JPH08273687A - Supply gas humidifier of fuel cell - Google Patents

Abstract

PURPOSE: To provide a compact humidifier having high humidifying efficiency. CONSTITUTION: An inside space of a jacket 12 sandwiched by a pair of partition plates 13 and 14 constitutes a water chamber 18, and an inlet 19 and an outlet 20 of water are formed in positions in close vicinity to the respective partition plates 13 and 14, and cooling water piping is connected, and fuel gas is introduced to an inside space of respective hollow thread films from the side of one partition plate 13 of a hollow thread film bundle 11 supported with a pair of partition plates 13 and 14 of the jacket 12. It flows toward the side of the other partition plate 14, and is guided to the other gas chamber 17, and on the other hand, cooling water is introduced to the inside space 18 of the jacket 12 from the inlet '19 arranged on the side of the partition plate 14 on the gas outlet side, and flows in the opposite direction of the gas flowing direction while indirectly contacting with gas flowing inside of it from outside of the hollow thread films 1, and is discharged from the side of the partition plate 13 on the gas inlet side. The fuel gas is introduced so as to flow in the opposite direction of the cooling water in a humidifier 7, and is humidified by contacting with the cooling water through the hollow thread films.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polymer electrolyte fuel cell.

[0002]

2. Description of the Related Art In general, a polymer electrolyte fuel cell is a power generating element formed by sandwiching a hydrogen ion conductive solid polymer between carbon electrodes carrying a platinum catalyst, that is, a solid polymer electrolyte membrane-electrode junction. While defining gas passages for supplying respective reaction gases to the body and each electrode surface,
It has a structure in which a gas separation member supporting the power generation element from both sides is laminated. Then, one electrode is supplied with hydrogen gas, that is, fuel gas, and the other electrode is supplied with oxygen or air, that is, oxidant gas, so that the chemical energy involved in the redox reaction of the fuel gas is directly extracted as electric energy. Has become. That is, on the anode side, hydrogen gas is ionized and moves in the solid polymer electrolyte, and the electrons move to the cathode side through an external load and react with oxygen to generate water. It can extract energy. Since hydrogen ions move along with the solid polymer electrolyte membrane, if the solid polymer electrolyte membrane is dried, the ionic conductivity is lowered and the energy conversion efficiency is lowered. Therefore, it is necessary to supply water to the solid polymer electrolyte membrane in order to maintain good ionic conduction.

[0003]

In a conventional polymer electrolyte fuel cell, a humidifying mechanism actively humidifies a reaction gas to maintain a high reaction rate. This humidifier is designed to humidify the gas by bringing the gas and water into contact with each other. However, in order to ensure a desired gas wet state, a contact area between the predetermined gas and water is secured. Will be required. In the conventional structure, the reaction gas is brought into contact with water through a porous carbon plate to humidify the gas. However, with this configuration, the humidification efficiency is not necessarily good, and there is a problem that the device becomes large. Also, JP-A-6-1320
Japanese Unexamined Patent Publication No. 38-38 discloses a fuel gas humidifying device using a water vapor permeable membrane. In the disclosed humidifier, the feed gas is humidified by bringing the fuel gas and the off gas into contact with each other via the water vapor permeable membrane. However, in this device, there is a problem that the device becomes large in size similarly to the above due to its structure.

The present invention is configured from such a point of view, and an object thereof is to provide a compact humidifier having high humidification efficiency and to downsize a polymer electrolyte fuel cell. A further object of the present invention is to effectively reduce the size of the polymer electrolyte fuel cell without installing a special humidifier by incorporating a unique humidification mechanism into the polymer electrolyte fuel cell.

[0005]

In order to achieve the above object, the present invention is configured as follows. That is, a humidifier for a supply gas of a fuel cell according to the present invention includes a power generating element including a solid electrolyte membrane and electrode constituent members arranged on both sides of the polymer electrolytic membrane, and a power generating element along the power generating element. A gas separating member, which is arranged and defines a gas flow path for the reaction gas supplied to the power generation element between the power generation element and a gas separation member, and the respective reaction gases generate electricity on both sides of the power generation element. A fuel cell having a cell configured to be provided so as to be capable of supplying to the element is characterized in that the reaction gas and water are brought into contact with each other through a hollow fiber membrane to humidify the reaction gas. More specifically, in the above, the humidifying device includes a gas chamber in which a reaction gas flows and a water chamber in which water flows, and the gas chamber is connected to a reaction gas supply pipe to the fuel cell, The chamber is connected to the cooling water pipe of the fuel cell. Further, a predetermined amount of the hollow fiber membranes may be arranged in a gas circulation region defined by the gas separating member, the hollow fiber membranes being configured to allow water to flow inside.

Further, the fuel cell is constructed by stacking the cells and is provided with a gas supply passage for supplying a reaction gas to each cell in the stacking direction of the cells. In this case, a predetermined amount of the hollow fiber membrane is arranged in the gas supply passage, and water is circulated inside the hollow fiber membrane. Alternatively, in another aspect, a drainage passage for cooling water is provided in a region that divides each cell. Then, a predetermined amount of hollow fiber membranes capable of circulating only water is arranged in such a drainage passage, and gas is allowed to flow in the hollow fiber membranes.

[0007]

As described above, in order to keep the hydrogen ion conduction of the polymer electrolyte membrane good and to keep the activity of the electrochemical reaction high, it is necessary to increase the humidity of the supply gas. The present invention is characterized in that a hollow fiber membrane is used to humidify the supply gas. The hollow fiber membrane is a membrane of a thin fiber which is literally hollow, and has a property that the flow of gas is blocked but the flow of water, that is, water molecules is allowed. In this case, water flows through the hollow fiber membrane from the direction of high water vapor partial pressure to the direction of low water vapor partial pressure. Therefore, when water is present inside the hollow fiber membrane and gas is present outside, the moisture moves to the outer gas phase through the hollow fiber membrane. On the contrary, when gas is circulated inside the hollow fiber membrane and water is circulated outside, the water permeates from the outside of the hollow fiber membrane to the inside and diffuses into the gas.
Therefore, when configuring a gas humidifier for application to the present invention, which gas or water is present inside or outside the hollow fiber membrane is a design matter and can be appropriately selected. The mass transfer of water vapor through the hollow fiber membrane can be represented by the following equation.

Q = P × Am × (Pf-Pp) where Q: Water vapor transmission rate (cm3 / sec) P: Water vapor transmission coefficient (cm3 / cm2 / sec / cmHg) Am: Membrane area (cm2) Pf: Supply-side water vapor partial pressure (cmHg) Pp: Permeation-side water vapor partial pressure (cmHg) The permeation coefficient of the hollow fiber membrane that can be effectively applied to the humidifying device of the present invention is 1.0 × 10 ^{−8 to} 1.0. × 10 ^-5 (cm
3 / cm2 / sec / cmHg) is preferred. Examples of the material of the hollow fiber membrane suitable for the present invention include polymer ion exchange membranes such as phenol sulfonic acid, polystyrene sulfonic acid, polytrifluorostyrene sulfonic acid, perfluorocarbon sulfonic acid, and the like. Any one can be selected as long as it has a transmission coefficient of. Also, the hollow fiber membrane can be effectively used up to a level of several microns if the outer diameter is about 3 mm or less. When the humidifier is constituted by the hollow fiber membrane, the area of the membrane per unit amount of gas and water used is extremely large as compared with the conventional planar membrane,
A water-gas contact area can be efficiently secured.
In particular, when a hollow fiber membrane is used in the application of the present invention, a predetermined amount of the hollow fiber membrane is used in a bundle, and therefore the surface area of the membrane becomes extremely large with respect to the volume ratio. Therefore, the conventional humidifier can be significantly reduced in size.

Further, the bundle-shaped hollow fiber membranes may be arranged in a common water or gas passage for each cell of the polymer electrolyte fuel cell so as to make water-gas contact. For example, by utilizing spaces such as a gas supply passage, a discharge passage, and a cooling water supply / discharge passage extending in the cell stacking direction, gas or water is circulated inside the hollow fiber membrane to move water through the hollow fiber membrane. The gas can be humidified. In this case, since the hollow fiber membrane bundle is simply incorporated inside the existing structure, it is not necessary to provide a special gas humidifier.

[0010]

Embodiments of the present invention will be described below. FIG. 1 shows a principle diagram of a hollow fiber membrane applicable to the present invention. The hollow fiber membrane 1 is composed of a fine tube-shaped ion exchange membrane having an outer diameter of several millimeters to several microns. The hollow fiber membrane that can be suitably used in the present invention has a property of allowing the flow of water but blocking the flow of gas. In this case, the water flows from the side with a high water vapor partial pressure to the side with a low water vapor partial pressure. Therefore, when water is present on one side of the hollow fiber membrane and gas is present on the other side, mass transfer of water always occurs from the water phase to the gas phase through the hollow fiber membrane. That is, the water flows in the direction of increasing the humidity of the gas. In FIG. 1, water circulates outside the hollow fiber membrane 1,
Fuel gas or oxidant gas is circulated inside. Due to the above properties, the dry gas (air) initially introduced into the hollow fiber membrane is in a dry state containing no water on the inlet side (lower side in the figure). That is,
It contains only nitrogen molecules 2 and oxygen molecules 3. However, as it flows through the inner space 1a of the hollow fiber membrane 1 toward the outlet (upward in the figure), the water 4 existing outside the hollow fiber membrane 1 permeates into the hollow fiber membrane and becomes water vapor 5. The humidity of the gas inside diffuses in the internal space 1a of the hollow fiber membrane 1 and rises. Since the water vapor permeability coefficient of the hollow fiber membrane 1 is known in advance, the amount of the hollow fiber membrane 1 is set by setting the total surface area of the hollow fiber membrane 1 so as to obtain a predetermined wet state of the feed gas of the fuel cell. Alternatively, the length can be set appropriately.

Referring to FIGS. 2 and 3, there is shown an example in which a humidifying device is constructed by preparing a predetermined amount of the hollow fiber membrane. In FIG. 2, a polymer electrolyte fuel cell 6 to which the present invention can be applied is arranged. The humidifying device 7 of this example is provided as an external addition device to the fuel cell 6. That is, the illustrated humidifying device functions as a humidifying device for fuel gas, and on the other hand, it is installed independently of the fuel cell 6 and is connected to the fuel gas supply line to the fuel cell. The fuel cell 6 is constructed by stacking a predetermined number of plate-shaped cells 8 as power generating elements and attaching end plates 9 to both ends thereof. In this example, cooling water is used as the humidifying water. For this purpose, a cooling water line 10 of the fuel cell is connected to the humidifying device 7. Referring to FIG. 3, there is shown a schematic cross-sectional view of the humidifying device 7, and the humidifying device 7 of this example has a structure like a multi-tube heat exchanger and has a multi-tube structure, that is, an assembly of hollow fiber membranes. Fuel gas circulates inside the hollow fiber membrane bundle 11 that is a body, and cooling water circulates inside the jacket 12 that houses the hollow fiber membrane bundle 11. In this case, water circulates outside the hollow fiber membrane 1 and fuel gas circulates inside the hollow fiber membrane. The both ends of the hollow fiber membrane bundle 11 are fixed by partition plates 13 and 14 that block the space between the inner surface of the jacket 12 and the surface of the hollow fiber membrane bundle 11 in a watertight state. Gas chambers 16 and 17 are defined on the outer sides of the pair of partition plates 13 and 14 as extensions of the jacket 12. A fuel gas supply line 15 is connected to the gas chambers 16 and 17.

On the other hand, the inner space of the jacket 12 sandwiched between the pair of partition plates 13 and 14 constitutes a water chamber 18. In this water chamber 18, each partition plate 13,
A water inlet 19 and an outlet 20
Is formed, and a cooling water pipe is connected to this inlet / outlet. In this case, the fuel gas flows from one partition plate side 13 (from the left side in FIG. 3) of the hollow fiber membrane bundle 11 supported by the pair of partition plates 13 and 14 of the jacket 12 into the inner space of each hollow fiber membrane. It is introduced, flows toward the other partition plate 14 side, and is guided to the other gas chamber 17. On the other hand, the cooling water is introduced into the internal space 18 of the jacket 12 from the inlet 19 provided on the side of the partition plate 14 on the gas outlet side,
While indirectly contacting the gas flowing inside from the outside of the hollow fiber membrane 1, the hollow fiber membrane 1 flows in the direction opposite to the flow direction of the gas and is discharged from the partition plate 13 side on the gas inlet side.
As described above, the fuel gas is introduced so as to flow in the humidifying device 7 in the direction opposite to the cooling water, and is contacted with the cooling water through the hollow fiber membrane to be humidified. In this case, since the hollow fiber membrane is incorporated in the humidifier 7 as an aggregate as described above, contact per unit amount of gas is greater than that in the case where gas-water contact is performed using a flat membrane. The area can be greatly increased. Therefore, the humidifier can be made compact.

Referring to FIG. 4, a humidifying device 7 according to another embodiment of the present invention is shown. The humidifying device 7 of this example is also an external addition type to the fuel cell 6 as in the previous example. The structure of this example is different from the preceding example in that the cooling water is circulated inside the hollow fiber membrane 1 and the fuel gas is circulated outside so that gas-water contact is performed through the hollow fiber membrane. That is the point. Therefore, the fuel gas is introduced from the inlet 19 provided near the partition plate 13 of the jacket 12 of the humidifier, flows along the hollow fiber membrane bundle 11, and is provided at the outlet near the other partition plate 14. Emitted from 20. Areas outside the pair of partition plates 13 and 14 form cooling water chambers 16 and 17. Then, it is introduced into the inside of each hollow fiber membrane from one chamber (the right side in FIG. 4 in this example) 17 and flows in the hollow fiber membrane in the direction opposite to the gas to the side of the other partition plate 13. Is discharged to. Also in this example, the same effect as the previous example can be obtained. Still another embodiment of the present invention will be described with reference to FIGS. The polymer electrolyte fuel cell 30 to which the present invention is applied is formed by stacking thin plate-shaped power generation cells 31. Further, each cell 31 further includes a catalyst electrode 3 from both sides with a solid polymer membrane 32 interposed therebetween as shown in FIG.
3, 34 are arranged, one of which constitutes an anode electrode and the other of which constitutes a cathode electrode. Further, a pair of separators 35 and 36 having a current collecting function are arranged on both sides thereof to form gas passages 37 and 38 for supplying a fuel gas to the anode electrode and an oxidant gas to the cathode electrode, respectively. Since the projections 39 are in contact with the electrodes, a space is defined between the surfaces of the electrodes and the gas passages 37 and 38 are formed.

The convex portion 39 constitutes a current collecting portion for extracting the electric power generated by the contact with the electrode. This polymer electrolyte membrane 32, a pair of catalyst electrodes 33, 34
And the pair of separators 35, 36 is one cell 3
Make up 1. A single fuel cell 30 is formed by stacking a predetermined number of the cells 31 and disposing end plates at both ends of the stack. In this case, in order to remove heat generated by the electrolytic reaction, a plate provided with a cooling water passage is arranged every time a predetermined number of cells 31 are stacked, and a cooling water passage is provided on this plate.
The entire plane is cooled evenly. And
In order to introduce a predetermined gas into each of the stacked cells 31 and to introduce cooling water into each of a predetermined number of stacking stages of cells, the fuel cell 30 extends in the stacking direction of the cells, and A common gas supply / exhaust passage and cooling water supply / exhaust passage are provided for each cell. That is, when one cell is formed in one stacking stage, fuel gas, oxidizing gas, and cooling water supply and discharge passages are required, so a total of six passages extending in the stacking direction are formed. This passage is formed in each stacking stage by forming an opening in a portion corresponding to the above passage in a region other than a portion where cells are formed.

In this embodiment, as shown in FIG.
The hollow fiber membrane bundle 41 is arranged in the fuel gas supply common passage 40, and the internal space of the hollow fiber membrane bundle 41 constitutes a part of the cooling water discharge passage. That is, in FIG. 6, the cooling water is introduced into the fuel cell 30 by the cooling water supply common passage 44 extending in the direction of the broken arrow, and is made to flow in parallel along the plane in which the cells extend in a predetermined stacking stage, and the respective planes. One drainage passage 4 at the end of the
5 and is guided to the side opposite to the cooling water introduction side. Then, on the other end side, the flow direction is reversed and introduced into the internal space of the hollow fiber membrane bundle 43 arranged in the fuel gas supply passage 42. Then, the fuel gas is caused to flow in a direction opposite to the introduction direction. On the other hand, the fuel gas is introduced from one end portion (the left end portion in FIG. 8) of the fuel cell having a laminated structure, and the space outside the hollow fiber membrane 43 is not defined as the flow direction of the cooling water. Flows in the opposite direction. During this time, the fuel gas and the cooling water come into contact with each other through the hollow fiber membrane,
The fuel gas reaches a predetermined wet state. After this, the fuel gas is introduced into the gas passage along the electrode surface of each cell 31 as shown by the arrow in the figure.

In the example of FIG. 6, the hollow fiber membrane bundle 41 is arranged in the fuel gas supply passage to bring the cooling water into contact with the fuel gas, but the same applies to the oxidant gas. Depending on the configuration, a predetermined wet state of the oxidant gas can be obtained. In this example, since the humidifying mechanism can be configured by disposing the hollow fiber membrane bundle in the existing fuel gas supply passage 40, it is not necessary to provide the humidifying device separately from the fuel cell, and the fuel cell 30 can be made small. can do. Referring to FIG. 7, yet another embodiment of the present invention is shown. In the configuration of this example, unlike the previous example,
A cooling water discharge passage 42 extending in the stacking direction of the fuel cell 30.
A hollow fiber membrane bundle 43 is arranged inside, and fuel gas is allowed to pass through the inside. That is, in the configuration of the present example, the internal space of the hollow fiber membrane bundle 43 has the fuel gas supply passage 4
Used for part of 2. Also in this example, the same effect as the previous example can be obtained. Referring to FIG. 8, there is shown a humidifying device according to still another embodiment of the present invention. In the previous two examples, the hollow fiber membrane bundle is arranged in the passage extending in the cell stacking direction, that is, in the common passages 40, 42 for each cell. Each cooling water passage 46 in the cooling water supply plate composed of the separators 57 and 58 provided in the
A humidifying mechanism is configured by arranging a hollow fiber membrane 47 through which the fuel gas flows inside.

In the cell stack type fuel cell, the cooling mechanism for each cell is composed of a pair of separators arranged along the surface of the cell. That is, in FIG. 8, another separator 58 having irregularities is fitted to the back surface of one separator 57, and the convex portion 48 comes into contact with the back surface of the one separator 57, so that the direction along the surface of the cell is increased. A cooling water passage 46 is formed to allow the cooling water to flow therethrough. A hollow fiber membrane 47 is arranged in each cooling water passage 46, and the fuel gas flows through the inside thereof. In this case, an appropriate number of hollow fiber membranes are arranged in each cooling water passage. The hollow fiber membrane 47 may be configured to be directly branched from the fuel gas supply passage and arranged in the cooling water passage 46, or by branching the hollow fiber membrane bundle arranged in the common gas passage, the cooling water passage 46 of each cell. It may be arranged at. By doing so, the surface area of the hollow fiber membrane bundle arranged in the cooling water passage extending in the stacking direction can be reduced. As a result, it is possible to reduce the increase width of the cross-sectional area of the cooling water passage, which is necessary to secure a space for arranging the hollow fiber membrane bundle for humidifying the gas in the cooling water passage. Referring to FIG. 9, there is shown a partially enlarged sectional view of a fuel cell according to still another embodiment of the present invention.

This example has a common point with the previous example in that the hollow fiber membrane is arranged in the passage provided in the direction along the lamination surface of the laminated structure, but in this example, inside the laminated structure of the cell 50, A characteristic point is that the hollow fiber membranes 51 are arranged to configure a humidifying mechanism. That is, in the present example, the catalyst electrodes 5 arranged on both sides of the polymer electrolyte membrane 52.
Separator 55 abutting on 3, 54 and the separator 55
An appropriate number of hollow fiber membranes 51 are arranged in the fuel gas passage formed by the surface of the catalyst electrode with which the cooling electrode abuts, and the cooling water flows through the inside. In this case, it can be configured by branching the cooling water passage from the common cooling water passage extending in the stacking direction of the cells by the hollow fiber membrane and arranging the hollow fiber membrane in the fuel gas passage 56 of each cell. Further, when the hollow fiber membrane bundle is arranged in the common fuel gas passage 56, the small hollow fiber membrane bundle 5 is removed from this hollow fiber membrane bundle.
1 may be branched so as to be arranged in the fuel gas passage formed in the stacking plane of each cell. In this example as well, the gas required for humidifying the gas is the same as in the previous example.
The water contact surface area can be ensured within the existing structure. When the hollow fiber membrane bundle is arranged in the fuel gas supply passage as described above, the passage cross-sectional area for the flow of the fuel gas is reduced. When it is arranged also in the gas passage in the stacking plane of each cell, the hollow fiber membrane bundle surface area for gas-water contact of the hollow fiber membrane bundle arranged in the fuel gas supply passage extending in the stacking direction is set to that value. It can be reduced. Therefore, it is possible to incorporate the humidifying device having a desired capacity while suppressing the modification of the existing structure provided in the fuel cell as much as possible.

In the above structure, the fuel cell in which a single cell is formed in one stack unit of the fuel cell has been described. However, the present invention has a stack structure in which a plurality of cells are incorporated in one stack unit. Type fuel cells can be similarly applied. Still another embodiment of the present invention will be described with reference to FIGS. In this example, a humidifier equipped with a hollow fiber membrane is installed in the exhaust passage of the oxidant gas so that the reaction supply gas can be circulated inside the hollow fiber membrane and the oxidant gas can be circulated outside the hollow fiber membrane. It has become. In this case, FIGS. 10 to 12 show an externally installed humidifying device, and FIG. 13 shows an internally installed humidifying mechanism. In FIG. 10, dry reaction gas 60
Are humidified by being in contact with the humid oxidant exhaust gas 61 through the hollow fiber membrane 1 in an opposed manner. In this case, 5 water molecules
Only the hollow fiber membrane 1 moves to the inside 1a. Note that FIG.
The reference numerals used in FIGS. 12 to 12 indicate that the structure of the humidifier is basically the same as that of the embodiment shown in FIGS. 2 to 4, and the contact between the gas and the water through the hollow fiber membrane is the oxidant exhaust gas. Since they may be replaced with the reaction supply gas (combustion gas or oxidant gas), the same reference numerals are used. Also, FIG.
Similarly, in the third embodiment, the structure in which the hollow fiber membrane bundle is arranged so that the reaction supply gas flows inside the oxidant exhaust passage is the same as the relationship between the fuel gas and the cooling water in FIG. Is used.

[0020]

As described above, according to the present invention, in the solid polymer electrolyte membrane fuel cell, the humidifying device has a much larger gas-water contact area per unit amount of gas than the conventional device. Since the hollow fiber membrane having high efficiency is used, the humidifying device can be downsized. Further, since the hollow fiber membrane has an extremely small diameter, it can be incorporated into the structure of an existing fuel cell by forming it into a bundle having an appropriate size and using it in a humidifying mechanism. According to this structure, it is not necessary to provide the humidifying device as an external addition device of the fuel cell. In this case, the above-mentioned hollow fiber membrane bundle can be incorporated as a gas-water contact device into a common gas or cooling water passage extending in the fuel cell stacking direction to function as a humidifying device.
By arranging the hollow fiber membrane in the gas passage or the cooling water passage in the stacking surface of the fuel cell, the gas
The water contact surface area can be secured, and the fuel cell can be further downsized. Further, the application of the hollow fiber membrane bundle to the humidification mechanism is not limited to the conventional fuel cell in which a single cell is incorporated in one stacking stage, and a polymer of a type in which a plurality of cell structures are incorporated in the same plane. The same can be applied to the electrolytic membrane stacked fuel cell.

Water produced by the reaction is mixed in the oxidant exhaust gas. Conventionally, this generated water is discharged to the outside of the fuel cell stack together with the oxidant exhaust gas, and is stored in a humidification (cooling) water tank or discharged outside the system. As the water for humidification, it is necessary to use pure water in order to prevent the solid polymer film from being contaminated by impurities and deteriorating the performance. Therefore, when the cooling water is used as the humidifying water, it is necessary to remove impurities such as metal ions with a filter when circulating the cooling water. In this respect, when the humidifying device according to the present invention is used, the moisture in the oxidant exhaust gas moves into the reaction supply gas and is humidified, so that it is not necessary to separately supply water for humidification, and the metal ion It is not necessary to consider such problems, and it is possible to use antifreeze as cooling water. Therefore, in addition to the need for a filter, it is advantageous in that the startability at low temperatures can be improved.

[Brief description of drawings]

FIG. 1 is a conceptual diagram for explaining the operation of a hollow fiber membrane applicable to the present invention,

FIG. 2 is a schematic view of a polymer electrolyte fuel cell incorporating a humidifying device according to one embodiment of the present invention,

3 is a schematic cross-sectional view of the humidifier shown in FIG.

FIG. 4 is a view similar to FIG. 2 according to another embodiment of the present invention,

FIG. 5 is a sectional view conceptually showing the structure of a cell of a fuel cell to which the present invention can be applied.

FIG. 6 is a schematic sectional view of a humidifier for a polymer electrolyte fuel cell according to still another embodiment of the present invention,

FIG. 7 is a view similar to FIG. 6 according to still another embodiment of the present invention,

FIG. 8 is a schematic sectional view showing the concept of a humidifier according to still another embodiment of the present invention,

FIG. 9 is a view similar to FIG. 8 of a humidifier according to still another embodiment of the present invention,

FIG. 10 is a conceptual diagram showing a contact state between a dry reaction supply gas and a wet oxidant exhaust gas,

FIG. 11 is a view similar to FIG. 2, showing an embodiment relating to contact between a reaction supply gas and an oxidant exhaust gas;

FIG. 12 is a view similar to FIG. 3 of the embodiment relating to the contact between the reaction gas and the oxidant exhaust gas;

FIG. 13 is a view similar to FIG. 7 of still another embodiment relating to the contact between the reaction gas and the oxidant exhaust gas.

[Explanation of symbols]

 1 Hollow Fiber Membrane, 2 Nitrogen Molecules, 4 Oxygen Molecules, 6 Fuel Cell, 7 Humidifier, 10 Cooling Water Line, 11 Hollow Fiber Membrane Bundle, 12 Jacket, 13 14 Partition Plate, 15 Fuel Gas Line, 30 Fuel Cell, 31 Cell, 32 polymer electrolyte membrane, 33, 34 catalyst electrode, 37, 38 gas passage, 50 fuel cell, 51 hollow fiber membrane, 55 separator, 56 gas passage.

Claims (7)

[Claims] 1. A power generation element comprising a solid polymer electrolyte membrane and electrode constituent members arranged on both sides of the solid polymer electrolyte membrane; and a power generation element arranged along the power generation element and supplied to the power generation element. And a gas separation member made of a conductive material for defining a gas flow path for the reaction gas between the power generation element and the gas separation member formed on both sides of the power generation element so that the respective reaction gases can be supplied to the power generation element. In a fuel cell having a cell constituted by the above, a supply gas humidifier for a fuel cell, wherein the reaction gas and water are brought into contact with each other through a hollow fiber membrane to humidify the reaction gas. 2. A power generating element composed of a solid polymer electrolyte membrane and electrode constituent members arranged on both sides of the solid polymer electrolyte membrane, and arranged along the power generating element and supplied to the power generating element. And a gas separation member made of a conductive material for defining a gas flow path for the reaction gas between the power generation element and the gas separation member formed on both sides of the power generation element so that the respective reaction gases can be supplied to the power generation element. In the fuel cell having a cell constituted by the above, the supply gas of the fuel cell is characterized in that the reaction supply gas and the oxidant exhaust gas are brought into contact with each other through the hollow fiber membrane so as to humidify the reaction supply gas. A supply gas humidifier for a fuel cell, characterized in that it is configured to flow. 3. The humidifier according to claim 1, further comprising a gas chamber in which a reaction gas flows and a water chamber in which water flows, the gas chamber being connected to a reaction gas supply pipe to the fuel cell, A supply gas humidifier for a fuel cell, wherein the water chamber is connected to a cooling water pipe of the fuel cell. 4. The hollow fiber membrane according to claim 1, wherein a predetermined amount of the hollow fiber membrane is arranged in a gas flow region defined by the gas separating member. A supply gas humidifier for a fuel cell. 5. The fuel cell according to claim 1, wherein the fuel cell is constructed by stacking the cells and is provided with a gas supply passage for supplying a reaction gas to each cell in a stacking direction of the cells. And a predetermined amount of the hollow fiber membrane is disposed in the gas supply passage, and water is circulated inside the hollow fiber membrane. apparatus. 6. The fuel cell according to claim 1, wherein the fuel cell is constructed by stacking the cells, and a gas flow passage for supplying and exhausting a reaction gas to and from each cell in a stacking direction of the cells is provided. A fuel cell is provided, in which a predetermined amount of the hollow fiber membrane is arranged in the reaction gas exhaust passage, and a reaction supply gas is circulated inside the hollow fiber membrane. Supply gas humidifier. 7. The fuel cell according to claim 1, wherein the fuel cell is constructed by stacking the cells, and a water passage for supplying cooling water for cooling each cell is provided in a stacking direction of the cells. A supply gas humidifier for a fuel cell, characterized in that a predetermined amount of hollow fiber membranes are arranged in the water passage, and a gas is allowed to flow in the hollow fiber membranes.