JP6739970B2 - Fuel cell stack - Google Patents

Description

Embodiments of the present invention relate to a fuel cell stack.

A fuel cell system directly converts the binding energy of hydrogen in fuel gas and oxygen in air into electricity. Therefore, the power generation system has high power generation efficiency and is excellent in environment. This fuel cell system generally includes a fuel cell stack, a reformer, a control unit, and other devices. This fuel cell stack is configured by stacking a plurality of fuel cell units. Fuel gas containing hydrogen is produced from the reformer and supplied to the fuel cell stack. Further, each device in the fuel cell system is controlled by the control unit, and electricity, water, and heat generated by power generation of the fuel cell stack are taken out to the outside. In the fuel cell stack, the fuel gas containing hydrogen produced in the reformer is supplied to the fuel electrode of the fuel cell, and the air is supplied to the oxidant electrode of the fuel cell to generate electricity by an electrochemical reaction. The polymer electrolyte fuel cell is a fuel cell in which a polymer electrolyte membrane having proton conductivity is used as an electrolyte of the fuel cell.

A fuel cell stack of a polymer electrolyte fuel cell supplies a fuel cell formed by sandwiching a polymer electrolyte membrane on both sides with a fuel electrode and an oxidant electrode, and supplying a fuel gas and air to the fuel electrode and the oxidant electrode. And a separator in which a gas flow path for forming the gas flow path is alternately laminated. A fuel gas inlet manifold, a fuel gas outlet manifold, an air inlet manifold, and an air outlet manifold are arranged in this fuel cell stack. The fuel gas and the air supplied from the fuel cell system are introduced into the fuel gas inlet manifold and the air inlet manifold, respectively, and are supplied to each cell through a gas flow path communicating with the manifold. The vapor generated by the reaction product water in the fuel cell and the gas not used in the reaction are discharged to the fuel gas outlet manifold and the air outlet manifold that communicate with each other from the gas flow path.

The proton resistance of the polymer electrolyte membrane is inversely proportional to the water content. That is, in order to reduce the resistance and enhance the power generation performance, it is necessary to humidify the polymer electrolyte membrane to increase the water content. As a method of humidifying the polymer electrolyte membrane, an external humidification method of supplying vapor into fuel gas or air and an internal humidification method of supplying water as a liquid through a separator are known.

Further, in order to maintain the temperature of the fuel cell within an appropriate range, it is necessary to cool the heat generated in the fuel cell reaction. In a cogeneration system that uses reaction heat as well as electricity obtained by power generation, cooling water is flowed to cool the fuel cell stack, and heat recovered from the cooling water is used as hot water. The water flow path for flowing the cooling water is formed on the back surface of the separator having the gas flow path, and the two flow path separators are used with the water flow path surface inside.

Furthermore, using a conductive porous plate having fine pores as a separator, by providing a water flow path in each cell, water is supplied to the fuel cell through the conductive porous plate to humidify the separator, There is known a latent heat cooling method of cooling by the latent heat of vaporization of water from the surface. In this latent heat cooling method, the pressure of the fuel gas and the air is made higher than the pressure of the cooling water to remove the generated water and condensed water by the conductive porous plate, and at the same time, the entire reaction surface of the fuel cell is removed. It realizes humidification and cooling.

Patent Document 2 reports a fuel cell stack that supplies cooling water from the side surface of the conductive porous plate. In the fuel cell stack in which the above-mentioned water flow path is introduced into all cells, two separators are required for each cell, which increases the cost. On the other hand, if cooling water is supplied from the side surface of the separator, the cost of the separator can be reduced because the water flow path is not necessary.

Japanese Patent Publication No. 11-508726 Japanese Patent No. 4738979

In the fuel cell stack that supplies cooling water from the side surface of the conductive porous plate, the cooling water is first introduced into the cooling water manifold arranged on the surface in contact with the long side of the rectangular separator of the fuel cell stack. Cooling water other than the water supplied to the fuel cell from the side surface of the separator passes through the flow passages formed in the end plates at both ends of the fuel cell stack, and goes out of the fuel cell stack from the cooling water outlet manifolds that are arranged facing each other. Is discharged.

However, there is a problem that the structure for forming the water flow path in the end plate is complicated and difficult to process. Further, although cells near both ends of the fuel cell stack can be cooled, heat removal is insufficient in the central cell, and there is a problem that a temperature difference occurs between the central cell and cells near both ends.

The problem to be solved by the present invention is to provide a fuel cell stack that can be cooled more efficiently.

The fuel cell stack according to the present embodiment is a laminated body in which a plurality of fuel cells and separators made of a porous material are alternately laminated, and at least one of the separators is the laminated body. A water flow channel group at N locations penetrating from a first side surface along the stacking direction to a second side surface opposite to the first side surface, where N is an integer of 2 or more, and is a separator. A body and (N+1) cooling water manifolds.

According to the present invention, the fuel cell stack can be cooled more efficiently.

FIG. 3 is a schematic diagram showing the appearance of a fuel cell stack. The schematic diagram which shows the laminated structure of a laminated body. The schematic diagram which shows the cross section of a fuel cell. The schematic diagram which shows the side surface of a 1st separator. The schematic diagram which shows the water flow path formed in the side surface of a 2nd separator and one surface of a 2nd member. The schematic diagram which shows the cross section of a cooling water manifold and the water flow path group formed in one surface of a 2nd member. The schematic diagram which shows the crank-shaped water flow path formed in the one surface of a 2nd member.

Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
In the fuel cell stack according to the first embodiment, it is possible to achieve more efficient cooling of the fuel cell stack through the water flow passage by forming the laminated body using the second separator in which the water flow passage is formed. It was done.

The configuration of the fuel cell stack 1 according to the first embodiment will be described. FIG. 1 is a schematic diagram showing the appearance of the fuel cell stack 1. The fuel cell stack 1 according to the first embodiment is a device that generates electricity by an electrochemical reaction in a fuel cell. That is, the fuel cell stack 1 includes a stack 10, a first cooling water manifold 12, a second cooling water manifold 14, a third cooling water manifold 16, and a fourth cooling water manifold 18. The fifth cooling water manifold 20, the sixth cooling water manifold 22, the first fuel gas manifold 24, the second fuel gas manifold 26, the first air manifold 28, and the second air manifold 30. And. Here, in order to display the manifold in an easy-to-understand manner, an example is shown in which a gap is provided between the manifold and the stack 10, but in an actual machine, the manifold is attached so as to be in contact with the stack 10. In the following description, the description may be made with reference to the coordinate system indicated by X, Y, and Z. Here, the Z-axis direction coincides with the horizontal direction and the Y-axis direction coincides with the vertical direction.

The stacked body 10 generates power by an electrochemical reaction between a fuel gas containing hydrogen and air containing oxygen. In this stack 10, a plurality of water flow passages penetrating between the first side surface 10a along the stacking direction of the fuel cell stack 1, that is, along the Z-axis, and the second side surface 10b opposite to the first side surface 10a. Are formed. The laminated body 10 is sandwiched between a pair of tightening plates 11, and is tightened by a load in the stacking direction by a tie rod or a band (not shown in the drawing).

The cooling water manifolds 12, 14, 16, 18, 20, 22 are provided on the first side surface 10a and the second side surface 10b, and supply and discharge the cooling water used for humidifying and cooling the laminated body 10. Further, these cooling water manifolds 10, 12, 14, 16, 18, 20, 22 supply and discharge the cooling water through the water flow paths formed in the laminated body 10. That is, as shown by a dotted arrow, the cooling water introduced into the first cooling water manifold 12 from the cooling water inlet 122 is stored in the cooling water manifolds 12, 14, 16, 18, 20, 22 and the laminated body 10. The water is discharged from the cooling water outlet 222 of the sixth cooling water manifold 22 by alternately passing through the water flow paths.

The first fuel gas manifold 24 is provided with a fuel gas inlet 242 which is an inlet for fuel gas containing hydrogen, and is arranged on the third side face 10c along the stacking direction of the fuel cell stack 1, that is, along the Z axis. That is, the first fuel gas manifold 24 supplies the fuel gas containing hydrogen supplied from the fuel gas inlet 242 to the stacked body 10.

The fuel gas outlet 262 is formed in the second fuel gas manifold 26, and the second fuel gas manifold 26 is disposed on the fourth side face 10d, which is the side face opposite to the third side face 10c. That is, the second fuel gas manifold 26 discharges the gas not consumed by the electrochemical reaction in the stacked body 10 from the fuel gas outlet 262.

The first air gas manifold 28 has an oxidant gas inlet 282 formed therein and is arranged on the fourth side face 10d. That is, the first air gas manifold 28 supplies the air supplied from the oxidant gas inlet 282 to the stacked body 10.

The second air gas manifold 30 has an air gas outlet 302 formed therein and is arranged on the third side face 10c. That is, the second air gas manifold 30 discharges the air not consumed by the electrochemical reaction from the air gas outlet 302.

Next, the laminated structure of the laminated body 10 will be described. FIG. 2 is a schematic diagram showing a laminated structure of the laminated body 10. Here, the XZ plane of the laminated body 10, that is, the third side face 10C of the laminated body 10 is shown with reference to FIG. As shown in FIG. 2, the laminated body 10 is formed by alternately stacking a plurality of fuel cells 102 and separators 104 and 106 made of a porous material. The fuel cell 102 generates electricity, water, and heat by an electrochemical reaction due to an electrochemical reaction between hydrogen in the supplied fuel gas and oxygen in the air.

The first separator 104 is made of a porous material. By evaporating the cooling water filled in the pores of the porous material, the fuel cell unit 102 is humidified and cooled. This porous material is, for example, a conductive porous material.

The second separator 106 is made of a porous material. By evaporating the cooling water filled in the pores of the porous material, the fuel cell unit 102 is humidified and cooled. This porous material is, for example, a conductive porous material. In addition, a plurality of water flow paths are formed in the second separator 106. As a result, the cooling water is caused to flow through the plurality of water flow paths, whereby the laminated body 10 is cooled via the second separator 106. For this reason, the second separator 106 is arranged at a position in the laminated body 10 where heat removal may be insufficient due to insufficient heat removal with only the first separator 104.

The fuel cell 102 and the separators 104 and 106 here have a rectangular shape. Further, the main surface 102a and the main surface 102b of the fuel cell unit are XY planes. Similarly, the main surfaces 104a and 104b of the first separator 104 are XY planes, and the main surfaces 106a and 106b of the second separator 106 are XY planes.

Next, the configuration of the fuel cell unit 102 will be described. FIG. 3 is a diagram showing a cross-sectional view of the fuel cell unit 102. The fuel cell 102 is configured to include a polymer electrolyte membrane 102c, an oxidizer electrode 102d, and a fuel electrode 102e. The polymer electrolyte membrane 102c is, for example, a polymer electrolyte membrane having proton conductivity.

The oxidant electrode 102d is formed on one surface of the polymer electrolyte membrane 102c. Air as an oxidant gas containing oxygen is supplied to the oxidant electrode 102d. The oxidant electrode 102d is formed by a catalyst layer 102f that performs an electrochemical reaction and a gas diffusion layer 102g.

The fuel electrode 102e is formed on the other surface of the polymer electrolyte membrane 102c. Fuel gas containing hydrogen is supplied to the fuel electrode 102e. The fuel electrode 102e is formed of a catalyst layer 102h that performs an electrochemical reaction and a gas diffusion layer 102i. As described above, the fuel cell 102 is configured to have the oxidizer electrode 102d on one main surface 102a of the polymer electrolyte membrane and the fuel electrode 102e on the other main surface 102b.

Next, the configuration of the first separator 104 will be described. FIG. 4 is a schematic diagram showing a side surface of the first separator 104. A fuel gas flow passage 1040a is formed on one surface of the first separator 104. An oxidant gas flow passage 1040b is formed on the other surface of the first separator 104.

The cooling water directly contacts the first side surface 10a and the second side surface 10b (FIG. 1) of the stacked body 10. Then, as shown by a dotted arrow, the cooling water supplied from the side surfaces humidifies the polymer electrolyte membrane 102c through the fine pores of the porous material, and from both main surfaces 104a and 104b of the first separator 104. It is cooled by the latent heat of vaporization of water. Further, the pressure of the fuel gas and the air is set higher than the pressure of the cooling water. As a result, the generated water and condensed water are removed by the conductive porous material, and the humidification and cooling of the entire reaction surface of the laminate 10 are realized.

Next, the configuration of the second separator 106 will be described. FIG. 5 is a schematic view showing a water flow path formed on the side surface of the second separator 106 and one surface of the second member 1064. The second separator 106 is configured by bonding a first member 1062 and a second member 1064.

The first member 1062 forms an oxidant gas flow passage 1060b. That is, one surface of the first member 1062 is a flat surface, and the oxidant gas flow passage 1060b is formed on the other surface.

The second member 1064 forms a plurality of water flow paths 108, 110, 112, 114, 116 and a fuel gas flow passage 1060a. That is, the plurality of water flow paths 108, 110, 112, 114, 116 are formed on one surface of the second member 1064, and the fuel gas flow passage 1060a is formed on the other surface.

As described above, in the second separator 106, the first member 1062 and the second member 1064 are adhered to each other, so that the fuel gas flow passage 1060a is formed on one main surface 106a and the oxidant gas is formed on the other main surface 106b. A flow passage 1060b is formed, and a plurality of water flow paths 108, 110, 112, 114, 116 are formed between the main surfaces. That is, five linear water channels 108, 110, 112, 114, 116 are formed in the second separator 106 in parallel with the X axis. As described above, the second water flow channel 110 is formed above the first water flow channel 108, that is, vertically above, and the third water flow channel 112 is further formed above the second water flow channel 110. Further, a fourth water channel 114 and a fifth water channel 116 are sequentially formed above the third water channel 112.

Further, as shown by a dotted arrow, the cooling water supplied from the side surfaces humidifies the polymer electrolyte membrane 102c through the fine pores of the porous material, and from both main surfaces 106a and 106b of the second separator 106. It is cooled by the latent heat of vaporization of water. Furthermore, the cooling water is supplied from one flow path opening of the water flow path and is discharged from the other flow path opening as indicated by the solid arrow. As a result, the second separator 106 is cooled by the latent heat of vaporization and also directly cooled by the cooling water. The cooling water is also supplied to the porous material of the second separator 106 from the plurality of water flow paths 108, 110, 112, 114, 116. As can be seen from this, the cooling capacity of the second separator 106 is higher than that of the first separator 104.

As described above, the second separator 106 is arranged in a region that needs to be cooled more strongly. Furthermore, the plurality of water channels 108, 110, 112, 114, 116 of the second separator 106 form channels for supplying and draining cooling water. As can be seen from this, by stacking the second separator 106 having the plurality of water channels 108, 110, 112, 114, and 116 formed on the laminated body 10, it is not necessary to form the water channel outside the laminated body 10. Of. Thereby, the structure of the laminated body 10 can be formed into a rectangular parallelepiped, and the cooling capacity for the laminated body can be adjusted. Further, since the plurality of water flow paths 108, 110, 112, 114, 116 are formed linearly, the resistance to cooling water is further reduced and the accumulation of gas or air in the water flow paths is suppressed.

Furthermore, since the second separator 106 is not arranged in a place where the cooling of the first separator 104 is sufficient, it is possible to further reduce the number of used second separators 106. The second separator 106 is configured by bonding a first member 1062 and a second member 1064. Therefore, processing is easy. In this way, an external flowing water channel is not necessary and the manufacturing process can be simplified. In this embodiment, the fuel gas flow passages 1040a and 1060a correspond to gas passages, and the oxidant gas flow passages 1040b and 1060b correspond to air passages.

Next, the details of the cooling water manifold will be described based on FIG. 1 with reference to FIG. Here, the nth water flow passage is formed so as to flow the cooling water from the nth cooling water manifold to the (n+1)th cooling water manifold.

That is, in the first cooling water manifold 12, at least a partial region of each of the plurality of separators 104 and 106 on the first side surface 10 a of the stacked body 10 along the accumulation direction and the first water flow path 108 of the second separator 106. And one of the flow path ports in the. As a result, the first cooling water manifold 12 supplies the cooling water introduced from the cooling water inlet 122 to the laminated body 10 and one channel opening in the first water channel 108.

The second cooling water manifold 14 includes at least a partial region of each of the plurality of separators 104 and 106 on the second side face 10b that is the side face opposite to the first side face 10a, and the other flow passage port of the first water flow passage 108. And one of the flow path openings in the second water flow path 110 are covered. As a result, the second cooling water manifold 14 supplies the cooling water supplied via the first water flow path 108 to one of the flow path ports of the laminated body 10 and the second water flow path 110.

The third cooling water manifold 16 has at least a partial region of each of the plurality of separators 104 and 106 on the first side face 10a, the other flow passage port of the second water flow passage 110, and one flow passage of the third water flow passage 112. It covers the roadway. As a result, the third cooling water manifold 16 supplies the cooling water supplied via the second water flow passage 110 to one of the flow passage ports of the laminated body 10 and the third water flow passage 112.

The fourth cooling water manifold 18 includes at least a partial region of each of the plurality of separators 104 and 106 on the second side face 10b, the other flow passage port of the third water flow passage 112, and one flow passage of the fourth water flow passage 114. It covers the roadway. As a result, the fourth cooling water manifold 18 supplies the cooling water supplied via the third water flow passage 112 to one of the flow passage ports of the laminated body 10 and the fourth water flow passage 114.

The fifth cooling water manifold 20 includes at least a partial region of each of the plurality of separators 104 and 106 on the first side face 10a, the other flow passage port of the fourth water flow passage 114, and one flow passage of the fifth water flow passage 116. It covers the roadway. As a result, the fifth cooling water manifold 20 supplies the cooling water supplied through the fourth water flow passage 114 to one of the flow passage ports of the laminated body 10 and the fifth water flow passage 116.

The sixth cooling water manifold 22 covers at least a partial region of each of the plurality of separators 104 and 106 on the second side face 10b and the other flow passage port of the fifth water flow passage 116. As a result, the sixth cooling water manifold 22 supplies the cooling water supplied through the fifth water flow passage 116 to the stacked body 10 and guides the cooling water through the cooling water outlet 222.

As described above, the N water passage groups penetrating the second side surface 10b which is the side surface opposite to the first side surface 10a, where N is an integer of 2 or more, are formed in the separator 106. In this case, (N+1) cooling water manifolds are arranged on the side surfaces 10 a and 10 b of the stacked body 10. Then, the cooling water is sequentially supplied to each of the (N+1) cooling water manifolds, and the cooling water introduced into the n-th (n is an integer from 1 to N) cooling water manifold is the bottom of the separator 106. Is introduced into the (n+1)th cooling water manifold through the nth water flow channel group, and is supplied to the outside of the fuel cell stack 1 from the (N+1)th cooling water manifold. For example, if N=2, the cooling water is discharged to the outside of the fuel cell stack 1 from the third cooling water manifold.

Further, the side surfaces of the separators 104 and 106 come into contact with the cooling water only at the locations facing the cooling water manifolds 12, 14, 16, 18, 20, and 22. Therefore, the areas of the cooling water manifolds 12, 14, 16, 18, 20, 22 increase the contact area with the side surfaces of the separators 104, 106, and thus the cooling water can be supplied more efficiently if the area is made as large as possible. is there.

In addition, in FIG. 1, the cooling water manifolds are arranged at three places on the left and right. However, the number of cooling water manifolds may be 3 or more in total, and is not limited to 6 in FIG.

Next, the details of the fuel gas manifolds 24 and 26 will be described based on FIG. 1 with reference to FIGS. 4 and 5. The first fuel gas manifold 24 communicates with the fuel gas flow passages 1040a and 1060a formed in the separators 104 and 106 of the laminated body 10, respectively. That is, the first fuel gas manifold 24 supplies the fuel gas containing hydrogen to the fuel electrode 102e of each of the fuel cells 102 via the fuel gas flow passages 1040a and 1060a.

The second fuel gas manifold 26 communicates with the fuel gas flow passages 1040a and 1060a formed in each of the separators of the stacked body 10. That is, the second fuel gas manifold 26 discharges, from the gas supplied to the fuel electrode 102e of each of the fuel cells 102, a gas not consumed by the electrochemical reaction from the fuel gas outlet 262.

Next, the details of the air gas manifolds 28 and 30 will be described based on FIG. 1 with reference to FIGS. 4 and 5. The first air gas manifold 28 communicates with the oxidant gas flow passages 1040b and 1060b formed in the separators 104 and 106 of the stack 10. That is, the first air gas manifold 28 supplies air to the oxidant electrode 102d of each of the fuel cells 102 via the oxidant gas flow passages 1040b and 1060b.

The second air gas manifold 30 communicates with the oxidant gas flow passages 1040b and 1060b formed in the separators 104 and 106 of the laminated body 10, respectively. That is, the second fuel gas manifold 26 discharges, from the air supplied to the oxidant electrode 102d of each of the fuel cells 102, air not consumed by the electrochemical reaction from the air gas outlet 302.

As described above, the first fuel gas manifold 24 and the second air gas manifold 30 are arranged on the third side surface 10c of the side surfaces of the stacked body 10 along the horizontal direction. Further, the second fuel gas manifold 26 and the first air gas manifold are arranged on the fourth side face 10d, which is the side face opposite to the third side face 10c. That is, a total of four chambers are required as chambers for the inlet and outlet of fuel gas and air, and two chambers are provided for each of the pair of manifolds arranged on the opposite surfaces. The combination of the inlet and outlet of the fuel gas and the air arranged in each of the two chambers of the pair of manifolds can be selected according to the cell characteristics of the fuel cell unit 102.

The above is the description of the configuration of the fuel cell stack 1. Next, the flow of cooling water will be described with reference to FIGS. 1 and 5.

First, the cooling water introduced from the cooling water inlet 122 before the start of the operation is introduced into the first cooling water manifold 12, and the air in the first cooling water manifold 12 is passed through the first water flow path 108. The second separator 106 is extruded. Subsequently, the cooling water supplied through the first water flow passage 108 pushes out the air in the second cooling water manifold 14 through the second water flow passage 110 to the third cooling water manifold 16. In this way, the air in the fourth cooling water manifold 18, the fifth cooling water manifold 20, and the sixth cooling water manifold 22 is pushed out in order, and all the cooling water manifolds are filled with cooling water. It

Next, during normal operation, with all the cooling water manifolds filled with cooling water, the cooling water introduced into the first cooling water manifold 12 alternately passes through the water flow paths and the cooling water manifolds. And is discharged from the cooling water outlet 222 arranged in the sixth cooling water manifold 22. That is, the cooling water flows in an upward flow from the cooling water inlet 122 arranged at the lowermost portion toward the cooling water outlet 222 arranged at the uppermost portion. In this case, fuel gas or air may mix into the water flow path through the pores of the separator. At this time, since the gas is flowing upward in the water flow path, the gas is also sequentially pushed upward and discharged from the cooling water outlet 222. In this way, the accumulated gas is discharged as it is along with the cooling water according to the upward flow of the cooling water. On the other hand, in the case of the downward flow, the gas accumulated in the uppermost cooling water manifold may hinder the flow of the cooling water. However, since the flow of the cooling water according to the present embodiment is an upward flow, the flow water flow obstruction is further reduced.

On the other hand, the cooling water other than the water supplied to the fuel cell 102 from the side surfaces of the separators 104 and 106, that is, the extra cooling water needs to be discharged to the outside of the stacked body 10. Therefore, at least one sheet of the second separator 106 having the water flow path needs to be arranged in the laminated body 10. Further, as described above, the cooling water passing through the water flow path formed in the second separator 106 also has a role of cooling the heat generated by the electrochemical reaction in the fuel cell unit. That is, by disposing the second separator 106 at a position where it is necessary to cool more strongly, it is possible to drain excess cooling water and perform more efficient cooling. The number of the second separators 106 can be determined according to the cooling performance.

As described above, according to the fuel cell stack 1 according to the present embodiment, the laminated body 10 is configured using the second separator 106 in which the water flow path is formed. Therefore, it is possible to drain the excess cooling water and stack the second separator 106 at a position where it is necessary to cool more strongly, and it is possible to perform more efficient cooling. Furthermore, since the cooling water is supplied to the laminated body 10 in an upward flow through the water passages 108 to 116 of the second separator 106, it is possible to prevent the running water from being obstructed by the fuel gas or air mixed in the water passages 108 to 116. It can be reduced.

(Second embodiment)
The water flow path of the second separator according to the first embodiment is configured by one, whereas the water flow path of the second separator according to the second embodiment is configured by a plurality of water flow path groups. Differences from the first embodiment will be described below.

The water channel of the second separator 106 according to the second embodiment will be described based on FIG. 6. FIG. 6 is a schematic view showing a cross section of the cooling water manifold and a water flow path group formed on one surface of the second member 1064. The first water channel 108 is composed of a first water channel group 108n which is a plurality of channels. That is, the first water channel group 108n is configured by a plurality of parallel linear channels. Similarly, the second water flow channel 110 is configured by a second water flow channel group 110n that is a plurality of water channels, and the third water flow channel 112 is configured by a third water flow channel group 112n that is a plurality of water channels. The 4th water channel 114 is composed of a fourth water channel group 114n which is a plurality of water channels, and the fifth water channel 116 is composed of a fifth water channel group 116n which is a plurality of water channels. The first water flow channel group 108n is located at the bottom, and the second water flow channel group 110n is located thereon. The fifth water channel group 116n is arranged in this order. That is, the water channel of the nth group is formed so as to connect the nth cooling water manifold and the (n+1)th cooling water manifold.

As a result, the cooling water introduced into the first cooling water manifold 12 is introduced into the second cooling water manifold 14 via the first water flow channel group 108n. Further, it is introduced into the third cooling water manifold 16 through the second water flow channel group 110n, and finally discharged from the sixth cooling water manifold 22. That is, the cooling water is an upward flow, and as described above, it is possible to further reduce the flow water obstruction caused by the fuel gas or air mixed in the water flow path group n.

In this way, the water flow paths 108, 110, 112, 114, 116 are respectively configured by the water flow path groups 108n, 110n, 112n, 114n, 116n. Therefore, the area where the cooling water flowing through the second separator 106 contacts the second separator 106 is further increased. As a result, the cooling capacity of the second separator 106 is further improved, and the discharging capacity of the cooling water is also improved. Although the cooling water manifolds are arranged at six places, the configuration is not limited to this.

As described above, according to the fuel cell stack 1 according to the present embodiment, the water flow path of the second separator 106 is configured by the water flow path groups 108n to 116n that are a plurality of water paths. Therefore, the second separator 106 can discharge more cooling water and cool more efficiently. Furthermore, since the cooling water is supplied to the laminated body 10 in an ascending flow through the water flow passage groups 108n to 116n of the second separator 106, it is possible to further reduce the flow water obstruction due to the fuel gas or the air mixed in the water flow passage. ..

Although all the water flow paths of the second separator 106 described above are configured to be linear, at least one of the water flow paths of the second separator 106 may be formed in the crank-shaped water path 118 as shown in FIG. 7. Thereby, the position of the other path opening can be configured above the position of the one path opening.

Although some embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modified examples are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

1: Fuel cell stack, 10: Laminated body, 12: First cooling water manifold, 14: Second cooling water manifold, 16: Third cooling water manifold, 18; Fourth cooling water manifold, 20: Fourth 5, cooling water manifold 22, 22: sixth cooling water manifold, 24: first fuel gas manifold, 26: second fuel gas manifold, 28: first air manifold, 30: second air manifold, 108 : First water flow channel, 110: Second water flow channel, 112: Third water flow channel, 114: Fourth water flow channel, 116: Fifth water flow channel, 108n: First water flow channel group, 110n: Second water flow channel Group, 112n: third water flow channel group, 114n: fourth water flow channel group, 116n: fifth water flow channel group

Claims (4)

A fuel cell and a separator made of a porous material are a laminated body in which a plurality of layers are alternately laminated, and at least one of the separators is the first side surface along the laminating direction of the laminated body. A laminated body, which is a separator in which N water passage groups penetrating a second side surface which is a side surface opposite to the first side surface, where N is an integer of 2 or more,
A coolant manifold disposed on the second side and the first side surface, together with the second side surface and said first side (N + 1) pieces of cooling water manifold,
A fuel cell stack comprising :
The n- th (n is an integer from 1 to N) water passage of the N water passage groups is opened to the n- th cooling water manifold and the (n+1) -th cooling water manifold,
Wherein the n (n is from 1 N integer) in said cooling water introduced into the second cooling water manifold through said n-th water flow path having the said separator (n + 1) th cooling water manifold Is introduced and discharged from the (N+1)th cooling water manifold to the outside of the stack ,
The 1st coolant manifold located at the bottom of the fuel cell stack, wherein the (N + 1) th cooling water manifold is positioned at the top, the fuel cell stack. The fuel cell and the separator have a rectangular shape,
The fuel cell has a fuel electrode formed on one main surface of the electrolyte membrane and an air electrode formed on the other main surface,
The separator has a gas passage for a fuel electrode formed on one main surface and an air passage for an air electrode formed on the other main surface,
Wherein the separator water flow path is formed, further wherein the first side and the second side surface and the fuel cell stack of the mounting serial to請Motomeko 1 in which a plurality of water flow paths are formed to penetrate the between the main surface. A fuel gas manifold for introducing a fuel gas into each of the plurality of fuel cells via the gas passage,
Further comprising an air manifold for introducing air into each of the plurality of fuel cells through the air passage,
The fuel gas manifold and the air manifold, in claim 2, which is disposed in each fourth side is a side opposite the third side surface and the third side of the side surfaces along the horizontal direction of the laminate The described fuel cell stack. Separator formed of said water flow passage, the fuel cell stack according to claim 1乃Optimum 3 Neu deviation or claim that is formed in two parts.

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