JP2017126472A - Fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel battery that is miniaturized and prevented from being short-circuited between laminates.SOLUTION: A fuel battery includes a first power generator that generates electric power using oxidant gas and fuel gas and is stacked over plural layers, a second power generator that generates electric power using oxidant gas and fuel gas and is stacked over plural layers to be adjacent to the first power generator, and an insulating portion for insulating the first power generator and the second power generator from each other. The insulating portion includes a manifold penetrating in the stacking direction of the first power generator and the second power generator, a first discharge path for discharging one of the oxidant gas and the fuel gas used for power generation from the first power generator to the manifold, and a second discharge path for discharging the one gas from the second power generator to the manifold. The first discharge path and the second discharge path are provided in the insulating portion such that lines extending in the respective discharge directions do not intersect each other in the manifold.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a fuel cell.

  As a new vehicle different from a gasoline vehicle, a fuel cell vehicle (FCV) equipped with a fuel cell attracts attention. The fuel cell mounted on the FCV drives the motor by generating electricity by chemically reacting hydrogen of fuel and oxygen in the air.

  A fuel cell is configured as a stack (so-called stack) in which a plurality of fuel cells are stacked, and the plurality of stacks may be used for power generation (see, for example, Patent Documents 1 to 3). For example, when two identical laminates are electrically connected in series, an output voltage twice as high as the output voltage of each laminate can be obtained from the fuel cell, and the output current can be halved. There is an advantage that loss is reduced.

JP 2005-216783 A JP-A-2005-332673 JP-A-5-307968

  However, when a plurality of laminated bodies are used for power generation, it is necessary to prevent a short circuit between the laminated bodies. When the two stacked bodies are electrically connected in series, a potential difference corresponding to twice the output voltage from the output voltage of each stacked body is generated between the fuel cells in each stacked body.

  For this reason, when a short circuit occurs between the laminates, not only the power generation performance of the laminate is lowered, but also the material around the laminate may be damaged by electrolysis or heat. This is the same because there is a potential difference between the fuel cells in each stack even when the two stacks are not electrically connected in series.

  In order to prevent a short circuit between the stacked bodies, for example, it is conceivable to sufficiently separate the stacked bodies to ensure insulation, but there is a problem that the fuel cell is enlarged. Further, since a manifold for supplying and discharging hydrogen or the like is required for each stacked body, the fuel cell is further increased in size. This problem is not limited to the fuel cell used for FCV, but also exists for fuel cells for other uses.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel cell that is prevented from being short-circuited between stacked bodies and miniaturized.

  The fuel cell described in the present specification generates power using an oxidizing gas and a fuel gas, and generates a first power generation unit stacked over a plurality of layers, and generates a power using an oxidizing gas and a fuel gas, and the first power generation over a plurality of layers. A second power generation unit stacked adjacent to the power generation unit; and an insulating unit that insulates between the first power generation unit and the second power generation unit, wherein the insulation unit includes the first power generation unit and the first power generation unit. A manifold penetrating in the stacking direction of the second power generation unit; a first discharge path for discharging one of the oxidizing gas and the fuel gas used for power generation from the first power generation unit to the manifold; and A second discharge path for discharging one gas from the second power generation unit to the manifold is provided, and the first discharge path and the second discharge path have lines extending in the respective discharge directions in the manifold. Provided in the insulation so as not to intersect It has been.

  According to the present invention, a short circuit between stacked bodies can be prevented and the fuel cell can be downsized.

It is a perspective view which shows the fuel cell of a comparative example. It is a disassembled perspective view of the fuel cell of a comparative example. It is a figure which shows a mode that air is supplied to the fuel cell of a comparative example. It is a perspective view which shows the fuel cell of an Example. It is a disassembled perspective view of the fuel cell of an Example. It is a figure which shows a mode that air is supplied to the fuel cell of an Example. It is a top view which shows the comparative example of an intermediate | middle insulation part. It is a top view which shows an example of an intermediate | middle insulating part. It is a top view which shows the other example of an intermediate | middle insulating part. It is a top view which shows the other example of an intermediate | middle insulating part.

  FIG. 1 is a perspective view showing a fuel cell of a comparative example. FIG. 2 is an exploded perspective view of a fuel cell of a comparative example. In FIGS. 1 and 2, the right direction on the paper surface is the positive direction of the x axis, the oblique back direction of the paper surface is the positive direction of the y axis, and the upward direction of the paper surface is the positive direction of the z axis. The definition of the coordinate system is the same in the following drawings.

  The fuel cell 9a is a solid polymer fuel cell that generates electric power by receiving supply of air as an oxidizing gas and hydrogen gas as a fuel gas, and has a stacked structure in which a plurality of fuel cells 4a are stacked. In this example, the air-cooled fuel cell 9a is mentioned, but the water-cooled fuel cell has the same configuration except for the configuration of the manifold.

  The fuel cell 4 a includes a cathode separator 12, a membrane electrode gas diffusion layer assembly (MEGA) 22, and an anode separator 39. The MEGA 22 is sandwiched between a cathode side separator 12 and an anode side separator 39 which are plate-like members.

  The MEGA 22 receives supply of air from the plurality of air flow paths 120 formed on the surface of the cathode separator 12 facing the MEGA 22, and the plurality of hydrogen flow paths 32 formed on the surface of the anode separator 39 facing the MEGA 22. Hydrogen gas is supplied from The MEGA 22 generates electricity by an electrochemical reaction of oxygen and hydrogen gas in the air.

  Reference symbol P denotes a cross section of the MEGA 22. The MEGA 22 includes an electrolyte membrane 220, an anode electrode 221, a cathode electrode 222, and a gas diffusion layer 223. The electrolyte membrane 220 is made of, for example, an ion exchange resin membrane that exhibits good proton conductivity in a wet state. Examples of such ion exchange resin membranes include fluororesin-based membranes having sulfonic acid groups as ion exchange groups, such as Nafion (registered trademark).

  The electrolyte membrane 220 is sandwiched between the anode electrode 221 and the cathode electrode 222, and a portion constituted by the electrolyte membrane 220, the anode electrode 221 and the cathode electrode 222 is called an MEA (MEA: Membrane Electrode Assembly). Each of the anode electrode 221 and the cathode electrode 222 is a catalyst electrode layer, and is formed as a porous layer having gas diffusibility and composed of catalyst-supporting conductive particles. For example, the anode electrode 221 and the cathode electrode 222 are formed as a dry coating film of a catalyst ink that is a dispersion solution of platinum-supporting carbon.

  Gas diffusion layers 223 are laminated on the outside of the anode electrode 221 and the cathode electrode 222, respectively. The gas diffusion layer 223 has a function of allowing oxygen and hydrogen gas to reach the surfaces of the anode electrode 221 and the cathode electrode 222, and a function as a conductive path between the anode side separator 39 and the cathode side separator 12, respectively. The gas diffusion layer 223 includes a fiber base material such as carbon fiber, a flow path member obtained by processing a metal plate such as so-called expanded metal, and a porous member such as foam metal.

  Insulating seal portions 20 and 21 that are gas sealing insulating members are provided around the MEGA 22. The insulating seal portions 20 and 21 cover the outer peripheral end of the MEGA 22 over the entire circumference. The insulating seal portions 20 and 21 may be formed by, for example, injection molding of a resin member, or may be formed by bonding a plurality of resin film members.

  FIG. 2 shows only the insulating seal portions 20 and 21 at both ends in the x-axis direction. The insulating seal portion 20 at one end is provided with a through hole 200 penetrating in the stacking direction of the fuel cells 4a. The through hole 200 has a rectangular opening surface and supplies hydrogen gas to the fuel cell 9a. Functions as a part of the supply manifold 5a. The insulating seal portion 21 at the other end is provided with a through hole 210 that penetrates in the stacking direction of the fuel cells 4a. The through hole 210 discharges hydrogen gas used for power generation from the fuel cell 9a. It functions as a part of the manifold 6a.

  The cathode-side separator 12 is formed of a conductive material such as carbon or stainless steel, and has an uneven shape in the thickness direction (z-axis direction) formed by, for example, bending with a press die. The cathode separator 12 is provided with a plurality of parallel air flow paths 120 and 121 that are formed in an uneven shape in the thickness direction. The air flow paths 120 and 121 are provided on both surfaces of the cathode separator 12 in parallel with each other along the y-axis direction.

  One surface of the cathode-side separator 12 faces one surface of the MEGA 22, and the other surface of the cathode-side separator 12 faces one surface of the anode-side separator 39. The air flow path 120 provided on the opposing surface of the MEGA 22 guides the supplied air to the MEGA 22 and discharges air (oxygen) used for power generation by the MEGA 22 as indicated by arrows. The air flow path 120 and the air flow path 121 provided on the facing surface of the anode separator 39 cool the entire fuel cell 9a by passing air from the air supply port to the air discharge port.

  FIG. 3 shows how air is supplied to the fuel cell 9a of the comparative example. An example of the air supply means is a fan F. The fuel cell 9a and the fan F are installed facing each other.

  In the fuel cell 9a, the wind generated by the fan F is blown from the air supply port through the air flow paths 120 and 121 to the air discharge port as indicated by the arrows, thereby cooling the heat generated by power generation or the like. Then, oxygen is supplied to the MEGA 22. Thus, since the fuel cell 9a performs cooling using the air cooling method, not only the cooling water manifold necessary for supplying cooling water but also the air manifold necessary for supplying air can be omitted in the water cooling method.

  Referring to FIGS. 1 and 2 again, insulating seal portions 10 and 11 are provided at both ends of the cathode separator 12 in the x-axis direction. The insulating seal parts 10 and 11 are insulating members having gas sealing properties, like the insulating seal parts 20 and 21 of the MEGA 22. The insulating seal portions 10 and 11 insulate the cathode separator 12 from the outside of the fuel cell 9a and ensure airtightness.

  The insulating seal portion 10 at one end is provided with a through hole 100 penetrating in the stacking direction of the fuel cells 4a. The through hole 100 has a rectangular opening and supplies hydrogen gas to the fuel cell 9a. Functions as a part of the supply manifold 5a. The insulating seal 11 at the other end is provided with a through hole 101 that penetrates in the stacking direction of the fuel cells 4a. The through hole 101 discharges hydrogen gas used for power generation from the fuel cell 9a. It functions as a part of the manifold 6a.

  The anode-side separator 39 is made of a conductive material such as carbon or stainless steel, and has through holes 30 and 31 provided at both ends in the x-axis direction, and a hydrogen channel 32 formed on a surface facing the MEGA 22. . The hydrogen flow path 32 connects the through holes 30 and 31 to each other, guides the hydrogen gas supplied from the through hole 30 to the MEGA 22, and uses the hydrogen gas used for power generation by the MEGA 22 and water generated by the power generation through the through holes 31. Lead to.

  One through hole 30 has a rectangular opening surface, and overlaps with the through hole 200 of the insulating seal part 20 adjacent to the MEGA 22 and the through hole 100 of the insulating seal part 10 adjacent to the cathode side separator 12. Thus, the through holes 30, 100, 200 for all the stacked fuel cells 4a constitute a supply manifold 5a for supplying hydrogen gas from the outside of the fuel cell 9a, as shown in FIG.

  The other through hole 31 has a rectangular opening surface and overlaps with the through hole 210 of the insulating seal portion 21 adjacent to the MEGA 22 and the through hole 101 of the insulating seal portion 11 adjacent to the cathode separator 12. For this reason, as shown in FIG. 1, the through holes 31, 101, 210 are stacked by the number of stacked fuel cells 4a, thereby forming a discharge manifold 6a that discharges hydrogen gas to the outside of the fuel cell 9a. To do.

  The supply manifold 5a and the discharge manifold 6a are through holes provided along the stacking direction of the fuel cells 4a. Hydrogen gas is introduced into the supply manifold 5a from the hydrogen supply port 7a at the bottom of the fuel cell 9a, and circulates as indicated by reference numeral D1. The hydrogen supply port 7a corresponds to, for example, the lowermost through hole 100 of the stack of fuel cells 9a.

  Part of the hydrogen gas introduced into the supply manifold 5a is introduced into each anode-side separator 39 in the stack, is discharged to the discharge manifold 6a through the hydrogen flow path 32, and as shown by the symbol D2, the fuel cell 9a. Is exhausted to the outside through the hydrogen discharge port 8a at the lower part. A part of the water generated by the electrochemical reaction between hydrogen gas and oxygen is also discharged to the discharge manifold 6a through the hydrogen flow path 32. The hydrogen discharge port 8a corresponds to, for example, the lowermost through hole 101 of the stacked body of the fuel cell 9a.

  The hydrogen flow path 32 is, for example, a groove formed by press working or the like. As an example, the surface of the anode separator 39 is divided into three rows from the through hole 30 on the inlet side, and the through hole 31 on the outlet side while meandering. (See arrow). The hydrogen flow path 32 may be formed as a plurality of parallel grooves, but for convenience, it is drawn with a single line in FIG.

  The anode-side separator 39 of each fuel cell 4a is in contact with the cathode-side separator 12 of the fuel cell 4a immediately below, except for the bottom layer. Accordingly, since the fuel cells 4a are electrically connected in series with each other in the stack of the fuel cells 9a, the output voltage of the fuel cells 9a is the sum of the voltages of the fuel cells 4a.

  In this example, the fuel cell 9a is configured as a single stacked body. For example, when the fuel cell 9a is divided into two stacked bodies and the stacked bodies are electrically connected in series, the anode electrode 221 and the cathode Since the area of the electrode 222 is approximately halved, the output voltage can be increased approximately twice and the output current can be approximately halved while maintaining the obtained power. Thereby, the advantage that the resistance loss of a laminated body is reduced is acquired.

  However, when the fuel cell 9a is composed of a plurality of laminated bodies, it is conceivable to secure insulation by sufficiently separating the laminated bodies in order to prevent a short circuit between the laminated bodies, but the fuel cell becomes larger. . Further, if the supply manifold 5a and the discharge manifold 6a are provided for each stacked body, the fuel cell is further increased in size.

  Therefore, in the fuel cell according to the embodiment, by providing an insulating portion in which a supply manifold and a discharge manifold for hydrogen gas are formed between two stacked bodies, insulation between the stacked bodies is ensured and a supply manifold is provided. And the discharge manifold is shared between the laminates. In addition, in order to prevent short circuit between the stacked bodies caused by contact between the generated water discharged from each stacked body together with hydrogen gas to the discharge manifold, lines extending in the discharge direction of the generated water intersect in the discharge manifold. In order to prevent this, a discharge path is provided in the insulating part. Thereby, even when the fuel cell is composed of two laminated bodies, the fuel cell can be downsized. The fuel cell of an Example is demonstrated below.

  FIG. 4 is a perspective view showing the fuel cell of the embodiment. FIG. 5 is an exploded perspective view of the fuel cell of the embodiment.

  The fuel cell 9 is a polymer electrolyte fuel cell that generates electric power by receiving supply of air as an oxidizing gas and hydrogen gas as a fuel gas. The fuel cell 9 includes a stack STa in which a plurality of fuel cells 40 are stacked, a stack STb in which a plurality of fuel cells 41 are stacked, and an insulating portion ZT that insulates between the two stacks STa and STb. Have. In addition, although the fuel cell 9 of this example is comprised from two laminated body STa, STb, there is no limitation in the number of laminated bodies. In this example, the air-cooled fuel cell 9 is used, but the water-cooled fuel cell has the same configuration except for the configuration of the manifold.

  The fuel cell 40 includes a cathode side separator 140, a MEGA 250, and an anode side separator 330. The MEGA 250 is sandwiched between a cathode-side separator 140 and an anode-side separator 330 that are plate-like members. The fuel battery cell 40 is an example of a first power generation unit, is stacked over a plurality of layers, and generates power using air and hydrogen gas.

  The fuel cell 41 includes a cathode side separator 141, a MEGA 251, and an anode side separator 331. The MEGA 251 is sandwiched between a cathode side separator 141 and an anode side separator 331 which are plate-like members. The fuel battery cell 41 is an example of a second power generation unit, is stacked adjacent to the other fuel battery cell 40 over a plurality of layers, and generates power using air and hydrogen gas.

  The MEGAs 250 and 251 have the same configuration as the MEGA 22 of the fuel cell 9a of the comparative example. The MEGA 250 receives supply of air from the plurality of air flow paths 160 formed on the surface of the cathode separator 140 facing the MEGA 250, and the plurality of hydrogen flow paths 340 formed on the surface of the anode separator 330 facing the MEGA 250. Hydrogen gas is supplied from

  The MEGA 251 receives supply of air from the plurality of air flow paths 170 formed on the surface facing the MEGA 251 of the cathode side separator 141, and the plurality of hydrogen flow paths 341 formed on the surface facing the MEGA 251 of the anode side separator 331. Hydrogen gas is supplied from The MEGAs 250 and 251 generate power by an electrochemical reaction of oxygen and hydrogen gas in the air.

  Around the MEGA 250 and 251, an insulating seal portion 23, which is an insulating member having a gas sealing property, is provided. The insulating seal part 23 covers the outer peripheral ends of the MEGAs 250 and 251 over the entire circumference. For example, the insulating seal portion 23 may be formed by injection molding of a resin member, or may be formed by bonding a plurality of resin film members. In FIG. 5, only the insulating seal portions 23 at both ends in the x-axis direction are shown.

  Further, an intermediate insulating portion 24 that is an insulating member having a gas sealing property is provided between the MEGAs 250 and 251. The intermediate insulating portion 24 is formed of a resin-based material, similar to the insulating seal portion 23 described above. The intermediate insulating part 24 insulates and seals between the MEGAs 250 and 251. The intermediate insulating portion 24 may be molded integrally with the insulating seal portion 23 or may be molded individually.

  The intermediate insulating portion 24 is provided with through holes 240 and 241 that penetrate in the stacking direction of the fuel cells 40 and 41. The through hole 241 has a rectangular opening surface, and functions as a part of the supply manifold 5 that supplies hydrogen gas to the fuel cell 9. The through hole 240 functions as a part of the discharge manifold 6 that discharges the hydrogen gas used for power generation from the fuel cell 9.

  The cathode-side separators 140 and 141 are formed of a conductive material such as carbon or stainless steel, as in the cathode-side separator 12 of the fuel cell 9a of the comparative example, and are formed in a thickness direction (z (Axial direction). The cathode-side separators 140 and 141 are provided with a plurality of parallel air flow paths 160, 161, 170, and 171 that are formed in an uneven shape in the thickness direction. The air flow paths 160, 161, 170, and 171 are provided on both surfaces of the cathode separators 140 and 141 in parallel with each other along the y-axis direction.

  One surface of the cathode-side separator 140 faces one surface of the MEGA 250, and the other surface of the cathode-side separator 140 faces one surface of the anode-side separator 330. The air flow path 160 provided on the opposite surface of the MEGA 250 is generated by an electrochemical reaction with the air (oxygen) used for power generation by the MEGA 250 while guiding the supplied air to the MEGA 250 as indicated by arrows. Drain some of the water. The air flow path 161 and the air flow path 161 provided on the opposing surface of the anode-side separator 330 cool the entire fuel cell 9 by passing air from the air supply port to the air discharge port.

  One surface of the cathode side separator 141 is opposed to one surface of the MEGA 251, and the other surface of the cathode side separator 141 is opposed to one surface of the anode side separator 331. The air flow path 170 provided on the opposite surface of the MEGA 251 is generated by an electrochemical reaction with air (oxygen) used for power generation by the MEGA 251 while guiding the supplied air to the MEGA 251 as indicated by arrows. Drain some of the water. Further, the air flow path 171 provided on the opposed surface of the air flow path 170 and the anode side separator 331 cools the entire fuel cell 9 by passing air from the air supply port to the air discharge port.

  FIG. 6 shows how air is supplied to the fuel cell 9 of the embodiment. Air is supplied from the fan F to the fuel cell 9 as in the comparative example. The fuel cell 9 and the fan F are installed facing each other.

  In the fuel cell 9, the wind generated by the fan F is generated by power generation or the like by blowing from the air supply port to the air discharge port through the air flow paths 160, 161, 170, 171 as indicated by arrows. The heat is cooled and the oxygen is supplied to the MEGAs 250 and 251. Thus, since the fuel cell 9 performs cooling using the air cooling system, not only the cooling water manifold necessary for supplying the cooling water but also the air manifold necessary for supplying the air can be omitted in the water cooling system.

  4 and 5 again, the insulating seal portion 13 is provided at one end of the cathode side separator 140 and one end of the cathode side separator 141 in the x-axis direction. The insulating seal portion 13 is an insulating member having a gas sealing property, similar to the insulating seal portion 23 of the MEGAs 250 and 251. The insulating seal portion 13 insulates the cathode separators 140 and 141 from the outside of the fuel cell 9 and ensures airtightness.

  Further, an intermediate insulating portion 15 that is an insulating member having a gas sealing property is provided between the other ends of the cathode separators 140 and 141. The intermediate insulating portion 15 is formed of a resin-based material in the same manner as the insulating seal portion 13 described above. The intermediate insulating portion 15 insulates and seals between the cathode side separators 140 and 141.

  The intermediate insulating portion 15 is provided with through holes 150 and 151 penetrating in the stacking direction of the fuel cells 40 and 41. The through hole 151 has a rectangular opening surface, and functions as a part of the supply manifold 5 that supplies hydrogen gas to the fuel cell 9. Further, the through hole 150 functions as a part of the discharge manifold 6 that discharges the hydrogen gas used for power generation from the fuel cell 9.

  The anode-side separator 330 is formed of a conductive material such as carbon or stainless steel, and has a hydrogen flow path 340 formed on a surface facing the MEGA 250. The anode separator 331 is formed of a conductive material such as carbon or stainless steel, and has a hydrogen flow path 341 formed on a surface facing the MEGA 251.

  Between the anode-side separators 330 and 331, an intermediate insulating portion 35 that is an insulating member having a gas sealing property is provided. The intermediate insulating portion 35 is formed of a resin-based material, similar to the intermediate insulating portions 15 and 24 described above. The intermediate insulating portion 35 insulates and seals between the anode side separators 330 and 331.

  The intermediate insulating portion 35 is provided with through holes 350 and 351 penetrating in the stacking direction of the fuel cells 40 and 41. The through hole 351 has a rectangular opening surface and functions as a part of the supply manifold 5 that supplies hydrogen gas to the fuel cell 9. Further, the through hole 350 functions as a part of the discharge manifold 6 that discharges the hydrogen gas used for power generation from the fuel cell 9.

  The hydrogen flow path 340 of the anode-side separator 330 guides the hydrogen gas supplied from the through hole 351 to the MEGA 250 and guides the hydrogen gas used for power generation by the MEGA 250 and the water generated by the power generation to the through hole 350. The hydrogen channel 341 of the anode separator 331 guides the hydrogen gas supplied from the through hole 351 to the MEGA 251 and guides the hydrogen gas used for power generation by the MEGA 251 and the water generated by the power generation to the through hole 350. . The intermediate insulating portion 35 is formed with hydrogen gas flow paths connecting the hydrogen flow paths 340 and 341 and the through holes 350 and 351.

  The intermediate insulating part 35 between the anode side separators 330 and 331, the intermediate insulating part 15 between the cathode side separators 140 and 141, and the intermediate insulating part 24 between the MEGAs 250 and 251 are the fuel cell 40 and 41, respectively. By stacking as many as the number of stacked layers, the insulating portion ZT between the stacked bodies STa and STb shown in FIG. 4 is configured.

  One through hole 351 has a rectangular opening surface and overlaps with the through hole 241 of the intermediate insulating part 24 and the through hole 151 of the intermediate insulating part 15. Therefore, as shown in FIG. 4, the supply holes 5, 151, and 351 are stacked by the number of stacked fuel cells 40 and 41 to supply hydrogen gas from the outside of the fuel cell 9. Configure.

  The other through hole 350 has a rectangular opening surface and overlaps with the through hole 240 of the intermediate insulating part 24 and the through hole 150 of the intermediate insulating part 15. Therefore, as shown in FIG. 4, the exhaust holes 6, 150, and 350 are stacked by the number of stacked fuel cells 40 and 41 to discharge hydrogen gas to the outside of the fuel cell 9. Configure. The discharge manifold 6 is an example of a manifold.

  The supply manifold 5 and the discharge manifold 6 are through holes provided along the stacking direction of the fuel cells 40 and 41. Hydrogen gas is introduced into the supply manifold 5 from the hydrogen supply port 7 at the bottom of the fuel cell 9 and flows as indicated by reference numeral D3. The hydrogen supply port 7 corresponds to, for example, the lowermost through hole 151 of the stack of fuel cells 9.

  Part of the hydrogen gas introduced into the supply manifold 5 is introduced into the anode-side separators 330 and 331 in the stacked bodies STa and STb, discharged through the hydrogen flow paths 340 and 341 to the discharge manifold 6, and reference numeral D4. As shown in FIG. 5, the fuel cell 9 is exhausted to the outside through the hydrogen discharge port 8 below. A part of the water generated by the electrochemical reaction between hydrogen gas and oxygen is also discharged to the discharge manifold 6 through the hydrogen flow paths 340 and 341. The hydrogen discharge port 8 corresponds to, for example, the lowermost through hole 150 of the stacked bodies STa and STb of the fuel cell 9.

  The hydrogen flow paths 340 and 341 are grooves formed by, for example, pressing. For example, the hydrogen flow path 340 is provided from the inlet-side through hole 351 toward the outlet-side through hole 350 while meandering the surface of the anode-side separator 330. Further, as an example, the hydrogen flow path 341 is provided from the inlet-side through hole 351 toward the outlet-side through hole 350 while meandering the surface of the anode-side separator 331. In addition, although the hydrogen flow paths 340 and 341 are formed as a plurality of parallel grooves, they are drawn with a single line in FIG. 5 for convenience.

  In this example, the fuel cell 9 is composed of two stacked bodies STa and STb. For this reason, when the stacked bodies STa and STb are electrically connected in series, the area of the anode electrode 221 and the cathode electrode 222 is about half that of the comparative example, so that the output voltage is maintained while maintaining the obtained power. Can be increased by a factor of approximately 2 and the output current can be halved. Thereby, the advantage that the resistance loss of laminated body STa, STb is reduced is acquired. The stacked bodies STa and STb are not limited to this, and may be electrically connected in parallel.

  In addition, since the insulating portion ZT provided with the supply manifold 5 and the discharge manifold 6 is provided between the two stacked bodies STa and STb, insulation is ensured between the stacked bodies STa and STb. Since the supply manifold 5 and the discharge manifold 6 are shared, a seal member between the manifolds that is necessary when the manifold is divided becomes unnecessary, and the fuel cell 9 can be downsized. Moreover, since the length of the hydrogen flow paths 340 and 341 in the fuel cells 40 and 41 can be shortened as compared with the comparative example, the fuel cell 9 can be downsized by making the grooves of the hydrogen flow paths 340 and 341 shallow, for example. Is possible.

  However, as described below, the generated water that flows from the fuel cells 40 of the stacked body STa to the discharge manifold 6 and a part of the generated water that flows from the fuel cells 41 of the stacked body STb to the discharge manifold 6 are partly discharged. In the case where a crossed liquid bridge is formed, the fuel cells 40 and 41 are electrically connected and the insulation is lost.

  FIG. 7 is a top view showing a comparative example of the intermediate insulating portion 35. As described above, the intermediate insulating portion 35 is provided between the anode-side separators 330 and 331, and has the through-hole 351 constituting the supply manifold 5 and the through-hole 350 constituting the discharge manifold 6.

  The hydrogen flow path 340 and the through hole 351 of the anode separator 330 communicate with each other via a plurality of supply paths 370 formed on the surface of the intermediate insulating portion 35. As an example, the plurality of supply paths 370 are formed as a plurality of parallel grooves, but are not limited thereto. The hydrogen gas introduced from the supply manifold 5 enters the hydrogen flow path 340 through the supply path 370.

  Further, the hydrogen flow path 340 and the through hole 350 of the anode-side separator 330 communicate with each other via a plurality of discharge paths 360 c formed on the surface of the intermediate insulating portion 35. As an example, the plurality of discharge paths 360c are formed as a plurality of parallel grooves, but are not limited thereto. Part of the hydrogen gas used for power generation and the generated water generated by power generation is discharged to the discharge manifold 6 through the discharge path 360c. Here, the discharge direction of the discharge path 360c is indicated by the symbol Xa.

  On the other hand, the hydrogen channel 341 and the through hole 351 of the anode separator 331 communicate with each other through a plurality of supply channels 371 formed on the surface of the intermediate insulating portion 35. As an example, the plurality of supply paths 371 are formed as a plurality of parallel grooves, but are not limited thereto. The hydrogen gas introduced from the supply manifold 5 enters the hydrogen flow path 341 through the supply path 371.

  In addition, the hydrogen flow path 341 and the through hole 350 of the anode side separator 331 communicate with each other through a plurality of discharge paths 361 c formed on the surface of the intermediate insulating portion 35. The plurality of discharge paths 361c are formed as a plurality of parallel grooves as an example, but are not limited thereto. Part of the hydrogen gas used for power generation and the generated water generated by power generation is discharged to the discharge manifold 6 through the discharge path 361c. Here, the discharge direction of the discharge path 361c is indicated by the symbol Xb.

  In this example, as indicated by a dotted line, a line extending in the discharge direction Xa of the discharge path 360c and a line extending in the discharge direction Xb of the discharge path 361c intersect in the discharge manifold 6. Therefore, the generated water discharged from the discharge path 360c to the discharge manifold 6 and the generated water discharged from the discharge path 361c to the discharge manifold 6 come into contact with each other to form a liquid bridge between the anode side separators 330 and 331. May become conductive. When the anode side separators 330 and 331 are electrically connected, the stacked bodies STa and STb are short-circuited as described above.

  In contrast, a partition plate is provided in the discharge manifold 6 so that the generated water discharged from the discharge path 360c to the discharge manifold 6 and the generated water discharged from the discharge path 361c to the discharge manifold 6 do not come into contact with each other. You can also. However, in this case, since the surface area in the discharge manifold 6 increases by the surface integral of the partition plate, pressure loss due to the flow of hydrogen gas increases, which is not effective.

  Therefore, in the following embodiments, the discharge paths 360 c and 361 c are provided in the insulating portion ZT so that the lines extending in the discharge directions Xa and Xb do not intersect in the discharge manifold 6. Note that when the operating temperature range of the fuel cell 9 exceeds the temperature at which the generated water is vaporized, a liquid bridge of the generated water is not formed in the discharge manifold 6, so Even if the lines extending in the discharge directions Xa and Xb intersect in the discharge manifold 6, the stacked bodies STa and STb are not short-circuited.

  FIG. 8 is a top view illustrating an example of the intermediate insulating portion 35. In FIG. 8, the same components as those in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted.

  The intermediate insulating portion 35 is provided with through holes 350 and 351 and a plurality of discharge paths 360 and 361. The discharge path 360 is an example of a first discharge path, and discharges hydrogen gas from the MEGA 250 to the discharge manifold 6. The discharge path 361 is an example of a second discharge path, and discharges hydrogen gas from the MEGA 251 to the discharge manifold 6.

  The hydrogen flow path 340 and the through hole 350 of the anode side separator 330 communicate with each other via a plurality of discharge paths 360 formed on the surface of the intermediate insulating portion 35. The plurality of discharge paths 360 is formed as a plurality of parallel grooves as an example, but is not limited thereto. A part of the hydrogen gas used for power generation and the generated water generated by power generation is discharged to the discharge manifold 6 through the discharge path 360.

  Further, the hydrogen flow path 341 and the through hole 350 of the anode side separator 331 communicate with each other through a plurality of discharge paths 361 formed on the surface of the intermediate insulating portion 35. The plurality of discharge paths 361 are formed as a plurality of parallel grooves as an example, but are not limited thereto. A part of the hydrogen gas used for power generation and the generated water generated by power generation is discharged to the discharge manifold 6 through the discharge path 361.

  In this example, as indicated by a dotted line, the line extending in the discharge direction Xa of the discharge path 360 and the line extending in the discharge direction Xb of the discharge path 361 do not intersect within the discharge manifold 6. More specifically, the discharge paths 360 and 361 are provided so that the discharge directions Xa and Xb are parallel to each other.

  Therefore, since the generated water discharged from the discharge path 360 to the discharge manifold 6 and the generated water discharged from the discharge path 361 to the discharge manifold 6 do not come into contact with each other to form a liquid bridge, the stacked bodies STa, STb Can be prevented from being short-circuited.

  In this example, the discharge directions Xa and Xb of the discharge paths 360 and 361 are parallel, but the present invention is not limited to this.

  FIG. 9 is a top view showing another example of the intermediate insulating portion 35. In FIG. 9, the same components as those in FIG. 8 are denoted by the same reference numerals, and the description thereof is omitted.

  In this example, as indicated by a dotted line, the discharge direction Xa of the discharge path 360 is 90 degrees with respect to the wall surface of the discharge manifold 6 in the top view of the opening surface of the discharge manifold 6, whereas the discharge path 361. The discharge direction Xb makes an acute angle α with respect to the wall surface of the discharge manifold 6. For this reason, the discharge direction Xa of the discharge path 360 and the discharge direction Xb of the discharge path 361 are not parallel.

  However, the line extending in the discharge direction Xa of the discharge path 360 and the line extending in the discharge direction Xb of the discharge path 361 do not intersect in the discharge manifold 6. Therefore, in this example as well, as in the example of FIG. 8, a short circuit between the stacked bodies STa and STb is prevented.

  Further, when the angle of the discharge direction Xa with respect to the wall surface of the discharge manifold 6 is 90 degrees as in the discharge path 360 of the present example, even if the generated water rebounds on the wall surface of the discharge manifold 6, the angle at which the generated water rebounds on the wall surface. On the other hand, it can be controlled to be 90 degrees. Therefore, as described below, in the case of the discharge manifold 6 having a rectangular opening surface, the angle of the other discharge path 361 in the discharge direction Xa with respect to the wall surface of the discharge manifold 6 is set to 90 degrees, so that the wall bounces off the wall surface. Formation of a liquid bridge by generated water is prevented.

  FIG. 10 is a top view showing another example of the intermediate insulating portion 35. In FIG. 10, the same reference numerals are given to configurations common to FIG. 8, and the description thereof is omitted.

  In this example, as indicated by a dotted line, the discharge direction Xa of the discharge path 360 and the discharge direction Xb of the discharge path 361 are 90 degrees with respect to the wall surface of the discharge manifold 6 in the top view of the opening surface of the discharge manifold 6. Eggplant. For this reason, even if the generated water discharged from the discharge paths 360 and 361 bounces off the wall surface of the discharge manifold 6, the angle at which the generated water bounces back can be controlled to be 90 degrees with respect to the wall surface.

  Accordingly, when the generated water bounces off the wall of the discharge manifold 6 from the discharge passages 360 and 361, the bounce direction is parallel, so that a liquid bridge of generated water is not generated. Therefore, according to this example, a short circuit between the stacked bodies STa and STb can be more effectively prevented.

  In the fuel cell 9 of the present embodiment, the stacking directions of the stacked bodies STa and STb coincide with the vertical direction so that the generated water stays in the discharge manifold 6 and the anode-side separators 330 and 331 do not conduct. It is preferable to be used in such a state. In this case, since the discharge direction of the generated water in the discharge manifold 6 is the direction of gravity, the generated water is effectively discharged by the gas flow of the discharged hydrogen gas and gravity. Accordingly, retention of the generated water in the discharge manifold 6 is prevented.

  Further, the fuel cell 9 of the present embodiment is not limited to the air cooling method, and may be a water cooling method. In this case, in addition to the hydrogen gas supply manifold 5 and the discharge manifold 6, the fuel cell 9 is provided with a cooling water supply manifold and discharge manifold, and an air supply manifold and discharge manifold.

  At this time, similarly to the hydrogen gas supply manifold 5 and the discharge manifold 6, the air supply manifold and the discharge manifold can be provided in the insulating portion ZT and shared between the two stacked bodies STa and STb. . Further, a supply path and a discharge path similar to the hydrogen gas supply paths 370 and 371 and the discharge paths 360 and 361 are provided in the intermediate insulating portion 15 between the cathode separators 140 and 141, respectively. It is possible to prevent a short circuit between the stacked bodies STa and STb due to the generation of.

  As described above, in the embodiment, the fuel cell 9 generates power using air and hydrogen gas, and generates fuel cells 40 stacked over a plurality of layers, and generates power using air and hydrogen gas, over a plurality of layers. A fuel battery cell 41 stacked adjacent to the fuel battery cell 40 and an insulating part ZT that insulates between the fuel battery cells 40 and 41 are provided.

  The insulating part ZT is used for power generation, a discharge manifold 6 penetrating in the stacking direction of the fuel cells 40, 41, a discharge path 360 for discharging hydrogen gas used for power generation from the fuel cell 40 to the discharge manifold 6. A discharge path 361 for discharging the hydrogen gas from the fuel cell 41 to the discharge manifold 6 is provided. The discharge paths 360 and 361 are provided in the insulating portion ZT so that the lines extending in the discharge directions Xa and Xb do not intersect in the discharge manifold 6.

  According to the above configuration, the insulating property is ensured between the stacked bodies STa and STb of the fuel cells 40 and 41, and the supply manifold 5 and the discharge manifold are shared, thereby reducing the size of the fuel cell 9. It becomes possible.

  Further, since the lines extending in the discharge directions Xa and Xb of the discharge paths 360 and 361 do not intersect in the discharge manifold 6, the generated water flowing from the fuel cell 40 to the discharge manifold 6 and the discharge manifold 6 from the fuel cell 41 are discharged. The generated water that flows into the cross does not intersect within the discharge manifold 6 to form a liquid bridge. For this reason, it is prevented that the laminated bodies STa and STb are electrically connected to lose insulation.

  Therefore, the fuel cell 9 according to the embodiment can prevent a short circuit between the stacked bodies STa and STb and can be downsized.

  The above-described embodiment is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

5, 5a Discharge manifold 9, 9a Fuel cell 40, 41 Fuel cell 360, 361 Discharge path Xa, Xb Discharge direction ZT Insulation part

Claims (1)

A first power generation unit that generates power using an oxidizing gas and a fuel gas and is stacked over a plurality of layers;
A second power generation unit that generates power using an oxidizing gas and a fuel gas and is stacked adjacent to the first power generation unit over a plurality of layers;
An insulating portion that insulates between the first power generation unit and the second power generation unit;
The insulating part is
A manifold penetrating in the stacking direction of the first power generation unit and the second power generation unit;
A first discharge path for discharging one of the oxidizing gas and the fuel gas used for power generation from the first power generation unit to the manifold;
A second discharge path for discharging the one gas from the second power generation unit to the manifold,
The fuel cell according to claim 1, wherein the first discharge path and the second discharge path are provided in the insulating portion so that lines extending in the respective discharge directions do not intersect within the manifold.

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