JP2014127458A - Fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell in which retention of bubbles can be suppressed while minimizing output reduction.SOLUTION: A fuel cell 3 includes a cell stack 10 formed by laminating a plurality of unit cells 45 in the horizontal direction. In the cell stack 10, a fuel supply path 88 for supplying liquid fuel to the plurality of unit cells 45, respectively, and a fuel discharge path 90 for discharging liquid fuel from the plurality of unit cells 45, respectively, are formed. At the upper end of the fuel discharge path 90, an inclined plane 101 is formed so that the downstream of liquid fuel in the discharge direction Y is located on the upper side of upstream of liquid fuel in the discharge direction Y.

Description

  The present invention relates to a fuel cell, and more particularly to a polymer electrolyte fuel cell.

  Conventionally, a fuel cell using a liquid fuel such as methanol, dimethyl ether or hydrazine is known as a polymer electrolyte fuel cell.

  As such a fuel cell, for example, a fuel cell having a stack structure in which a plurality of unit cells are stacked has been proposed (see, for example, Patent Document 1 below). The unit cell has an electrolyte layer made of a solid polymer film, a fuel side electrode and an oxygen side electrode arranged opposite to each other with the electrolyte layer interposed therebetween, a fuel side separator arranged opposite to the fuel side electrode, and an oxygen side electrode And an oxygen side separator to be disposed.

  In such a fuel cell, liquid fuel is supplied to the fuel-side electrode, and oxygen (air) is supplied to the oxygen-side electrode, whereby an electrochemical reaction occurs in each unit cell to generate electric power. .

JP 2005-276564 A

  However, in the fuel cell described in Patent Document 1, when an electrochemical reaction occurs, liquid fuel is decomposed at the fuel side electrode to generate gas, and the generated gas may stay as bubbles in the liquid fuel. In this case, the bubbles stay in the fuel cell, thereby obstructing the contact between the fuel side electrode and the liquid fuel, resulting in a decrease in the output of the fuel cell.

  Accordingly, an object of the present invention is to provide a fuel cell that can suppress the retention of bubbles in the fuel cell and suppress the decrease in output.

  In order to achieve the above-described object, the fuel cell of the present invention includes a stacked structure formed by stacking a plurality of unit cells in the horizontal direction, and the stacked structure includes a stacking direction of the plurality of unit cells. A plurality of unit cells, a fuel supply path for supplying liquid fuel to each of the plurality of unit cells, and a plurality of unit cells that pass through the plurality of unit cells in the stacking direction. And a fuel discharge path for discharging liquid fuel from the upper side of the vertical direction of the fuel discharge path, the downstream side of the discharge direction is higher than the upstream side of the discharge direction of the liquid fuel. It is characterized in that a bubble guide portion formed so as to be located at is provided.

  According to such a configuration, since the stacked structure has the fuel supply path and the fuel discharge path, the liquid fuel is supplied to each unit cell of the stacked structure via the fuel supply path and the fuel discharge path. Supply and discharge can be ensured, and power can be generated in each unit cell.

  However, bubbles (hereinafter simply referred to as bubbles) in the liquid fuel generated by power generation are moved into the fuel discharge path along with the flow of the liquid fuel, and further, fuel is generated in the fuel discharge path by buoyancy. It reaches the upper end in the vertical direction of the discharge path, that is, the bubble guide.

  And since the bubble guide part is formed so that the downstream side is positioned on the upper side in the vertical direction from the upstream side in the discharge direction, the bubbles that have reached the bubble guide part are upstream in the discharge direction by the bubble guide part. From the fuel cell to the downstream side, and further discharged from the fuel cell together with the liquid fuel.

  Therefore, according to the fuel cell of the present invention, bubbles can be prevented from staying in the liquid fuel in the fuel cell, and a decrease in output can be suppressed.

  In the fuel cell of the present invention, it is preferable that the bubble guide portion is formed so as to be inclined upward in the vertical direction toward the downstream side in the discharge direction.

  According to such a configuration, since the bubble guide portion is formed so as to be inclined upward in the vertical direction as it goes downstream in the discharge direction, the bubble that has reached the bubble guide portion is It is moved from the upstream side in the discharge direction toward the downstream side along the inclination of the part. That is, the bubble guide unit can reliably guide the bubbles that have reached the bubble guide unit toward the downstream side in the discharge direction.

  Therefore, it is possible to reliably suppress bubbles from staying in the liquid fuel in the fuel cell, and it is possible to reliably suppress a decrease in the output of the fuel cell.

  Further, in the fuel cell of the present invention, each of the plurality of unit cells includes a membrane electrode assembly and a pair of separators arranged to face each other in the stacking direction so as to sandwich the membrane electrode assembly. The pair of separators are formed with a fuel supply port through which liquid fuel to be supplied to the unit cell passes and a fuel discharge port through which the liquid fuel discharged from the unit cell passes, and the fuel supply path Is formed by laminating the plurality of unit cells, and the plurality of fuel supply ports communicating with each other in the laminating direction, and the fuel discharge path is formed by laminating the plurality of unit cells, The fuel discharge port is formed by communicating with each other in the stacking direction, and the bubble guide portion is formed as a separate member from the separator, and is formed by a first guide member provided in the fuel discharge path. It is preferable that you are.

  According to such a configuration, each unit cell includes a membrane electrode assembly and a pair of separators. Therefore, each unit cell can generate power in each membrane electrode assembly, but each unit is adjacent to each other by each separator. It can suppress reliably that the membrane electrode assembly of a cell will mutually short-circuit. Therefore, the power generation efficiency of the fuel cell can be improved.

  In the above configuration, the fuel supply ports formed in each separator communicate with each other in the stacking direction, thereby forming a fuel supply path, and the fuel discharge ports formed in each separator communicate with each other in the stacking direction. Thus, a fuel discharge path is formed.

  However, when the fuel discharge path is formed from the fuel discharge ports of a plurality of separators, there is a limit in smoothly forming the vertical upper end portion of the fuel discharge path due to the dimensional tolerance of each separator and the fuel discharge port. For this reason, an undesired step may be formed at the upper end portion in the vertical direction of the fuel discharge path due to the upper end edges of the fuel discharge ports adjacent to each other. As a result, bubbles may accumulate at the step formed in the fuel discharge path, and the discharge of bubbles from within the fuel cell may be suppressed.

  On the other hand, according to the above configuration, the bubble guide portion provided at the upper end in the vertical direction of the fuel discharge path is formed by the first guide member configured as a separate member from the separator. Compared with the case where the guide portion is formed by the upper end edges of the plurality of fuel discharge ports being continuous, the bubble guide portion can be formed smoothly.

  Therefore, the power generation efficiency of the fuel cell can be improved while the structure is simple, and the discharge of bubbles from the fuel cell can be facilitated.

  However, in recent years, from the viewpoint of improving output power, an increase in the number of unit cells to be stacked (the number of unit cells stacked) has been studied. However, when the number of unit cells is increased, the stacked structure may be deformed so as to be bent downward in the vertical direction due to its own weight. In this case, each of the fuel supply path and the fuel discharge path is deformed so as to curve downward as the stacked structure is deformed.

  As a result, bubbles may stay in a portion located relatively above the fuel discharge path, and the discharge of bubbles from within the fuel cell may be suppressed.

  Also, during maintenance of the fuel cell, etc., the liquid fuel in the fuel cell is discharged out of the fuel cell from the viewpoint of electric shock prevention.If the fuel supply path and the fuel discharge path are deformed as described above, In some cases, the liquid fuel remains in a relatively lower portion of each of the fuel supply path and the fuel discharge path.

  On the other hand, according to said structure, since the 1st guide member is provided in the fuel discharge path, even if it increases the number of lamination | stacking of a unit cell, it can suppress that a laminated structure deform | transforms.

  Therefore, the retention of bubbles in the fuel discharge path can be reliably suppressed, and liquid fuel can be prevented from remaining in each of the fuel supply path and the fuel discharge path during maintenance of the fuel cell. Improvements can be made.

  That is, it is possible to improve the maintainability of the fuel cell while improving the output power.

  In the fuel cell of the present invention, the fuel supply passage is formed at the lower end portion in the vertical direction so that the downstream side in the supply direction is located above the upstream side in the supply direction of the liquid fuel. It is preferable that a first drainage guide portion is provided.

  According to such a configuration, the first drainage guide portion formed so that the downstream side is located on the upper side in the vertical direction from the upstream side in the supply direction is provided at the lower end portion in the vertical direction of the fuel supply path. Therefore, during the maintenance of the fuel cell, the liquid fuel is guided toward the upstream side in the supply direction by the first drain guide part. Therefore, the liquid fuel in the fuel cell can be reliably discharged from the fuel cell to the outside of the fuel cell. As a result, it is possible to further improve the maintainability of the fuel cell.

  In the fuel cell of the present invention, the stacked structure passes through the plurality of unit cells in the stacking direction of the plurality of unit cells, and supplies oxygen to each of the plurality of unit cells. And an exhaust passage for passing through the plurality of unit cells in the stacking direction and exhausting from each of the plurality of unit cells, and at a lower end portion in the vertical direction of the exhaust passage, It is preferable that a second drainage guide portion is provided so that the downstream side in the discharge direction is positioned below the vertical direction rather than the upstream side.

  According to such a configuration, since the laminated structure has the oxygen supply path and the exhaust path, oxygen can be reliably supplied to and discharged from each unit cell. Therefore, since liquid fuel and oxygen can be reliably supplied to and discharged from each unit cell, the power generation efficiency of each unit cell can be improved, and consequently the power generation efficiency of the fuel cell can be improved.

  However, in a fuel cell using liquid fuel, a crossover may occur in which the liquid fuel passes through the membrane electrode assembly. And since the liquid fuel which crossed over inhibits supply of oxygen with respect to the oxygen side electrode of a membrane electrode assembly, the electromotive force of a fuel cell falls.

  On the other hand, according to the above configuration, the crossover liquid fuel is moved into the exhaust passage along with the flow of oxygen, and by its own weight, the lower end in the vertical direction of the exhaust passage, that is, the second drainage guide portion. To reach.

  And since the 2nd drainage guide part is formed so that the downstream side may be located in the lower side of the perpendicular direction rather than the upstream side of the discharge direction, the liquid fuel that has reached the second drainage guide part is the second It is guided by the drain guide part toward the downstream side in the discharge direction and discharged from the fuel cell.

  Therefore, the crossover liquid fuel can be smoothly discharged from the fuel cell, and it is possible to suppress the crossover liquid fuel from inhibiting the supply of oxygen to the oxygen side electrode. As a result, a decrease in the electromotive force of the fuel cell can be suppressed.

  According to the fuel cell of the present invention, retention of bubbles in the fuel cell can be suppressed, and a decrease in output can be suppressed.

FIG. 1 shows a schematic configuration diagram of an electric vehicle equipped with a first embodiment of a fuel cell of the present invention. FIG. 2 is an exploded perspective view of the fuel cell shown in FIG. 1 as viewed from the front right side. 3 (a) is a front view of the fuel cell shown in FIG. 2, and FIG. 3 (b) is a cross-sectional view taken along line AA of the fuel cell shown in FIG. 3 (a). 4A is a front view of the fuel cell shown in FIG. 2, and FIG. 4B is a cross-sectional view taken along line BB of the fuel cell shown in FIG. 4A. FIG. 5 shows a perspective view of the insert member shown in FIG. 6A and 6B are explanatory diagrams for explaining the power generation operation of the fuel cell, in which FIG. 6A is a cross-sectional view taken along line AA of FIG. 3A during the power generation operation, and FIG. The BB sectional view of the fuel cell shown in Drawing 4 (a) at the time of power generation operation is shown. FIG. 7A is a front view of a fuel cell as a second embodiment of the present invention, and FIG. 7B is a cross-sectional view of the fuel cell shown in FIG.

1. 1 is a schematic configuration diagram of an electric vehicle on which the first embodiment of the fuel cell of the present invention is mounted. In FIG. 1, an electric vehicle 1 is a hybrid vehicle that selectively uses a fuel cell 3 and a battery 37 as a power source, and is equipped with a fuel cell system 2 as a vehicle fuel cell system.

  The fuel cell system 2 includes a fuel cell 3, a fuel supply / exhaust unit 4, an air supply / exhaust unit 5, a control unit 6, and a power unit 7.

In the following description, regarding the electric vehicle 1 and the fuel cell 3, when referring to the direction, the direction when the electric vehicle 1 is arranged on a horizontal plane is used as a reference, and specifically, shown in each drawing. Based on the arrow direction. That is, the front-rear direction and the left-right direction are horizontal directions, and the up-down direction is a vertical direction. The front-rear direction is an example of the stacking direction.
(1) Fuel Cell Although the fuel cell 3 will be described in detail later, it is a direct liquid fuel type fuel cell to which liquid fuel is directly supplied, and is configured as an anion exchange type fuel cell. The fuel cell 3 is disposed on the lower center side of the electric vehicle 1.

The output voltage of the fuel cell 3 is, for example, 0.2 to 1.5 V, and the output current is, for example, 10 to 400A. These outputs are outputs per unit cell 45 (described later).
(2) Fuel Supply / Discharge Unit The fuel supply / discharge unit 4 is configured to supply liquid fuel to the fuel cell 3, and is disposed on the rear side of the fuel cell 3 in the electric vehicle 1.

  The fuel supply / discharge unit 4 is discharged from the fuel cell 15, a fuel tank 15 for storing liquid fuel, a fuel supply pipe 17 for supplying liquid fuel supplied from the fuel tank 15 to the fuel cell 3, and the fuel cell 3. And a reflux pipe 16 for returning the liquid fuel to the fuel supply pipe 17.

  The fuel tank 15 is disposed at the rear end portion of the electric vehicle 1 and has a substantially box shape.

  Examples of the liquid fuel stored in the fuel tank 15 include a hydrogen-containing liquid fuel. The hydrogen-containing liquid fuel is a liquid fuel containing hydrogen atoms in the molecule, and examples thereof include alcohols such as methanol, ethers having an alkyl group such as dimethyl ether, and hydrazines, preferably alcohols. And hydrazines, more preferably hydrazines.

Specific examples of hydrazines include hydrazine (NH ₂ NH ₂ ), hydrated hydrazine (NH ₂ NH ₂ .H ₂ O), hydrazine carbonate ((NH ₂ NH ₂ ) ₂ CO ₂ ), hydrazine hydrochloride ( NH ₂ NH ₂ · HCl), hydrazine sulfate _{(NH 2 NH 2 · H 2} SO 4), monomethyl hydrazine _(CH 3 NHNH _2), dimethylhydrazine _{((CH 3) 2 NNH 2} , CH 3 NHNHCH 3), a carboxylic hydrazide ((NHNH ₂ ) ₂ CO) and the like. The liquid fuels exemplified above can be used alone or in combination of two or more.

Among the above fuel compounds, compounds that do not contain carbon, that is, hydrazine, hydrated hydrazine, hydrazine sulfate, etc., do not generate CO and CO ₂ , and do not cause catalyst poisoning. Can be achieved, and substantially zero emission can be realized.

  Further, as the above exemplified liquid fuel, the above fuel compound may be used as it is. However, the above exemplified fuel compound may be water and / or alcohol (for example, lower alcohol such as methanol, ethanol, propanol, isopropanol). Etc.). In this case, the concentration of the fuel compound in the solution varies depending on the type of the fuel compound, but is, for example, 1 to 90% by mass, preferably 1 to 30% by mass.

  The fuel supply pipe 17 is provided so as to connect the fuel tank 15 and the fuel cell 3. Specifically, one end (rear end) of the fuel supply pipe 17 is connected to the bottom wall of the fuel tank 15, and the other end (front end). ) Is connected to a fuel supply unit 92 described later.

  The reflux pipe 16 is provided so as to connect the fuel cell 3 and the fuel supply pipe 17. Specifically, one end portion (front end portion) thereof is connected to a fuel discharge portion 97 described later, and the other end portion (lower end portion). Is connected in the middle of the fuel supply pipe 17, that is, in a substantially central portion in the front-rear direction.

  Therefore, the fuel cell 3, the reflux pipe 16, and the front part of the fuel supply pipe 17 are configured so that the liquid fuel discharged from the fuel discharge portion 97 described later again passes through the reflux pipe 16 and the fuel supply pipe 17 to the fuel described later. A closed line (closed flow path) formed to flow to the supply unit 92 is configured. Thereby, the liquid fuel is circulated in the fuel cell 3.

  The fuel supply / discharge unit 4 includes a gas-liquid separator 18 for separating liquid fuel and gas (gas), and a gas discharge pipe 22 for discharging the gas separated by the gas-liquid separator 18. A first fuel transport pump 19 and a second fuel transport pump 20 for transporting liquid fuel to the fuel cell 3 are provided.

  The gas-liquid separator 18 is interposed in the middle of the reflux pipe 16 on the rear upper side of the fuel cell 3. The gas-liquid separator 18 is formed in a substantially box shape, and two bottom flow ports 24 are formed on the bottom wall, and one upper flow port 25 is formed on the upper end of the rear wall.

  The gas-liquid separator 18 is interposed in the reflux pipe 16 by connecting the two bottom flow ports 24 to the reflux pipe 16. Thereby, as for the gas-liquid separator 18, the internal space forms a part of closed line.

  The gas discharge pipe 22 is provided so as to communicate the upper flow port 25 and the external space of the electric vehicle 1. Specifically, one end (front end) of the gas discharge pipe 22 is connected to the upper flow port 25 and the other end (rear) Edge) is open to the atmosphere.

  The first fuel transport pump 19 is interposed in the rear portion of the fuel supply pipe 17, and is disposed between the connection portion of the reflux pipe 16 and the fuel supply pipe 17 and the fuel tank 15.

  Examples of the first fuel transport pump 19 include known liquid feed pumps such as rotary pumps such as rotary pumps and gear pumps, and reciprocating pumps such as piston pumps and diaphragm pumps.

  The second fuel transport pump 20 is interposed in the front portion of the fuel supply pipe 17 and is disposed between the connection portion of the reflux pipe 16 and the fuel supply pipe 17 and the fuel cell 3.

  Examples of the second fuel transport pump 20 include a known liquid feed pump similar to the first fuel transport pump 19.

  Each of the first fuel transport pump 19 and the second fuel transport pump 20 is electrically connected to a control unit 34 (described later) (see the broken line in FIG. 1). Thereby, a control signal from the control unit 34 (described later) is input to each of the first fuel transport pump 19 and the second fuel transport pump 20, and the control unit 34 (described later) transmits the first fuel transport pump 19 and the second fuel transport pump 19. 2 Controls the driving and stopping of each fuel transport pump 20.

  Further, the fuel supply / discharge section 4 is provided with a fuel supply valve 21 for opening and closing the fuel supply pipe 17 and a gas discharge valve 23 for opening the gas discharge pipe 22.

  The fuel supply valve 21 is interposed in the front portion of the fuel supply pipe 17 and is disposed between the connection portion of the reflux pipe 16 and the fuel supply pipe 17 and the first fuel transport pump 19. Examples of the fuel supply valve 21 include known on-off valves such as electromagnetic valves.

  When the fuel supply valve 21 is opened, liquid fuel can be supplied from the fuel tank 15 to the fuel cell 3, and when the fuel supply valve 21 is closed, the fuel tank 15 is connected to the fuel cell 3. Liquid fuel supply is regulated.

  Moreover, the gas discharge valve 23 is interposed in the middle of the gas discharge pipe 22, and as the gas discharge valve 23, for example, a known on-off valve such as an electromagnetic valve can be cited.

  Then, by opening the gas discharge valve 23, the gas can be discharged from the gas-liquid separator 18, the pressure in the gas-liquid separator 18 is released, and the gas discharge valve 23 is closed, The gas discharge from the gas-liquid separator 18 is restricted.

Each of the fuel supply valve 21 and the gas discharge valve 23 is electrically connected to a control unit 34 (described later) (see the broken line in FIG. 1). Thereby, a control signal from the control unit 34 (described later) is input to each of the fuel supply valve 21 and the gas discharge valve 23, and the control unit 34 (described later) controls each of the fuel supply valve 21 and the gas discharge valve 23. Controls opening and closing.
(3) Air Supply / Exhaust Unit The air supply / exhaust unit 5 includes an air supply pipe 26 for supplying air to the fuel cell 3, and an air discharge pipe 27 for discharging the air discharged from the fuel cell 3 to the outside. It has.

  The air supply pipe 26 is provided so as to communicate the external space of the electric vehicle 1 and the fuel cell 3. Specifically, one end (front end) of the air supply pipe 26 is opened to the atmosphere, and the other end (rear end) is provided. It is connected to an oxygen supply unit 95 (described later).

  The air discharge pipe 27 is provided so as to communicate the external space of the electric vehicle 1 and the fuel cell 3. Specifically, one end (front end) of the air discharge pipe 27 is opened to the atmosphere (drain), and the other end ( The rear end portion is connected to an exhaust portion 94 (described later).

  The air supply / discharge unit 5 is provided with an air supply pump 28 for sending air to the fuel cell 3 and a fuel recovery unit 31 for recovering liquid fuel that has been crossed over (described later).

  The air supply pump 28 is interposed in the front portion of the air supply pipe 26. Examples of the air supply pump 28 include known air supply pumps such as an air compressor. The air supply pump 28 is electrically connected to a control unit 34 (described later) (see the broken line in FIG. 1). Thereby, a control signal from the control unit 34 (described later) is input to the air supply pump 28, and the control unit 34 (described later) controls driving and stopping of the air supply pump 28.

  The fuel recovery unit 31 is interposed in the rear portion of the air discharge pipe 27 and is disposed downstream of the fuel cell 3 in the air flow direction in the air discharge pipe 27. The fuel recovery part 31 is formed in a substantially box shape, an inflow port 32 is formed at the upper end of the rear wall, and an exhaust port 33 is formed at the upper end of the front wall.

  The fuel recovery unit 31 is interposed in the air discharge pipe 27 by connecting each of the inflow port 32 and the exhaust port 33 to the air discharge pipe 27.

  Further, the air supply / discharge section 5 is provided with an air supply valve 29 for opening and closing the air supply pipe 26 and an air discharge valve 30 for opening and closing the air discharge pipe 27.

  The air supply valve 29 is interposed in the rear portion of the air supply pipe 26 and is disposed between the air supply pump 28 and the fuel cell 3. Examples of the air supply valve 29 include a known on-off valve such as an electromagnetic valve.

  When the air supply valve 29 is opened, air can be supplied to the fuel cell 3, and when the air supply valve 29 is closed, the supply of air to the fuel cell 3 is restricted.

  The air discharge valve 30 is interposed in the rear portion of the air discharge pipe 27 and is disposed downstream of the fuel recovery unit 31 in the air flow direction. Examples of the air discharge valve 30 include a known on-off valve such as an electromagnetic valve.

  When the air discharge valve 30 is opened, air can be discharged from the fuel cell 3, and when the air discharge valve 30 is closed, the discharge of air from the fuel cell 3 is regulated.

Each of the air supply valve 29 and the air discharge valve 30 is electrically connected to a control unit 34 (described later) (see the broken line in FIG. 1). Thereby, a control signal from the control unit 34 (described later) is input to each of the air supply valve 29 and the air discharge valve 30, and the control unit 34 (described later) receives each of the air supply valve 29 and the air discharge valve 30. Controls opening and closing.
(4) Control Unit The control unit 6 includes a control unit 34 for controlling the fuel cell system 2.

The control unit 34 is a unit (for example, ECU: Electronic Control Unit) that executes electrical control in the electric vehicle 1 and is configured by a microcomputer including a CPU, a ROM, a RAM, and the like.
(5) Power unit The power unit 7 includes a motor 35 for converting electrical energy output from the fuel cell 3 into mechanical energy as a driving force of the electric vehicle 1, and an inverter 36 electrically connected to the motor 35. A power battery 37 for storing regenerative energy by the motor 35 and a DC / DC converter 38 are provided.

  The motor 35 is disposed at the front end of the electric vehicle 1 and is disposed in front of the fuel cell 3. Examples of the motor 35 include known three-phase motors such as a three-phase induction motor and a three-phase synchronous motor.

  The inverter 36 is disposed between the motor 35 and the fuel cell 3. The inverter 36 is a device that converts DC power generated by the fuel cell 3 into AC power. Examples of the inverter 36 include a power conversion device in which a known inverter circuit is incorporated. The inverter 36 is electrically connected to the fuel cell 3 and the motor 35 by wiring, and is electrically connected to the control unit 34 (not shown), thereby generating power from the fuel cell 3. I have control.

  As the power battery 37, for example, a nickel hydride battery having a rated voltage of about 100V, a known secondary battery such as a lithium ion battery, and the like can be cited. The power battery 37 is connected to the wiring between the inverter 36 and the fuel cell 3. Thus, the power battery 37 is configured to be able to store the power from the fuel cell 3 and to supply power to the motor 35.

  The DC / DC converter 38 is disposed between the power battery 37 and the fuel cell 3. The DC / DC converter 38 has a function of increasing / decreasing the output voltage of the fuel cell 3, and a function of adjusting the power of the fuel cell 3 and the input / output power of the power battery 37.

  The DC / DC converter 38 is electrically connected to the control unit 34 (see the broken line in FIG. 1), and accordingly, the fuel cell 3 according to the input of the output control signal output from the control unit 34. Controls the output (output voltage).

  Further, the DC / DC converter 38 is electrically connected to the fuel cell 3 and the power battery 37 by wiring, and is also electrically connected to the inverter 36 by branching of the wiring.

As a result, power from the DC / DC converter 38 to the motor 35 is converted from DC power to three-phase AC power in the inverter 36 and supplied to the motor 35 as three-phase AC power.
2. 2. Details of Fuel Cell As shown in FIG. 2, the fuel cell 3 includes a cell stack 10 as an example of a laminated structure and a pair of covers 11 provided so as to sandwich the cell stack 10.

  The cell stack 10 is formed by stacking a plurality of unit cells 45 in the front-rear direction.

  Each unit cell 45 includes a membrane electrode assembly 46 and an anode side separator 47 and a cathode side separator 48 as an example of a pair of separators.

  The membrane electrode assembly 46 is formed in a substantially flat plate shape that is substantially rectangular in a front view extending in the left-right direction, and an electrolyte layer 50 and an anode as a fuel-side electrode that are disposed opposite to each other across the electrolyte layer 50 in the front-rear direction. An electrode 51 and a cathode electrode 52 as an oxygen side electrode are provided.

  The electrolyte layer 50 is formed of an anion exchange type polymer electrolyte membrane. The film thickness of the electrolyte layer 50 is, for example, 10 to 100 μm.

  The anode 51 is formed on the entire rear surface of the electrolyte layer 50 by, for example, a catalyst carrier that supports a catalyst. Note that the catalyst can be directly formed as the anode electrode 51 without using the catalyst carrier. The anode electrode 51 is formed with a thickness of 10 to 200 μm, preferably 20 to 100 μm, for example.

  The cathode electrode 52 is formed on the entire front surface of the electrolyte layer 50 by a catalyst carrier that supports a catalyst, for example, in the same manner as the anode electrode 51. The cathode electrode 52 is formed with a thickness of, for example, 10 to 300 μm, preferably 20 to 150 μm.

  The anode-side separator 47 is disposed adjacent to the rear side of the membrane electrode assembly 46 and includes an anode-side separator body 53 and an anode-side seal 54.

  The anode-side separator body 53 is formed in a substantially flat plate shape that is larger than the membrane electrode assembly 46 and has a substantially rectangular shape in front view.

  As shown in FIGS. 2 to 4, an anode side fuel supply port 55 as an example of a fuel supply port, an anode side cooling medium supply port 56, and an anode side exhaust port 57 are provided at the lower end of the anode side separator body 53. Are arranged in the left-right direction.

  As shown in FIG. 2, the anode side fuel supply port 55 is an opening for supplying liquid fuel to a fuel flow path 62 to be described later, and is disposed at the lower right end of the anode side separator body 53. Yes. The anode side fuel supply port 55 is formed to penetrate in a substantially rectangular shape when viewed from the front.

The anode side cooling medium supply port 56 is an opening for supplying a cooling medium to a first cooling medium flow path 63 to be described later, and is arranged at the center in the left-right direction at the lower end of the anode side separator body 53. The anode side cooling medium supply port 56 is formed to penetrate in a substantially rectangular shape when viewed from the front.
As shown in FIGS. 4A and 4B, the anode side exhaust port 57 is an opening for exhausting from an oxygen flow path 79 to be described later, and is the lower left end of the anode side separator body 53. Is arranged. The anode side exhaust port 57 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  Further, as shown in FIG. 2, an anode side fuel discharge port 58, an anode side cooling medium discharge port 59, and an anode side oxygen supply port 60 as an example of a fuel discharge port are provided at the upper end of the anode side separator body 53. Are arranged in the left-right direction.

  The anode-side fuel discharge port 58 is an opening for discharging liquid fuel from a fuel flow path 62 described later, and is disposed at the upper left end of the anode-side separator body 53. The anode side fuel discharge port 58 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  The anode-side cooling medium discharge port 59 is an opening for discharging the cooling medium from a first cooling medium flow path 63 described later, and is arranged at the center in the left-right direction of the upper end portion of the anode-side separator body 53. The anode side cooling medium discharge port 59 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  The anode-side oxygen supply port 60 is an opening for supplying oxygen to an oxygen channel 79 described later, and is disposed at the upper right end of the anode-side separator body 53. The anode side oxygen supply port 60 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  Further, the anode separator body 53 has a fuel flow path forming region A1 defined on the front surface thereof and a first cooling medium flow path forming region (not shown) defined on the rear surface thereof.

  The fuel flow path forming region A <b> 1 is disposed at the central portion on the front surface of the anode separator main body 53. The fuel flow path forming region A1 is formed in substantially the same shape and size as the membrane electrode assembly 46, and specifically, is formed in a substantially rectangular shape in front view extending in the left-right direction.

  A plurality of fuel flow paths 62 are formed in the fuel flow path forming region A1. Each of the plurality of fuel flow paths 62 is formed as a groove that is recessed rearward from the front surface of the fuel flow path forming region A1 and extends vertically, and is arranged in parallel in the left-right direction at intervals.

  The first cooling medium flow path forming region (not shown) is disposed at the central portion on the rear surface of the anode-side separator body 53. Although not shown, the first cooling medium flow path formation region (not shown) has a lower end communicating with the anode side cooling medium supply port 56 and an upper end connected with the anode side cooling medium discharge port 59. Communicate.

  Further, as shown in FIG. 3B, a plurality of first cooling medium flow paths 63 are formed in the first cooling medium flow path forming region (not shown). The first cooling medium flow path 63 is formed as a groove portion that is recessed forward from the rear surface of a first cooling medium flow path forming region (not shown) and extends vertically, and is parallel to each other with a space in the left-right direction. Has been placed.

  A thin portion 64 is formed on the rear surface of the anode separator main body 53.

  When the thin portion 64 is projected in the front-rear direction (thickness direction of the anode separator 47), the edge of the projection surface of the fuel flow path formation region A1, the anode fuel supply port 55, and the anode fuel discharge port 58 It is formed in two places in the area between the edge of each projection plane. In addition, in FIG. 2, the thin part 64 is abbreviate | omitted for convenience.

  The thin portion 64 is formed so as to be recessed forward from the rear surface of the anode-side separator body 53, and the thickness of the anode-side separator body 53 is reduced. The thin portion 64 is formed to face each of the anode side fuel supply port 55 and the anode side fuel discharge port 58.

  The thin portion 64 is formed with a fuel through hole 65 for allowing liquid fuel supplied and discharged through the anode side fuel supply port 55 and the anode side fuel discharge port 58 to pass therethrough.

  More specifically, the fuel through hole 65 formed in the thin portion 64 facing the anode side fuel supply port 55 is connected to the anode side fuel supply port 55 and the lower end portion of the fuel flow path 62 so as to communicate with each other. It is formed through the side separator body 53. The fuel through-hole 65 formed in the thin portion 64 facing the anode-side fuel discharge port 58 communicates the anode-side fuel discharge port 58 and the upper end of the fuel flow path 62 with the anode-side separator body 53. Is formed.

  As shown in FIGS. 2 and 3, the anode-side seal 54 is tightly fixed to the front surface of the anode-side separator body 53, and integrally includes an anode-side diffusion layer 66 and an anode-side seal portion 67. .

  The anode-side diffusion layer 66 is formed of a hard gas-permeable material, such as carbon paper or carbon cloth, which is fluorine-treated if necessary, and is formed in a substantially rectangular flat plate shape having a substantially rectangular shape when viewed from the front. The anode-side diffusion layer 66 is formed in substantially the same shape and size as the membrane electrode assembly 46, and specifically, is formed in a substantially rectangular shape in front view extending in the left-right direction. The anode-side diffusion layer 66 is disposed so as to face the fuel flow path formation region A1 in the front-rear direction.

  The anode side seal portion 67 is made of an elastic material such as rubber, for example, is provided so as to surround the anode side diffusion layer 66, and is joined to the peripheral end portion of the anode side diffusion layer 66. . Further, the anode-side seal portion 67 is formed such that the length (thickness) in the front-rear direction is longer than the length (thickness) in the front-rear direction of the anode-side diffusion layer 66. It bulges to the front side.

  In the anode-side seal portion 67, three first openings 68 are formed in the left-right direction below the anode-side diffusion layer 66. The first opening 68 is disposed corresponding to each of the anode side fuel supply port 55, the anode side cooling medium supply port 56, and the anode side exhaust port 57, and is formed through the anode side seal portion 67 in the front-rear direction. ing. Each of the three first openings 68 has a shape and size corresponding to each of the corresponding anode-side fuel supply port 55, anode-side cooling medium supply port 56, and anode-side exhaust port 57 when projected in the front-rear direction. Is formed. The first opening 68 corresponding to the anode fuel supply port 55 corresponds as an example of a fuel supply port, and the first opening 68 corresponding to the anode side exhaust port 57 corresponds as an example of an oxygen discharge port. .

  As shown in FIGS. 3 and 4, each of the three first openings 68 includes a corresponding anode-side fuel supply port 55, anode-side cooling medium supply port 56, and anode-side exhaust port 57. Adjacent to each other so as to communicate with each other in the direction.

  Further, as shown in FIG. 2, three second openings 69 are formed in the anode-side seal portion 67 so as to be aligned in the left-right direction above the anode-side diffusion layer 66. The second opening 69 is disposed corresponding to each of the anode-side fuel discharge port 58, the anode-side cooling medium discharge port 59, and the anode-side oxygen supply port 60, and is formed through the anode-side seal portion 67 in the front-rear direction. Has been. Each of the three second openings 69 has a shape and a size that match the corresponding anode-side fuel discharge port 58, anode-side cooling medium discharge port 59, and anode-side oxygen supply port 60 when projected in the front-rear direction. Is formed. The second opening 69 corresponding to the anode side fuel discharge port 58 corresponds as an example of the fuel discharge port, and the second opening 69 corresponding to the anode side oxygen supply port 60 corresponds as an example of the oxygen supply port. To do.

  Each of the three second openings 69 has a corresponding anode-side fuel discharge port 58, anode-side coolant discharge port 59, and anode-side oxygen supply port 60, as shown in FIGS. Adjacently arranged so as to communicate with each other in the front-rear direction.

  As shown in FIG. 2, the cathode side separator 48 is disposed adjacent to the front side of the membrane electrode assembly 46. That is, the anode-side separator 47 and the cathode-side separator 48 are opposed to each other in the front-rear direction so as to sandwich the membrane electrode assembly 46.

  The cathode side separator 48 includes a cathode side separator body 70 and a cathode side seal 71.

  Similarly to the anode-side separator 47, the cathode-side separator body 70 is formed in a substantially flat plate shape that is larger than the membrane electrode assembly 46 and has a substantially rectangular shape in front view.

  Further, a cathode side fuel supply port 72, a cathode side cooling medium supply port 73, and a cathode side exhaust port 74 as an example of a fuel supply port are arranged at the lower end portion of the cathode side separator body 70 in the left-right direction. Is formed.

  The cathode side fuel supply port 72 is an opening for supplying fuel to the fuel flow path 62, and is disposed at the lower right end of the cathode side separator body 70. The cathode side fuel supply port 72 is formed in a substantially rectangular shape when viewed from the front.

  The cathode side cooling medium supply port 73 is an opening for supplying a cooling medium to a second cooling medium flow path 78 described later, and is arranged at the center in the left-right direction of the lower end portion of the cathode side separator body 70. The cathode side cooling medium supply port 73 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  The cathode side exhaust port 74 is an opening for exhausting from an oxygen flow path 79 described later, and is disposed at the lower left end of the cathode side separator body 70. The cathode side exhaust port 74 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  Similarly to the anode separator 47, a cathode side fuel discharge port 75 as an example of a fuel discharge port, a cathode side cooling medium discharge port 76, and a cathode side oxygen supply port are provided at the upper end of the cathode side separator body 70. 77 are arranged in the left-right direction.

  The cathode side fuel discharge port 75 is an opening for discharging the liquid fuel from the fuel flow path 62, and is disposed at the upper left end of the cathode side separator body 70. The cathode side fuel discharge port 75 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  The cathode side cooling medium discharge port 76 is an opening for discharging the cooling medium from a second cooling medium flow path 78 described later, and is arranged at the center in the left-right direction of the upper end portion of the cathode side separator body 70. The cathode side cooling medium discharge port 76 is formed to penetrate in a substantially rectangular shape when viewed from the front.

  The cathode side oxygen supply port 77 is an opening for supplying oxygen to an oxygen flow path 79 described later, and is disposed at the upper right end of the cathode side separator body 70. The cathode side oxygen supply port 77 is formed in a substantially rectangular shape when viewed from the front.

  Further, the cathode side separator body 70 has a second cooling medium forming region A2 defined on the front surface thereof and an oxygen flow path forming region (not shown) defined on the rear surface thereof.

  The second cooling medium formation region A2 is disposed at the central portion of the front surface of the cathode separator body 70. Although not shown, the second cooling medium forming region A2 has a lower end portion communicating with the cathode side cooling medium supply port 73 and an upper end portion communicating with the cathode side cooling medium discharge port 76.

  In addition, a plurality of second cooling medium flow paths 78 are formed in the second cooling medium forming region A2. Each of the plurality of second cooling medium flow paths 78 is formed as a groove that is recessed backward from the front surface of the second cooling medium forming region A2 and extends vertically, and is arranged in parallel at intervals in the left-right direction. ing.

  Further, the oxygen flow path forming region (not shown) is disposed in the central portion on the rear surface of the cathode separator body 70. Although not shown, the oxygen flow path forming region (not shown) is formed in substantially the same shape and size as the membrane electrode assembly 46, and specifically, is formed in a substantially rectangular shape in front view extending in the left-right direction. Has been.

  In addition, a plurality of oxygen channels 79 are formed in the oxygen channel forming region (not shown). Each of the plurality of oxygen channels 79 is formed as a groove that is recessed forward from the rear surface of an oxygen channel forming region (not shown) and extends vertically, and is arranged in parallel in the left-right direction at intervals. ing.

  Further, as shown in FIG. 4B, a thin portion 80 is formed on the front surface of the cathode-side separator body 70 as in the case of the rear surface of the anode-side separator 47.

  When the thin portion 80 is projected in the front-rear direction (thickness direction of the cathode separator 48), the edge of the projection surface of the second cooling medium formation region A2, the cathode side oxygen supply port 77, and the cathode side exhaust port 74 It is formed in two places in the area between the edge of each projection plane. In FIG. 2, the thin portion 80 is omitted for convenience.

  As shown in FIG. 4B, the thin portion 80 is formed so as to be recessed backward from the front surface of the cathode side separator body 70, and the thickness of the cathode side separator body 70 is reduced. The thin portion 80 is formed so as to face each of the cathode side oxygen supply port 77 and the cathode side exhaust port 74.

  In addition, the thin portion 80 is formed with an oxygen through hole 81 through which liquid fuel supplied and discharged by the cathode side oxygen supply port 77 and the cathode side exhaust port 74 passes.

  More specifically, the oxygen through-hole 81 formed in the thin portion 80 facing the cathode-side oxygen supply port 77 is connected to the cathode-side oxygen supply port 77 and the upper end portion of the oxygen channel 79 so as to communicate with each other. It is formed through the side separator body 70. The oxygen through hole 81 formed in the thin portion 80 facing the cathode side exhaust port 74 penetrates the cathode side separator body 70 so that the cathode side exhaust port 74 and the lower end portion of the oxygen flow path 79 communicate with each other. Is formed.

  As shown in FIGS. 2 and 4, the cathode side seal 71 is tightly fixed to the rear surface of the cathode side separator body 70 and integrally includes a cathode side diffusion layer 82 and a cathode side seal portion 83. .

  As shown in FIG. 2, the cathode side diffusion layer 82 is made of, for example, a hard gas permeable material similar to the anode side diffusion layer 66, and is formed in a substantially rectangular flat plate shape having a substantially rectangular shape when viewed from the front. Further, the cathode side diffusion layer 82 is formed in substantially the same shape and size as the membrane electrode assembly 46, and specifically, is formed in a substantially rectangular shape in front view extending in the left-right direction. Further, the cathode side diffusion layer 82 is disposed opposite to an oxygen flow path forming region (not shown) in the front-rear direction.

  The cathode-side seal portion 83 is made of an elastic material such as rubber, for example, is provided so as to surround the cathode-side diffusion layer 82, and is joined to the peripheral end portion of the cathode-side diffusion layer 82. . The cathode-side seal portion 83 is formed such that the length in the front-rear direction (thickness direction) is longer than the length in the front-rear direction of the cathode-side diffusion layer 82, and on the rear side of the cathode-side diffusion layer 82. Bulges.

  Further, in the cathode-side seal portion 83, three third openings 84 are formed so as to be aligned in the left-right direction below the cathode-side diffusion layer 82. The third opening 84 is disposed corresponding to each of the cathode side fuel supply port 72, the cathode side cooling medium supply port 73, and the cathode side exhaust port 74, and is formed through the cathode side seal portion 83 in the front-rear direction. ing. Each of the three third openings 84 has a shape and size that match the corresponding cathode side fuel supply port 72, cathode side cooling medium supply port 73, and cathode side exhaust port 74 when projected in the front-rear direction. Is formed. The third opening 84 corresponding to the cathode side fuel supply port 72 corresponds as an example of the fuel supply port, and the third opening 84 corresponding to the cathode side exhaust port 74 corresponds as an example of the oxygen discharge port. .

  As shown in FIGS. 3 and 4, each of the three third openings 84 corresponds to the corresponding cathode side fuel supply port 72, cathode side cooling medium supply port 73, and cathode side exhaust port 74 in the front-rear direction. Are disposed adjacent to the rear side of the corresponding cathode side fuel supply port 72, cathode side cooling medium supply port 73 and cathode side exhaust port 74 so as to communicate with each other, and each of the three first openings 68. The three first openings 68 are adjacent to each other so as to communicate with each other in the front-rear direction.

  Further, as shown in FIG. 2, the cathode side seal portion 83 is formed with three fourth openings 85 arranged in the left-right direction above the cathode side diffusion layer 82. The fourth opening 85 is arranged corresponding to each of the cathode side fuel discharge port 75, the cathode side cooling medium discharge port 76, and the cathode side oxygen supply port 77, and is formed through the cathode side seal portion 83 in the front-rear direction. Has been. Each of the three fourth openings 85 has a shape and a size that match the corresponding cathode-side fuel discharge port 75, cathode-side coolant discharge port 76, and cathode-side oxygen supply port 77 when projected in the front-rear direction. Is formed. The fourth opening 85 corresponding to the cathode-side fuel discharge port 75 corresponds as an example of the fuel discharge port, and the fourth opening 85 corresponding to the cathode-side oxygen supply port 77 corresponds as an example of the oxygen supply port. To do.

  As shown in FIGS. 3 and 4, each of the three fourth openings 85 is respectively in front of and behind the corresponding cathode-side fuel discharge port 75, cathode-side coolant discharge port 76, and cathode-side oxygen supply port 77. The cathode side fuel discharge port 75, the cathode side cooling medium discharge port 76, and the cathode side oxygen supply port 77 are arranged adjacent to each other so as to communicate with each other in the direction. The two second openings 69 are adjacent to each other so as to communicate with each other in the front-rear direction.

  Such unit cells 45 are stacked in the front-rear direction as shown in FIGS. 3 and 4 to form a cell stack 10.

  As shown in FIG. 3 (b), the cell stack 10 has a fuel supply path 88 for supplying liquid fuel to the anode electrode 51 of each unit cell 45, and liquid fuel from the anode electrode 51 of each unit cell 45. A fuel discharge path 90 for discharging is formed.

  The fuel supply path 88 is formed at the lower right end of the cell stack 10 so as to penetrate (pass) the plurality of unit cells 45 in the front-rear direction. Specifically, the fuel supply path 88 is formed by the cathode-side fuel supply port 72, the third opening 84, the first opening 68, and the anode-side fuel supply port 55 of each unit cell 45 communicating with each other in the front-rear direction. ing.

  The fuel discharge path 90 is formed at the upper left end of the cell stack 10 so as to penetrate (pass) the plurality of unit cells 45 in the front-rear direction. Specifically, the fuel discharge path 90 is formed by the anode-side fuel discharge port 58, the second opening 69, the fourth opening 85, and the cathode-side fuel discharge port 75 of each unit cell 45 communicating with each other in the front-rear direction. ing.

  Further, the fuel supply path 88 and the fuel discharge path 90 communicate with each other via two upper and lower fuel through holes 65 and a fuel flow path 62 of each unit cell 45.

  Further, as shown in FIG. 4B, the cell stack 10 is exhausted from an oxygen supply path 91 for supplying oxygen to the cathode electrode 52 of each unit cell 45 and the cathode electrode 52 of each unit cell 45. An exhaust passage 89 is formed.

  The oxygen supply path 91 is formed at the upper right end portion of the cell stack 10 so as to penetrate (pass) the plurality of unit cells 45 in the front-rear direction. Specifically, the oxygen supply path 91 is formed by the cathode side oxygen supply port 77, the fourth opening 85, the second opening 69, and the anode side oxygen supply port 60 of each unit cell 45 communicating with each other in the front-rear direction. ing.

  The exhaust path 89 is formed at the lower left end of the cell stack 10 so as to penetrate (pass) the plurality of unit cells 45 in the front-rear direction. Specifically, the exhaust path 89 is formed by the anode-side exhaust port 57, the first opening 68, the third opening 84, and the cathode-side exhaust port 74 of each unit cell 45 communicating with each other in the front-rear direction.

  Further, the oxygen supply path 91 and the exhaust path 89 communicate with each other via two upper and lower oxygen through holes 81 and an oxygen flow path 79 of each unit cell 45.

  Although not shown, the cell stack 10 includes a cooling medium supply path for supplying a cooling medium to the first cooling medium flow path 63 and the second cooling medium flow path 78 of each unit cell 45, and each unit cell 45. The cooling medium discharge path for discharging the cooling medium from the first cooling medium flow path 63 and the second cooling medium flow path 78 is formed.

  The cooling medium supply path (not shown) is formed so as to penetrate (pass) the plurality of unit cells 45 in the front-rear direction at the center in the left-right direction at the lower end of the cell stack 10. Specifically, the cooling medium supply path (not shown) includes a cathode side cooling medium supply port 73, a third opening 84, a first opening 68, and an anode side cooling medium of each unit cell 45 as shown in FIG. The supply ports 56 are formed by communicating with each other in the front-rear direction. The cooling medium discharge path (not shown) is formed to penetrate (pass) the plurality of unit cells 45 in the front-rear direction at the center in the left-right direction at the upper end of the cell stack 10. Specifically, the cooling medium discharge path (not shown) includes an anode side cooling medium discharge port 59, a second opening 69, a fourth opening 85, and a cathode side cooling medium discharge port 76 of each unit cell 45 in the front-rear direction. It is formed by communicating with each other.

  Further, the cooling medium supply path (not shown) and the cooling medium discharge path (not shown) communicate with each other via the first cooling medium flow path 63 and the second cooling medium flow path 78 of each unit cell 45. Yes.

  A seal member (not shown) is interposed between the anode-side separator body 53 and the cathode-side separator body 70 that are adjacent to each other in the front-rear direction. The seal member (not shown) includes at least the anode side fuel supply port 55 and the cathode side fuel supply port 72, the anode side fuel discharge port 58 and the cathode side fuel discharge port 75, the anode side oxygen supply port 60 and the cathode side. The oxygen supply port 77, the anode side exhaust port 57, and the cathode side exhaust port 74 are provided so as to surround the first cooling medium flow path 63 and the first cooling medium flow port 63 and the anode side cooling medium discharge port 59. 2 Allow the cooling medium to pass through the cooling medium flow path 78.

  The pair of covers 11 is formed in a substantially flat plate shape having a substantially rectangular shape when viewed from the front, and has the same size as each of the anode separator 47 and the cathode separator body 70.

  In addition, as shown in FIG. 2, six through holes 98 are formed in the front cover 11, and a fuel supply unit 92, a cooling medium supply unit 93, an exhaust unit 94, and a fuel discharge unit 97 are formed. Further, a cooling medium discharge unit 96 and an oxygen supply unit 95 are provided.

  Three through holes 98 are formed in each of the upper part and the lower part of the front cover 11. Specifically, the through holes 98 formed in the upper portion of the front cover 11 are respectively an oxygen supply path 91, a cooling medium discharge path (not shown), and a fuel discharge path 90 in order from the right side to the left side. And are spaced apart from each other in the left-right direction (see FIGS. 3 and 4).

  Further, the through holes 98 formed in the lower portion of the front cover 11 correspond to the fuel supply path 88, the cooling medium supply path (not shown), and the exhaust path 89 in order from the right side to the left side. And are spaced apart from each other in the left-right direction (see FIGS. 3 and 4). Each through hole 98 is formed in a substantially circular shape when viewed from the front, and is formed so as to penetrate the cover 11 in the front-rear direction.

  The fuel supply unit 92 is provided to supply liquid fuel to the unit cell 45 and is formed in a substantially cylindrical shape extending in the front-rear direction. Further, as shown in FIG. 3B, the fuel supply portion 92 has its rear end portion fitted into the lower right through hole 98 so that its internal space communicates with the lower end portion of the fuel supply path 88. Thus, it is arranged at the lower right end of the front cover 11.

  As shown in FIG. 2, the cooling medium supply unit 93 is provided to supply a cooling medium to the unit cell 45 and is formed in a substantially cylindrical shape extending in the front-rear direction. Further, the cooling medium supply section 93 has a rear end thereof fitted into the lower center through hole 98, so that the inner space thereof communicates with a cooling medium supply path (not shown). It is arrange | positioned in the center of the left-right direction of the lower end part.

  The exhaust part 94 is provided to discharge oxygen from the unit cell 45 and is formed in a substantially cylindrical shape extending in the front-rear direction. In addition, as shown in FIG. 4B, the exhaust portion 94 is inserted into the lower left through hole 98 so that the internal space thereof communicates with the lower end portion of the exhaust passage 89. It is arranged at the lower left end of the front cover 11.

  As shown in FIG. 2, the fuel discharge portion 97 is provided to discharge fuel from the unit cell 45, and is formed in a substantially cylindrical shape extending in the front-rear direction. Further, as shown in FIG. 3B, the rear end portion of the fuel discharge portion 97 is inserted into the upper left through hole 98 so that the inner space thereof communicates with the upper end portion of the fuel discharge passage 90. Further, it is disposed at the upper left end of the front cover 11.

  As shown in FIG. 2, the cooling medium discharge unit 96 is provided to discharge the cooling medium from the unit cell 45 and is formed in a substantially cylindrical shape extending in the front-rear direction. Further, the cooling medium discharge portion 96 has a rear end portion fitted into the upper center through hole 98 so that the internal space thereof communicates with a cooling medium discharge path (not shown). It is arrange | positioned in the center of the left-right direction of an upper end part.

  The oxygen supply unit 95 is provided to supply oxygen to the unit cell 45, and is formed in a substantially cylindrical shape extending in the front-rear direction. Further, as shown in FIG. 4B, the oxygen supply unit 95 has its rear end portion fitted into the upper right side through hole 98 so that the internal space communicates with the upper end portion of the oxygen supply path 91. Yes.

  A seal member (not shown) is interposed between the front cover 11 and the cathode separator body 70 adjacent thereto. The seal member (not shown) is provided so as to surround at least the cathode side fuel supply port 72, the cathode side exhaust port 74, the cathode side fuel discharge port 75, and the cathode side oxygen supply port 77, and the cathode side cooling medium supply port 73 allows the cooling medium to pass through the second cooling medium flow path 78.

  A seal member (not shown) is interposed between the rear cover 11 and the anode separator body 53 adjacent thereto. The seal member (not shown) is provided so as to surround at least the anode side fuel supply port 55, the anode side exhaust port 57, the anode side oxygen supply port 60, and the anode side fuel discharge port 58, and the anode side cooling medium supply port 56 allows the cooling medium to pass through the first cooling medium flow path 63.

  Further, as shown in FIGS. 3B and 4B, the fuel cell 3 includes three insert members 100 corresponding to the fuel discharge passage 90, the fuel supply passage 88, and the exhaust passage 89, respectively. Is provided. The insert member 100 provided in the fuel discharge path 90 corresponds as an example of the first guide member, and the insert member 100 provided in the fuel supply path 88 corresponds as an example of the second guide member, and corresponds to the exhaust path 89. The provided insert member 100 corresponds as an example of a third guide member.

  Each of the three insert members 100 has the same structure. Therefore, in the following description of the insert member 100, the insert member 100 provided in the fuel discharge path 90 is taken up, the configuration thereof is described, and the insert member 100 provided in each of the fuel discharge path 90 and the exhaust path 89 is described. Omitted.

  As shown in FIG. 5, the insert member 100 is configured as a separate member from the anode-side separator 47 and the cathode-side separator 48, and is formed from an insulating resin material such as engineering plastic. The insert member 100 is formed in a substantially wedge shape in a side view that tapers toward the front, and is flattened in the left-right direction.

  Specifically, the insert member 100 includes a horizontal surface 102 that is an upper surface thereof, a vertical surface 103 that is a rear surface thereof, and an inclined surface 101 as an example of a bubble guide portion that is a lower surface thereof.

  The horizontal plane 102 is formed in a substantially rectangular shape in plan view extending in the front-rear direction. Further, the horizontal plane 102 has a length in the front-rear left-right direction substantially the same as the length of the fuel discharge passage 90 in the front-rear left-right direction.

  The vertical surface 103 is formed in a substantially rectangular shape in rear view extending continuously downward from the rear end portion of the horizontal plane 102 and extending downward. Further, as shown in FIG. 3B, the vertical surface 103 is formed such that its vertical length is shorter than the vertical length of the fuel discharge passage 90.

  The inclined surface 101 is formed as a smooth surface that extends from the lower end of the vertical surface 103 toward the front end of the horizontal plane 102 and extends upward in the front direction.

  In the insert member 100 provided in the fuel discharge path 90, the horizontal surface 102 is the upper end surface of the fuel discharge path 90 (the anode side fuel discharge port 58, the second opening 69, the fourth opening 85, and the cathode side fuel discharge port 75. The vertical surface 103 is fixed to the front surface of the rear cover 11, and is fixed to the upper end portion in the fuel discharge path 90.

  Thereby, the inclined surface 101 of the insert member 100 provided in the fuel discharge path 90 is formed so as to be inclined upward in the vertical direction from the lower end portion of the vertical surface 103 to the front. The front side is positioned above the rear side of the inclined surface 101 in the vertical direction. Further, the front end portion of the insert member 100 provided in the fuel discharge passage 90 is disposed adjacent to the rear side of the rear end portion of the fuel discharge portion 97.

  Further, in the insert member 100 provided in the fuel supply path 88, the horizontal plane 102 is the lower end surface of the fuel supply path 88 (cathode side fuel supply port 72, third opening portion 84, first opening portion 68 and anode side fuel supply port 55. The vertical surface 103 is fixed to the front surface of the rear cover 11, and is fixed to the lower end portion in the fuel supply path 88.

  Accordingly, the inclined surface 101 of the insert member 100 provided in the fuel supply path 88 is formed to be inclined downward in the vertical direction from the upper end portion of the vertical surface 103 toward the front. The front side is located below the rear side of the inclined surface 101 in the vertical direction. Further, the front end portion of the insert member 100 provided in the fuel supply path 88 is disposed adjacent to the rear side of the rear end portion of the fuel supply portion 92. In addition, the inclined surface 101 of the insert member 100 provided in the fuel supply path 88 corresponds as an example of the first drainage guide portion.

  Further, as shown in FIG. 4B, the insert member 100 provided in the exhaust passage 89 has a horizontal plane 102 whose bottom surface is the lower end surface of the exhaust passage 89 (the anode side exhaust port 57, the first opening 68, and the third opening 84. In addition, the vertical surface 103 is fixed to the front surface of the rear cover 11 so as to be fixed to the lower end portion in the exhaust passage 89.

  Thereby, the inclined surface 101 of the insert member 100 provided in the exhaust path 89 is formed so as to be inclined downward in the vertical direction from the upper end portion of the vertical surface 103 to the front. The front side is located on the lower side in the vertical direction than the rear side of the inclined surface 101. Further, the front end portion of the insert member 100 provided in the exhaust passage 89 is disposed adjacent to the rear side of the rear end portion of the exhaust portion 94. In addition, the inclined surface 101 of the insert member 100 provided in the exhaust path 89 corresponds as an example of the second drainage guide portion.

  In addition, the space secured in each of the fuel supply path 88, the fuel discharge path 90, and the exhaust path 89 is formed so that the cross-sectional area when cut in the vertical direction decreases toward the rear.

Further, the fuel cell 3 is further provided with a current collector plate (not shown) formed of a conductive material, and the fuel cell 3 generated from a terminal provided on the current collector plate (not shown). It is comprised so that electric power can be taken out outside.
3. Power Generation Operation Next, power generation in the electric vehicle 1 will be described.

  In the electric vehicle 1, as shown in FIG. 1, during the power generation operation, first, the fuel supply valve 21, the gas discharge valve 23, the air supply valve 29, and the air discharge valve 30 are opened by a control signal from the control unit 34. At the same time, the first fuel transport pump 19, the second fuel transport pump 20, and the air supply pump 28 are driven.

  Then, the liquid fuel stored in the fuel tank 15 is driven to the fuel supply unit 92 shown in FIG. 6A via the fuel supply pipe 17 by driving the first fuel transport pump 19 and the second fuel transport pump 20. Supplied. Further, by driving the air supply pump 28, oxygen, specifically, air is taken into the air supply pipe 26 from the outside of the electric vehicle 1, and the air passes through the air supply pipe 26 as shown in FIG. The oxygen supply unit 95 shown in FIG.

  Further, although not shown, a cooling medium (for example, water) is supplied to the cooling medium supply unit 93 via a cooling medium supply pipe (not shown).

  As shown in FIG. 6A, the liquid fuel supplied to the fuel supply unit 92 enters the fuel supply path 88 via the fuel supply unit 92 along the supply direction X (direction from the front side to the rear side). Supplied. Then, the liquid fuel supplied into the fuel supply path 88 is moved along the inclination of the inclined surface 101 of the insert member 100, passes through the cathode side fuel supply port 72 of each unit cell 45, and passes through the anode side fuel supply port 72. 55 is reached.

  Then, as indicated by arrows, the liquid fuel is supplied to each fuel through-hole 65 by the flow pressure of the liquid fuel, and then passes through each fuel through-hole 65 to each fuel flow path 62 (fuel flow It is supplied to the lower end of the path forming area A1).

  At this time, since the space secured in the fuel supply path 88 is formed by the insert member 100 so as to decrease toward the rear, the rear side of the fuel supply path 88 relatively far from the fuel supply section 92 is formed. Also in the portion, the flow rate of the liquid fuel can be ensured. Therefore, the flow pressure of the liquid fuel can be kept constant in the fuel supply path 88.

  Further, the liquid fuel supplied to the fuel flow path 62 is moved upward along the fuel flow path 62 while coming into contact with the rear surface of the anode-side diffusion layer 66 and reaches the upper fuel through hole 65. .

  Then, as shown by the arrows, the liquid fuel passes through each fuel through hole 65, is discharged to each anode side fuel discharge port 58, and reaches the fuel discharge path 90. Then, the liquid fuel that has reached the fuel discharge path 90 is moved along the discharge direction Y (the direction from the rear side to the front side), passes through each cathode-side fuel discharge port 75, and is discharged from the fuel discharge portion 97. .

  Further, as shown in FIG. 6B, the air supplied to the oxygen supply unit 95 is supplied to the oxygen supply path 91 via the oxygen supply unit 95 in the supply direction X (direction from the front side to the rear side). Supplied along. The air supplied into the oxygen supply path 91 passes through the anode side oxygen supply port 60 of each unit cell 45 and reaches the cathode side oxygen supply port 77.

  Then, as indicated by the arrows, the air is supplied to each oxygen through hole 81 and then passes through each oxygen through hole 81 to each oxygen channel 79 (oxygen channel forming region (not shown)). ).

  Then, the air supplied to the oxygen channel 79 is moved downward along the oxygen channel 79 while contacting the front surface of the cathode side diffusion layer 82 and reaches the lower oxygen through hole 81. .

  Then, as shown by arrows, the air passes through each oxygen through hole 81, is discharged to each cathode side exhaust port 74, and reaches the exhaust path 89. Then, the air that has reached the exhaust path 89 is moved along the discharge direction Y (the direction from the rear side to the front side), passes through the anode side exhaust ports 57, and is discharged from the exhaust unit 94.

  Then, as described above, the liquid fuel flowing in the fuel flow path 62 is supplied to the anode electrode 51 via the anode side diffusion layer 66 as shown in FIGS. 2 and 6A. Further, as described above, oxygen in the air flowing in the oxygen flow path 79 is supplied to the cathode electrode 52 via the cathode side diffusion layer 82 as shown in FIGS. 2 and 6B.

At this time, when the liquid fuel is methanol, in each unit cell 45, as shown in FIG. 2 and FIG. That is, in the anode electrode 51 supplied with methanol, methanol (CH ₃ OH) reacts with hydroxide ions (OH ⁻ ) generated by a reaction (described later) at the cathode electrode 52 to generate carbon dioxide (CO ₂ ) And water (H ₂ O) are generated, and electrons (e ⁻ ) are generated (see the following reaction formula (1)).

The electrons (e ⁻ ) generated at the anode electrode 51 are supplied to the cathode electrode 52 via an external circuit (not shown). Further, the generated water (H ₂ O) moves from the anode electrode 51 to the cathode electrode 52 through the electrolyte layer 50.

In the cathode electrode 52, electrons (e ⁻ ), water (H ₂ O), and oxygen (O ₂ ) in the supplied air react to generate hydroxide ions (OH ⁻ ). (See the following reaction formula (2).) The generated hydroxide ions (OH ⁻ ) move from the cathode electrode 52 to the anode electrode 51 through the electrolyte layer 50 made of an anion exchange membrane.

In such an anode electrode 51 and a cathode electrode 52, an electrochemical reaction occurs continuously, and a reaction represented by the following reaction formula (3) occurs in each unit cell 45 as a whole. Thereby, in the fuel cell 3, an electromotive force is generated and electric power is generated.
(1) CH ₃ OH + 6OH ⁻ → CO ₂ + 5H ₂ O + 6e ⁻ (reaction at the anode electrode 51)
(2) O ₂ + 2H ₂ O + 4e ⁻ → 4OH ⁻ (reaction at the cathode electrode 52)
(3) CH ₃ OH + 3 / 2O ₂ → CO ₂ + 2H ₂ O (reaction in the entire unit cell 45)
Further, when the liquid fuel is hydrazine, the reactions represented by the following reaction formulas (4) to (6) occur in each unit cell 45, and the fuel cell 3 generates power.
(4) N ₂ H ₄ + 4OH ⁻ → N ₂ + 4H ₂ O + 4e ⁻ (reaction at the anode electrode 51)
(5) O ₂ + 2H ₂ O + 4e ⁻ → 4OH ⁻ (reaction at the cathode electrode 52)
(6) N ₂ H ₄ + O ₂ → N ₂ + 2H ₂ O (reaction in the entire unit cell 45)
In the power generation described above, CO ₂ gas or N ₂ gas may be generated at the anode electrode 51 and may stay as bubbles B in the liquid fuel in the fuel flow path 62.

  As shown in FIG. 6A, such a bubble B is moved upward by the upward buoyant action and the upward flow of the liquid fuel, and passes through the upper fuel through hole 65. It passes through and is moved into the fuel discharge path 90. Furthermore, the bubbles B that have reached the fuel discharge path 90 reach the inclined surface 101 of the insert member 100 by buoyancy.

  Then, the bubbles B that have reached the inclined surface 101 are guided toward the fuel discharge portion 97 along the inclination of the inclined surface 101 and are discharged from the fuel discharge portion 97 to the outside of the fuel cell 3 together with the liquid fuel.

Further, the cooling medium supplied to the cooling medium supply unit 93 is supplied to the cooling medium supply path (not shown) via the cooling medium supply unit 93, and further, as shown in FIG. The first coolant flow path 63 and the second coolant flow path 78 are supplied. Then, after the cooling medium supplied to the first cooling medium flow path 63 and the second cooling medium flow path 78 passes through the first cooling medium flow path 63 and the second cooling medium flow path 78 from the lower side to the upper side, It reaches a cooling medium discharge path (not shown), and is discharged out of the fuel cell 3 from the cooling medium discharge unit 96. Thereby, each unit cell 45 is cooled to a predetermined temperature (for example, −30 to 120 ° C.).
4). Removal Operation of Crossover Liquid Fuel In the fuel cell 3, when the liquid fuel permeates the membrane electrode assembly 46 from the anode electrode 51 side to the cathode electrode 52 side, so-called crossover may occur.

  As shown in FIG. 6B, the crossed over liquid fuel passes through the oxygen through hole 81 and falls into the exhaust passage 89 from the lower end of the oxygen passage 79 due to the flow of gravity and air. .

  The liquid fuel that has fallen into the exhaust passage 89 reaches the inclined surface 101 of the insert member 100 by gravity. Then, the liquid fuel that has reached the inclined surface 101 is moved forward and downward along the inclination of the inclined surface 101, and is discharged from the exhaust unit 94 to the outside of the fuel cell 3 together with air.

Further, as shown in FIG. 1, the liquid fuel discharged out of the fuel cell 3 reaches the fuel recovery unit 31 via the air discharge pipe 27 and is recovered in the fuel recovery unit 31. Thus, the operation of removing the crossed over liquid fuel is completed.
5. Maintenance operation of the fuel cell In the fuel cell 3, during maintenance, the liquid fuel in the fuel cell 3 is discharged out of the fuel cell 3 from the viewpoint of electric shock prevention. In such a case, the liquid fuel in the fuel cell 3 is discharged from the fuel supply unit 92.

  As shown in FIG. 6A, gravity acts on the liquid fuel in the fuel cell 3, and the liquid fuel in the fuel supply path 88 is moved along the inclined surface 101 of the insert member 100. The fuel is discharged from the fuel supply unit 92 to the outside of the fuel cell 3.

  The liquid fuel in the fuel discharge path 90 and the fuel flow path 62 is sequentially moved to the fuel supply path 88 by gravity as the liquid fuel in the fuel supply path 88 is discharged.

The fuel cell 3 is maintained in a state where all the liquid fuel in the fuel cell 3 is discharged.
6). Action and Effect In the fuel cell 3, as shown in FIG. 6A, the cell stack 10 is formed with a fuel supply path 88 and a fuel discharge path 90. Therefore, liquid fuel can be reliably supplied to and discharged from each unit cell 45 of the cell stack 10 via the fuel supply path 88 and the fuel discharge path 90, and power can be generated in each unit cell 45.

  Further, the bubbles B in the liquid fuel generated by the power generation are moved into the fuel discharge path 90 along with the flow of the liquid fuel, and further, the upper end portion of the fuel discharge path 90 by buoyancy in the fuel discharge path 90. That is, it reaches the inclined surface 101 of the insert member 100 provided in the fuel discharge path 90.

  The inclined surface 101 of the insert member 100 provided in the fuel discharge path 90 is formed such that the front side (downstream side in the discharge direction Y) is located above the rear side (upstream side in the discharge direction Y). Therefore, the bubbles B that have reached the inclined surface 101 are guided by the inclined surface 101 from the upstream side to the downstream side in the discharge direction Y, and further, the fuel cell 3 together with the liquid fuel via the fuel discharge unit 97. It is discharged from the inside.

  As a result, according to the fuel cell 3, it is possible to suppress the bubbles B from staying in the liquid fuel in the fuel cell 3, and to suppress a decrease in output.

  Further, the inclined surface 101 of the insert member 100 provided in the fuel discharge path 90 is formed to be inclined upward as it goes to the front side (downstream side in the discharge direction Y).

  Therefore, the bubbles B that have reached the inclined surface 101 are moved from the rear side (upstream side in the discharge direction Y) toward the front side (downstream side) along the inclination of the inclined surface 101. That is, the inclined surface 101 can reliably guide the bubbles B that have reached the inclined surface 101 toward the downstream side in the discharge direction Y.

  As a result, it is possible to reliably suppress the bubbles B from staying in the liquid fuel in the fuel cell 3, and to reliably suppress a decrease in the output of the fuel cell 3.

  Each unit cell 45 includes a membrane electrode assembly 46, an anode separator 47 and a cathode separator 48, as shown in FIG. Therefore, while the power can be generated in each membrane electrode assembly 46, the anode-side separator 47 and the cathode-side separator 48 reliably prevent the membrane electrode assemblies 46 of the unit cells 45 adjacent to each other from being short-circuited. it can. As a result, the power generation efficiency of the fuel cell 3 can be improved.

  Further, in the cell stack 10, as shown in FIG. 3B, the fuel discharge passage 90 is formed by the anode side fuel discharge port 58 and the cathode side fuel discharge port 75 communicating with each other in the front-rear direction. An insert member 100 is provided in the fuel discharge path 90.

  Therefore, the inclined surface 101 of the insert member 100 can be formed smoothly while having a simple configuration. As a result, the power generation efficiency of the fuel cell 3 can be improved, and the discharge of the bubbles B from the fuel cell 3 can be facilitated.

  In the fuel cell 3, since the insert member 100 is provided in the fuel discharge path 90, the cell stack 10 can be prevented from being deformed even when the number of unit cells 45 is increased.

  Therefore, the retention of the bubbles B in the fuel discharge path 90 can be reliably suppressed, and liquid fuel can be prevented from remaining in each of the fuel supply path 88 and the fuel discharge path 90 during the maintenance of the fuel cell 3. The maintenance property of the battery 3 can be improved. That is, the maintainability of the fuel cell 3 can be improved while the output power can be improved.

  Further, in the fuel cell 3, the insert member 100 is provided at the lower end portion in the fuel supply path 88, and the inclined surface 101 of the insert member 100 is on the rear side of the front side (upstream side in the supply direction X). It is formed so that (the downstream side in the discharge direction Y) is located on the upper side. More specifically, the inclined surface 101 of the insert member 100 provided in the fuel supply path 88 is formed to be inclined upward as it goes to the rear side (downstream side in the supply direction X).

  Therefore, during maintenance of the fuel cell 3, the liquid fuel is guided toward the downstream side in the supply direction X along the inclination of the inclined surface 101 in the fuel supply path 88. Therefore, the liquid fuel in the fuel cell 3 can be reliably discharged from the fuel cell 3 to the outside of the fuel cell 3. As a result, it is possible to further improve the maintainability of the fuel cell 3.

  In the fuel cell 3, since the inclined surface 101 in the fuel supply path 88 is formed by the insert member 100, the inclined surface 101 can be formed smoothly.

  Therefore, it is possible to suppress the liquid fuel from remaining in the fuel supply path 88 during maintenance of the fuel cell 3 with a simple configuration, and to facilitate the discharge of the liquid fuel from the fuel cell 3. it can.

  Further, since the insert member 100 is provided in the fuel supply path 88, it is possible to reliably suppress the cell stack 10 from being deformed even if the number of unit cells 45 is increased. That is, it is possible to further improve the maintainability of the fuel cell 3 while improving the output power.

  Further, as shown in FIG. 6B, an oxygen supply path 91 and an exhaust path 89 are formed in the cell stack 10. Therefore, air (oxygen) can be reliably supplied to and discharged from each unit cell 45. As a result, the power generation efficiency of each unit cell 45 can be improved, and consequently the power generation efficiency of the fuel cell 3 can be improved.

  In the fuel cell 3, there may be a crossover in which the liquid fuel passes through the membrane electrode assembly 46. In such a case, the liquid fuel that has crossed over is moved into the exhaust passage 89 with the flow of air (oxygen), and is applied to the lower end portion of the exhaust passage 89, that is, the inclined surface 101 of the insert member 100 by gravity. To reach.

  Then, the liquid fuel that has reached the inclined surface 101 of the insert member 100 in the exhaust passage 89 is guided toward the front side (downstream in the discharge direction Y) by the inclined surface 101 and is discharged from the fuel cell 3.

  Therefore, the crossover liquid fuel can be smoothly discharged from the fuel cell 3, and the crossover liquid fuel can be inhibited from inhibiting the supply of oxygen to the cathode electrode 52. As a result, a decrease in the electromotive force of the fuel cell 3 can be suppressed.

  Further, the inclined surface 101 of the insert member 100 in the exhaust passage 89 is formed so as to be inclined downward as it goes to the downstream side of the front side (discharge direction Y). Therefore, the crossed over liquid fuel is moved from the rear side toward the front side along the inclination of the inclined surface 101. That is, the inclined surface 101 of the insert member 100 in the exhaust passage 89 can reliably guide the crossed over liquid fuel toward the downstream side in the discharge direction Y.

  Therefore, the liquid fuel that has crossed over can be discharged more smoothly from within the fuel cell 3, and a reduction in the electromotive force of the fuel cell 3 can be reliably suppressed.

  In the fuel cell 3, the insert member 100 is provided in the exhaust passage 89. Therefore, the inclined surface 101 of the insert member 100 in the exhaust passage 89 can be formed smoothly while having a simple configuration, and the crossover liquid fuel can be discharged more smoothly from the fuel cell 3. it can.

  Moreover, since the insert member 100 in the exhaust path 89 is provided, even if the number of unit cells 45 is increased, the cell stack 10 can be further reliably prevented from being deformed.

That is, it is possible to further reliably suppress a decrease in the electromotive force of the fuel cell 3 while improving the output power.
7). Second Embodiment A second embodiment of the present invention will be described with reference to FIG. In the second embodiment, members similar to those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In the first embodiment described above, as shown in FIG. 3B, the insert member 100 is provided in each of the fuel discharge passage 90 and the fuel supply passage 88, and the inclined surface 101 of the insert member 100 provided in the fuel discharge passage 90. However, it functions as an example of the bubble guide part, and the inclined surface 101 of the insert member 100 provided in the fuel supply path 88 functions as an example of the first drainage guide part.

  On the other hand, in the second embodiment, the insert member 100 is not provided in each of the fuel discharge path 90 and the fuel supply path 88. In the fuel discharge path 90, the anode side fuel discharge port of each unit cell 45 is provided. 58, the second opening 69, the fourth opening 85, and the upper edge of the cathode side fuel discharge port 75 (hereinafter referred to as the first edge 110) form the bubble guide 105, and in the fuel supply path 88. The lower end edge (hereinafter referred to as the second end edge 111) of the cathode side fuel supply port 72, the third opening 84, the first opening 68 and the anode side fuel supply port 55 of each unit cell 45 is the first. One drainage guide portion 106 is formed.

  That is, the bubble guide part 105 is formed from a plurality of first edges 110 corresponding to the plurality of unit cells 45, and the first drainage guide part 106 is a plurality of second edges corresponding to the plurality of unit cells 45. 111.

  Specifically, the bubble guide portion 105 is provided so as to form a plurality of steps that gradually decrease from the front side toward the rear side. In the unit cells 45 adjacent to each other, One end edge 110 is provided so as to be positioned below the first end edge 110 of the front unit cell 45. Therefore, the bubble guide part 105 is formed so that the downstream side is positioned higher than the upstream side in the discharge direction Y.

  Further, in the unit cells 45 adjacent to each other, the vertical lengths of the anode-side fuel discharge port 58, the second opening 69, the fourth opening 85, and the cathode-side fuel discharge port 75 of the rear unit cell 45 are the front side. Are formed so as to be shorter than the vertical lengths of the anode-side fuel discharge port 58, the second opening 69, the fourth opening 85, and the cathode-side fuel discharge port 75 of the unit cell 45.

  Moreover, the 1st drainage guide part 106 is formed in the substantially step shape so that the some level | step difference which becomes high gradually may be formed as it goes to the back side from the front side. The first drainage guide unit 106 is configured such that, in the unit cells 45 adjacent to each other, the second edge 111 of the front unit cell 45 is positioned below the second edge 111 of the rear unit cell 45. Is provided. Therefore, the first drainage guide part 106 is formed so that the downstream side is positioned higher than the upstream side in the supply direction X.

  Further, in the unit cells 45 adjacent to each other, the vertical lengths of the cathode side fuel supply port 72, the third opening 84, the first opening 68 and the anode side fuel supply port 55 of the front unit cell 45 are the rear side. The unit cell 45 is formed so as to be longer than the vertical lengths of the cathode side fuel supply port 72, the third opening 84, the first opening 68 and the anode side fuel supply port 55.

  Although not shown, in the exhaust passage 89, the lower edge of the anode side exhaust port 57, the first opening portion 68, the third opening portion 84, and the cathode side exhaust port 74 of each unit cell 45 is the second drainage guide. Part (not shown). Note that the second drainage guide portion (not shown) is also formed in a substantially staircase shape similar to the first drainage guide portion 106.

In the second embodiment as described above, the same effects as those in the first embodiment can be obtained.
8). In the second embodiment, the insert member 100 is not provided in the fuel discharge path 90, and the bubble guide portion 105 is formed from the plurality of first end edges 110. More specifically, in the second embodiment, the first edge 110 of each unit cell 45 is formed so as to extend in the front-rear direction, and the bubble guide portion 105 gradually becomes lower from the front side toward the rear side. Are provided to form a plurality of steps.

  On the other hand, the first edge 110 of each unit cell 45 is formed so as to extend in the direction connecting the rear lower part and the front upper part, and the bubble guide part 105 composed of a plurality of first end edges 110 is moved forward. It can also be formed as an inclined surface that inclines upward as it goes.

  Also by this, the same operational effects as those of the first embodiment and the second embodiment can be obtained. Further, similarly to the first end edge 110, the second end edge 111 is formed so as to extend in a direction connecting the rear lower part and the front upper part, and the first drainage guide portion including the plurality of second end edges 111. 106 may be formed as an inclined surface that inclines toward the front.

  On the other hand, in the case where the insert member 100 is not provided and the bubble guide portion 105 is formed from the plurality of first end edges 110 as in the second embodiment and the modified example, each member (anode separator body) 53, there is a limit to the smooth formation of the bubble guide portion 105 due to dimensional tolerances of the anode side seal 54, the cathode side seal 71, and the cathode side separator body 70).

  In this respect, in the first embodiment in which the insert member 100 is provided, the inclined surface 101 functions as an example of the bubble guide portion as compared with the case where the bubble guide portion 105 is formed from the plurality of first end edges 110. Can be formed smoothly.

  Therefore, the first embodiment can further facilitate the discharge of the bubbles B from the fuel cell 3 as compared with the second embodiment and the modification.

3 Fuel Cell 10 Cell Stack 45 Unit Cell 46 Membrane Electrode Assembly 47 Anode Side Separator 48 Cathode Side Separator 55 Anode Side Fuel Supply Port 58 Anode Side Fuel Discharge Port 68 First Opening 69 Second Opening 72 72 Cathode Side Fuel Supply Port 75 Cathode side fuel outlet 84 Third opening 85 Fourth opening 88 Fuel supply path 89 Exhaust path 90 Fuel discharge path 91 Oxygen supply path 100 Insert member 101 Inclined surface 105 Bubble guide part 106 First drainage guide part X Supply Direction Y Discharge direction B Bubble

Claims (4)

A laminated structure formed by laminating a plurality of unit cells in the horizontal direction,
The laminated structure is
A fuel supply path that passes through the plurality of unit cells in the stacking direction of the plurality of unit cells and supplies liquid fuel to each of the plurality of unit cells;
A fuel discharge path for discharging liquid fuel from each of the plurality of unit cells, passing through the plurality of unit cells in the stacking direction,
At the upper end of the fuel discharge path in the vertical direction,
A fuel cell comprising a bubble guide portion formed such that a downstream side in the discharge direction is positioned on an upper side in a vertical direction with respect to an upstream side in a discharge direction of the liquid fuel. The bubble guide is
2. The fuel cell according to claim 1, wherein the fuel cell is formed so as to be inclined upward in the vertical direction toward the downstream side in the discharge direction. Each of the plurality of unit cells is
A membrane electrode assembly;
A pair of separators arranged opposite to each other in the stacking direction so as to sandwich the membrane electrode assembly,
The pair of separators includes
A fuel supply port through which liquid fuel to be supplied to the unit cell passes;
A fuel discharge port through which liquid fuel discharged from the unit cell passes,
The fuel supply path is
The plurality of unit cells are stacked, and the plurality of fuel supply ports are formed by communicating with each other in the stacking direction,
The fuel discharge path is
The plurality of unit cells are stacked, and the plurality of fuel discharge ports are formed by communicating with each other in the stacking direction,
The bubble guide is
3. The fuel cell according to claim 1, wherein the fuel cell is configured as a separate member from the separator and is formed by a first guide member provided in the fuel discharge path. 4. The laminated structure is
An oxygen supply path for passing oxygen through the plurality of unit cells in the stacking direction of the plurality of unit cells and supplying oxygen to each of the plurality of unit cells;
An exhaust path for passing through the plurality of unit cells in the stacking direction and exhausting from each of the plurality of unit cells;
At the lower end of the fuel supply path in the vertical direction,
A first drainage guide portion formed so that the downstream side in the supply direction is positioned on the upper side in the vertical direction from the upstream side in the supply direction of the liquid fuel;
At the lower end in the vertical direction of the exhaust path,
The second drainage guide portion formed so that the downstream side in the discharge direction is located below the vertical direction with respect to the upstream side in the discharge direction is provided. Fuel cell.

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