JPH07249418A - Electrolytic film and manufacture thereof, and fuel cell - Google Patents

Abstract

PURPOSE:To manufacture an electrolyte film provided with passages formed inside thereof. CONSTITUTION:Multiple grooves are formed over the whole of one surface of an ion exchange membrane forming an electrolytic film (process 1). These grooves are formed by, for example, rotating a brushing roll, in which multiple nylon hairs are embedded, to push it to the surface of the ion exchange membrane, and the ion exchange membrane is bored by the nylon hairs. Two ion exchange membranes, which are respectively formed with multiple grooves over the whole of one surface thereof, are unified in condition that the surfaces formed with the grooves are arranged inside to form an electrolytic film (process 2). Two ion exchange membranes are unified by the hot-pressing for applying the pressure at 4MPa or 6MPa at 145 deg.C-155 deg.C of temperature. With these processes, the electrolytic film provided with passages formed inside thereof can be obtained.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrolyte membrane, a method for producing the same, and a fuel cell.

[0002]

2. Description of the Related Art In an anode of a fuel cell provided with an electrolyte membrane, a reaction of separating electrons from hydrogen to generate hydrogen ions is carried out as shown by the following equation, and in a cathode, hydrogen ions, electrons and oxygen are used. The reaction producing water is carried out. Hydrogen ions generated at the anode combine with water in the electrolyte membrane and move with the bound water in the electrolyte membrane to the cathode. Therefore, unless water is replenished to the anode side of the electrolyte membrane, the anode side of the electrolyte membrane gradually becomes insufficient in water, which may hinder the movement of hydrogen ions and stop the reaction. Therefore, in order to continuously carry out the electrode reaction, it is necessary to replenish the anode side of the electrolyte membrane with water to keep the electrolyte membrane in a wet state at all times.

Cathode reaction: 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O Anode reaction: H ₂ → 2H ⁺ + 2e ⁻

As a method for keeping the electrolyte membrane in a wet state,
It has been proposed to provide a passage inside the electrolyte membrane and supply water to the electrolyte membrane through the passage (for example, JP-A-4-259759). The electrolyte membrane used in this method is composed of two corrosion resistant twisted yarns arranged in parallel at regular intervals.
It is sandwiched between two ion exchange membranes, and in this state, a twisted yarn sandwiched between two ion exchange membranes is formed by integrating a temperature of 150 ° C. and a pressure of 5 MPa {51 Kgf / cm ² } at the same time. Provides a passage for water in the membrane.

Further, a fuel cell using this electrolyte membrane is
Two liquid reservoirs connected by a water passage formed in the electrolyte membrane are provided in the single cell, and water is supplied to the water passage of the electrolyte membrane by increasing the water pressure in one of the liquid reservoirs.

[0006]

However, in order to manufacture this electrolyte membrane, since it is necessary to uniformly supply water to the electrolyte membrane, it is necessary to dispose the knitting yarns at relatively narrow intervals, which makes the manufacture difficult. There was a problem that was. For example, in the electrolyte membrane described in Japanese Patent Application Laid-Open No. 4-259759, it is said that the twisted yarns having a diameter of about 0.1 mm are regularly arranged at intervals of about 1 mm, and it is necessary to arrange them with extremely high accuracy. In addition, since the twisted yarn is present in this electrolyte membrane in addition to the substantial passage of water, it has been a factor that hinders the thinning of the electrolyte membrane.

Further, in the fuel cell using this electrolyte membrane, there is a problem in that the liquid cell must be provided inside the unit cell and the structure becomes complicated. Further, in this fuel cell, there is a problem that the water pressure inside the liquid must be increased.

The electrolyte membrane, the method for producing the same, and the fuel cell according to the present invention solve these problems and easily produce an electrolyte membrane having passages formed therein, and a simple structure of a fuel cell using the electrolyte membrane. The following structure was adopted for the purpose of achieving the above.

[0009]

The electrolyte membrane of the present invention comprises 2
A gist is that a plurality of grooves are provided on at least one surface of one ion exchange membrane, and the two ion exchange membranes are integrated with the surface on which the groove is formed being inside.

The method for producing an electrolyte membrane of the present invention comprises a step of forming a plurality of grooves on at least one surface of at least one of the two ion exchange membranes, and a step of forming the two ion exchange membranes on the surface on which the groove is formed. The gist is that it consists of an integration process that integrates as the inside.

The fuel cell of the present invention is a fuel cell in which an electrolyte membrane and an electrode are laminated, and the electrolyte membrane is the electrolyte membrane according to claim 1, and the end portion of the groove of the electrolyte membrane. The gist of the present invention is to provide a water flow path that comes into contact with at least a part of the end surface having the.

[0012]

The electrolyte membrane of the present invention constructed as described above is
A plurality of grooves provided on one surface of at least one of the two ion-exchange membranes integrates the two ion-exchange membranes with the surface on which the grooves are formed as an inner side, so that a plurality of passages are formed inside the electrolyte membrane. To form.

In the method for producing an electrolyte membrane of the present invention, a plurality of grooves are provided on one surface of at least one of the two ion exchange membranes in the groove formation step, and the two ion exchange membranes are formed in the integration step. The formation surface of is integrated as the inside. Through this process, an electrolyte membrane having internal passages can be obtained.

In the fuel cell of the present invention, the water flow path allows water to flow from at least a part of the end face having the end portion of the groove of the electrolyte membrane to the passage inside the electrolyte membrane formed by the groove. Supply.

[0015]

Preferred embodiments of the present invention will be described below in order to further clarify the structure and operation of the present invention described above. First, a state of manufacturing an electrolyte membrane, which is an embodiment of the present invention, will be described based on the process diagram illustrated in FIG.

In step 1, a large number of grooves are formed on one side of the ion exchange membrane constituting the electrolyte membrane. Here, the ion exchange membrane forming the electrolyte membrane is formed of a polymer material, for example, a fluororesin, and exhibits good electric conductivity in a wet state. The thickness of the ion exchange membrane is 100 μm
To 200 μm, and 100 μm was used in the examples. The depth and width of many grooves formed in the ion exchange membrane are 5 μm to 50 μm, preferably 10 μm.
It is not necessary that the depths and the widths are uniform as long as the groove is in the range of 40 to 40 μm. In the examples, the depth and width of the groove are set to 5 μm to 50 μm because it is difficult to form passages by the hot pressing method described later when the depth and width are smaller than this range, and when it is larger than this range, the strength of the ion exchange membrane is high. Is small. Further, the multiple grooves formed may be regularly arranged in parallel or may be arranged in any direction. In this case, the grooves intersect and the whole becomes a stitch shape. In the embodiment, the groove is formed in two directions which are substantially orthogonal to each other.

FIG. 2 shows a method of forming a large number of grooves in the ion exchange membrane in the embodiment. FIG. 2 is an explanatory view showing a state in which a large number of grooves 22 are formed on the entire surface of the ion exchange membrane 20 with a nylon brushing roll 30. As illustrated, the brushing roll 30 is formed in a cylindrical shape by embedding a large number of bristles 32 of a fixed length in a mandrel 34. The groove 22 on the surface of the ion exchange membrane 20 is moved by rotating the brushing roll 30 about the mandrel 34 as an axis and pressing it against the ion exchange membrane 20 placed on a flat table, whereby the ion exchange membrane 20 is moved. Are formed by being brushed by the bristles 32 of the brushing roll 30. That is, the groove 22 is a large number of groove-shaped scratches formed on the surface of the ion exchange membrane 20 by the bristles 32 of the brushing roll 30. Therefore, the depth and width of the groove 22 can be adjusted by the material, thickness and length of the bristles 32 of the brushing roll 30, the strength with which the brushing roll 30 is pressed against the ion exchange membrane 20, and the like. In addition, brushing roll 3
The strength with which 0 is pressed against the ion exchange membrane 20 is determined by the material, the thickness, the length of the bristles 32 forming the brushing roll 30, the depth of the groove 22 formed, and the like. Hair 32
The thickness and length of the hair are determined by the material of the bristles 32, the width of the groove 22, and the like. Further, the operation of moving the brushing roll 30 while pressing it against the ion exchange membrane 20 to form the groove 22 is not limited to once, and the brushing roll 3
The operation of forming the groove 22 may be performed a plurality of times by changing the arrangement of 0 and the ion exchange membrane 20. In this case, the grooves 22 are formed in different directions by the number of arrangements of the brushing roll 30 and the ion exchange membrane 20.

In the embodiment, the thickness 1 made of nylon is used.
80 bristles 32 of 00 μm and 0.5 cm in length on the outer peripheral surface /
The brushing roll 30 is formed by embedding it in the mandrel 34 so as to be cm ^2, and the brushing roll 30 is inserted into the mandrel 3
4 is rotated at 500 rpm to 5000 rpm, preferably 1000 rpm to 3000 rpm, and the ion exchange membrane 20 is pressed so that the distance between the center of the mandrel 34 and the surface of the ion exchange membrane 20 is shortened by 0.15 mm to 3 mm. The groove 22 was formed by moving the brushing roll 30 in a direction substantially orthogonal to the mandrel 34 which is the rotation axis. The operation of forming the groove 22 was performed twice by changing the arrangement of the brushing roll 30 and the ion exchange membrane 20 by about 90 degrees. The average value of the grooves 22 thus formed was 80 μm in width, and the amount thereof was 3 m / cm ² . The appearance of the ion exchange membrane 20 in which the groove 22 is formed is shown in FIG. As shown in the figure, a large number of grooves 22 formed on the surface of the ion exchange membrane 20 are formed in a plurality of directions and have a mesh shape. In addition, although the bristles 32 are formed of nylon in the embodiment, they may be formed of any material as long as they have the strength capable of forming the grooves in the ion exchange membrane 20.

In step 2 of FIG. 1, the two ion-exchange membranes 20 each having a large number of grooves 22 formed on one surface thereof are integrated so that the grooves face inward to form an electrolyte membrane 40. In the examples, at a temperature of 120 ° C. to 160 ° C., preferably 145 ° C. to 155 ° C., 1 MPa {10.2 Kgf / cm ² } to 10 MPa {102 Kgf / cm ² }, preferably 4 MPa.
They were integrated by a hot pressing method in which a pressure of {41 Kgf / cm ² } to 6 MPa {61 Kgf / cm ² } was applied.

FIG. 4 shows how the ion exchange membrane 20 is integrated. FIG. 4A is an enlarged cross-sectional view showing an enlarged part of the cross section of the ion exchange membrane 20 before being integrated. FIG. 4B is an enlarged cross-sectional view illustrating a part of the cross section of the electrolyte membrane 40 when the two ion exchange membranes 20 are integrated to form the electrolyte membrane 40. As shown in FIG. 4A, the two ion exchange membranes 20 are integrated by a hot pressing method with the surface having the grooves 22 formed inside to form an electrolyte membrane 40. In the electrolyte membrane 40 thus integrated, as shown in FIG. 4B, the groove 2 of the ion exchange membrane 20 is formed.
2 forms a passage 42 inside the membrane.

In the method for manufacturing the electrolyte membrane of the above-described embodiment, a large number of grooves are formed on one surface of the ion exchange membrane 20, and the two ion exchange membranes 20 having the grooves are formed with the grooves. An electrolyte membrane having a large number of passages inside can be formed by integrating the formed surface inside. Further, as compared with a method of manufacturing an electrolyte membrane by integrating by a hot press method with two twisted yarns that are regularly arranged at a narrow interval sandwiched between two ion exchange membranes, an electrolyte having a passage inside is much easier. Membranes can be manufactured.

The passage 4 of the electrolyte membrane 40 thus manufactured
By contacting a part of the end surface having two end portions with water, the water can be supplied to the electrolyte membrane 40 through the passage 42 by the capillary phenomenon. Further, since a large number of grooves 22 are formed in the surface of the ion exchange membrane 20 in a plurality of directions and a mesh-shaped passage 42 is formed in the electrolyte membrane 40, the mesh-shaped passage 4 is formed.
The electrolyte membrane 40 can be obtained by simply contacting part of the end portion of 2 with water.
It is possible to make a wide range of the wet state. Further, since foreign matters such as twisted yarn do not coexist in the electrolyte membrane 40, it is possible to prevent deterioration of the function of the electrolyte membrane due to the foreign matters.

Although the groove 22 is formed on both of the two ion exchange membranes in the embodiment, the groove 22 may be formed on only one of the ion exchange membranes. In this case, in the polymer electrolyte fuel cell, water on the anode side of the electrolyte membrane is insufficient, so it is preferable to use the ion exchange membrane having the groove 22 on the anode side. In addition, in the embodiment, the grooves 22 are formed on the surface of the ion exchange membrane 20 by the brushing roll 30.
Although the groove 22 is formed, the groove 22 may be formed by scratching with a comb-shaped object. In the embodiment, the brushing roll 30 is evenly pressed against the ion exchange membrane 20 so that the grooves 22 are evenly formed on the entire surface of the ion exchange membrane 20. However, the ion exchange membrane 20 is integrated and the electrolyte membrane 4 is formed.
After being set to 0, the electrolyte membrane 40 comes into contact with water and the electrolyte membrane 4
When the groove 22 is formed in a portion where water is supplied into 0, that is, a portion which becomes an end portion of the electrolyte membrane 40, the brushing roll 30 is strongly pressed against the ion exchange membrane 20 to have a width or width larger than those of other portions. A configuration in which the groove 22 having a large depth is formed is also suitable. When the groove 22 is formed in this manner, the electrolyte membrane 4
The opening area of the passage 42 opening to the end of 0 becomes large,
Water can be easily supplied to the electrolyte membrane 40.

Next, an example of a fuel cell that suitably uses the electrolyte membrane 40 thus manufactured will be described. The fuel cell includes a laminated body 105, a fuel gas supply device (not shown) for supplying a fuel gas to the laminated body 105, and the laminated body 10.
5 and a water supply device (not shown) for supplying water. FIG. 5 is a perspective view illustrating the appearance of the laminated body 105.

As shown in the figure, the laminated body 105 includes a battery module 200 having three unit cells 250 and the laminated body 1
A plurality of cooling members 500 for cooling 05 are stacked. The stack 105 includes four fuel gas flow channels 110a to 110d penetrating the stack 105 in the stacking direction,
Similarly, four water channels 120a to 120d are formed to penetrate the laminated body 105 in the laminating direction.

FIG. 6 is a cross-sectional view schematically showing the cross section of the battery module 200 and the cooling member 500 (cross section AA of FIG. 8 described later). As shown in the figure, the unit cell 250 in the battery module 200 includes an electrolyte membrane 40, two electrodes 50 having a sandwich structure with the electrolyte membrane 40 sandwiched from both sides, and mixing of fuel gas into the side portions of the electrodes 50. Two gaskets 620 for preventing the fuel gas, a gasket 610 for preventing the fuel gas from leaking to the outside, a sandwich structure and two electrodes for sandwiching the gasket 610 from both sides and forming a fuel gas flow path with the electrode 50. 300
Or 400.

FIG. 7 shows a perspective view of a sandwich structure formed by the electrolyte membrane 40 and the two electrodes 50. As shown in the figure, the electrolyte membrane 40 has a substantially square shape, and a rectangular business trip portion 44 is formed on each side. The end of the above-mentioned passage 42 is formed at the end of the outer edge of the electrolyte membrane 40. This business trip unit 44, when the unit cell 250 is formed,
The laminated body 105 is exposed to the inside of a water channel 120a or the like that penetrates in the laminating direction (see FIG. 6). Therefore, the water flow path 12
The water flowing through the channel 0a and the like flows into the water channel 120a and the electrolyte membrane 40
Due to the pressure difference between the inside and the inside of the electrolyte membrane, the capillary phenomenon is introduced into the electrolyte membrane 40 from the end of the business trip portion 44 through the passage 42.

The electrode 50 is formed of a carbon cloth woven from threads made of carbon fibers, and carbon powder carrying platinum or a platinum-alloy alloy as a catalyst is carried on the carbon cloth. Is kneaded into the surface and the gap on the side of the electrolyte membrane 40. The electrolyte membrane 40 and the two electrodes 50 are 1 MPa {10.2 Kgf / at a temperature of 120 ° C. to 160 ° C., preferably 145 ° C. to 155 ° C., with the two electrodes 50 sandwiching the electrolyte membrane 40 in a sandwich structure. cm ² } to 15 MPa
{153 Kgf / cm ² } preferably 5 MPa {51 Kgf / c
They are joined by a hot press method in which a pressure of m ² } to 10 MPa {102 Kgf / cm ² } is applied to join.
In the embodiment, the electrode 50 is formed of carbon cloth, but it is also preferable that the electrode 50 is formed of carbon paper or carbon felt made of carbon fiber.

The collecting electrode 300 is formed of gas-impermeable carbon that is made gas-impermeable by compressing carbon. FIG. 8 is a perspective view illustrating the appearance of the collecting electrode 300. As shown in the drawing, the collector electrode 300 is formed in a square plate shape, and eight rectangular holes (fuel holes 310a to 310d) penetrating in the stacking direction are formed near each side of the stacking surface.
And water flow passage holes 320a to 320d) are formed. The fuel hole 310a and the water flow path holes 320a and the like are stacked when the members are stacked to form the stacked body 105.
To form four fuel gas passages 110a to 110d and four water passages 120a to 120d.

At the center of the stacking surface (the surface shown in FIG. 8) of the collector electrode 300, a step portion 330a which is recessed from the periphery by one step is formed. The step portion 330a and the fuel hole 310a are formed.
Ribs 332a and 332c are formed between the fuel hole 310c and the fuel hole 310c. Further, the step portion 330a is formed with a plurality of ribs 336a arranged parallel to the direction of the water flow passage hole 320c on the opposite side from the fuel hole 310a. These ribs 332a, 332c, 336a form the fuel gas passages 334a, 334c, 338a with the electrode 50 or the gasket 620 which are in close contact with each other when stacked (see FIG. 6).

Also on the back surface of the surface of the collector electrode 300 on which the step portion 330a is formed (the back surface of the surface shown in FIG. 8), step portions and ribs 332d and 336b having the same shape as the surface on which the step portion 330a is formed. Etc. are formed, and the step portion 330
The ribs on the surface on which a is formed are orthogonal to the ribs on the back surface. Ribs 332d and 336b on the back surface
Etc., the fuel gas passages 334d, 338b, etc. are formed with the electrode 50 or the gasket 620 that are in close contact when laminated (see FIG. 6). Therefore, the fuel gas passages 338a and 338b formed on both surfaces of the collector electrode 300 are orthogonal to each other.

The collector electrodes 400 are located at both ends of the battery module 200, and form a cooling water passage 538, which will be described later, with the cooling member 500 mounted on the battery module 200. Therefore, the collector electrode 400 is formed of gas-impermeable carbon similarly to the collector electrode 300, and its shape is the same as one of the case where the collector electrode 300 is divided into two parts on a plane parallel to the laminated surface. That is, the fuel hole 310 of the collector electrode 300 shown in FIG.
a to 310d, water flow passage holes 320a to 320d,
Fuel holes 410a to 410d corresponding to the step portion 330a, the rib 332a, the rib 332c and the rib 336a,
Water channel holes 420a to 420d, a step portion 430, a rib 432a, a rib 432b, and a rib 436 are formed (see FIG. 6), and the other side of the stacking surface of the collector electrode 400 is
Nothing has been formed. The two collector electrodes 400 attached to both ends of the battery module 200 are arranged such that the surfaces on which the ribs 436 are formed are inside and the ribs 436 are orthogonal to each other.

Gasket 620 and gasket 610
Is formed of a sealing material (for example, silicone RTV rubber, Teflon sheet, PFA sheet or film). Further, as shown in FIG. 6, the end portion of the electrolyte membrane 40 facing each fuel gas flow channel 110c and the like is sealed by a seal member 630 so that fuel gas does not enter the passage 42. The seal member 630 is made of the same material as the gasket 620.

FIG. 9 is a perspective view illustrating the appearance of the cooling member 500. The cooling member 500 is made of gas impermeable carbon. As shown, the cooling member 50
0 has a plate-like shape with a square surface to be stacked, and the stacking surface has the same hole (fuel hole) at the same position as the fuel hole 310a and the water flow path hole 320a formed in the collecting electrode 300. 510a to 510d, cold flow passage holes 320a to 3
20b) has been formed. The fuel holes 510a and the cold flow path holes 320a and the like also have four fuel gas flow paths 110a to 110d and 4 that penetrate the stacked body 105 in the stacking direction.
Two water channels 120a to 120d are formed. A plurality of parallel ribs 536 are formed in the central portion of the cooling member 500, and the ribs 536 form a water flow path hole 520a and a water flow path hole 520c with the collector electrode 400 that comes into close contact when stacked.
A plurality of cooling water passages 538 are formed so as to communicate with each other in a folded manner. Therefore, if the cooling water is caused to flow through one of the water flow path holes (for example, the water flow path hole 520a), the cooling water is guided to the other water flow path hole (for example, the water flow path hole 520c) through the passage 538.

Battery module 200 constructed in this way
And the cooling member 500 are laminated to form a laminated body 105. One of the two sets of fuel gas passages facing each other of the stacked body 105 (for example, the fuel gas passage 11
0a and 110c) as an inflow passage and an exhaust passage of an oxygen-containing gas that is a cathode fuel, and the other set of fuel gas passages (for example, the fuel gas passages 110b and 110d) of a hydrogen-containing gas that is an anode fuel. With the inflow passage and the exhaust passage, the cathode fuel and the anode fuel flow in the fuel gas passages 338a and 338b which are orthogonal to each other with the electrolyte membrane 40 interposed therebetween, and the two electrodes 5 arranged on both sides of the electrolyte membrane 40 are provided.
Both fuels are supplied to 0, the electrochemical reaction shown by the above-mentioned formula is performed, and chemical energy is directly converted into electrical energy.

Of the four water channels that penetrate the laminated body 105, two water channels (for example, water channels 120a and 120b) that are not at opposite positions are used as water supply channels, and the other two water channels (for example, water channels). If the water flows through the water flow paths 120c and 120d) as the water discharge paths, the water flows through the cooling water passages 538 of the cooling member 500 to cool the laminated body 105. When water is flowed through the water channel 120a or the like, the water passes through the passage 42 from the end of the business trip portion 44 of the electrolyte membrane 40 through the passage 42 due to a pressure difference between the water channel 120a or the like and the inside of the electrolyte membrane 40 or a capillary phenomenon. The electrolyte membrane 40 is supplied to the membrane 40 and becomes wet.

The fuel cell of the above-described embodiment has an excellent effect that water can be supplied to the electrolyte membrane 40 only by exposing a part of the electrolyte membrane 40 in the water channel 120a and the like. Therefore, the electrolyte membrane 40 can always be kept in a wet state, the internal resistance of the fuel cell can be kept small, and the operating efficiency of the fuel cell can be kept high. Further, the water flow path for supplying water to the cooling member 500 and the electrolyte membrane 4
Since it also serves as a water flow path for supplying water to the fuel cell 0, the fuel cell can have a simple structure, and the fuel cell can be downsized.

In the embodiment, four trip parts 44 are provided on the electrolyte membrane 40, but any number may be used as long as the entire electrolyte membrane 40 is replenished with water. Further, in the embodiment, the business trip portion 44 is exposed to the water flow path 120a and the like on the electrolyte membrane 40, but it may not be exposed if the end portion of the business trip portion 44 is in contact with the water flow passage 120a. In the embodiment, the water flow path 120 a for supplying water to the electrolyte membrane 40 and the like are provided in the cooling member 500.
Although it is configured to also serve as a water flow path for supplying water to the above, it may be configured separately. Furthermore, in the embodiment, the battery module 200 is composed of three unit cells 250, but the number of unit cells 250 forming the battery module 200 is not limited. In the embodiment, the electrolyte membrane 40 having a uniform thickness is used, but it is also preferable to increase the thickness of the business trip portion 44 exposed in the water flow path to increase the contact area with water.

Next, the case where the laminated body 105 of the embodiment is constructed as the fuel cell system 100 shown in FIG. 10 will be described. As shown, the fuel cell system 100
Is composed of the laminated body 105 and a control device 900 for controlling the operating state of the laminated body 105.

A blower 710 for supplying an oxygen-containing gas that is the cathode side fuel to the stack 105 is connected to the fuel gas flow path 110a of the stack 105 via a pipe 712, and a pipe is connected to the fuel gas flow path 110b. A blower 720 that supplies a hydrogen-containing gas that is an anode-side fuel is connected to the stacked body 105 via 722. Therefore, when the blowers 710 and 720 are operated, the cathode fuel and the anode fuel flow in the fuel gas passages 338a and 338b that are orthogonal to each other with the electrolyte membrane 40 interposed therebetween, and the cathode fuel and the anode fuel flow to both electrodes 50 arranged on both sides of the electrolyte membrane 40. Both fuels are supplied and the electrochemical reaction shown in the above formula is performed. The blower 710 and the blower 720 are connected to the control device 900.

Further, the water channel 1 formed in the laminated body 105.
A pump 730 that supplies cooling water to the stacked body 105 via a pipe 732 is connected to 20 a and 120 b. When the pump 730 is operated, the cooling member 500
The cooling water is supplied to the passage 538 of FIG. The pump 730 is also connected to the control device 900.

A temperature sensor 850 for measuring the temperature inside the laminated body 105 is installed, and this temperature sensor 850 is connected to the control device 900. Both ends of the laminated body 105 are connected to an output terminal 820 for extracting electric power from the fuel cell system 100 by an electric conduction line 810, and a voltmeter 830 for measuring the voltage V of the electric power taken out is taken out to the electric conduction line 810. An ammeter 840 that measures the electric current I is installed. The voltmeter 830 and the ammeter 840 are also connected to the control device 900.

The control device 900 is configured as a logic circuit centered on a microcomputer, and more specifically, it is necessary for the CPU 910, which executes predetermined arithmetic operations according to a preset control program, to execute various arithmetic processing. From a ROM 920 in which various control programs and control data are stored in advance, a RAM 930 in which various data necessary for executing various arithmetic processes in the CPU 910 are temporarily read and written, a voltmeter 830, an ammeter 840, and a temperature sensor 850. An input processing circuit 940 for inputting a detection signal and a blower 71 according to the calculation result in the CPU 910.
An output processing circuit 950 that outputs a drive signal to the 0, 720 and the pump 730 is provided. With the control device 900 configured in this manner, the blowers 710 and 720 and the pump 730 are based on the power generation state of the laminated body 105 detected by the voltmeter 830, the ammeter 840, and the temperature sensor 850.
Are driven and controlled.

In this fuel cell system 100, the cooling water is controlled by the controller 900 in the cooling water control routine shown in FIG. The cooling water control routine will be described below. This routine is performed every predetermined time (for example, every 100 msec) after the fuel cell system 100 is driven.
To be executed.

When this routine is executed, first, the CPU
910 executes a process of reading the voltage V detected by the voltmeter 830, the current I detected by the ammeter 840, and the temperature T detected by the temperature sensor 850 through the input processing circuit 940 (step S1000). Then, based on the read voltage V and current I, the pump 7
The basic rotation speed N of 30 is calculated (step S1010).
The basic rotation speed N of the pump 730 is determined by a map (not shown) showing the relationship among the voltage V, the current I, and the basic rotation speed N. This map shows the number of rotations of the pump 730 that supplies the cooling water so that the stack 105 has a temperature at which the stack 105 operates efficiently when the voltage V and the current I of the electric power extracted from the fuel cell system 100 are the voltage V and the current I, respectively. It was created by experiment. Regarding the voltage V, the current I, and the basic rotation speed N, generally, when the voltage V or the current I is increased, the heat generation by the laminated body 105 also increases. Also shows the relationship of becoming larger.

Next, the predetermined value Tset is subtracted from the temperature T detected by the temperature sensor 850 to obtain the deviation ΔT (step S1020), and the control variable K is calculated based on this deviation ΔT.
Is calculated (step S1030). Here, the predetermined value Ts
et is a numerical value set as a temperature at which the stacked body 105 operates efficiently, and is determined by the characteristics of the stacked body 105. The control variable K is a positive value that is 1 when the deviation ΔT is 0, smaller than 1 when the deviation ΔT is negative, and larger than 1 when the deviation ΔT is positive. is there. Further, the control variable K is obtained in consideration of the temperature responsiveness of the laminated body 105 when the rotation speed of the pump 730 is changed. When the control variable K is calculated, the CPU
910 calculates the instruction rotation speed Ne to the pump 730 by multiplying the basic rotation speed N of the pump 730 by the control variable K (step S1040), and performs the output processing so that the rotation speed of the pump 730 becomes the calculated instruction rotation speed Ne. A drive signal is output via the circuit 950 (step S1050), and this routine ends.

Therefore, the pump 730 increases the voltage V or the current I to increase the electric power taken out from the fuel cell system 100 (when the electrode reaction becomes active) or when the laminated body 105 is operated. When the internal resistance increases and the amount of heat generated by the laminated body 105 increases, the rotation speed increases. When the number of rotations of the pump 730 increases, the water flow path 12 to which water is supplied by the pump 730.
The hydraulic pressure of 0a and 120b becomes high. As a result, the pressure difference between the water channels 120a and 120b and the inside of the electrolyte membrane 40 becomes large, and the water is pushed into the passage 42 having the opening in the business trip portion 44 exposed in the water channels 120a and 120b, and the electrolyte membrane 40 is discharged. Increased water supply. That is, when the electrode reaction is actively performed to increase the amount of water required on the anode side of the electrolyte membrane 40, or when the electrolyte membrane 40 lacks water and the internal resistance of the laminate 105 increases, the cooling water is increased. The water flow paths 120a and 120a are controlled by the control routine.
The pressure difference between 20b and the electrolyte membrane 40 increases, and the amount of water supplied to the electrolyte membrane 40 via the passage 42 increases.

In the fuel cell system 100 described above, the temperature of the stack 105 can be maintained at a high operating efficiency by controlling the rotation speed of the pump 730 based on the operating state of the stack 105. The necessary water can be supplied to the electrolyte membrane 40 to keep the electrolyte membrane 40 in a wet state at all times.

In the embodiment, the fuel cell system 10
The basic rotation speed N of the pump 730 is obtained based on the output of 0 (voltage V and current I), and the rotation of the pump 730 is further multiplied by the control variable K based on the deviation ΔT from the temperature at which the stacked body 105 operates efficiently. Although the number is controlled, the rotation number of the pump 730 may be controlled based on the temperature T of the laminated body 105. In this case, since the temperature T of the stacked body 105 and the output of the fuel cell system 100 are in a substantially proportional relationship, it is possible to obtain the same effect as the control based on the output of the fuel cell system 100 described above.

The embodiments of the present invention have been described above.
The present invention is not limited to these examples, and it goes without saying that the present invention can be implemented in various modes without departing from the scope of the present invention.

[0051]

As described above, in the electrolyte membrane of the present invention, a plurality of grooves are provided on one surface of at least one of the two ion exchange membranes, and two ion exchange membranes are formed with the surfaces on which the grooves are formed inside. By integrating the above, it is possible to form a plurality of passages inside the electrolyte membrane. Further, since only a plurality of grooves are provided on the surface of the ion exchange membrane to form a plurality of passages inside the electrolyte membrane, foreign matters do not coexist in the electrolyte membrane, and the performance of the electrolyte membrane due to the mixture of foreign matters can be improved. The decrease can be prevented. Of course, since a plurality of passages are formed inside the electrolyte membrane, water can be supplied to the electrolyte membrane through the plurality of passages by a capillary phenomenon or the like simply by bringing the end of the passage into contact with water. .

In the method for producing an electrolyte membrane of the present invention, a plurality of grooves are provided on at least one surface of at least one of the two ion exchange membranes in the groove formation step, and the two ion exchange membranes are formed in the integration step. By integrating the formation surface of the inside as
An electrolyte membrane having a plurality of passages inside can be formed extremely easily.

In the fuel cell of the present invention, since the water flow path which comes into contact with at least a part of the end surface having the end of the groove of the electrolyte membrane according to claim 1 is provided, the inside of the electrolyte membrane formed by this groove is formed. The water can be supplied to the passage to keep the electrolyte membrane in a wet state at all times. Therefore, the fuel cell can be continuously and efficiently operated without running out of water in the electrolyte membrane.

[Brief description of drawings]

FIG. 1 is a process diagram illustrating the state of manufacturing an electrolyte membrane that is an example of the present invention.

FIG. 2 is a brushing roll 30 for the ion exchange membrane 20.
FIG. 6 is an explanatory view showing a state in which a large number of grooves 22 are formed on the entire surface of the.

FIG. 3 is an explanatory diagram illustrating the appearance of the ion exchange membrane 20 having grooves 22 formed therein.

FIG. 4 is an explanatory view illustrating a state in which the ion exchange membrane 20 is integrated.

5 is a perspective view illustrating the appearance of a laminated body 105. FIG.

FIG. 6 is a cross-sectional view of a battery module 200 and a cooling member 500.

FIG. 7 is a perspective view illustrating the appearance of a sandwich structure formed by an electrolyte membrane 40 and two electrodes 50.

8 is a perspective view illustrating the appearance of a collector electrode 300. FIG.

9 is a perspective view illustrating the appearance of a cooling member 500. FIG.

FIG. 10 is a block diagram illustrating the configuration of a fuel cell system 100.

FIG. 11 is a flowchart illustrating a cooling water control routine executed by the control device 900 of the fuel cell system 100.

[Explanation of symbols]

20 ... Ion exchange membrane 22 ... Groove 30 ... Brushing roll 32 ... Hair 34 ... Mandrel 40 ... Electrolyte membrane 42 ... Passage 44 ... Business trip section 50 ... Electrode 100 ... Fuel cell system 105 ... Laminated bodies 110a, 110b, 110c, 110d ... Fuel Gas channel 120a, 120b, 120c, 120d ... Water channel 200 ... Battery module 250 ... Single cell 300 ... Collection electrode 310a, 310b, 310c, 310d ... Fuel hole 320a, 320b, 320c, 320d ... Water channel hole 330a ... Step portion 332a, 332c, 332d ... Rib 336a, 336b ... Rib 334a, 334c, 334d ... Passage 338a, 338b ... Passage 400 ... Collection electrode 410a ... Fuel hole 420a ... Water flow passage hole 430 ... Step portion 432a, 432b ... Rib 436 ... Rib 500 ... Cooling member 51 a, 510b, 510c, 510d ... Fuel hole 520a, 520b, 520c, 520d ... Water channel hole 536 ... Rib 538 ... Passage 610 ... Gasket 620 ... Gasket 630 ... Seal member 710, 720 ... Blower 712, 722 ... Pipe 730 ... Pump 732 ... Pipe 810 ... Conducting line 820 ... Output terminal 830 ... Voltmeter 840 ... Ammeter 850 ... Temperature sensor 900 ... Control device 910 ... CPU 920 ... ROM 930 ... RAM 940 ... Input processing circuit 950 ... Output processing circuit

Claims (3)

[Claims] 1. A plurality of grooves are provided on one surface of at least one of two ion exchange membranes, and the two ion exchange membranes are
An electrolyte membrane integrally formed with the groove forming surface as the inside. 2. A groove forming step of providing a plurality of grooves on at least one surface of at least one of the two ion exchange membranes, and an integrating step of integrating the two ion exchange membranes with the groove forming surface inside. And a method for producing an electrolyte membrane. 3. A fuel cell in which an electrolyte membrane and an electrode are laminated, wherein the electrolyte membrane is the electrolyte membrane according to claim 1, wherein at least an end surface having an end of the groove of the electrolyte membrane is formed. A fuel cell with a water flow path that contacts some.