JP2007191060A - In-vehicle fuel cell system - Google Patents

Abstract

The present invention relates to an in-vehicle fuel cell capable of efficiently recovering and utilizing water contained in an outlet gas when liquid water condensed by outlet gas cooling is recovered and used for operation of a fuel cell. The purpose is to provide a system.
A vehicle-mounted fuel cell system according to the present invention is characterized in that a capacitor is disposed in an upper part of a vehicle front compartment. According to the present invention, the condenser 4 of the fuel cell system is arranged in the upper part of the front compartment 2 of the vehicle and, for example, the cooling air is guided to the condenser 4 from the air guide hole 8 provided in the bonnet hood 7. Compatibility with other heat exchange systems such as radiators to be installed is easy. In addition, by separating the installation locations of the condenser 4 and other heat exchange systems, sufficient cooling efficiency can be achieved without reducing the effective cooling area of each.
[Selection] Figure 1

Description

  The present invention relates to an in-vehicle fuel cell system in which fuel cell outlet gas is cooled by a condenser, and liquid water condensed by outlet gas cooling is recovered and used for operation of the fuel cell.

  A fuel cell system is a device that directly converts the energy of fuel into electrical energy. In a fuel cell system, a fuel gas containing hydrogen is supplied to one anode of a pair of electrodes provided with an electrolyte membrane interposed therebetween, and an oxygen agent gas containing oxygen is supplied to the other cathode. At this time, electrical energy can be extracted from the electrodes by utilizing the following electrochemical reaction that occurs on the electrolyte membrane side surface of the pair of electrodes. (Described in [Patent Document 1] below).

Anode reaction: H ₂ → 2H ⁺ + 2e ⁻ (1)
Cathode reaction: 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O (2)
JP, 8-106914, A As a supply method of fuel gas to an anode, a method of supplying hydrogen gas directly from a hydrogen storage device, a method of supplying hydrogen-containing gas which reformed fuel containing hydrogen, etc. are known. ing. As the fuel containing hydrogen, natural gas, methanol, gasoline, and the like are conceivable. Air is generally used as the oxygen agent gas supplied to the cathode. In addition, hydrogen ions H + (protons) move in the electrolyte membrane. At this time, moisture needs to be present in the electrolyte membrane (the electrolyte membrane needs to be humidified). Moreover, since the heat resistance of the electrolyte membrane is limited, it needs to be cooled, and water is also used in this case. Thus, water is used when the fuel cell is operated.

  As a method for securing water used for the operation of the fuel cell, there is a method for liquefying and recovering water vapor present in the exhaust gas of the fuel cell. In order to liquefy and recover water vapor, a method of installing a condenser for liquefying water vapor in front of the vehicle where cooling air can be easily obtained or a method of liquefying water vapor using heat exchange with other cooling systems is adopted. It is common.

  However, in the method of installing a capacitor in front of the vehicle, there are air conditioning capacitors in addition to fuel cell capacitors, and other cooling system components such as radiators. Must be placed. For this reason, cooling efficiency becomes severe due to a decrease in cooling efficiency due to an increase in cooling wind pressure loss and difficulty in securing an effective cooling area. In addition, there is an aspect in which the cooling piping is extended due to the distance from the fuel cell main body being increased, resulting in difficulty in layout and an increase in weight due to the piping. Further, when the fuel cell capacitor is laid out in front of the vehicle, it is necessary to separate the gas and liquid at a portion having no height, or to pump up the gas and liquid separator using a pump.

  On the other hand, in the method using heat exchange of another cooling system, the degree of freedom of the installation position of the heat exchanger is increased, but it may be indirect cooling by another cooling system, so that sufficient cooling efficiency may not be ensured. There is an aspect. Accordingly, an object of the present invention is to efficiently recover the water contained in the outlet gas when the fuel cell outlet gas is cooled by the condenser and the liquid water condensed by the outlet gas cooling is recovered and used for the operation of the fuel cell. -To provide an in-vehicle fuel cell system that can be used.

  The in-vehicle fuel cell system of the present invention cools the fuel cell outlet gas with a condenser, collects the liquid water condensed by the outlet gas cooling, and uses it for the operation of the fuel cell. It is characterized by being arranged in the upper part of the compartment.

  According to the in-vehicle fuel cell system of the present invention, the condenser of the fuel cell system is arranged in the upper part of the front compartment of the vehicle such as the engine compartment, and the cooling air is guided to the condenser from the air guide hole provided in the hood hood, for example. Thus, it becomes easy to achieve compatibility with other heat exchange systems such as a radiator to be installed in front of the vehicle. In addition, by separating the installation locations of the fuel cell system condenser and another heat exchange system such as a radiator, it is possible to achieve sufficient cooling efficiency without reducing the effective cooling area of each.

  Hereinafter, specific embodiments of the fuel cell system of the present invention will be described with reference to the drawings. The fuel cell system in this embodiment supplies electric power to a motor as a vehicle drive source, and is mounted on the vehicle. FIG. 1 shows a system layout configuration diagram of the first embodiment of the present invention. As shown in FIG. 1, this system is disposed inside a vehicle front compartment 2 provided at the front of the vehicle 1. The vehicle front compartment 2 is a portion called an engine compartment (engine room) when an engine is mounted, and a portion called a motor room when a motor is mounted.

  This fuel cell system mainly cools a fuel cell main body 3 incorporating a fuel cell stack, a capacitor 4 which will be described in detail later, a gas-liquid separator 5 provided accompanying the capacitor 4, a fuel cell stack, and the like. Cooling system (radiator and its piping, etc .: not shown). Although the radiator is not shown, it is installed in the place where the normal radiator on the back of the bumper is installed. In addition, the capacitor 4 includes a capacitor fan 6 for forcibly introducing cooling air into the capacitor 4. Further, the hood hood 7 is provided with a cooling air introduction hole 8 for introducing cooling air into the condenser 4. A shutter 9 that closes the upper surface of the capacitor 4 is also provided.

  As described above, in the fuel cell, it is necessary to supply moisture to the electrolyte membrane in order to obtain good power generation efficiency. The capacitor 4 is installed to cool and liquefy water vapor contained in the outlet gas (exhaust gas) of the fuel cell and obtain water to be supplied to the electrolyte membrane. In the condenser 4, the outlet gas is cooled to liquefy the water vapor. However, what is discharged from the condenser 4 is not only the liquefied water, but the gas-liquid separator 5 described above is disposed on the downstream side of the condenser 4, and only the separated liquid water is the fuel cell. It is supplied to the main body 3. At this time, liquid water is sent to the fuel cell main body 3 by a pump 10 provided at the lower part of the gas-liquid separator 5.

  The capacitor 4 is mounted in an inclined state with the front side of the vehicle lowered in accordance with the inclination of the hood hood 7. And the gas-liquid separator 5 mentioned above is connected below the inclination lower part side. For this reason, the gas-liquid discharged | emitted from the capacitor | condenser 4 is introduce | transduced into the gas-liquid separator 5 via the introducing | transducing part 11, without using a pump. The fuel cell main body 3 is also disposed below the capacitor 4. For this reason, after the cooling air introduced from the cooling air introduction hole 8 is used for cooling the capacitor 4, it is used for cooling the fuel cell main body 3 below it. Further, the condenser fan 6 provided along with the condenser 4 is driven when sufficient cooling air cannot be obtained when the vehicle is stopped or traveling at a low speed, and promotes cooling and liquefaction in the condenser 4. . Cooling air from the condenser fan 6 is also used for cooling the fuel cell main body 3. Here, the structure is such that ventilation in the fuel cell main body 3 by the capacitor fan 6 can also be performed.

  The liquid water separated by the gas-liquid separator 5 is sent to the fuel cell main body 3 by the pump 10 and used for supplying water to the electrolyte membrane. Further, the outlet gas from the fuel cell main body 3 is supplied to the capacitor 4 via a connecting pipe. In the condenser 4, the outlet gas is cooled to liquefy the contained water vapor. Further, as described above, the shutter (air volume adjusting mechanism) 9 that closes the upper surface of the capacitor 4 is provided. There is a case where it is desired to warm up the capacitor 4 and the fuel cell main body 3 without cooling them at an extremely low temperature. In such a case, the shutter 9 is closed so that the condenser 4 and the fuel cell body 3 are not cooled more than necessary. The opening degree of the shutter 9 can be adjusted, and the cooling degree in the condenser 4 can be variably controlled.

  A view of the fuel cell system as viewed from the front of the vehicle is shown in FIG. FIG. 2 also shows the position of the radiator fan 12 provided along with the radiator that circulates the coolant in the fuel cell main body 3. As shown in FIG. 2, a total of two gas-liquid separators 5 are provided, one on each side of the radiator. Each gas-liquid separator 5 is designed not to overlap the radiator fan 12 when viewed from the front, and is considered not to lower the cooling efficiency of a radiator (not shown) provided in front of the radiator fan 12. ing. Further, since the cooling air discharged from the radiator fan 12 also cools the fuel cell main body 3 as it is, the gas-liquid separator 5 and the radiator fan 12 are not overlapped with each other in the front view. This also prevents the cooling efficiency of the battery body 3 from being lowered.

  Further, as described above, each gas-liquid separator 5 is connected to the capacitor 4 by the introduction portion 11, and these introduction portions 11 have a tapered shape and the outer periphery of the radiator fan 12. It is arranged in the part. For this reason, each introduction part 11 and the radiator fan 12 do not overlap with each other when viewed from the front, and it is considered here that the cooling efficiency of the fuel cell main body 3 by the radiator fan 12 is not lowered. Moreover, since the gas-liquid discharged | emitted from the capacitor | condenser 4 flows into the gas-liquid separator 5 via the introducing | transducing part 11 by gravity, a pump becomes unnecessary.

  FIG. 3 shows another installation example of the gas-liquid separator 5 and the radiator fan 12. In this example, only one gas-liquid separator 5 is installed, and two radiator fans 12 are installed. The radiator fans 12 are arranged side by side, and the gas-liquid separator 5 is disposed at the center thereof. The capacitor 4 and the gas-liquid separator 5 are connected by a pair of tapered introduction portions 11. Also here, the gas-liquid separator 5 does not overlap with the pair of radiator fans 12 when viewed from the front, and does not lower the cooling efficiency of the radiator (not shown) provided in front of the radiator fans 12. So that it is considered. Further, as in the case of FIG. 2, when the gas-liquid separator 5 and the radiator fan 12 are not overlapped in front view, the cooling efficiency of the fuel cell body 3 by the radiator fan 12 is not lowered. Yes.

  Further, the gas-liquid separator 5 is connected to the capacitor 4 by a pair of introduction portions 11, and these introduction portions 11 have a tapered shape and are arranged on the outer peripheral portion of the radiator fan 12. Has been. For this reason, each introduction part 11 and the radiator fan 12 do not overlap with each other when viewed from the front, and it is considered here that the cooling efficiency of the fuel cell main body 3 by the radiator fan 12 is not lowered. Moreover, since the gas-liquid discharged | emitted from the capacitor | condenser 4 flows into the gas-liquid separator 5 via the introducing | transducing part 11 by gravity, a pump becomes unnecessary.

  FIG. 4 shows a system layout configuration diagram of the second embodiment of the present invention. In the present embodiment, the same or equivalent components as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the present embodiment, instead of the shutter (air volume adjusting mechanism) 9 described above, a tilt angle variable mechanism that variably controls the tilt angle of the condenser 4 is provided so that the degree of cooling by the condenser 4 can be adjusted by a small series. It is. By increasing the angle α in FIG. 4 and bringing the condenser 4 closer to the cooling air introduction hole 8 so as not to generate a gap, most of the cooling air introduced from the cooling air introduction hole 8 is used for cooling. Can improve the cooling efficiency. Conversely, by reducing the angle α and increasing the gap between the condenser 4 and the cooling air introduction hole 8 (formed on the rear side of the condenser 4), the cooling air introduced from the cooling air introduction hole 8 can be reduced. A part is not used for cooling, but comes back, and cooling efficiency falls.

  By using this variable tilt angle mechanism, when it is desired to warm up the condenser 4 and the fuel cell body 3 without cooling them at extremely low temperatures, the angle α is increased so that the capacitor 4 and the fuel cell body 3 are more than necessary. Do not cool down. The angle α can be variably adjusted, and the degree of cooling in the condenser 4 can be variably controlled. The variable tilt angle mechanism of the present embodiment is constructed by forming the front end of the capacitor 4 as a hinge and disposing a cylinder 13 that can be expanded and contracted by hydraulic pressure at the rear end of the capacitor 4. Various pipes connected to the capacitor 4 are formed so as to be able to expand and contract or deform according to the change in the angle of the capacitor 4. This variable tilt angle mechanism and the air volume adjusting mechanism such as the shutter 9 described above can be used in combination. Further, the variable tilt angle mechanism and the condenser fan 6 can be used together. In both the first embodiment and the second embodiment, driving of the condenser fan 6 and the pump 10 angle adjustment function is controlled by a control unit (not shown).

  As described above, the fuel cell stack and the gas-liquid separator are disposed below the condenser in the vehicle front compartment. By doing in this way, the piping length of a fuel cell system can be made the shortest. Further, the lower part of the condenser can be connected to the upper part of the gas-liquid separator having a height, and there is no need to provide a pump or the like when introducing condensed water from the condenser to the gas-liquid separator. As a result, it is possible to realize a system that saves space and has high gas-liquid separation performance with the shortest pipes and the like.

  In addition, a capacitor fan is provided on the lower surface side of the capacitor, and the fuel cell stack is also cooled by the capacitor fan. In this way, the fuel cell main body can be ventilated, and ventilation can be performed without adding new parts. As a result, the layout can be improved and the weight of the system and the cost can be reduced by reducing the number of parts.

  In addition, a cooling fan for cooling the components in the front compartment of the vehicle is further provided, and the arrangement position of the gas-liquid separator is set so as not to overlap with the cooling fan when viewed from the vehicle front-rear direction. By doing in this way, a gas-liquid separator can be installed, without reducing the cooling efficiency by a cooling fan.

  Moreover, the introduction part for introducing the gas and liquid from the condenser to the gas-liquid separator was formed in a tapered shape on the outer peripheral part of the cooling fan described above. By doing so, it is possible to collect the condensed water from the condenser without affecting the cooling performance without being affected by the vehicle attitude or the vehicle acceleration.

  In addition, an air volume adjusting mechanism for adjusting the air volume passing through the capacitor is provided on the upper surface side of the capacitor. In this way, if you want to actively cool the condenser, increase the air volume to make the condenser easier to hit the cooling air and promote cooling, while reducing the air volume when you want to warm up the condenser The warm-up can be promoted without cooling as described above.

  Further, a tilt angle variable mechanism that variably controls the installation tilt angle of the capacitor as viewed from the side of the vehicle is further provided. In this way, when the condenser is actively cooled, it is adjusted to an angle at which the cooling air can easily hit the condenser to promote cooling. On the other hand, when the condenser is warmed up, the cooling air hits the condenser. The warm-up can be promoted by adjusting to a difficult angle so that cooling is not performed more than necessary.

  The fuel cell system of the present invention is not limited to the above-described embodiment. For example, instead of the shutter 9 in the above-described embodiment, a louver-like air volume adjusting mechanism whose opening degree can be adjusted may be provided below the cooling air introduction hole 8 (upper part of the condenser 4). In addition, the above-described variable tilt angle mechanism moves the back of the capacitor 4 up and down using a hydraulic cylinder, but as a mechanism that adjusts the tilt angle of the capacitor 4 using an electric actuator, pneumatic actuator, manual mechanism, or the like. Also good. Furthermore, in the above-described embodiment, the radiator fan 12 provided along with the radiator has been described as an example. However, the radiator fan 12 used for the description is for cooling other components in the vehicle front compartment 2. It may be a cooling fan. For example, a cooling fan installed to cool the fuel cell system (fuel cell main body 3) may be used.

It is a block diagram of 1st embodiment of the vehicle-mounted fuel cell system of this invention. It is a front view which shows the example of installation of a cooling fan. It is a front view which shows the other example of installation of a cooling fan. It is a block diagram of 2nd embodiment of the vehicle-mounted fuel cell system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Vehicle front compartment 3 Fuel cell main body 4 Capacitor 5 Gas-liquid separator 6 Capacitor fan 7 Bonnet hood 8 Cooling air introduction hole 9 Shutter (air volume adjustment mechanism)
10 Pump 11 Introduction 12 Radiator Fan 13 Cylinder (Inclination Angle Variable Mechanism)

Claims (7)

In the on-vehicle fuel cell system that cools the fuel cell outlet gas with a condenser, collects the liquid water condensed by the outlet gas cooling, and uses it for the operation of the fuel cell.
An in-vehicle fuel cell system, wherein the capacitor is disposed in an upper part of a vehicle front compartment.   The in-vehicle fuel cell system according to claim 1, wherein a fuel cell stack and a gas-liquid separator are disposed below the capacitor in the vehicle front compartment.   The in-vehicle fuel cell system according to claim 2, wherein a capacitor fan is provided on the lower surface side of the capacitor, and the fuel cell stack is also cooled by the capacitor fan. A cooling fan for cooling parts in the vehicle front compartment;
The in-vehicle fuel cell system according to claim 2 or 3, wherein an arrangement position of the gas-liquid separator is set so as not to overlap the cooling fan when viewed from the front-rear direction of the vehicle. A cooling fan for cooling parts in the vehicle front compartment;
The in-vehicle fuel according to any one of claims 2 to 4, wherein an introduction part for introducing gas-liquid from the capacitor to the gas-liquid separator is formed in a tapered shape on an outer peripheral part of the cooling fan. Battery system.   The in-vehicle fuel cell system according to any one of claims 1 to 5, wherein an air volume adjusting mechanism for adjusting an air volume passing through the capacitor is provided on an upper surface side of the capacitor.   The in-vehicle fuel cell system according to any one of claims 1 to 6, further comprising an inclination angle variable mechanism that variably controls an installation inclination angle of the capacitor as viewed from the side of the vehicle.

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