WO2009157420A1 - Thin film fuel cell and method for manufacturing thin film fuel cell - Google Patents

Abstract

Disclosed is a thin film fuel cell (100) composed of Vycor glasses (1, 11); third conductive layers (2, 10) which are electron conducting layers respectively formed on a surface of the Vycor glasses (1, 11); primer layers (3, 9); a first conductive layer (4) and a second conductive layer (8) which are electron conducting layers; an anode electrode layer (5); an electrolyte layer (6); and a cathode electrode layer (7).  The primer layers (3, 9), the first conductive layer (4), the anode electrode layer (5), the electrolyte layer (6), the cathode electrode layer (7) and the second conductive layer (8) respectively have a structure wherein a cationic substance and an anionic substance are alternately laminated.  Consequently, there can be formed flat and smooth layers having no defect, which are in firm and close contact with each other by the electrostatic action between the layers.

Description

Thin film fuel cell and thin film fuel cell manufacturing method

The present disclosure relates to a thin film fuel cell and a thin film fuel cell manufacturing method.

Fuel cells can generate electricity with high efficiency in principle. Even if the fuel cell is small, sufficient power can be taken out. Therefore, the fuel cell is expected to be applied as a power source for mobile devices such as mobile phones and notebook computers. Also, by reducing the size of the fuel cell, it is possible to suppress the amount of expensive constituent materials such as noble metal materials used as electrode materials and perfluorocarbon sulfonic acids used as electrolyte layer materials. Therefore, the cost of the fuel cell can be suppressed.

As a specific means for improving the power generation efficiency and miniaturization of a fuel cell, a method of reducing the thickness of the electrolyte membrane and electrode membrane forming the fuel cell has been studied. By reducing the film thickness, the amount of the constituent material used can be suppressed. In addition, the thickness in the cell stacking direction can be suppressed. Furthermore, since the resistivity of the electrolyte membrane is reduced, the power generation efficiency can be improved. Currently, active research is being conducted to reduce the thickness of electrolyte membranes and electrode membranes (see, for example, Patent Document 1).
JP 2003-187825 A

However, it is very difficult to reduce the thickness of the electrolyte membrane and the electrode membrane while maintaining a uniform film thickness. In addition, the membrane is easily peeled off from the base substrate or other layers due to the thinning of the electrolyte membrane or the electrode membrane. Due to these factors, there has been a problem that the thicknesses of the electrolyte membrane and the electrode membrane have not reached a level that can be applied to a power supply for mobile devices.

The present disclosure has been made to solve the above-described problems, and is a thin film fuel cell in which an electrolyte membrane and an electrode membrane are thinned in a stable state, and a thin film in an electrolyte membrane and an electrode membrane in a stable state. An object of the present invention is to provide a method for manufacturing a thin film fuel cell.

According to the first aspect of the present disclosure, an electrolyte layer having a structure in which an anionic substance and a cationic substance are alternately laminated, and an anode electrode layer and a cathode electrode that are arranged to be opposed to each other with the electrolyte layer interposed therebetween The anode electrode layer and the cathode electrode layer, wherein at least one of the anode electrode layer and the cathode electrode layer has a structure in which anionic substances and cationic substances are alternately laminated. A thin film fuel cell comprising:

According to the second aspect of the present disclosure, the first electrode layer forming step of forming one electrode layer of the anode electrode layer or the cathode electrode layer by alternately laminating an anionic substance and a cationic substance; An electrolyte layer forming step of forming an electrolyte layer by alternately laminating an anionic substance and a cationic substance on one surface of the one electrode layer formed in the first electrode layer forming step; By alternately laminating an anionic substance and a cationic substance on the surface of the electrolyte layer formed in the electrolyte layer forming step on the opposite side of the surface in contact with the one electrode layer, the anode electrode layer or There is provided a method for producing a thin film fuel cell comprising a second electrode layer forming step of forming the other electrode layer of the cathode electrode layers.

1 is a schematic diagram showing a cross-sectional configuration of a thin film fuel cell 100. FIG. 3 is a flowchart showing a method for manufacturing the thin film fuel cell 100. 1 is a schematic diagram showing a cross-sectional configuration of a thin film fuel cell 100. FIG. It is a schematic diagram which shows the pre-processing process with respect to the Vycor glass 1. FIG. FIG. 5 is a schematic diagram showing a process for forming a third conductive layer 2. FIG. 4 is a schematic diagram showing a lamination process for laminating primer layer 3 to second conductive layer 8. It is a schematic diagram which shows the process of connecting the electrodes 21 and 22. FIG. It is a time-dependent change characteristic of an open circuit voltage. It is a time-dependent change characteristic of an open circuit voltage. It is an impedance measurement result.

Hereinafter, embodiments of a thin film fuel cell 100 and a thin film fuel cell manufacturing method embodying the present disclosure will be described with reference to the drawings. Note that these drawings are used to explain technical features that can be adopted by the present disclosure, and the contents described are merely illustrative examples, not a limitation.

First, the configuration of the thin film fuel cell 100 will be described with reference to FIG.

As shown in FIG. 1, the thin film fuel cell 100 includes Vycor glass 1 and 11. Third conductive layers 2 and 10, which are electron conductive layers, are formed on the surfaces of Vycor glass 1 and 11, respectively. Primer layers 3 and 9 are provided. A first conductive layer 4 and a second conductive layer 8 which are electron conductive layers are provided. An anode electrode layer 5, an electrolyte layer 6, and a cathode electrode layer 7 are provided. Of the third conductive layer 2 formed on the surface of the Vycor glass 1, the primer layer 3 is laminated on the side surface opposite to the surface in contact with the Vycor glass 1. The first conductive layer 4 is laminated on the side of the primer layer 3 opposite to the side in contact with the third conductive layer 2. An anode electrode layer 5 is stacked on the side surface of the first conductive layer 4 opposite to the surface in contact with the primer layer 3. An electrolyte layer 6 is laminated on the side of the anode electrode layer 5 opposite to the side in contact with the first conductive layer 4. A cathode electrode layer 7 is laminated on the side of the electrolyte layer 6 opposite to the surface in contact with the anode electrode layer 5. A second conductive layer 8 is laminated on the side of the cathode electrode layer 7 opposite to the side in contact with the electrolyte layer 6. A primer layer 9 is laminated on the side surface of the second conductive layer 8 opposite to the surface in contact with the cathode electrode layer 7. The side opposite to the surface in contact with the second conductive layer 8 in the primer layer 9 is in contact with the third conductive layer 10 in the state formed on the surface of the Vycor glass 11.

Further, electrodes 21 and 22 are connected to the first conductive layer 4 and the second conductive layer 8, respectively. A load 23 is connected to the opposite end of the electrode 21 on the side connected to the first conductive layer 4 and the opposite end of the electrode 22 on the side connected to the second conductive layer 8. When an electrochemical reaction occurs in the thin film fuel cell 100, electrons flow from the first conductive layer 4 toward the second conductive layer 8 through the electrodes 21 and 22. As a result, a current flows through the load 23.

Vycor glass 1 and 11 are layers ( primer layers 3 and 9, first conductive layer 4, anode electrode layer 5, electrolyte layer 6, cathode electrode layer 7) sandwiched between Vycor glass 1 and Vycor glass 11. , Support the second conductive layer 8, the third conductive layer 2 and 10). Vycor glass 1 and 11 is used as a base substrate for imparting strength to the main body of the thin film fuel cell 100. Vycor glass 1 and 11 has a porous property, and can transmit gas and liquid. Fuel (hydrogen gas or the like) or oxidant (oxygen gas or the like) supplied from the outside passes through the Vycor glass 1 and 11. The permeated fuel causes an electrochemical reaction in the anode electrode layer 5, the electrolyte layer 6, and the cathode electrode layer 7 (details will be described later).

In the present embodiment, a cationic substance is used as a material constituting each of the above-described layers ( primer layers 3 and 9, first conductive layer 4, anode electrode layer 5, electrolyte layer 6, cathode electrode layer 7, and second conductive layer 8). And anionic substances are used (details will be described later). The cationic substance has a positive charge. Anionic substances have a negative charge. By alternately laminating an anionic substance and a cationic substance, the above-described layers are stably formed on the Vycor glass 1 and 11. Each layer is laminated in a state where the Vycor glasses 1 and 11 are positively or negatively charged. As a result, each layer adheres firmly to the Vycor glass 1 and 11. As shown in FIG. 1, the first conductive layer 4, the anode electrode layer 5, the electrolyte layer 6, the cathode electrode layer 7, and the second conductive layer 8 are each composed of an anionic substance and a cationic substance. And may be alternately stacked. Accordingly, when another layer is stacked on one of the above-described layers, the charge polarity of each layer disposed in the contact portion can be easily reversed.

Vycor glasses 1 and 11 are usually produced by phase separation and etching of alkali borosilicate (Na ₂ OB ₂ O ₃ —SiO ₂ ) glass and have porosity. Vycor glass 1 and 11 are normally negatively charged in an aqueous solution. In addition to the Vycor glass 1 and 11, a well-known material having porosity and allowing gas or liquid to permeate can be used.

For example, a porous substrate prepared by mixing hydrophobic binder particles (fluorine resin powder) with carbon fine particles (carbon black) and hot pressing the same is also used in place of Vycor glass 1 and 11. be able to. Further, instead of Vycor glass 1 and 11 or a carbon-based porous substrate, porous stainless steel or a porous stainless steel tube can also be used. When a carbon-based porous substrate or a porous stainless material is used, since the substrate itself has high electronic conductivity, it is possible to omit the lamination of third conductive layers 2 and 10 described later. Note that the carbon-based porous substrate and the porous stainless steel material have a characteristic that they are easily charged in a water solution although they have a smaller charge than Vycor glass.

Third conductive layers 2 and 10 are formed on the surfaces of Vycor glass 1 and 11, respectively. The third conductive layer 2 collects the current generated in the anode electrode layer 5 by an electrochemical reaction and makes it easy to take it out. The third conductive layer 2 lowers an electron flow barrier when electrons are taken out to the outside. When an electrode for extracting electrons is connected to the third conductive layer 2, the third conductive layer 2 can efficiently transfer electrons to the electrode. The third conductive layer 10 is provided to facilitate supplying electrons from the outside to the cathode electrode layer 7. The third conductive layer 10 lowers the electron flow barrier when electrons are supplied from the outside. When an electrode for supplying electrons is connected to the third conductive layer 10, the third conductive layer 10 can efficiently transfer electrons to the cathode electrode layer 7.

As the material constituting the third conductive layers 2 and 10, conventionally known materials having electronic conductivity are used. For example, gold or Baytron (registered trademark) is used. In addition, as a method of laminating the third conductive layers 2 and 10, a conventionally known method capable of thinning and laminating the electron conductive material to be used is used. For example, a vacuum deposition method, a dip coating method, or a spin coating method is used.

In FIG. 1, the electrodes 21 and 22 are connected to the first conductive layer 4 and the second conductive layer 8. However, the present disclosure is not limited to this configuration. The third conductive layers 2 and 10 have electronic conductivity. For this reason, even when the electrodes 21 and 22 are connected to the third conductive layers 2 and 10, electrons flow efficiently and a current flows through the load 23.

The primer layers 3 and 9 are provided in order to smoothly laminate the first conductive layer 4 and the second conductive layer 8 laminated adjacent to each other with a uniform layer thickness. Vycor glass 1 and 11 has porosity. For this reason, many holes are formed on the surface. Primer layers 3 and 9 are filled into these holes. A smooth surface composed of the primer layers 3 and 9 is formed on the surfaces of the Vycor glass 1 and 11. As a result, the first conductive layer 4 and the second conductive layer 8 having smooth surfaces can be laminated. Since the thicknesses of the first conductive layer 4 and the second conductive layer 8 are uniform, the occurrence of a thin film defect is prevented.

As the material constituting the primer layers 3 and 9, a material capable of forming a smooth surface on the surface of the Vycor glass 1 and 11 is used. For example, polydiallyldimethylammonium chloride (PDDA) that is a cationic substance and polystyrene sulfonic acid (PSS) that is an anionic substance are used. A substance having a polarity opposite to the charged polarity of the layers adjacent to the primer layers 3 and 9 ( Vycor glass 1 and 11, the first conductive layer 4, the second conductive layer 8, etc.) is used. As a result, an electrostatic force acts between the adjacent layers and the primer layers 3 and 9 in the attracting direction. For this reason, the primer layers 3 and 9 firmly adhered to the adjacent layers are formed. In addition, a plurality of the above substances may be used, and an anionic substance and a cationic substance may be alternately stacked. By alternately laminating the cationic substance and the anionic substance, an electrostatic force acts in the attracting direction between the cationic substance and the anionic substance. For this reason, an anionic substance and a cationic substance adhere closely. Primer layers 3 and 9 having no defect are formed. As a method for laminating the primer layers 3 and 9, a conventionally well-known method capable of thinning and laminating materials used as the primer layers 3 and 9 is used. For example, a dip coating method or a spin coating method is used.

The first conductive layer 4 lowers the flow barrier when electrons flow from the adjacent anode electrode layer 5 to the electrode 21. The first conductive layer 4 collects electrons generated in the adjacent anode electrode layer 5 and makes it easy to take out to the outside through the electrode. In the configuration shown in FIG. 1, electrons generated in the anode electrode layer 5 and collected in the first conductive layer 4 flow to the load 23 through the electrode 21 attached to the first conductive layer 4.

As the material constituting the first conductive layer 4, a conventionally known material having electronic conductivity is used. For example, PDDA, which is a cationic substance, and Baytron, which is an anionic substance, are used. A substance having a polarity opposite to the charging polarity of the layers (primer layer 3, anode electrode layer 5, etc.) adjacent to the first conductive layer 4 is used. As a result, an electrostatic force acts between the two in the attracting direction. For this reason, the 1st conductive layer 4 closely_contact | adhered with the adjacent layer is formed. A plurality of these substances may be used, and a cationic substance and an anionic substance may be alternately laminated. By alternately laminating the anionic substance and the cationic substance, an electrostatic force acts in the attracting direction between the anionic substance and the cationic substance. For this reason, an anionic substance and a cationic substance adhere closely. The first conductive layer 4 having no defect is formed. As a method for laminating the first conductive layer 4, a conventionally well-known method capable of thinning and laminating a material used as the first conductive layer 4 is used. For example, a dip coating method or a spin coating method is used.

In the anode electrode layer 5, the fuel that has passed through the Vycor glass 1 is oxidized, and protons and electrons are generated. In the configuration shown in FIG. 1, the generated electrons are collected by the first conductive layer 4 and taken out through the electrode 21. The generated protons are transmitted through the electrolyte layer 6 to the cathode electrode layer 7.

As the material constituting the anode electrode layer 5, conventionally known materials used as electrode catalysts for fuel cells are used. For example, platinum or carbon-supported platinum in which platinum particles are supported on carbon black is used. Conventionally known materials are used as the cationic substance and the anionic substance. For example, PDDA is used as the cationic substance, and platinum colloid is used as the anionic substance. A substance having a polarity opposite to the charging polarity of a layer adjacent to the anode electrode layer 5 (the first conductive layer 4, the electrolyte layer 6 and the like) is used. As a result, an electrostatic force acts in the attracting direction between the adjacent layer and the anode electrode layer 5. For this reason, the anode electrode layer 5 firmly adhered to the adjacent layer is formed. In addition, when a plurality of these substances are used and the cationic substances and the anionic substances are alternately laminated, a force acts in the attracting direction between the anionic substances and the cationic substances. For this reason, an anionic substance and a cationic substance adhere closely. The anode electrode layer 5 having no defect is formed. As a method for laminating the anode electrode layer 5, a conventionally well-known method capable of thinning and laminating materials used as the anode electrode layer 5 is used. For example, a dip coating method or a spin coating method is used.

The electrolyte layer 6 transmits protons generated in the anode electrode layer 5 to the cathode electrode layer 7. The electrolyte layer 6 is isolated so that the fuel and the oxidant are not mixed. When a defect or the like exists in a part of the electrolyte layer 6, a short circuit phenomenon occurs between the anode electrode layer 5 and the cathode electrode layer 7, and the battery does not function. In the present embodiment, the electrolyte layer 6 has a laminated structure in which a cathodic substance and an anodic substance are laminated. Thereby, even when the electrolyte layer 6 is thinned, the occurrence of a defective portion is prevented. It is possible to prevent a short circuit from occurring in the thin film fuel cell 100.

As a material constituting the electrolyte layer 6, a cationic substance and an anionic substance are used. For example, polyallylamine hydrochloride (PAH) is used as the cationic substance. Nafion (registered trademark) is used as the anionic substance. By alternately laminating the cationic substance and the anionic substance, an electrostatic force acts in the attracting direction between the anionic substance and the cationic substance. For this reason, an anionic substance and a cationic substance adhere closely. The electrolyte layer 6 having no defect is formed. The cationic substance is preferably any one of a primary amine salt, a secondary amine salt, a tertiary amine salt, and a quaternary ammonium salt. These substances have a positively charged cationic property. For this reason, when it is set as a laminated structure, affinity with an anionic substance is strong. The anionic substance preferably has a sulfo group (SO ₃ H) or a phospho group (PO (OH) ₂ ). These groups have a negatively charged anionic property. For this reason, when it is set as a laminated structure, affinity with a cationic substance is strong. By using these substances, the electrolyte layer 6 which is more firmly adhered and has no defect portion is formed.

As a method of laminating a cationic substance and an anionic substance alternately, a conventionally well-known laminating method capable of thinning and laminating a material used as the electrolyte layer 6 is used. For example, a dip coating method or a spin coating method is used.

In the cathode electrode layer 7, water is generated from protons, an oxidant supplied from the outside, and electrons supplied from the electrode 22. Protons are generated in the anode electrode layer 5, pass through the electrolyte layer 6, and reach the vicinity of the cathode electrode layer 7. The generated water passes through the Vycor glass 11 and is discharged to the outside.

As the material constituting the cathode electrode layer 7, conventionally known materials used as electrode catalysts for fuel cells are used. For example, platinum or carbon-supported platinum in which platinum particles are supported on carbon black is used. Conventionally known materials are used as the cationic substance and the anionic substance. For example, PDDA is used as the cationic substance. Platinum colloid is used as the anionic substance. A substance having a polarity opposite to the charging polarity of a layer (electrolyte layer 6, second conductive layer 8, etc.) adjacent to the cathode electrode layer 7 is used. Thereby, an electrostatic force acts between the adjacent layers and the cathode electrode layer 7 in the attracting direction. For this reason, the anode electrode layer 5 firmly adhered to the adjacent layer is formed. In addition, when a plurality of these substances are used and the cationic substance and the anionic substance are alternately laminated, a force acts in the attracting direction between the cationic substance and the anionic substance. For this reason, the cationic substance and the anionic substance adhere firmly. A cathode electrode layer 7 having no defect is formed. As a method for laminating the cathode electrode layer 7, a conventionally well-known method capable of thinning and laminating a material used as the cathode electrode layer 7 is used. For example, a dip coating method or a spin coating method is used.

The second conductive layer 8 lowers the electron flow barrier when electrons flowing from the electrode 22 flow to the cathode electrode layer 7 adjacent to the second conductive layer 8. The second conductive layer 8 promotes the inflow of electrons to the cathode electrode layer 7. As a result, electrons flowing from the electrode 21 to the electrode 22 via the load 23 are supplied to the cathode electrode layer 7.

As the material constituting the second conductive layer 8, a conventionally known material having electronic conductivity is used. For example, PDDA, which is a cationic substance, and Baytron, which is an anionic substance, are used. A substance having a polarity opposite to the charging polarity of a layer (primer layer 9, cathode electrode layer 7, etc.) adjacent to the second conductive layer 8 is used. Thereby, an electrostatic force acts between the adjacent layers and the second conductive layer 8 in the attracting direction. For this reason, the 2nd conductive layer 8 closely_contact | adhered with the adjacent layer is formed. A plurality of these substances may be used, and a cationic substance and an anionic substance may be alternately laminated. By alternately laminating the anionic substance and the cationic substance, an electrostatic force acts in the attracting direction between the cationic substance and the anionic substance. For this reason, the cationic substance and the anionic substance adhere firmly. The second conductive layer 8 having no defect is formed. As a method for laminating the second conductive layer 8, a conventionally well-known method capable of thinning and laminating a material used as the second conductive layer 8 is used. For example, a dip coating method or a spin coating method is used.

Next, the driving principle of the thin film fuel cell 100 will be outlined with reference to FIG. The thin film fuel cell 100 causes an electrochemical reaction to generate an electromotive force. First, the side opposite to the side where the above-mentioned layers (primer layers 3 and 9, first conductive layer 4, anode electrode layer 5, electrolyte layer 6, cathode electrode layer 7, and second conductive layer 8) of Vycor glass 1 are laminated. Fuel (hydrogen gas, methanol, etc.) is supplied. Further, an oxidant (oxygen gas or the like) is supplied from the side opposite to the side on which the above-described layers of Vycor glass 11 are laminated.

The fuel supplied to the Vycor glass 1 penetrates the Vycor glass 1. Further, the third conductive layer 2, the primer layer 3, and the first conductive layer 4 penetrate. Then, it reaches the anode electrode layer 5. The fuel is oxidized at the anode electrode layer 5. Protons and electrons are generated.

The generated electrons are extracted to the outside through the first conductive layer 4 and the electrode 21 connected to the first conductive layer 4. The extracted electrons are supplied to a load 23 connected to the electrode 21. The electrons supplied to the load 23 flow into the electrode 22. Further, the generated protons pass through the electrolyte layer 6. Then, it reaches the cathode electrode layer 7.

Electrons flowing from the electrode 22 are supplied to the cathode electrode layer 7 via the second conductive layer 8. The oxidizing agent supplied to the Vycor glass 11 penetrates the third conductive layer 10, the primer layer 9, and the second conductive layer 8. Then, it reaches the cathode electrode layer 7. In the cathode electrode layer 7, protons, electrons, and an oxidizing agent react to generate water. The generated water is discharged to the outside through the second conductive layer 8, the primer layer 9, the third conductive layer 10, and the Vycor glass 11.

As described above, an electrochemical reaction is caused in the thin film fuel cell 100. Thus, the thin film fuel cell 100 operates as a “battery”. The thin film fuel cell 100 can pass a current through the load 23. In the configuration shown in FIG. 1, the voltage that can be extracted from the thin film fuel cell 100 is theoretically about 1.2V. Therefore, the configuration of the thin film fuel cell 100 is stacked in multiple stages and connected in series. This makes it possible to extract a large voltage.

When protons pass through the electrolyte layer 6, the smaller the diffusion resistance component, the lower the level of voltage drop caused by proton transmission. For this reason, a larger voltage can be taken out and the power generation efficiency is improved. The diffusion resistance component decreases as the thickness of the electrolyte layer 6 decreases. However, when the electrolyte layer 6 is thinned, there is a high possibility that a defective portion is partially generated. When a defect portion exists in the electrolyte layer 6, electrons generated in the anode electrode layer 5 reach the cathode electrode layer 7 directly through the electrolyte layer 6. For this reason, the electric current taken out decreases and the power generation efficiency decreases.

In the thin film fuel cell 100 of the present disclosure, the electrolyte layer 6 is formed by laminating a cationic substance and an anionic substance. As a result, it is possible to suppress the occurrence of a defective portion of the layer as compared with the conventional electrolyte layer forming method. The occurrence of a short circuit between the anode electrode layer 5 and the cathode electrode layer 7 can be suppressed. In addition, the layer can be thinned. This reduces the resistance component when protons pass through the electrolyte layer 6. It is possible to suppress the voltage drop and improve the power generation efficiency.

Also, the cationic substance and the anionic substance are laminated alternately. The cationic substance and the anionic substance are firmly adhered to each other by the electrostatic force in the attracting direction generated between the cationic substance and the anionic substance. An electrolyte layer 6 that is difficult to peel is formed. The electrolyte layer 6 having excellent strength is formed even when the layer thickness is reduced.

In the present disclosure, each layer (primer layers 3 and 9, first conductive layer 4, anode electrode layer 5, cathode electrode layer 7, second conductive layer 8) is formed by laminating a cationic substance and an anionic substance. Is done. As a result, like the electrolyte layer 6, it is possible to suppress generation of a defect portion of the layer and reduce the entire layer thickness. For this reason, the thickness of the entire thin film fuel cell 100 in the stacking direction is suppressed. The thin film fuel cell 100 can be downsized. Furthermore, an electrostatic force in the attracting direction is generated between the cationic substance and the anionic substance. Thereby, each layer (primer layers 3 and 9, first conductive layer 4, anode electrode layer 5, cathode electrode layer 7, second conductive layer 8) having excellent strength is formed.

A method of manufacturing the thin film fuel cell 100 will be described with reference to FIG. In the following embodiment, it is assumed that the thin film fuel cell 100 is manufactured using the negatively charged Vycor glass 1 and 11. However, the charging characteristics of the Vycor glass 1 are not limited to such a case. The thin film fuel cell 100 may be produced using the positively charged Vycor glass 1. In the following description, each layer (third conductive layer 2, primer layer 3, first conductive layer 4, anode electrode layer 5, electrolyte layer 6, cathode electrode layer 7, second conductive layer of Vycor glass 1 in FIG. The side on which the layer 8, the primer layer 9, and the third conductive layer 10) are formed is defined as the upper side.

As shown in FIG. 2, in the process of manufacturing the thin film fuel cell 100, first, the third conductive layer 2 is formed on the upper side of the Vycor glass 1 (S11). Hereinafter, the process in which the third conductive layer 2 is formed on the surface of the Vycor glass 1 is referred to as a “third conductive layer forming process”.

Next, the primer layer 3 is laminated on the upper side of the third conductive layer 2 formed on the upper side of the Vycor glass 1 in the third conductive layer forming step (S13, S15). As the material constituting the primer layer 3, two types of a cationic substance (hereinafter referred to as “primer cation”) and an anionic substance (hereinafter referred to as “primer anion”) are used. The primer layers 3 are formed by alternately laminating the respective substances. Hereinafter, the step of forming the primer layer 3 on the third conductive layer 2 is referred to as “primer layer forming step”.

In the primer layer forming step, first, a primer cation having a polarity opposite to the charged polarity (minus) of the Vycor glass 1 is laminated on the third conductive layer 2 (S13). An electrostatic force acts between the Vycor glass 1 and the primer cation in the attracting direction. For this reason, the Vycor glass 1 and the primer cation adhere firmly. Next, a primer anion having a polarity opposite to the polarity (plus) of the primer cation is stacked on the upper side of the stacked primer cations (S15). An electrostatic force acts between the primer cation and the primer anion in the attracting direction. For this reason, the primer cation and the primer anion are firmly adhered.

Next, it is determined whether or not the primer cations and primer anions stacked in S13 and S15 have been stacked for a predetermined number of layers (S17). When the predetermined number of layers are not stacked (S17: NO), the process returns to S13. A primer cation is laminated on the upper side of the primer anion (S13). An electrostatic force acts between the primer anion and the primer cation in the attracting direction. For this reason, the primer anion and the primer cation are firmly adhered. Then, the above process is repeated. On the other hand, when the primer cation and the primer anion are stacked for a predetermined number of layers (S17: YES), the primer layer forming step is ended. Subsequently, the formation process of the 1st conductive layer 4 is performed.

After completion of the primer layer forming step, the first conductive layer 4 is laminated on the upper side of the primer layer 3 formed in the primer layer forming step (S19, S21). As the material constituting the first conductive layer 4, two kinds of materials, that is, a cationic substance (hereinafter referred to as “first conductive cation”) and an anionic substance (hereinafter referred to as “first conductive anion”) are used. . The first conductive layer 4 is formed by alternately laminating each material. Hereinafter, the process in which the first conductive layer 4 is formed on the primer layer 3 is referred to as a “first conductive layer forming process”.

In the first conductive layer forming step, first, a first polarity having a polarity opposite to the charging polarity of the uppermost layer of the primer layer 3 (primer anion is laminated on the uppermost layer. The charging polarity is negative. See S15). Conductive cations are stacked on the upper side of the primer layer 3 (S19). An electrostatic force acts between the first conductive cation and the primer layer 3 in the attracting direction. For this reason, the first conductive cation and the primer layer 3 are firmly adhered. Next, a first conductive anion having a polarity opposite to that of the stacked first conductive cation is stacked on the upper side of the first conductive cation (S21). An electrostatic force acts between the first conductive cation and the first conductive anion in the attracting direction. For this reason, the first conductive cation and the first conductive anion are firmly adhered.

Next, it is determined whether or not the first conductive cation and the first conductive anion laminated in S19 and S21 are laminated for a predetermined number of layers (S23). If the predetermined number of layers are not stacked (S23: NO), the process returns to S19. A first conductive cation is stacked on the upper side of the first conductive anion (S19). An electrostatic force acts between the first conductive anion and the first conductive cation in the attracting direction. For this reason, the first conductive anion and the first conductive cation are firmly adhered. Then, the above process is repeated. On the other hand, when the first conductive cation and the first conductive anion are stacked for a predetermined number of layers (S23: YES), the first conductive layer forming step is ended. Subsequently, the formation process of the anode electrode layer 5 is performed.

After completion of the first conductive layer forming step, the anode electrode layer 5 is laminated on the upper side of the first conductive layer 4 formed in the first conductive layer forming step (S25, S27). As a material constituting the anode electrode layer 5, two kinds of materials, a cationic substance (hereinafter referred to as “anode cation”) and an anionic substance (hereinafter referred to as “anode anion”) are used. The anode electrode layer 5 is formed by alternately laminating each material. Hereinafter, the process in which the anode electrode layer 5 is formed on the first conductive layer 4 is referred to as an “anode electrode layer forming process”.

In the anode electrode layer forming step, first, the polarity opposite to the charged polarity of the uppermost layer of the first conductive layer 4 (the first conductive anion is laminated on the uppermost layer. The charged polarity is negative. See S21). The anode cation having the same is laminated on the upper side of the first conductive layer 4 (S25). An electrostatic force acts between the anode cation and the first conductive layer 4 in the attracting direction. For this reason, the anode cation and the first conductive layer 4 are firmly adhered. Next, an anode anion having a polarity opposite to that of the laminated anode cation is laminated on the anode cation (S27). An electrostatic force acts between the anode cation and the anode anion in the attracting direction. For this reason, the anode cation and the anode anion are firmly adhered.

Next, it is determined whether or not the anode cations and anode anions stacked in S25 and S27 have been stacked for a predetermined number of layers (S29). When the predetermined number of layers are not stacked (S29: NO), the process returns to S25. An anode cation is stacked on the upper side of the anode anion (S25). An electrostatic force acts between the anode anion and the anode cation in the attracting direction. For this reason, the anode anion and the anode cation are firmly adhered. Then, the above process is repeated. On the other hand, when the anode cation and the anode anion are stacked for a predetermined number of layers (S29: YES), the anode electrode layer forming step is ended. Subsequently, the formation process of the electrolyte layer 6 is performed.

After completion of the anode electrode layer forming step, the electrolyte layer 6 is laminated on the upper side of the anode electrode layer 5 formed in the anode electrode layer forming step (S31, S33). As the material constituting the electrolyte layer 6, two kinds of materials, that is, a cationic substance (hereinafter referred to as “electrolyte cation”) and an anionic substance (hereinafter referred to as “electrolyte anion”) are used. Each material is laminated alternately. Thereby, the electrolyte layer 6 is formed. Hereinafter, the process in which the electrolyte layer 6 is formed on the anode electrode layer 5 is referred to as “electrolyte layer formation process”.

In the electrolyte layer forming step, first, an electrolyte cation having a polarity opposite to the charging polarity of the uppermost layer of the anode electrode layer 5 (the anode anion is laminated on the uppermost layer. The charging polarity is negative. See S27). Then, it is laminated on the upper side of the anode electrode layer 5 (S31). An electrostatic force acts between the electrolyte cation and the anode electrode layer 5 in the attracting direction. For this reason, the electrolyte cation and the anode electrode layer 5 are firmly adhered. Next, an electrolyte anion having a polarity opposite to that of the stacked electrolyte cation is stacked on the upper side of the electrolyte cation (S33). An electrostatic force acts between the electrolyte cation and the electrolyte anion in the attracting direction. For this reason, the electrolyte cation and the electrolyte anion are firmly adhered.

Next, it is determined whether or not the electrolyte cation and the electrolyte anion laminated in S31 and S33 are laminated for a predetermined number of layers (S35). When the predetermined number of layers are not stacked (S35: NO), the process returns to S31. An electrolyte cation is stacked on the upper side of the electrolyte anion (S31). An electrostatic force acts in the pulling direction between the electrolyte anion and the electrolyte cation. For this reason, the electrolyte anion and the electrolyte cation are firmly adhered. Then, the above process is repeated. On the other hand, when the electrolyte cation and the electrolyte anion are stacked by the predetermined number of layers (S35: YES), the electrolyte layer forming step is ended. Next, a step of forming the cathode electrode layer 7 is performed.

After completion of the electrolyte layer forming step, the cathode electrode layer 7 is laminated on the upper side of the electrolyte layer 6 formed in the electrolyte layer forming step (S37, S39). As the material constituting the cathode electrode layer 7, two kinds of materials, ie, a cationic substance (hereinafter referred to as “cathode cation”) and an anionic substance (hereinafter referred to as “cathode anion”) are used. Each material is laminated alternately. Thereby, the cathode electrode layer 7 is formed. Hereinafter, the step of forming the cathode electrode layer 7 on the electrolyte layer 6 is referred to as “cathode electrode layer forming step”.

In the cathode electrode layer forming step, first, a cathode cation having a polarity opposite to the charged polarity of the uppermost layer of the electrolyte layer 6 (electrolyte anion is laminated on the uppermost layer. The charged polarity is negative. See S33). Then, it is laminated on the upper side of the electrolyte layer 6 (S37). An electrostatic force acts between the cathode cation and the electrolyte layer 6 in the attracting direction. For this reason, the anode cation and the electrolyte layer 6 are firmly adhered. Next, a cathode anion having a polarity opposite to that of the stacked cathode cation is stacked on the upper side of the cathode cation (S39). An electrostatic force acts between the cathode cation and the cathode anion in the attracting direction. For this reason, the cathode cation and the cathode anion are firmly adhered.

Next, it is determined whether or not the cathode cation and the cathode anion laminated in S37 and S39 are laminated for a predetermined number of layers (S41). When the predetermined number of layers are not stacked (S41: NO), the process returns to S37. A cathode cation is stacked on the upper side of the cathode anion (S37). An electrostatic force acts between the cathode anion and the cathode cation in the attracting direction. For this reason, the cathode anion and the cathode cation are firmly adhered. Then, the above process is repeated. On the other hand, when the cathode cation and the cathode anion are stacked for a predetermined number of layers (S41: YES), the cathode electrode layer forming step is ended. Subsequently, the formation process of the 2nd conductive layer 8 is performed.

After completion of the cathode electrode layer forming step, the second conductive layer 8 is laminated on the upper side of the cathode electrode layer 7 formed in the cathode electrode layer forming step (S43, S45). As a material constituting the second conductive layer 8, two kinds of materials, a cationic substance (hereinafter referred to as “second conductive cation”) and an anionic substance (hereinafter referred to as “second conductive anion”) are used. . Each material is laminated alternately. Thereby, the second conductive layer 8 is formed. Hereinafter, the process in which the second conductive layer 8 is formed on the cathode electrode layer 7 is referred to as a “second conductive layer forming process”.

In the second conductive layer forming step, first, the uppermost layer of the cathode electrode layer 7 is charged with the opposite polarity to the charged polarity (the cathode anion is laminated on the uppermost layer. The charged polarity is negative, see S39). Biconductive cations are stacked on the upper side of the cathode electrode layer 7 (S43). An electrostatic force acts between the second conductive cation and the cathode electrode layer 7 in the attracting direction. For this reason, the second conductive cation and the cathode electrode layer 7 are firmly adhered.

Next, a second conductive anion having a polarity opposite to that of the stacked second conductive cation is stacked on the upper side of the second conductive cation (S45). An electrostatic force acts between the second conductive cation and the second conductive anion in the attracting direction. For this reason, the second conductive cation and the second conductive anion are firmly adhered.

Next, it is determined whether or not the second conductive cation and the second conductive anion stacked in S43 and S45 are stacked for a predetermined number of layers (S47). When the predetermined number of layers are not stacked (S47: NO), the process returns to S43. A second conductive cation is stacked on the upper side of the second conductive anion (S43). An electrostatic force acts between the second conducting anion and the second conducting cation in the attracting direction. For this reason, the second conductive anion and the second conductive cation are firmly adhered. Then, the above process is repeated. On the other hand, when the second conductive cation and the second conductive anion are stacked for a predetermined number of layers (S47: YES), the second conductive layer forming step is ended.

After the end of the second conductive layer forming step (S47: YES), the Vycor glass 11 with the third conductive layer 10 and the primer layer 9 formed on the surface is pasted on the formed second conductive layer 8 ( S49). The Vycor glass 11 is stuck in the direction in which the second conductive layer 8 and the primer layer 9 are in contact with each other. Then, the thin film fuel cell manufacturing process is completed.

Through the steps described above, the thin film fuel cell 100 having the thin electrolyte layer 6 without any defect is manufactured. In this manufacturing method, the electrolyte layer 6 is formed by laminating a cationic substance and an anionic substance. This prevents the occurrence of a defect in the electrolyte layer 6. Therefore, a voltage drop due to a short circuit between the anode electrode layer 5 and the cathode electrode layer 7 is suppressed. It becomes possible to manufacture the thin film fuel cell 100 with high power generation efficiency. The cationic substance and the anionic substance are firmly adhered to each other by the electrostatic force acting between the cationic substance and the anionic substance. Therefore, it is possible to prevent the electrolyte layer 6 from peeling off. A stable and durable thin film fuel cell 100 is manufactured. By making the electrolyte layer 6 thin, the amount of the material constituting the electrolyte layer 6 is suppressed. The cost of the thin film fuel cell 100 can be reduced. By making the electrolyte layer 6 thinner, the thickness of the thin film fuel cell 100 in the stacking direction becomes smaller. The thin film fuel cell 100 can be downsized. Specifically, the thickness of the thin film fuel cell 100 can be set to 100 μm or less.

The primer layer 3, the first conductive layer 4, the anode electrode layer 5, the cathode electrode layer 7, the second conductive layer 8, and the primer layer 9 are formed by laminating the cationic substance and the anionic substance. As a result, even when these layers are thinned, the occurrence of a defect portion is prevented. A short circuit between layers is prevented. The fuel cell can be miniaturized. The cationic substance and the anionic substance are firmly adhered by the electrostatic force acting between the cationic substance and the anionic substance. Therefore, it is possible to prevent the peeling of each layer. A stable and durable thin film fuel cell 100 is manufactured. The amount of material used for each layer is reduced. As a result, the cost of the thin film fuel cell 100 can be reduced.

In addition, this indication is not limited to the said embodiment, A various change is possible.

The thin film fuel cell 100 has a configuration including the first conductive layer 4 and the second conductive layer 8. The present disclosure is not limited to this configuration, and may include the first conductive layer 4 and the second conductive layer 8. Even if the first conductive layer 4 and the second conductive layer 8 are not included, the thin film fuel cell 100 is driven on the same principle as described above to generate an electromotive force. In this configuration, the electrodes 21 and 22 are connected to the other conductive layers (third conductive layers 2 and 10), the anode electrode layer 5, and the cathode electrode layer 7. As a result, the electromotive force generated in the thin film fuel cell 100 can be taken out.

The thin film fuel cell 100 had a configuration including the primer layers 3 and 9. The present disclosure is not limited to this configuration, and may be a configuration that does not include the primer layers 3 and 9. Even if the primer layers 3 and 9 are not included, the thin film fuel cell 100 is driven on the same principle as described above to generate an electromotive force.

As the material constituting the primer layers 3 and 9 in the thin film fuel cell 100, a material having electron conductivity is used. By connecting the electrodes 21 and 22 to the primer layers 3 and 9, the electromotive force generated in the thin film fuel cell 100 can be taken out to the outside.

The thin film fuel cell 100 has a configuration including the third conductive layers 2 and 10. The present disclosure is not limited to this configuration, and may include the third conductive layers 2 and 10. Even if the third conductive layers 2 and 10 are not included, the thin film fuel cell 100 is driven on the same principle as described above to generate an electromotive force.

The thin film fuel cell 100 had a configuration including Vycor glass 1 and 11. The present disclosure is not limited to this configuration, and may be a configuration that does not include Vycor glass 1 and 11. Even in a configuration that does not include the Vycor glass 1 and 11, the thin film fuel cell 100 is driven on the same principle as described above to generate an electromotive force.

In the thin film fuel cell manufacturing method, a primer layer 3, a first conductive layer 4, an anode electrode layer 5, an electrolyte layer 6, a cathode electrode layer 7, a second conductive layer 8, a primer layer 9, and Vycor are disposed above the Vycor glass 1. Glasses 11 were sequentially laminated. The present disclosure is not limited to this manufacturing method. On the upper side of the Vycor glass 11, the primer layer 9, the second conductive layer 8, the cathode electrode layer 7, the electrolyte layer 6, the anode electrode layer 5, the first conductive layer 4, the primer layer 3, and the Vycor glass 1 are sequentially laminated. It doesn't matter how.

The thin film fuel cell manufacturing method of the present disclosure may be a manufacturing method in which the third conductive layer forming step, the primer layer forming step, the first conductive layer forming step, and the second conductive layer forming step are omitted. A method in which the third conductive layers 2 and 10, the primer layer 3, the first conductive layer 4, and the second conductive layer 8 are not formed may be used.

In the thin film fuel cell manufacturing method, in each step (primer layer forming step, first conductive layer forming step, anode electrode layer forming step, electrolyte layer forming step, cathode electrode layer forming step, and second conductive layer forming step) The active substance was first laminated, and then the anionic substance was laminated. However, the present disclosure is not limited to this method. When the charging polarity of the underlayer is positive, an anionic substance having a negative polarity may be laminated first.

In the thin film fuel cell manufacturing method, an anionic substance is laminated in each step (primer layer forming step, first conductive layer forming step, anode electrode layer forming step, cathode electrode layer forming step, and second conductive layer forming step). After that, it was determined whether or not a predetermined number of layers were stacked. However, the present disclosure is not limited to this determination method. Similarly, it may be determined whether or not a predetermined number of layers have been stacked after the cationic substances are stacked.

In the thin film fuel cell manufacturing method, in each step (primer layer forming step, first conductive layer forming step, anode electrode layer forming step, cathode electrode layer forming step, and second conductive layer forming step), a cationic substance and an anionic property Each layer was formed by alternately laminating substances. However, the present disclosure is not limited to this lamination method. Therefore, each layer may be formed by laminating a single substance.
<Example>

Examples of the present disclosure will be described. Hereinafter, “1. Configuration of the thin film fuel cell 100”, “2. About used materials”, “3. Outline of manufacturing procedure of the thin film fuel cell 100”, “4.
1. Configuration of thin film fuel cell 100

The structure of the prepared thin film fuel cell 100 will be described with reference to FIG. The upper side in FIG. 3 is defined as the upper side of the thin film fuel cell 100.

As shown in FIG. 3, in this embodiment, the third conductive layer 2, the primer layer 3, the anode electrode layer 5, the electrolyte layer 6, the cathode electrode layer 7, and the second conductive layer 8 are sequentially formed on the Vycor glass 1. Laminated. The first conductive layer 4, the primer layer 9, the third conductive layer 10, and the Vycor glass 11 are not laminated. Electrodes 21 and 22 were connected to the primer layer 3 and the second conductive layer 8, respectively.

Fuel (hydrogen or methanol) is supplied from the lower side of the Vycor glass 1. An electrochemical reaction is caused in the anode electrode layer 5 and the cathode electrode layer 7. As a result, current is extracted from the electrode 21 and the electrode 22. The oxidant (oxygen) necessary for the electrochemical reaction is not forcibly supplied into the thin film fuel cell 100. It was naturally supplied by bringing air into contact with the upper side of the second conductive layer 8.
2. About the materials used

As the Vycor glass 1, “7930” manufactured by USA Corning was used. Vycor glass 1 was cut into a size of 2 cm × 3 cm and used. The primer layer 3 was formed by laminating primer cations and primer anions. The anode electrode layer 5 was formed by laminating anode cations and anode anions. The electrolyte layer 6 was formed by stacking electrolyte cations and electrolyte anions on each other. The cathode electrode layer 7 was formed by laminating a cathode cation and a cathode anion. The second conductive layer 8 was formed by alternately laminating the second conductive cation and the second conductive anion. The primer cation and primer anion were laminated in four layers. Four layers of anode cations and anode anions were laminated. 20 layers of electrolyte cations and electrolyte anions were laminated. The cathode cation and cathode anion were laminated in four layers. The second conductive cation and the second conductive anion were laminated in four layers.

PDDA was used as a primer cation constituting the primer layer 3. PSS was used as a primer anion constituting the primer layer 3. PDDA was used as an anode cation constituting the anode electrode layer 5. Platinum colloid was used as the anode anion constituting the anode electrode layer 5. PAH was used as the electrolyte cation constituting the electrolyte layer 6. Nafion was used as the electrolyte anion constituting the electrolyte layer 6. PDDA was used as a cathode cation constituting the cathode electrode layer 7. A platinum colloid was used as a cathode anion constituting the cathode electrode layer 7. PDDA was used as the second conductive cation constituting the second conductive layer 8. Baytron was used as the second conductive anion constituting the second conductive layer 8. The above contents are summarized in Table 1.

Aldrich products were used as PDDA. A 0.5 mol / l aqueous sodium chloride solution was added to PDDA. The concentration was adjusted so that the content of PDDA was 1 mg / ml. Aldrich products were used as PSS. Similar to PDDA, 0.5 mol / l aqueous sodium chloride solution was added to PDDA. The concentration of PDDA was adjusted and used so that the content of PSS was 1 mg / ml.

1 part by weight of hexachloroplatinic (IV) acid (hexahydrate) aqueous solution (referred to as “reagent A”), methanol (referred to as “reagent B”), 0.04 mol / l trisodium citrate aqueous solution (“reagent” C ") was used. After mixing reagent A (100 μl), reagent B (9000 μl), and reagent C (200 μl), ultraviolet light (center wavelength: 365 nm, intensity: 10 mW / cm ² ) was irradiated for 10 minutes. A photoreduction method was generated by ultraviolet irradiation, and a colloidal solution in which platinum nanoparticles were dispersed was obtained. The resulting colloidal solution was used as a platinum colloid.

Aldrich product was used as PAH. A 0.5 mol / l aqueous sodium chloride solution was added to the PAH. The concentration was adjusted so that the PAH content was 1 mg / ml. Aldrich product Nafion was used. A 90% by volume aqueous methanol solution was added, and the concentration was adjusted so that the Nafion content was 1 mg / ml.

TA Chemical Co., Ltd. product Baytron was used. A 0.5 mol / l aqueous sodium chloride solution was added, and the concentration was adjusted and used so that the content of Baytron was 1 mg / ml.
3. Outline of production procedure of thin film fuel cell 100

An outline of the production procedure of the thin film fuel cell 100 will be described with reference to FIGS.

Referring to FIG. 4, the pretreatment process for Vycor glass 1 will be described. As shown in FIG. 4, first, a masking tape 31 (a heat release sheet “Riva Alpha” manufactured by Nitto Denko Corporation) was attached to a part of Vycor glass 1. The masking tape 31 is affixed to prevent the electrode 22 from being short-circuited with the electrode 21 when the electrode 22 is connected. By applying the masking tape 31, the third conductive layer 2 was not laminated on the applied part.

The third conductive layer forming step will be described with reference to FIG. As shown in FIG. 5, in the third conductive layer forming step, the third conductive layer 2 was formed on the Vycor glass 1 with a masking tape 31 attached to a part thereof. A sputtering method was adopted as a lamination method. A third conductive layer 2 made of gold was formed on the surface of Vycor glass 1.

Next, the masking tape 31 attached in the pretreatment process was peeled off. Next, in order to connect the electrode 21 to the formed third conductive layer 2, a masking tape 32 (Nitto Denko Thermal Release Sheet “Riva Alpha”) was attached to a part of the third conductive layer 2. By affixing the masking tape 32, other layers were prevented from being laminated on the affixed portion.

With reference to FIG. 6, the lamination process of laminating the primer layer 3 to the second conductive layer 8 will be described. As shown in FIG. 6, in the laminating step, the primer layer 3, the anode electrode layer 5, the electrolyte layer 6, the cathode electrode layer 7, and the second conductive layer 8 are sequentially placed above the Vycor glass 1 and the third conductive layer 2. Laminated.

As a method of laminating the primer layer 3, the anode electrode layer 5, the electrolyte layer 6, the cathode electrode layer 7, and the second conductive layer 8, a spin coating method was used. Vycor glass 1 with the third conductive layer 2 laminated thereon was set on a spin coater. The rotation speed was set to 2000 to 3000 rpm. In the state where the Vycor glass 1 was rotated, the above-mentioned preparation reagents were sequentially dropped from above. Thereby, each layer was formed.

Preparation reagent was added dropwise one by one. Immediately after the dropping, several drops of ion-exchanged water were dropped. This removed excess reagent. Immediately after the ion-exchanged water was dropped, one drop of the reagent constituting the next layer was dropped. This process was repeated for the desired number of layers. As a result, the primer layer 3, the anode electrode layer 5, the electrolyte layer 6, the cathode electrode layer 7, and the second conductive layer 8 were laminated. The primer layer 3 was formed by laminating four layers of first conductive cations (PDDA) and first conductive anions (PSS) alternately. The anode electrode layer 5 was formed by alternately stacking four layers of anode cations (PDDA) and anode anions (platinum colloids). The electrolyte layer 6 was formed by alternately stacking 20 layers of electrolyte cations (PAH) and electrolyte anions (Nafion). The cathode electrode layer 7 was formed by alternately stacking four layers of cathode cations (PDDA) and cathode anions (platinum colloids). The second conductive layer 8 was formed by alternately stacking four layers of second conductive cations (PDDA) and second conductive anions (Baytron).

As described above, the combination of the anionic substance and the cationic substance, the concentration of the anionic substance and the cationic substance in the preparation reagent, the concentration of sodium chloride, and the like were determined. As a result, the thickness of each layer composed of a cationic substance and an anionic substance is about one molecule of the constituent substance (PDDA, PSS, PAH: about 1 nm, Nafion: about 5 to 10 nm), transparent Layer was formed.

The thickness of each layer was measured by a quartz crystal microbalance (QCM) (product name: TYPE 7B) manufactured by USAI. QCM uses the piezoelectric effect of a crystal resonator to convert a change in resonance frequency into a weight. QCM can measure a change in weight on the order of nanograms in a gas phase and a liquid phase. The measurement is performed as follows, for example. First, the surface of the QCM substrate (gold is deposited as an electrode) is cleaned, and after drying, the frequency is measured. This value becomes the reference frequency (F0). Next, each layer is formed on the QCM substrate by the film forming method described above. After forming the layer, it is thoroughly washed with water and then dried with nitrogen gas or the like. The frequency is then measured. From the difference (ΔF) from the reference frequency, the weight of the layers stacked per unit area is obtained with nanogram order accuracy. The thickness per layer (d) (unit: nm) can be obtained from the following equation from the frequency change (ΔF) of the QCM and the density (ρ) of the polymer film (unit: g / cm ³ ).
d = (f × ΔF) / ρ
f is a constant determined by the device and the electrode area.

From the density of Nafion (1.64 g / cm ³ ), it was found that the average thickness per layer of the Nafion layer was 5 nm when a pH 8 PAH solution was used. The average thickness per layer of the Nafion layer was 14 nm when a pH 10 PAH solution was used. It was found that the thickness of the Nafion layer to be laminated greatly depends on the pH of the PAH solution. Similar measurements were made for layers where other materials (PDDA, PSS, PAH) were used. It was confirmed that the thickness of the layer was about one molecule of the constituent material.

With reference to FIG. 7, the connection process of the electrodes 21 and 22 is demonstrated. In this step, as shown in FIG. 7, the masking tape 32 in a state of being stuck on the third conductive layer 2 was peeled off. A copper wire was fixed to the third conductive layer 2 exposed by peeling off the masking tape 32 with a silver paste. The fixed wire becomes the electrode 21. Moreover, the copper wire was fixed to the part equivalent to the part which affixed the masking tape 31 (refer FIG. 3) in the pre-processing process among the uppermost 2nd conductive layers 8 with the silver paste. The fixed wire becomes the electrode 22. Through the above steps, the thin film fuel cell 100 was produced. The thickness of the thin film fuel cell 100 except the Vycor glass 1 in the stacking direction was about 200 to 360 nm. Note that the thickness of the Vycor glass 1 is several tens of μm.

The thickness was estimated as follows. The thickness per layer when the PDDA was laminated was 1 nm, which is about the size of one PDDA molecule. The thickness per layer when PSS was laminated was set to 1 nm, which is about the size of one PSS molecule. The thickness per layer when platinum colloid was laminated was 5 to 10 nm. The thickness per layer when PAH was laminated was set to 1 nm which is about the size of PAH1 molecule. When Nafion was stacked, the thickness per layer was set to 5 to 10 nm, which was about one Nafion molecule. The thickness per layer when Baytron was laminated was 5 to 10 nm.

And the thickness of each layer was multiplied by the number of layers. The thickness of the primer layer 3 was (1 nm (PDDA) +1 nm (PSS)) × 4 (layer) = 8 nm. The thickness of the anode conductive layer 5 was (1 nm (PDDA) +5 to 10 nm (platinum colloid)) × 4 (layer) = 24 to 44 nm. The thickness of the electrolyte layer 6 was (1 nm (PAH) +5 to 10 nm (Nafion)) × 20 (layer) = 120 to 220 nm. The thickness of the cathode electrode layer 7 was (1 nm (PDDA) +5 to 10 nm (platinum colloid)) × 4 (layer) = 24 nm to 44 nm. The thickness of the second conductive layer 8 was (1 nm (PDDA) +5 to 10 nm (Baytron)) × 4 (layer) = 24 to 44 nm. The total of these was 200 to 360 nm.

Thus, it has become clear that the thin film fuel cell 100 of the order of several hundred nm can be produced in this embodiment. Since the thickness of the conventional fuel cell in the stacking direction is several hundred μm, it has become clear that it is possible to produce a fuel cell that is much thinner than the conventional one.

Note that the number of layers described above is an example, and the present disclosure is not limited to this number of layers. For example, it is good also as a structure which does not laminate | stack repeatedly each layer 2 or more. In this case, the thickness of the thin film fuel cell 100 in the stacking direction is about 26 nm. Moreover, it is good also as a structure which laminated | stacked each layer 100 times the above-mentioned lamination | stacking number. In this case, the thickness of the thin film fuel cell 100 in the stacking direction is about 36 μm. Accordingly, it has been clarified that the thin film fuel cell 100 having a thickness of at least about 100 μm or less can be produced even when the Vycor glass 1 (several tens of μm) is used.
4). Evaluation method and conditions

The evaluation method of the prepared thin film fuel cell 100 will be described. An open circuit voltage measurement was performed on the prepared thin film fuel cell 100. For the prepared thin film fuel cell 100, the voltage between the electrode 21 and the electrode 22 in a state where no load was applied was measured. In addition, impedance measurement was performed. The impedance between the electrode 21 and the electrode 22 was measured for the prepared thin film fuel cell 100. The presence / absence of a short circuit and battery characteristics were evaluated.

As a measuring instrument for measuring an open circuit voltage, a potentron galvanostat “1287” manufactured by Solartron was used. The open circuit voltage was measured under conditions where pure hydrogen was supplied as fuel and methanol was supplied. The battery characteristics of the thin film fuel cell 100 were evaluated from the measurement results of the battery voltage. When pure hydrogen was supplied as the fuel, pure hydrogen was supplied from the lower side of the Vycor glass 1 so that the flow rate was 10 ml / min. When methanol was supplied as a fuel, a 20% by volume methanol aqueous solution was supplied to the lower side of the Vycor glass 1 using a syringe.

The potentio galvanostat “1287” manufactured by Solartron was used as a measuring instrument for measuring impedance. A square wave having an amplitude of 1000 mV and a frequency of 1 to 100 kHz was applied between the electrode 21 and the electrode 22. Impedance was measured when a square wave was applied. The measurement was performed under conditions in which the prepared thin film fuel cell 100 was held in the air and methanol was supplied as fuel. The presence or absence of a short circuit between the electrode 21 and the electrode 22 was confirmed, and the battery characteristics were evaluated. When methanol was supplied as the fuel, an aqueous methanol solution was supplied to the Vycor glass 1 under the same conditions as the supply conditions at the time of open circuit voltage measurement.
5). Evaluation results

The measurement result of the open circuit voltage will be described with reference to FIGS. FIG. 8 shows a time-dependent change characteristic of the open circuit voltage generated between the electrode 21 and the electrode 22 when pure hydrogen is supplied as the fuel. FIG. 9 shows the time-varying characteristics of the open circuit voltage generated between the electrode 21 and the electrode 22 when methanol is supplied as the fuel.

Referring to FIG. 8, the measurement result of the change over time in the open circuit voltage when pure hydrogen is used as the fuel will be described. As shown in FIG. 8, the open circuit voltage when pure hydrogen was used as the fuel was about 0.016 V at the maximum when about 50 seconds passed after the supply of pure hydrogen was started. However, the voltage did not increase after that, and was almost 0 V after 150 seconds. From this result, it was found that sufficient electromotive force could not be obtained when pure hydrogen was supplied as fuel to the prepared thin film fuel cell 100. This is presumably because the element was not sufficiently humidified. It is known that Nafion constituting the electrolyte layer 6 has good proton conductivity in a state containing water. However, in this example, special moisture management was not performed particularly on the anode electrode layer side which is easy to dry. It is presumed that this was caused by insufficient humidification of Nafion.

Referring to FIG. 9, the measurement result of the change over time of the open circuit voltage when methanol is used as the fuel will be described. As shown in FIG. 9, the open circuit voltage when methanol was used as the fuel was about 0.2 V at the maximum when about 150 seconds had elapsed since the start of methanol supply. It has been found that it is possible to generate a significantly larger voltage than when pure hydrogen is used as fuel. From this result, it was revealed that the prepared thin film fuel cell 100 can be used as a battery.

The results of impedance measurement will be described with reference to FIG. FIG. 10 shows an impedance measurement result between the electrode 21 and the electrode 22 when the prepared thin film fuel cell 100 is placed in the air. Moreover, the impedance measurement result between the electrode 21 and the electrode 22 when methanol is supplied as the fuel is shown. A curve 41 is an impedance measurement result when the thin film fuel cell 100 is placed in the air. A curve 42 is an impedance measurement result in a state where methanol is supplied to the thin film fuel cell 100.

As shown in FIG. 10, from the result of the impedance measurement, the case where methanol is supplied as the fuel (curve 42), compared to the case where the thin film fuel cell 100 is placed in the air (curve 41), It was found that the impedance was greatly reduced. The reason is presumed that the moisture contained in the methanol fuel is supplied into the electrolyte layer 6 so that the electrolyte layer 6 is humidified and protons are more easily moved. Further, from the result of the frequency response, when the thin film fuel cell 100 is disposed in the air (curve 41) and when methanol is supplied as the fuel (curve 42), the frequency of the input signal is 100 kHz to 1 Hz. Under these conditions, it was found that the complex component of the impedance was 0 or less. In a state where a short circuit occurs between the electrode 21 and the electrode 22, the complex component of the impedance takes a positive value. From this, it was found that the prepared thin film fuel cell 100 was an ultrathin film but not short-circuited. Therefore, it has been clarified that no defect portion exists in the electrolyte layer 6.

Claims (17)

1. An electrolyte layer having a structure in which an anionic substance and a cationic substance are alternately laminated;
   An anode electrode layer and a cathode electrode layer disposed opposite to each other with the electrolyte layer interposed therebetween, wherein at least one of the anode electrode layer and the cathode electrode layer is alternately an anionic substance and a cationic substance A thin-film fuel cell comprising the anode electrode layer and the cathode electrode layer having a structure laminated on each other.
2. The thin film fuel cell according to claim 1, wherein the anionic substance constituting the electrolyte layer has a sulfo group or a phospho group.
3. The cationic substance constituting the electrolyte layer is any one of a primary amine salt, a secondary amine salt, a tertiary amine salt, and a quaternary ammonium salt. Or the thin film fuel cell of 2.
4. At least one of the anode electrode layer and the cathode electrode layer having a structure in which an anionic substance and a cationic substance are alternately laminated is that at least two layers of an anionic substance and a cationic substance are laminated. The thin film fuel cell according to any one of claims 1 to 3.
5. Equipped with a porous substrate,
   5. The thin film fuel cell according to claim 1, wherein at least one of the anode electrode layer and the cathode electrode layer is laminated on a surface side of the base substrate.
6. 6. The thin film fuel cell according to claim 5, wherein an electron conductive layer is formed on a surface of the base substrate.
7. The thin film fuel cell according to any one of claims 1 to 6, wherein an electron conductive layer is laminated on a surface of the anode electrode layer opposite to a surface in contact with the electrolyte layer.
8. The thin film fuel cell according to any one of claims 1 to 7, wherein an electron conductive layer is laminated on a surface of the cathode electrode layer opposite to a surface in contact with the electrolyte layer.
9. The thin film fuel cell according to claim 7 or 8, wherein the electron conductive layer laminated on the electrode layer has a structure in which an anionic substance and a cationic substance are alternately laminated.
10. 10. The thin film fuel cell according to claim 1, wherein an anionic substance constituting at least one of the anode electrode layer and the cathode electrode layer is a platinum colloid.
11. The charged polarity of the portion of the electrolyte layer in contact with the anode electrode layer is opposite to the charged polarity of the portion of the anode electrode layer in contact with the electrolyte layer,
    2. The charged polarity of a portion of the electrolyte layer in contact with the cathode electrode layer and the charged polarity of a portion of the cathode electrode layer in contact with the electrolyte layer are opposite in polarity. The thin film fuel cell according to any one of 1 to 10.
12. The thin film fuel cell according to any one of claims 1 to 11, wherein the thickness of the thin film fuel cell is 100 µm or less.
13. A first electrode layer forming step of forming one electrode layer of an anode electrode layer or a cathode electrode layer by alternately laminating an anionic substance and a cationic substance;
    An electrolyte layer forming step of forming an electrolyte layer by alternately laminating an anionic substance and a cationic substance on one surface of the one electrode layer formed in the first electrode layer forming step;
    By alternately laminating an anionic substance and a cationic substance on the surface of the electrolyte layer formed in the electrolyte layer forming step on the opposite side of the surface in contact with the one electrode layer, the anode electrode layer or A thin film fuel cell manufacturing method comprising: a second electrode layer forming step of forming the other electrode layer of the cathode electrode layers.
14. 14. The method of manufacturing a thin film fuel cell according to claim 13, wherein in the first electrode layer forming step, the cathode electrode layer or the anode electrode layer is formed on a surface side of a base substrate.
15. 15. The method of manufacturing a thin film fuel cell according to claim 14, wherein an electron conductive layer is formed on a surface of the base substrate.
16. At least one of the first electrode layer forming step and the second electrode layer forming step includes a conductive layer forming step of forming an electron conductive layer on a surface opposite to the surface in contact with the electrolyte layer. The method of manufacturing a thin film fuel cell according to claim 13.
17. The method of manufacturing a thin film fuel cell according to claim 16, wherein the conductive layer forming step forms the electron conductive layer by alternately laminating an anionic substance and a cationic substance.

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