An ultra-compact device that integrates a fuel cell and an electronic circuit. There is also a possibility that an intelligent fuel cell with a fuel cell control circuit and a fuel status monitoring circuit built in together.

On the other hand, it has also been proposed to use oriented carbon nanotubes as electrodes in order to increase the efficiency of fuel cells (see, for example, Patent Document 1 or Patent Document 2).
JP 2004-103403 A JP 2004-063200 A

  However, considering future electronic devices, it is expected that power consumption will increase significantly due to performance improvements, higher functionality, and multi-functionality. A fuel cell is expected to be required.

  For example, wearable computers that are fast, high-functional and multi-functional, and are light and thin, always wearable (and collectively), 3D TV phones, wallet functions, etc. Sensor tags that detect and notify environmental information, and humanoid robots that work on behalf of humans for long periods of time require high power and require a fuel cell in a limited space. must not.

  In this way, in the future, a smaller, higher-power fuel cell will be required, and the price will not be cheap, so it will not spread to the market, and manufacturing companies will not be able to make profits. Although it is considered desirable, it is difficult to solve such problems with the current technology.

  For example, in the case of the above-mentioned counter electrode type fuel cell, if the opposing electrode is enlarged, the surface area can be easily increased and it can cope with a large output, but the device itself is also large and is not suitable for miniaturization. There is a problem.

Also, if the opposing electrode is made larger, the distance between the main electrode 87 and the position where the H ions and O ₂ have reacted by consuming electrons becomes longer, so that the parasitic resistance increases when electrons flow and the output increases. There is a problem of hindering.

  Further, in the case of the planar type fuel cell described above, the upper end of the flow path functions only as a fuel cell, so that there is a problem that the output is inferior and it is difficult to achieve high power.

  Furthermore, in the case of the fuel cell using the above-mentioned carbon nanotube, there is a problem that it cannot satisfy the demand for small size and high output because it only improves the electrode performance.

  Therefore, an object of the present invention is to achieve both miniaturization and high output.

FIG. 1 is a diagram illustrating the basic configuration of the present invention. Means for solving the problems in the present invention will be described with reference to FIG.
Reference numeral 6 in the figure denotes catalyst fine particles such as Pt that perform a catalytic reaction for functioning as a fuel cell.
In order to solve the above-described problem, the present invention provides a fuel flow path that also serves as a fuel electrode composed of a large number of carbon nanotubes arranged in a direction perpendicular to the main surface of the substrate 1 with a minute gap in the fuel cell. The counter electrode 3 and the oxidant channel / electrode 4 also serving as the oxidant electrode are provided to face each other, and the electrolytic membrane 5 is provided to fill at least the facing gap between the fuel channel / electrode 3 and the oxidant channel / electrode 4. It is characterized by that.

  As described above, the present invention is a unique fuel cell structure in which the planar structure and the counter electrode structure are integrated. However, since it is basically a planar structure, conventional semiconductor technology can be applied and the side surface of the counter electrode is used. Compared with the conventional planar type, the surface area can be remarkably increased, thereby realizing a small and high-power fuel cell.

  In this case, since the carbon nanotube alignment film itself becomes the flow path and electrode, not only can the process be shortened, but it is not necessary to create a useless space that is neither the flow path nor the electrode. An efficient fuel cell can be utilized.

  In addition to increasing the surface area of the fuel cell by utilizing the uneven surface formed at the interface between the carbon nanotube alignment film surface and the polymer film, the carbon nanotubes are aligned and grown vertically from the substrate 1 in a self-aligned manner. However, since a high-aspect and steep three-dimensional structure can be formed, the surface area can be remarkably increased by using the side wall of this three-dimensional structure.

In addition, since the distance between the H ion, O ₂ , the reaction site, and the base electrode serving as the extraction electrode is inevitably shortened, the parasitic resistance can be reduced, thereby reducing the internal resistance. It becomes possible.

  In addition, when trying to form such a steep, high-aspect three-dimensional electrode structure with the conventional technology, the resist will be worn out only by the resist pattern and cannot withstand etching, so a hard mask material is formed on the surface, and the resist and pattern It is necessary to perform etching using the mask, once the resist pattern is transferred to a hard mask material to form a hard mask, and then to further etch the base electrode using the hard mask as a mask.

  Moreover, deep and steep etching of several hundred μm is practically impossible with conventional semiconductor technology, and we must start by developing special etching equipment. Even if it can be overcome, it takes a long time to form a deep structure, and it cannot be expected to reduce the price.

  Further, in this case, the fuel channel / electrode 3 and the oxidant channel / electrode 4 made of carbon nanotubes may have the same overall density, but the density of the inner carbon nanotubes is higher than the density of the outer carbon nanotubes. It may be made low, thereby increasing the conductance.

  Furthermore, the inside of the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 made of carbon nanotubes may be formed as cavities in which no carbon nanotubes exist, thereby further increasing the conductance.

  In the above-described configuration, an electrolytic membrane that fills the tops of the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 made of carbon nanotubes with the gap between the fuel flow channel electrode 3 and the oxidant flow channel electrode 4. 5 may be covered with the electrolytic membrane 5 integrated with the carbon nanotube 5, or may be closed with the carbon nanotubes themselves constituting the fuel flow path / electrode 3 and the oxidant flow path / electrode 4. The contact surface with the top portion of the oxidant channel / electrode 4 may be closed by a substrate that is at least insulated, and may be appropriately selected depending on the density of the carbon nanotube alignment film or the viscosity of the electrolytic film 5. .

  Further, when carbon nanotubes are grown, a catalyst such as Co is required as a growth base, so that a catalyst metal layer is provided as the base 2 of the fuel flow path / electrode 3 and the oxidant flow path / electrode 4, or It is necessary to use the non-catalytic metal layer and the catalyst electrode thin film provided thereon as the base 2, or further, use the non-catalytic metal layer and the conductive catalyst fine particles deposited thereon as the base 2.

  Further, at least one of the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 meanders in a planar shape, and the other of the fuel flow channel electrode 3 and the oxidant flow rate electrode 4 meanders. It is desirable to arrange so as to be inserted between the electrodes, whereby the total facing area between the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 can be greatly increased.

  The supply of fuel and oxidant causes the fuel to flow in the direction perpendicular to the orientation direction of the carbon nanotubes in the fuel flow channel / electrode 3 and is orthogonal to the orientation direction of the carbon nanotubes in the oxidant flow channel / electrode 4. An oxidant may be allowed to flow in the direction, and the configuration of the electrodes is simplified by using the gaps that stand in the forest as the flow paths.

  Alternatively, fuel or oxidant is supplied from one end of the orientation direction of the carbon nanotube to one of the fuel passage / electrode 3 and the oxidant passage / electrode 4, and the other is a direction orthogonal to the orientation direction of the carbon nanotube. The fuel or the oxidant may be supplied from the fuel, which is particularly effective when a liquid fuel such as alcohol is used as the fuel.

  According to the present invention, since it is basically a planar structure, it is possible to apply a highly developed semiconductor integrated technology, and rapid development can be expected, as well as downsizing of the device and integration with an electronic circuit. In addition, the carbon nanotube alignment film is used as a channel and electrode, so the surface area is increased by the uneven shape formed at the interface with the polymer electrolyte membrane, and the high aspect and steep 3D structure unique to carbon nanotubes. A double effect of increasing the surface area due to the use of the side wall of the fuel cell can be expected, and a small and high-power fuel cell becomes possible.

  The present invention provides a fuel cell electrode having a three-dimensional structure composed of an alignment film in which carbon nanotubes are arranged vertically with respect to a substrate, and also serves as a flow path, and also defines the thickness of a polymer electrolyte membrane It is also used.

Here, with reference to FIG. 2 thru | or FIG. 4, the manufacturing process of the fuel cell of Example 1 of this invention is demonstrated.
See Figure 2
First, a Co layer serving as a catalyst is deposited on the substrate 11 made of SiO ₂ and then etched using a resist pattern to form, for example, catalytic metal layers 12 and 13 having a width of 200 μm.
In this case, as shown in the plan view of the middle stage, the catalyst metal layer 12 has a meandering pattern, while the catalyst metal layer 13 has a plurality of patterns inserted between the meandering catalyst metal layers 12.

  In this case, the distance between the catalyst metal layer 12 and the catalyst metal layer 13 is that the thickness of the polymer electrolyte membrane 17 is defined by the gap between the fuel electrode and the air electrode of the fuel cell, as will be described later. Therefore, the interval may be determined in accordance with the required thickness of the polymer electrolyte membrane, and is currently about 200 μm, for example.

Next, the carbon nanotube three-dimensional structures 14 and 15 are grown at 450 ° C. by using, for example, acetylene gas as a source gas by using the CVD method.
In this case, since the carbon nanotubes grow selectively only in the presence of the catalyst metal and do not grow in other regions, the carbon nanotube three-dimensional structures 14 and 15 grow on the catalyst metal layers 12 and 13, respectively. .

Further, the three-dimensional structure of carbon nanotubes 14 and 15 grows vertically on the catalyst metal layers 12 and 13 with respect to the substrate 11, and the growth rate is very fast. Therefore, it can grow very thick.
During this time, since the carbon nanotubes hardly protrude in the lateral direction, the carbon nanotube three-dimensional structures 14 and 15 having a very steep and high-aspect three-dimensional structure are obtained.

See Figure 3
Next, for example, Pt fine particles 16 having a diameter of about several nanometers to several tens of nanometers that serve as a fuel cell catalyst are dispersed over the entire surface.
At this time, the Pt fine particles 16 adhere to the surfaces of the carbon nanotube three-dimensional structures 14 and 15 by van der Waals force and do not enter the carbon nanotube three-dimensional structures 14 and 15.

The Pt fine particles 16 are adsorbed on the surfaces of the carbon nanotube three-dimensional structures 14 and 15 by van der Waals force and do not move thereafter.
The Pt fine particles 16 in this case are provided in order to accelerate the formation of hydrogen ions (protons) by stripping electrons from hydrogen as a fuel by the catalytic action.

Next, the entire substrate 11 is immersed in dilute hydrofluoric acid to remove the oxide film (not shown) formed on the surface of the substrate 11, thereby removing the Pt fine particles 16 adhering to the substrate 11 by lift-off. To do.
Thus, by removing the Pt fine particles 16 adhering to the substrate 11, the carbon nanotube three-dimensional structure 14 and the carbon nanotube three-dimensional structure 15 that become the fuel electrode and the air electrode of the fuel cell are short-circuited via the Pt fine particles 16. There is no.

Since carbon nanotubes and Pt are not etched with diluted hydrofluoric acid, the Pt fine particles 16 attached to the surfaces of the carbon nanotube three-dimensional structures 14 and 15 remain as they are.
In addition, the carbon nanotubes after growth are extremely strong in water repellency, so they will not repel water and be bundled (become bundled).

See Figure 4
Next, for example, a solvent of a polymer electrolyte membrane made of DMAC (dimethyl acetate) + H ₂ O is applied on the entire surface, and cured by performing a heat treatment at 150 ° C. to 200 ° C. for 30 minutes in a nitrogen gas atmosphere. The molecular electrolyte membrane 17 is used.

  In this case, since the solvent of the polymer electrolyte membrane 17 has viscosity, it cannot enter one or one gap between the carbon nanotubes, and is formed in a shape surrounding the carbon nanotube three-dimensional structures 14 and 15. .

  Next, the polymer electrolyte membrane 17 in the upper part of the portion that becomes the end of the flow path composed of the carbon nanotube three-dimensional structures 14 and 15 is selectively removed, and an opening that exposes the upper ends of the carbon nanotube three-dimensional structures 14 and 15 is formed. By providing the fuel and oxidant inlets 18 and 19 and the outlets 20 and 21, the basic structure of the fuel cell is completed.

By introducing H ₂ gas from the introduction port 18 of this fuel cell and introducing air as an oxidant from the introduction port 19, the H ₂ gas and air become the carbon nanotube three-dimensional structures 14 and 15, respectively. While flowing through the gap, the H ₂ gas is stripped of electrons by the catalytic action of the Pt fine particles 16 to become hydrogen ions H ⁺ , which travels through the polymer electrolyte membrane 17 to the carbon nanotube three-dimensional structure 15 that becomes the air electrode. And reacts with O ₂ to generate an electromotive force.

  As described above, in Example 1 of the present invention, since the electrodes made of carbon nanotubes, that is, the air electrode and the fuel electrode themselves are used as the fuel flow path and the oxidant flow path, the entire surface area of the flow path is effectively used. Since it can be used, it is possible to obtain a high output in spite of its small size, and the higher the aspect ratio of the carbon nanotube three-dimensional structures 14 and 15, the higher the output can be achieved.

  In Example 1 of the present invention, by using the growth characteristics unique to carbon nanotubes, it is possible to easily form a steep and high aspect ratio structure, which was difficult with conventional etching, in a very short process. .

  Further, in the first embodiment of the present invention, the fuel electrode is meandered and the air electrode is disposed therebetween, so that the total extension of the electrode can be lengthened, and thereby the total area that acts as a fuel cell. Can contribute to higher output.

Furthermore, in Example 1 of the present invention, since there is a specific effect by using the carbon nanotube three-dimensional structure as the fuel electrode and the air electrode, description will be given with reference to FIGS. See Figure 5
FIG. 5 is a cross-sectional view of a main part parallel to the substrate. In the vicinity of the surface of the carbon nanotube three-dimensional structure 15 (14) made of forested carbon nanotubes, the polymer electrolyte membrane 17 enters the carbon nanotubes and carbon nanotubes. Since the three-dimensional structure 15 (14) is in contact with the uneven surface instead of the flat surface, there is an effect of increasing the surface area of the fuel cell.

See FIG.
FIG. 6 is a cross-sectional view of the main part perpendicular to the substrate. Even in the vicinity of the top surface of the carbon nanotube three-dimensional structure 15 (14) made of forested carbon nanotubes, the polymer electrolyte membrane 17 enters the carbon nanotubes and carbon Since the three-dimensional structure 15 (14) is in contact with the uneven surface instead of the flat surface, there is an effect of increasing the surface area of the fuel cell.

  Therefore, by using the carbon nanotube three-dimensional structures 14 and 15 as the fuel electrode and the air electrode, the effect of increasing the surface area due to the contact of the polymer electrolyte membrane 17 with the uneven surface and the high aspect ratio carbon nanotube three-dimensional structures 14 and 15 are achieved. A double surface area increasing effect with a side area increasing effect is obtained.

Next, with reference to FIG.7 and FIG.8, the manufacturing process of the fuel cell of Example 2 of this invention is demonstrated. See FIG.
First, a Co layer serving as a catalyst is deposited on a substrate 31 made of SiO ₂ and then etched using a resist pattern to form catalyst metal layers 32 and 33 having the same pattern as in the first embodiment. To do.

Next, a resist pattern 34 having openings provided so that both ends of the patterned catalyst metal layers 32 and 33 are exposed is formed, and TiCo fine particles 35 containing about 20% of Ti having a diameter of several nm serving as a catalyst. To selectively adhere the TiCo fine particles 35 to the exposed portions of the catalytic metal layers 32 and 33.
In this case, the width of the adhesion region of the TiCo fine particles 35 is 10 to 50 μm.

  Next, by removing the resist pattern 34 with an organic solvent, the TiCo fine particles 35 on the resist pattern 34 are lifted off together with the resist pattern 34, and then the carbon nanotubes are grown under the same growth conditions as in the first embodiment. The three-dimensional structures 36 and 37 are grown.

  At this time, the density of the carbon nanotubes grown on the catalytic metal layers 32 and 33 made of Co is lower than the density of the carbon nanotubes grown in the region where the TiCo fine particles 35 are adhered due to the difference in the catalytic action of Co and TiCo. The fuel and oxidant easily flow inside.

Refer to FIG. 8. Thereafter, as in Example 1, after attaching Pt fine particles 38 to the surfaces of the three-dimensional structures 36 and 37 of the carbon nanotubes, a solvent for the polymer electrolyte membrane 39 was applied over the entire surface, and in a nitrogen gas atmosphere The polymer electrolyte membrane 39 is cured by heat treatment at 150 ° C. to 200 ° C. for 30 minutes.

In this case, although the density is low, carbon nanotubes also grow inside the three-dimensional structures 36 and 37 of the carbon nanotubes, so that the viscosity of the polymer electrolyte membrane 39 is utilized at the upper end as in the first embodiment. The lid can be closed.
In this case, in order to compensate for the low internal density, it is desirable to devise in advance such as increasing the viscosity of the polymer electrolyte membrane 39 or further increasing the curing time.

  Next, although not shown in the drawing, the polymer electrolyte membrane 39 is selectively removed from the upper part of the portion that becomes the end of the flow path composed of the carbon nanotube three-dimensional structures 36, 37, and the upper ends of the carbon nanotube three-dimensional structures 36, 37 are removed. The basic structure of the fuel cell is completed by providing an opening that exposes the gas and providing an inlet and outlet for fuel and oxidant.

  Thus, in Example 2 of the present invention, the conductance (viscous resistance) is increased because the density of carbon nanotubes is provided inside and outside by utilizing the difference in the catalytic action of the base during the growth process, Compared with the first embodiment, the fuel and the oxidant easily flow, and even when a liquid fuel such as methanol is used as the fuel, the fuel can flow smoothly.

Next, with reference to FIG.9 and FIG.10, the manufacturing process of the fuel cell of Example 3 of this invention is demonstrated.
See FIG.
First, after depositing a Co layer serving as a catalyst on a substrate 41 made of SiO ₂ , etching is performed using a resist pattern, so that a meandering pattern between the meandering pattern and the meandering pattern as shown in the plan view in the above figure is obtained. The catalyst metal layers 42 and 43 having the line pattern inserted in are formed.
In this case, the width of the pair of catalyst metal layers 42 and the pair of catalyst metal layers 43 is, for example, 200 μm, and the width of each of the catalyst metal layers 42 and 43 is set to 80 μm. The width is set to 40 μm.

Next, carbon nanotubes are grown under the same growth conditions as in Example 1 to grow the carbon nanotube three-dimensional structures 44 and 45.
At this time, the three-dimensional structure of the carbon nanotubes 44 and 45 grows only on the catalyst metal layers 42 and 43, and a space where the carbon nanotubes do not grow is formed between the pair of catalyst metal layers 42 and between the pair of catalyst metal layers 43.

Next, after the top surfaces of the carbon nanotube three-dimensional structures 44 and 45 are covered with a stencil mask 46, the Pt fine particles 47 are sprayed to attach the Pt fine particles 47 only to the outer walls of the carbon nanotube three-dimensional structures 44 and 45. .

Next, a solvent for the polymer electrolyte membrane is applied to the entire surface, and cured by performing a heat treatment at 150 ° C. to 200 ° C. for 30 minutes in a nitrogen gas atmosphere to obtain a polymer electrolyte membrane 48.
At this time, if the solvent of the polymer electrolyte membrane 48 is applied to the surface all at once, air bubbles remain between the carbon nanotubes, so that the polymer electrolyte membrane 48 does not penetrate deep into the flow path, and polymer electrolyte The film 48 can be formed.

  Next, although not shown in the drawing, the polymer electrolyte membrane 48 at the upper part of the portion that becomes the end of the channel composed of the carbon nanotube three-dimensional structures 44, 45 is selectively removed, and the upper ends of the carbon nanotube three-dimensional structures 44, 45 are removed. The basic structure of the fuel cell is completed by providing an opening that exposes the gas and providing an inlet and outlet for fuel and oxidant.

  In this way, in Example 3 of the present invention, the inside of the carbon nanotube three-dimensional structures 44 and 45 is made into a complete cavity by making the catalytic metal layers 42 and 43 into hollow patterns. Since the conductance is higher than 2 and the fuel and the oxidant easily flow, the fuel can flow smoothly even when a liquid fuel such as methanol is used as the fuel.

Next, a fuel cell of Example 4 of the present invention will be described with reference to FIG. 11. Since Example 4 is a modification of Example 3 described above, only the cross-sectional structure of the electrode pattern will be described.
See FIG.
FIG. 11 is a cross-sectional view of an electrode pattern of Example 4 of the present invention, in which non-catalytic metal layers 49 and 50 made of Al are formed in the same pattern as in Example 1 above on a substrate 41 made of SiO ₂ . Thereafter, catalytic metal layers 51 and 52 made of Co thin film each having a width of 80 μm are provided on the periphery thereof, and the subsequent steps are performed in exactly the same manner as in the third embodiment.

  In the fourth embodiment, since the non-catalytic metal layers 49 and 50 having a small specific resistance are used as the base of the catalytic metal layers 51 and 52, the parasitic resistance of the fuel electrode and the air electrode itself can be reduced. In this respect, the output can be increased as compared with the third embodiment.

Next, a fuel cell of Example 5 of the present invention will be described with reference to FIG. 12. Since Example 5 is also a modification of Example 3 described above, only the cross-sectional structure of the electrode pattern will be described.
See FIG.
FIG. 12 is a cross-sectional view of an electrode pattern of Example 5 of the present invention, in which non-catalytic metal layers 49 and 50 made of Al are formed in the same pattern as in Example 1 above on a substrate 41 made of SiO ₂ . Thereafter, Co fine particles 53 serving as a catalyst are attached to the periphery of each region in a region having a width of 80 μm by using the lift-off method in the same manner as in Example 2 above, and the subsequent steps are completely the same as in Example 3 above. Do the same.

Also in the fifth embodiment, the parasitic resistance of the fuel electrode and the air electrode itself can be reduced as in the fourth embodiment, and in this respect, higher output can be achieved than in the third embodiment.
In this case, the diameter of the Co fine particles 53 is about several nanometers, which is a size of several thousandths of the width of 80 μm.

Next, with reference to FIGS. 13 to 15, the manufacturing process of the fuel cell of Example 6 of the present invention will be described.
See FIG.
First, after depositing a Co layer serving as a catalyst on a substrate 61 made of SiO ₂ , etching is performed using a resist pattern, so that a meandering pattern between the meandering pattern and the meandering pattern is shown as a plan view in the above figure. Catalyst metal layers 62 and 63 each having a line pattern inserted in are formed.
In this case, the outer space between the pair of catalyst metal layers 62 and the outer space between the pair of catalyst metal layers 63 are, for example, 200 μm, and the width of each of the catalyst metal layers 62 and 63 is 5 μm. The width of the central exposed part is 190 μm.

Next, carbon nanotubes are grown under the same growth conditions as in Example 1 to grow the carbon nanotube three-dimensional structures 64 and 65.
At this time, the three-dimensional structure of the carbon nanotubes 64 and 65 grows only on the catalyst metal layers 62 and 63, and a wide space where the carbon nanotubes do not grow is formed between the pair of catalyst metal layers 62 and between the pair of catalyst metal layers 63. .

Next, as in Example 3, the top surfaces of the carbon nanotube three-dimensional structures 64 and 65 are covered with a stencil mask 66, and then the Pt fine particles 67 are dispersed, whereby the outer walls of the carbon nanotube three-dimensional structures 64 and 65 are dispersed. Pt fine particles 67 are attached only to the surface.

  Next, using the stencil mask 68, the solvent of the polymer electrolyte 69 is poured into a portion other than the flow path between the carbon nanotube three-dimensional structures 64 and 65.

See FIG.
Subsequently, when the polymer electrolyte membrane 69 is poured between the outer walls of the three-dimensional structure of the carbon nanotubes 64 and 65 and the liquid level of the polymer electrolyte membrane 69 becomes higher, the three-dimensional structure of the carbon nanotube is formed by the weight of the polymer electrolyte membrane 69. The outer walls of the structures 64 and 65 begin to bend, and the outer walls of the carbon nanotube three-dimensional structures 64 and 65 come into contact with each other to form an arched tunnel.
Once the arch is formed, this arched structure is highly durable and is less likely to collapse.

  If the polymer electrolyte membrane 69 is continuously poured, the arched cavity is completely filled with the polymer electrolyte membrane 69, and then heat treatment is performed at 150 ° C. to 200 ° C. for 30 minutes in a nitrogen gas atmosphere. The polymer electrolyte membrane 69 is thus cured.

  At this time, although explanation is omitted, by setting the width of each of the catalytic metal layers 62 and 63 to 80 μm at the fuel and air inlet and outlet as in the third embodiment, no arch is formed in the vicinity thereof. Since the polymer electrolyte membrane 69 is covered, the polymer electrolyte membrane 69 in this portion is selectively removed, and an opening that exposes the upper end portions of the carbon nanotube three-dimensional structures 64 and 65 is formed. The basic structure of the fuel cell is completed by providing the fuel and the oxidant inlet and outlet.

  As described above, in Example 6 of the present invention, since the cavities of the carbon nanotube three-dimensional structures 64 and 65 are widened, the conductance becomes higher than that in Example 3 and the three-dimensional structure of carbon nanotubes 64 and 65 is obtained. The polymer electrolyte membrane 69 does not enter the inside because the top portion is closed in an arch shape.

Next, with reference to FIG. 16 thru | or FIG. 17, the manufacturing process of the fuel cell of Example 7 of this invention is demonstrated.
See FIG.
First, in exactly the same manner as in Example 3, after depositing a Co layer serving as a catalyst on a substrate 41 made of SiO ₂ , catalytic metal layers 42 and 43 are formed by etching using a resist pattern.

  Next, carbon nanotubes are grown under the same growth conditions as in Example 1 to grow the carbon nanotube three-dimensional structures 44 and 45, and then the top surfaces of the carbon nanotube three-dimensional structures 44 and 45 are covered with a stencil mask 46. By spraying the Pt fine particles 47, the Pt fine particles 47 are attached only to the outer walls of the carbon nanotube three-dimensional structures 44 and 45.

See FIG.
Next, as in Example 6 above, using the stencil mask 54, the solvent of the polymer electrolyte 48 was poured into a portion other than the flow path between the carbon nanotube three-dimensional structures 44, 45, and then in a nitrogen gas atmosphere. The polymer electrolyte membrane 48 is cured by performing a heat treatment at 150 ° C. to 200 ° C. for 30 minutes.

Next, the insulating substrate 55 made of low-melting glass and the substrate 41 with the flow channel structure are inserted in a vacuum chamber (not shown), and then lightly evacuated to about 10 ⁻² Torr to bring the two substrates into close contact with each other. .

  Next, both substrates are heated at 200 ° C. to 400 ° C. to soften the low-melting glass constituting the insulating substrate 55, so that the insulating substrate 55 is formed on the tops of the carbon nanotube three-dimensional structures 44 and 45 and the upper surface of the polymer electrolyte membrane 48. By adhering to each other, a flow path surrounded by carbon nanotubes is completed.

  Next, although not shown in the figure, the insulating substrate 55 is selectively removed at the upper part of the portion that becomes the end of the flow path composed of the carbon nanotube three-dimensional structures 44, 45, and the upper ends of the carbon nanotube three-dimensional structures 44, 45 are exposed. The basic structure of the fuel cell is completed by providing an opening to be used as an inlet and an outlet for the fuel and oxidant.

  Thus, in Example 7 of the present invention, the insulating substrate 55 made of low-melting glass is used as a “lid” for closing the flow path, so that the polymer electrolyte membrane is inside the carbon nanotube three-dimensional structures 44, 45. There is no risk of entering the channel and reducing the cross-sectional area of the flow path.

Next, with reference to FIG. 18, the manufacturing process of the fuel cell of Example 8 of the present invention will be described.
See FIG.
First, in exactly the same manner as in Example 7, after depositing a Co layer serving as a catalyst on a substrate 41 made of SiO ₂ , catalytic metal layers 42 and 43 are formed by etching using a resist pattern.

  Next, carbon nanotubes are grown under the same growth conditions as in Example 1 to grow the carbon nanotube three-dimensional structures 44 and 45, and then the top surfaces of the carbon nanotube three-dimensional structures 44 and 45 are covered with a stencil mask 46. By spraying the Pt fine particles 47, the Pt fine particles 47 are attached only to the outer walls of the carbon nanotube three-dimensional structures 44 and 45.

Next, the insulating substrate 55 made of low-melting glass and the substrate 41 on which the carbon nanotube three-dimensional structures 44 and 45 are formed are inserted into a vacuum chamber (not shown), and then lightly evacuated to about 10 ⁻² Torr. Adhere the substrate.

  Next, both substrates are heated at 200 ° C. to 400 ° C. to soften the low-melting glass constituting the insulating substrate 55, and the insulating substrate 55 is adhered to the tops of the three-dimensional structures 44 and 45 of the carbon nanotubes. The flow path surrounded by the periphery is completed.

  Next, after the solvent of the polymer electrolyte 48 is poured into a portion other than the flow path between the carbon nanotube three-dimensional structures 44 and 45, curing is performed by performing a heat treatment at 150 ° C. to 200 ° C. for 30 minutes in a nitrogen gas atmosphere. Thus, the polymer electrolyte membrane 48 is obtained.

  Next, although not shown in the figure, the insulating substrate 55 is selectively removed at the upper part of the portion that becomes the end of the flow path composed of the carbon nanotube three-dimensional structures 44, 45, and the upper ends of the carbon nanotube three-dimensional structures 44, 45 are exposed. The basic structure of the fuel cell is completed by providing an opening to be used as an inlet and an outlet for the fuel and oxidant.

  As described above, in Example 8 of the present invention, the tops of the carbon nanotube three-dimensional structures 44 and 45 are covered with the insulating substrate 55 before pouring the polymer electrolyte membrane, so that the polymer can be used without using a stencil mask. Since the electrolytic membrane can be injected, the manufacturing process is simplified.

Next, the fuel cell of Example 9 of the present invention will be described with reference to FIG. 19, but the basic manufacturing process is exactly the same as that of Example 1 described above, and the fuel introduction port is opened at the entire upper surface. Only the final structure will be described.
See FIG.
After manufacturing the structure shown in the lower diagram of FIG. 4 of Example 1 above, the polymer electrolyte membrane 17 on the entire upper part of the fuel flow path made of the carbon nanotube three-dimensional structure 14 is removed to form the fuel inlet 22 simultaneously. The polymer electrolyte membrane 17 in the upper part of the end portion of the oxidant flow path composed of the carbon nanotube three-dimensional structure 15 is removed to form an oxidant introduction port 19 and a discharge port 21.

  In particular, when alcohol and oxygen are used as fuel, the alcohol is liquid and difficult to flow in the narrow flow path, so air flows through a narrow tube, and the fuel cell is immersed in the alcohol liquid used as fuel. This is effective.

  Thus, in Embodiment 9 of the present invention, the fuel is supplied to the entire surface from above, so that the fuel can be easily guided to the fuel cell portion at a short distance, and the efficiency is improved.

Next, the fuel cell of Example 10 of the present invention will be described with reference to FIG. 20, but the basic manufacturing process is exactly the same as that of Example 2 described above, and the fuel introduction port is opened at the entire upper surface. Only the final structure will be described.
See FIG.
After manufacturing the structure shown in the lower diagram of FIG. 8 of Example 2 above, the polymer electrolyte membrane 39 in the entire upper part of the fuel flow path composed of the carbon nanotube three-dimensional structure 36 is removed to form the fuel inlet 40, The polymer electrolyte membrane 39 in the upper part of the end portion of the oxidant flow path made of the carbon nanotube three-dimensional structure 37 is removed to form an oxidant inlet and outlet.

  As described above, in the tenth embodiment of the present invention, as in the ninth embodiment, since the fuel is supplied to the entire surface from above, the fuel can be easily guided to the fuel cell unit at a short distance, Efficiency is improved.

Next, the fuel cell of Example 11 of the present invention will be described with reference to FIG. 21, but the basic manufacturing process is exactly the same as that of Example 3 described above, and the fuel introduction port is opened at the entire upper surface. Only the final structure will be described.
See FIG.
After manufacturing the structure shown in the lower diagram of FIG. 10 of Example 3 above, the polymer electrolyte membrane 48 is removed from the entire upper part of the fuel flow path composed of the carbon nanotube three-dimensional structure 44 to form the fuel inlet 56 simultaneously. The polymer electrolyte membrane 48 in the upper part of the end portion of the oxidant flow path composed of the carbon nanotube three-dimensional structure 45 is removed to form an oxidant inlet and outlet.

  As described above, in the eleventh embodiment of the present invention, as in the ninth embodiment, since the fuel is supplied to the entire surface from above, the air can be easily led to the fuel cell portion at a short distance, Efficiency is improved.

Next, the fuel cell of Example 12 of the present invention will be described with reference to FIG. 22, but the basic manufacturing process is exactly the same as that of Example 6 described above, and the fuel introduction port is opened at the entire upper surface. Only the final structure will be described.
See FIG.
After manufacturing the structure shown in the lower diagram of FIG. 15 in Example 6 above, the polymer electrolyte membrane 69 on the entire upper part of the fuel flow path composed of the carbon nanotube three-dimensional structure 64 is removed to form the fuel inlet 70 simultaneously. The polymer electrolyte membrane 69 in the upper part of the end portion of the oxidant flow path made of the carbon nanotube three-dimensional structure 65 is removed to form an oxidant inlet and outlet.

  As described above, in the twelfth embodiment of the present invention, as in the ninth embodiment, since the fuel is supplied to the entire surface from above, the air can be easily guided to the fuel cell portion at a short distance, Efficiency is improved.

Next, the fuel cell of Example 13 of the present invention will be described with reference to FIG. 23, but the basic manufacturing process is exactly the same as that of Example 7 described above, and the fuel inlet is the upper entire surface opening. Only the final structure will be described.
See FIG.
After the structure shown in the lower diagram of FIG. 17 of Example 7 is manufactured, the insulating substrate 55 in the entire upper part of the fuel flow path composed of the carbon nanotube three-dimensional structure 44 is removed to form the fuel introduction port 57 and at the same time, the carbon nanotube The insulating substrate 55 in the upper part of the end portion of the oxidant flow path composed of the three-dimensional structure 45 is removed to form an oxidant introduction port and a discharge port.

  As described above, in the thirteenth embodiment of the present invention, as in the ninth embodiment, since the fuel is supplied to the entire surface from above, the air can be easily guided to the fuel cell portion at a short distance, Efficiency is improved.

Next, the fuel cell of Example 14 of the present invention will be described with reference to FIG. 24, but the basic manufacturing process is exactly the same as that of Example 1 described above, and the air inlet is the entire upper surface opening. Only the final structure will be described.
See FIG.
After the structure shown in the upper diagram of FIG. 4 of Example 1 is manufactured, the polymer electrolyte membrane 17 at the upper part of the end of the fuel flow path composed of the carbon nanotube three-dimensional structure 14 is removed to remove the fuel inlet 18 and the exhaust. At the same time when the outlet 20 is formed, the polymer electrolyte membrane 17 in the entire upper part of the oxidant flow path made of the carbon nanotube three-dimensional structure 15 is removed to form an oxidant inlet 23.

  Thus, in Example 14 of the present invention, since air is supplied to the entire surface from above, oxygen that is abundant in the air can be used effectively.

  The embodiments of the present invention have been described above, but the present invention is not limited to the conditions and configurations described in the embodiments, and various modifications are possible. For example, in the above embodiments, Co or TiCo is used as a catalyst metal for carbon nanotube growth, but is not limited to Co or TiCo, transition metals such as Co, Ni, Fe, etc., or a mixed alloy thereof, and further An alloy containing a part of these transition metals may be used.

  In each of the above embodiments, in order to grow carbon nanotubes, the base electrode pattern serving as the growth substrate is formed of a metal having a catalytic action, but in essence, the surface layer of the base electrode pattern serves as a catalyst. As long as the substance is present, a base electrode pattern is generally formed of a low-resistance non-catalytic metal such as Al, Cu, or Ag without using a high-resistance catalyst metal. The catalyst metal film may be thinly formed, or the catalyst fine particles formed in advance may be sprayed on necessary portions on the non-catalyst metal using a mask such as a resist.

Further, in each of the above embodiments, a SiO ₂ substrate, that is, a quartz substrate or the like is used as the substrate, but the substrate is not limited to the SiO ₂ substrate, and an Si ₃ N ₄ substrate, an insulating ceramic substrate, or Other insulating substrates such as a heat resistant plastic substrate may be used.

  In Example 4 and the like described above, Al is used as the non-catalytic metal layer, but is not limited to Al, and other non-catalytic metals such as Cu or Ag may be used.

  Further, in each of the above embodiments, the fuel electrode is meandered and the air electrode is disposed between them, but conversely, the air electrode may be meandered and the fuel electrode may be disposed between them. In this case, the total area acting as a fuel cell can be gained, which can contribute to higher output.

  Furthermore, both the fuel electrode and the air electrode may be meandered so that one of them enters the other, or both the fuel electrode and the air electrode may be comb-like to combine the tooth portions. Is also good.

  Further, in each of the above embodiments, the Pt fine particles adhering to the substrate between the air electrode and the fuel electrode are removed, whereas the distance between the air electrode and the fuel electrode is 200 μm, Since the size of the Pt fine particles is very small, if the density of the Pt fine particles is not so high, the Pt fine particles are not completely connected between the electrodes to form a current path. Therefore, it is not always necessary to remove the Pt fine particles. Absent.

  In each of the above embodiments, Pt is used as a catalyst for the fuel cell. However, since Pt is very expensive, various types of medium metals have been researched and developed, and will continue to appear in the future. Of course, you can use anything that works the same way.

In each of the above embodiments, gaseous H ₂ is used as the fuel. However, the fuel is not limited to H ₂ , and liquid fuel such as methanol or ethanol may be used.
In the case of liquid fuel, the flow of the liquid is likely to be obstructed by the carbon nanotubes, but the amount of power generation is small, so that the flow rate of the fuel may be small, or there are many flow paths and the flow per one There is no problem when the flow rate is small, and in particular, there is no problem at all in the case of the ninth to thirteenth embodiments.

  In each of the above embodiments, air is supplied and oxygen in the air is used as an oxidizing agent. However, the present invention is not limited to air, and oxygen gas may be supplied directly.

  In each of the above embodiments, the thickness of the polymer electrolyte membrane prevents crosstalk from preventing the fuel and oxidant from diffusing into the other region, and causes breakdown of the voltage generated in the fuel cell. However, it is not limited to 200 μm or more, and it may become thinner in the future with the development of technology.

  In Example 2 described above, Co is used as catalyst fine particles for growing carbon nanotubes, but is not limited to Co, and is not limited to Co, Ni, Fe or other transition metals, or Co, Ni, Fe. Alternatively, a mixed alloy of transition metals such as TiCo or an alloy such as TiCo partially containing these transition metals may be used.

  Further, instead of the catalyst fine particles, a transition metal such as Co, Ni, Fe or the like having a thickness of several nm, or a mixed alloy thereof, or a sputtered thin film or a CVD thin film of an alloy partially containing these transition metals. May be used.

  Further, in Example 3 above, the solvent of the polymer electrolyte membrane 48 is applied all at once, but the opening formed inside the three-dimensional structure of the carbon nanotube is made narrow, or the viscosity is adjusted appropriately. It can be applied at a normal speed by adjusting the temperature so as to be cured quickly after application.

In each of the above embodiments, the solvent of the polymer electrolyte membrane is composed of MDAC + H ₂ O. However, the solvent is not limited to MDAC + H ₂ O, but is not limited to MDAC + H ₂ O, but is DMSO (dimethylsulfide) + H ₂ O, or DMF (dimethylformamide). ) Solvents of other polymer electrolyte membranes such as + H ₂ O may be used.

  In Example 3 or Example 6 or the like, since Pt is expensive, catalyst fine particles are selectively attached only to the outer surface of the carbon nanotube three-dimensional structure using a stencil mask. Therefore, the flow of fuel gas or liquid is not hindered, and since the Pt fine particles are formed inside the flow path, no electrical inconvenience is caused. It may be attached.

  In Example 6 described above, in order to make the carbon nanotube easily bend left and right, the region where the carbon nanotube grows is set to about 5 μm. This is because the strength (thickness, number of layers) of the carbon nanotube, the length of the carbon nanotube Therefore, it is preferable to adjust the region where the carbon nanotubes grow so as to obtain an appropriate bend appropriately.

  In Example 3 and the like described above, the polymer electrolyte membrane is poured into only a necessary portion using a stencil mask, but it may be dropped at a necessary portion using a pipette having a very thin tip. Alternatively, polymer electrolyte droplets may be injected using an ink jet nozzle.

  In the above-described embodiment 14, the shape corresponding to the embodiment 1 is described as a representative, but such a configuration is similarly applied to the above-described embodiments 2 to 8. It is.

  In Example 1 and the like described above, the catalyst metal layer is used as the growth base. However, the present invention is not limited to such a configuration, and a non-catalytic metal layer provided with a catalyst electrode thin film is used as the base. Alternatively, a non-catalytic metal layer having conductive catalyst fine particles attached thereto may be used as a base.

Further, the arch is formed by the carbon nanotube only in the above-described Example 6, but the arch may be formed by the carbon nanotube also in Example 1 or Example 2 or the like. Even if the density of the carbon nanotubes is uniform, arching is possible by reducing the density itself.
In these cases as well, the fuel and air may be supplied from the end portion or from the upper entire opening.

In addition, the top part of the carbon nanotube is covered with the insulating substrate only in the above-described Example 7 and Example 8, but also in Example 1 to Example 6, the top part of the carbon nanotube is covered with the insulating substrate instead of the polymer electrolyte membrane. It can be covered.
In these cases as well, the fuel and air may be supplied from the end portion or from the upper entire opening.

  Further, in the description of each of the above embodiments, a single-layer fuel cell is described. However, the above-described substrates may be stacked to form a multilayer, thereby further increasing the number of substrates. High voltage and high output are possible.

The detailed features of the present invention will be described again with reference to FIG. 1 again.
Again see Figure 1
(Additional remark 1) The fuel flow path and electrode 3 which also serves as the fuel electrode which consists of many carbon nanotubes arranged in a perpendicular direction with respect to the main surface of the substrate 1 and the oxidant flow path and electrode which also serves as the oxidant electrode 4 is provided so as to face each other, and at least an electrolytic membrane 5 that fills a gap between the fuel flow path and electrode 3 and the oxidant flow path and electrode 4 is provided.
(Supplementary note 2) The fuel cell according to Supplementary note 1, wherein in the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 made of carbon nanotubes, the density of the inner carbon nanotubes is lower than the density of the outer carbon nanotubes. .
(Supplementary note 3) The fuel cell according to supplementary note 1, wherein the inside of the fuel flow channel electrode 3 and the oxidant flow channel electrode 4 made of carbon nanotubes is a cavity free of carbon nanotubes.
(Additional remark 4) The top part of the fuel flow path electrode 3 and the oxidant flow path electrode 4 made of the carbon nanotube fills the facing gap between the fuel flow path electrode 3 and the oxidant flow path electrode 4. 4. The fuel cell according to any one of appendices 1 to 3, wherein the fuel cell is covered with an electrolytic membrane 5 integral with the membrane 5.
(Supplementary Note 5) The tops of the fuel flow channel / electrode 3 and the oxidant flow channel / electrode 4 made of the carbon nanotubes are closed by the carbon nanotubes themselves constituting the fuel flow channel / electrode 3 and the oxidant flow passage / electrode 4. 4. The fuel cell according to any one of supplementary notes 1 to 3, wherein the fuel cell is provided. (Supplementary Note 6) The tops of the fuel channel / electrode 3 and the oxidant channel / electrode 4 made of the carbon nanotubes are at least the contact surfaces of the fuel channel / electrode 3 and the top of the oxidant channel / electrode 4. 4. The fuel cell according to any one of appendices 1 to 3, wherein the fuel cell is closed by an insulated substrate.
(Supplementary note 7) The fuel cell according to any one of supplementary notes 1 to 6, wherein a catalyst metal layer is provided as a base 2 of the fuel flow channel electrode 3 and the oxidant flow channel electrode 4.
(Additional remark 8) The non-catalytic metal layer and the catalyst electrode thin film provided on it are used as the foundation | substrate 2 of the said fuel flow path electrode 3 and the oxidizing agent flow path electrode 4, The additional remark 1 thru | or 6 characterized by the above-mentioned The fuel cell according to any one of the above.
(Additional remark 9) The non-catalytic metal layer and the electroconductive catalyst fine particles adhering on it are used as the foundation | substrate 2 of the said fuel flow path electrode 3 and the oxidizing agent flow path electrode 4 The fuel cell according to any one of appendix 6.
(Appendix 10) One of the fuel flow path electrode 3 and the oxidant flow path electrode 4 is meandered in a planar shape, and the other of the fuel flow path electrode 3 and the oxidant flow path electrode 4 is meandered. 10. The fuel cell according to any one of appendices 1 to 9, wherein the fuel cell is disposed so as to be inserted between the flow path and electrode.
(Additional remark 11) While flowing a fuel in the direction orthogonal to the orientation direction of a carbon nanotube in the said fuel flow path and electrode 3, an oxidant in the direction orthogonal to the orientation direction of a carbon nanotube in the said oxidant flow path and electrode 4 11. The fuel cell according to any one of appendices 1 to 10, wherein
(Supplementary Note 12) Fuel or oxidant is supplied from one end of the orientation direction of the carbon nanotubes to one of the fuel passage / electrode 3 and the oxidant passage / electrode 4 and the other is oriented to the carbon nanotubes. 11. The fuel cell according to any one of appendices 1 to 10, wherein fuel or an oxidant is supplied from a direction orthogonal to each other.

  Examples of the use of the present invention include a wearable computer that can be always worn (bundled) with high speed and high functionality and multifunction, a mobile phone with a lot of functions such as a stereoscopic TV phone and a wallet function, rice grain, etc. The power supply of small devices such as sensor tags that detect and notify all environmental information with a size of a typical size is typical, but by multilayering, it can also be used as a power supply for devices such as humanoid robots that work on behalf of humans for a long time. Applicable.

It is explanatory drawing of the fundamental structure of this invention. It is explanatory drawing of the manufacturing process to the middle of the fuel cell of Example 1 of this invention. It is explanatory drawing of the manufacturing process to the middle of FIG. 2 after the fuel cell of Example 1 of this invention. It is explanatory drawing of the manufacturing process after FIG. 3 of the fuel cell of Example 1 of this invention. It is principal part sectional drawing parallel to the board | substrate of the fuel cell of Example 1 of this invention. It is principal part sectional drawing perpendicular | vertical to the board | substrate of the fuel cell of Example 1 of this invention. It is explanatory drawing of the manufacturing process to the middle of the fuel cell of Example 2 of this invention. It is explanatory drawing of the manufacturing process after FIG. 7 of the fuel cell of Example 2 of this invention. It is explanatory drawing of the manufacturing process to the middle of the fuel cell of Example 3 of this invention. It is explanatory drawing of the manufacturing process after FIG. 9 of the fuel cell of Example 3 of this invention. It is sectional drawing of the electrode pattern of Example 4 of this invention. It is sectional drawing of the electrode pattern of Example 5 of this invention. It is explanatory drawing of the manufacturing process to the middle of the fuel cell of Example 6 of this invention. It is explanatory drawing of the manufacturing process to the middle after FIG. 13 of the fuel cell of Example 6 of this invention. It is explanatory drawing of the manufacturing process after FIG. 14 of the fuel cell of Example 6 of this invention. It is explanatory drawing of the manufacturing process to the middle of the fuel cell of Example 7 of this invention. It is explanatory drawing of the manufacturing process after FIG. 16 of the fuel cell of Example 7 of this invention. It is explanatory drawing of the manufacturing process of the fuel cell of Example 8 of this invention. It is explanatory drawing of the fuel cell of Example 9 of this invention. It is explanatory drawing of the fuel cell of Example 10 of this invention. It is explanatory drawing of the fuel cell of Example 11 of this invention. It is explanatory drawing of the fuel cell of Example 12 of this invention. It is explanatory drawing of the fuel cell of Example 13 of this invention. It is explanatory drawing of the fuel cell of Example 14 of this invention. It is a notional block diagram of the conventional counter electrode type fuel cell. It is a conceptual block diagram of the conventional planar fuel cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Base 3 Fuel flow path / electrode 4 Oxidant flow path / electrode 5 Electrolytic membrane 6 Catalyst particulate 11 Substrate 12 Catalyst metal layer 13 Catalyst metal layer 14 Carbon nanotube three-dimensional structure 15 Carbon nanotube three-dimensional structure 16 Pt fine particle 17 Polymer electrolysis Membrane 18 Inlet 19 Inlet 20 Outlet 21 Outlet 22 Fuel Inlet 23 Oxidant Inlet 31 Substrate 32 Catalytic Metal Layer 33 Catalytic Metal Layer 34 Resist Pattern 35 TiCo Fine Particles 36 Carbon Nanotube Structure 37 Carbon Nanotube Structure 38 Pt Fine particles 39 Polymer electrolyte membrane 40 Fuel inlet 41 Substrate 42 Catalyst metal layer 43 Catalyst metal layer 44 Carbon nanotube three-dimensional structure 45 Carbon nanotube three-dimensional structure 46 Stencil mask 47 Pt fine particle 48 Polymer electrolyte membrane 49 Non-catalytic metal layer 50 Non-catalytic metal Layer 51 Catalyst gold Metal layer 52 Catalyst metal layer 53 Co fine particle 54 Stencil mask 55 Insulating substrate 56 Fuel inlet 57 Fuel inlet 61 Substrate 62 Catalyst metal layer 63 Catalyst metal layer 64 Carbon nanotube three-dimensional structure 65 Carbon nanotube three-dimensional structure 66 Stencil mask 67 Pt fine particle 68 Stencil mask 69 Polymer electrolyte membrane 70 Fuel inlet 81 Polymer electrolyte membrane 82 Fuel electrode 83 Hydrogen fuel channel 84 Air electrode 85 Oxygen fuel channel 86 Main electrode 87 Main electrode 91 Silicon substrate 92 Hydrogen fuel channel 93 Fuel electrode 94 Pt catalyst 95 Oxygen fuel flow path 96 Air electrode 97 Pt catalyst 98 Polymer electrolyte membrane

Claims (5)

A fuel flow path / electrode also serving as a fuel electrode composed of a large number of carbon nanotubes arranged in a direction perpendicular to the principal surface of the substrate and a oxidant flow path / electrode also serving as an oxidizer electrode are provided opposite to each other. A fuel cell comprising an electrolyte membrane that fills at least a gap between the fuel flow path electrode and the oxidant flow path electrode. The fuel is flowed in a direction perpendicular to the orientation direction of the carbon nanotubes in the fuel flow channel / electrode, and the oxidant is caused to flow in the direction perpendicular to the orientation direction of the carbon nanotubes in the oxidant flow passage / electrode. The fuel cell according to claim 1. 3. The fuel cell according to claim 1, wherein the density of the inner carbon nanotubes is lower than the density of the outer carbon nanotubes in the fuel channel electrode and the oxidant channel electrode made of carbon nanotubes. 3. The fuel cell according to claim 1, wherein the inside of the fuel flow channel electrode and the oxidant flow channel electrode made of carbon nanotubes is a cavity in which no carbon nanotubes exist. The tops of the fuel channel / electrode and oxidant channel / electrode made of carbon nanotubes are covered with an electrolyte membrane integral with the electrolyte membrane that fills the facing gap between the fuel channel / electrode and the oxidant channel / electrode. The fuel cell according to any one of claims 1 to 4, wherein:

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