JP2012109151A - Fuel cell system and vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell system and a vehicle achieving high energy efficiency by utilizing the energy of high pressure in a hydrogen tank.SOLUTION: The fuel cell system comprises an expander 13 comprising a segment filled with hydrogen and a segment filled with a coolant 51 being an incompressible liquid, a compressor 23 comprising a pressurizing chamber 23g filled with air containing oxygen and a coolant chamber 23f filled with the coolant 51, and cooling piping 35a to 35i in which the coolant 51 is sealed up. The expansion of high pressure hydrogen introduced into the expander 13 introduces the coolant 51 into the coolant chamber 23f of the compressor 23 through the piping 35e to reduce the volume of the pressurizing chamber 23g; therefore, the air is compressed.

Description

  The present embodiment relates to a fuel cell system and a vehicle technology.

As in the fuel cell system described in Patent Document 1, in a conventional fuel cell vehicle or the like, fuel (hydrogen) to the fuel cell is filled and stored in a hydrogen tank in a high pressure state. When the high-pressure hydrogen is supplied to the fuel cell, the pressure is reduced to a predetermined pressure by a pressure reducing valve or the like and then supplied to the fuel cell.
On the other hand, the oxidant gas (air) is compressed and boosted by an air pump and then supplied to the fuel cell. Electric power generated by the fuel cell is used to drive the air pump.

  In Patent Document 2 and Patent Document 3, the turbine is rotated using the pressure energy of high-pressure hydrogen charged and stored in a hydrogen tank, and the turbine is directly connected to the turbine uniaxially using the rotational energy. A fuel cell system that compresses and pressurizes air by driving a centrifugal compressor is disclosed.

JP 2000-195533 A JP 2006-147246 A JP 2010-170729 A

As described above, in the conventional fuel cell system, the high pressure hydrogen in the hydrogen tank (high pressure fuel gas tank) is decompressed by the pressure reducing valve and then supplied to the fuel cell, so that the high pressure energy in the hydrogen tank is not used. The energy is not used as efficiently as possible.
Furthermore, as described above, since a part of the electric power generated by the fuel cell is used to drive the air pump, efficient use of energy is not realized.

  On the other hand, in the techniques described in Patent Document 2 and Patent Document 3, an efficient fuel cell system is realized by using high-pressure energy in the hydrogen tank for air compression / pressure increase.

  However, in the techniques described in Patent Document 2 and Patent Document 3, it is not considered to use a temperature decrease when high-pressure hydrogen expands in a turbine and a temperature increase when air is compressed / pressure-increased by a compressor. However, it cannot be said that the pressure energy in the hydrogen tank is fully utilized from the point of discarding these thermal energy. Further, in the techniques described in Patent Document 2 and Patent Document 3, when there is a difference between the hydrogen supply amount and the air supply amount, a means for adjusting the air supply flow rate is not taken into consideration. It is difficult to operate effectively under all power generation conditions of the system.

  Therefore, an object of the present invention is to provide a fuel cell system and a vehicle that can obtain high energy efficiency by utilizing high-pressure energy in a hydrogen tank.

  According to a first aspect of the present invention for solving the above problems, a high-pressure fuel gas tank that stores fuel gas, and a fuel that supplies the fuel gas discharged from the high-pressure fuel gas tank to a fuel cell stack are provided. A fuel cell system comprising a gas supply channel and an oxidant gas supply channel for supplying an oxidant gas to a stack, the fuel cell system being interposed in the fuel gas supply channel and supplying the fuel gas A fuel gas supply device including a gas supply unit and a liquid storage unit storing an incompressible liquid, and an oxidant gas supply unit that is disposed on the oxidant gas supply channel and supplies the oxidant gas An oxidant gas supply device comprising: a liquid introduction part into which the liquid is introduced; and a partition member that partitions them; and the fuel gas supply device and the oxidant gas supply device are connected, and the liquid is liquid-tight To be A connecting pipe, and a liquid is introduced into the liquid introducing portion of the oxidant gas supply device through the connection pipe by expansion of the fuel gas introduced into the fuel gas supply device, and the oxidant gas The oxidizing gas is compressed by reducing the volume of the supply unit.

  According to the first aspect of the present invention, since the oxidant gas (air) can be compressed and boosted with the energy generated during the decompression and expansion of hydrogen, an air pump having a dedicated motor can be dispensed with. In addition, in the oxidant supply device, heat generated when the oxidant gas is compressed and pressurized is transported to the fuel gas supply device through the liquid in addition to heat conduction between members constituting each cylinder. Can be used to warm up the fuel gas. Furthermore, by adjusting the position of the partition member, the volume of the oxidant gas cylinder in the oxidant supply device can be adjusted, and the oxidant can be supplied to the fuel gas supply amount necessary for power generation of the fuel cell system. Gas supply amount and pressure can be adjusted appropriately.

  The invention according to claim 2 is the fuel cell system according to claim 1, wherein the liquid is an antifreeze and incompressible refrigerant, and is used for cooling the fuel cell system. Features.

  According to the second aspect of the present invention, the refrigerant is circulated by the operation of the fuel gas supply device, so that the fuel gas supply device plays the role of the cooling water circulation pump, and a cooling water circulation pump can be separately installed. It becomes unnecessary.

  The invention according to claim 3 is the fuel cell system according to claim 1 or 2, wherein the fuel gas supply device includes a heat transfer promoting porous member that controls liquid flow and promotes heat transfer. It is stored.

  According to the third aspect of the invention, the behavior of the liquid level caused by the inclination of the vehicle can be suppressed, and the heat transfer promoting member accumulates the heat of the liquid and heats the fuel gas whose temperature is lowered when the fuel gas expands. Since it discharges, it can be brought close to isothermal expansion, and the utilization efficiency of pressure energy can be improved.

  The invention according to claim 4 is a vehicle equipped with the fuel cell system according to any one of claims 1 to 3.

  According to the invention concerning Claim 4, the vehicle carrying the fuel cell system as described in any one of Claims 1-3 can be provided.

  ADVANTAGE OF THE INVENTION According to this invention, the fuel cell system and vehicle which can acquire high energy efficiency can be provided by utilizing the high voltage | pressure energy in a hydrogen tank.

It is a figure which shows the structural example of the fuel cell system which concerns on this embodiment. It is a figure which shows the structural example of a honeycomb member. It is a figure which shows operation | movement of a fuel cell system (the 1). It is a figure which shows operation | movement of a fuel cell system (the 2).

  Next, modes for carrying out the present invention (referred to as “embodiments”) will be described in detail with reference to the drawings as appropriate. Although the fuel cell system according to the present embodiment is assumed to be mounted on a vehicle such as a fuel cell vehicle, it may be mounted on a ship, a motorcycle, a stationary power generator, or the like.

FIG. 1 is a diagram illustrating a configuration example of a fuel cell system according to the present embodiment.
The fuel cell system 1 includes a fuel cell 2, an anode gas supply system (anode system), a cathode gas supply system (cathode system), a cooling water circulation system (cooling system), and a humidification system.
(Fuel cell)
The fuel cell 2 is composed of, for example, a polymer electrolyte fuel cell (PEFC), and a MEA (Membrane Electrode Assembly) is sandwiched between conductive separators (not shown). A plurality of unit cells are stacked.

  The MEA includes an electrolyte membrane (solid polymer membrane), an anode and a cathode that sandwich the membrane. The anode and the cathode are each composed of an electrode catalyst layer in which a catalyst is supported on a catalyst carrier such as carbon. An anode flow path through which hydrogen (fuel gas) flows is formed in the separator facing the anode, and a cathode flow path through which air (oxidant gas) flows is formed in the separator facing the cathode. .

  In such a fuel cell 2, when hydrogen is supplied to the anode and oxygen-containing air is supplied to the cathode, an electrode reaction occurs on the catalyst included in the anode and the cathode, and the fuel cell 2 can generate power. Become.

  The fuel cell 2 is electrically connected to an external load (not shown), and the fuel cell 2 generates power when current is taken out by the external load. The external load is a traveling motor, a power storage device such as a battery or a capacitor, and the like.

(Anode system)
The anode system includes a hydrogen tank 11 as a high-pressure fuel gas tank, a high-pressure injection device 12, an expander 13 as a fuel gas supply device, a discharge hydrogen tank 14, an ejector compressor 15, pipes 16a to 16f, backflow prevention valves 17b to 17c, An electromagnetic valve 18 and a relief valve 19 are provided. In FIG. 1, the anode piping 16 a to 16 f are indicated by thick solid lines.

The hydrogen tank 11 stores hydrogen compressed at a high pressure, and is connected to the high-pressure injection device 12 through a pipe 16a. The hydrogen tank 11 has a built-in solenoid valve (not shown). When the ignition switch of the vehicle is turned on, the solenoid valve is also turned on and opened.
A secondary shut-off valve, a filter, and the like are provided between the hydrogen tank 11 and the high-pressure injection device 12, but illustration and description thereof are omitted here. Further, the pipe 16a, the high-pressure injection device 12, and the pipes 16b and 16c serve as fuel gas supply channels.
Here, the fuel cell system 1 according to the present embodiment does not include a pressure reducing valve between the hydrogen tank 11 and the high-pressure injection device 12, and the high-pressure hydrogen in the hydrogen tank 11 remains in a high-pressure state. It is supplied to the high pressure injection device 12.
In the pipe 16a, a relief valve 19 is installed between the hydrogen tank 11 and the high pressure injection device 12. The opening / closing control of the electromagnetic valve 18 is performed by an ECU (Engine Control Unit) not shown.

  The high-pressure injection device 12 holds hydrogen at a relatively high pressure. The high-pressure hydrogen in the high-pressure injection device 12 is supplied to the expander 13 through the fuel supply passage (pipe 16b). The high-pressure injection device 12 incorporates a valve (not shown) that is controlled by an ECU (Engine Control Unit) or the like, and the high-pressure hydrogen supply to the expander 13 is controlled by opening and closing the valve. Hereinafter, the valve built in the high pressure injection device 12 is referred to as a high pressure injection device built-in valve.

The expander 13 stores a honeycomb member (heat transfer promoting porous member) 13a having a honeycomb structure through which hollow holes 13z having a plurality of hexagonal cross sections pass inside a cylindrical metallic container as shown in FIG. The refrigerant 51, which is an incompressible liquid, is stored. The refrigerant 51 reciprocates up and down in the hollow hole 13z. In addition, heat exchange is performed between hydrogen and the refrigerant 51 using the wall surface through the hollow hole 13z of the honeycomb member 13a. In the present embodiment, the honeycomb structure has a structure in which hexagonal hollow holes (porous) 13z penetrate, but other polygons such as a triangle or a quadrangle may be used. The refrigerant 51 is preferably an antifreeze liquid. The honeycomb member 13a is preferably a member having a large heat capacity and high thermal conductivity. By doing in this way, the heat exchange between hydrogen and the refrigerant | coolant 51 can further be accelerated | stimulated.
The operation of the expander 13 will be described in detail later.
The hydrogen discharged from the expander 13 is sent to the fuel cell 2 through the pipe 16c. In addition, the solenoid valve 18 is installed in the piping 16c, and the supply / interruption of the discharged hydrogen from the expander 13 is controlled.
Here, in the present embodiment, it is assumed that the expander 13 and the honeycomb member 13a have a cylindrical shape, but the present invention is not limited to this, and a rectangular parallelepiped shape may also be used.

The discharged hydrogen tank 14 temporarily stores the unreacted hydrogen discharged from the fuel cell 2 and supplies it to the ejector compressor 15.
The ejector compressor 15 returns unreacted hydrogen to the fuel cell 2 by returning it to the pipe 16c.
A refrigerant 51 is stored in the ejector compressor 15, and a partition member 15 b is liquid-tightly arranged on the liquid level of the refrigerant 51 so as to be movable up and down in the cylinder of the ejector compressor 15. The partition member 15b is connected to the upper surface of the cylinder of the ejector compressor 15 via a spring 15a.
Here, in the present embodiment, the ejector compressor 15 is assumed to have a cylindrical shape, but is not limited thereto, and may be a rectangular parallelepiped shape.
The operation of the ejector compressor 15 will also be described in detail later.

(Cathode system)
The cathode system includes an intake 21, a filter 22, a compressor 23 as an oxidant gas supply device, pipes 24a to 24c as oxidant gas supply passages, backflow prevention valves 25a and 25b, and the like. In FIG. 1, the cathode piping 24a to 24c are indicated by thin solid lines.
The intake 21 takes in air containing oxygen from the outside air. The filter 22 removes foreign matters mixed in the taken-in air.

The compressor 23 includes a cylinder 23a, a piston 23b, a spring 23c, partition members 23d and 23e, and the like. The partition member 23d is fitted in the lower part of the piston 23b, and forms a refrigerant chamber (liquid introducing part) 23f sealed in the lower part of the compressor 23. The refrigerant chamber 23 f is filled with the refrigerant 51. The partition member 23e is fitted to the upper part of the piston 23b, and forms a boosting chamber (oxidant gas supply unit) 23g in the upper part of the compressor 23. The piston 23b and the partition members 23d and 23e correspond to the partition member in the claims.
The upper part of the piston 23b is connected to the upper surface in the cylinder of the compressor 23 via a spring 23c.
Although the operation of the compressor 23 will be described in detail later, air is supplied to the compressor 23 via the pipe 24b, and the air discharged from the compressor 23 is sent to the fuel cell 2 via the pipe 24c, and is in the air. After the oxygen reacts with hydrogen in the fuel cell 2, the air containing unreacted oxygen is discharged to the outside air through the ventilation device 61.
In the drawings in the present embodiment, the compressor 23 is shown upside down in order to avoid complication. In the present embodiment, a plurality of compressors 23 are used.
Here, in the present embodiment, it is assumed that the compressor 23 has a cylindrical shape. However, the compressor 23 is not limited to this and may have a rectangular parallelepiped shape.

(Cooling system)
The cooling system cools the fuel cell system 1 and includes a thermostat valve 31, an ion exchanger 32, a radiator 33, pipes 35a to 35i, backflow prevention valves 36a and 36b, and the like. In FIG. 1, the cooling system pipes 35a to 35i are indicated by thick broken lines. Of the pipes 35a to 35i, the pipe 35e corresponds to a connection pipe in the claims.
The thermostat valve 31 switches the flow path when, for example, the volume of wax inside changes with temperature.
The ion exchanger 32 collects ions present in the refrigerant with an ion exchange resin filled in the container in order to suppress an increase in conductivity in the refrigerant 51.
The radiator 33 cools the refrigerant 51 circulating through the cooling system by a radiator fan (not shown). The refrigerant 51 is a liquid and is preferably an incompressible antifreeze as described above.

A refrigerant 51 circulates in the pipes 35a to 35i. The refrigerant 51 circulates in the order of the ion exchanger 32 or the radiator 33 → the expander 13 → the compressor 23 → the ejector compressor 15 → the fuel cell 2 → the ion exchanger 32 or the radiator 33.
As will be described later, the expander 13 plays the role of a water pump that circulates the refrigerant 51. Therefore, the fuel cell system 1 according to this embodiment does not include a water pump having a dedicated motor.

(Humidification system)
The humidification system humidifies the air supplied to the fuel cell 2, and includes a gas-liquid separator 41, a humidification pump 42, and the like. In FIG. 1, the humidification system pipe is indicated by a thin broken line.
The gas-liquid separator 1 has, for example, a box shape, and when a predetermined amount of generated water (water generated by the reaction in the fuel cell 2) accumulates, the generated water is discharged to the outside. A part of the water discharged from the gas-liquid separator 41 is supplied to the humidification pump 42, and the rest is discharged to the outside through the ventilator 61.
The humidification pump 42 is a pump that supplies the generated water supplied from the gas-liquid separator 41 to the pressure increasing chamber 23g of the compressor 23. The generated water supplied to the compressor 23 is sprayed into the compressor 23 by an injector described later. Then, the air generated by the compression of the air in the compressor 23 is vaporized to humidify the air supplied to the fuel cell 2. In FIG. 1, the generated water is separated and recovered only from the anode exhaust gas, but the generated water is separated from and recovered from only the cathode exhaust gas, and the generated water is discharged from both the anode and cathode exhaust gases. The form which isolate | separates and collect | recovers may be sufficient.

(Detailed description of operation)
Next, operations of the expander 13, the compressor 23, and the ejector compressor 15 in the fuel cell system according to the present embodiment will be described in detail with reference to FIGS. 3 and 4, the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. 3 and 4, the honeycomb member 13a stored in the expander 13 is omitted, and the compressor 23 is abbreviated as one.
As shown in FIGS. 3 and 4, the expander 13 has an intake port 13b and an exhaust port 13c, the ejector compressor 15 has an exhaust port 15c and an intake port 15d, and the compressor 23 has an intake port 23h and an exhaust port. It has a mouth 23i. Further, the compressor 23 has an injector 23j for spraying the generated water sent from the humidification pump 42 into the compressor 23.

A pipe 16 b from the high pressure injection device 12 is connected to the intake port 13 b of the expander 13, and a pipe 16 c is connected to the exhaust port 13 c of the expander 13.
The piping 16 f is connected to the exhaust port 13 b of the ejector compressor 15, and the piping 16 e is connected to the intake port 15 d of the ejector compressor 15.
A pipe 24b from the filter 22 (FIG. 1) is connected to an intake port 23h of the compressor 23, and a pipe 24c is connected to an exhaust port 23i of the compressor 23.

First, when the solenoid valve 18 (FIG. 1) is closed (indicated by a cross in the piping 16c), a high pressure injection valve (not shown) is opened, and as shown in FIG. 3, the inlet 13b of the expander 13 is opened. When high pressure hydrogen is supplied from the high pressure injection device 12, the hydrogen expands in the expander 13.
As a result, the refrigerant 51 in the expander 13 is pushed down. The pushed down refrigerant 51 flows into the refrigerant chamber 23f of the compressor 23 and the refrigerant chamber below the partition member 15b of the ejector compressor 15 through the liquid-tight pipe 35e. At this time, in the expander 13, the part filled with hydrogen is the fuel gas expansion part, and the part filled with the refrigerant 51 is the liquid storage part.

At this time, the high-pressure hydrogen in the cylinder of the expander 13 causes a temperature drop due to adiabatic expansion. The refrigerant 51 exchanges heat through the wall surface of the honeycomb member 13a (FIG. 1). As a result, the hydrogen is heated and the refrigerant 51 is cooled. By utilizing the temperature drop due to the expansion of the high-pressure hydrogen, the refrigerant 51 can be cooled, and the amount of heat exchange in the radiator 33 can be reduced, so that the radiator 33 can be made smaller or unnecessary. Further, the heat generated in the fuel cell 2 can be used for warming (humidification) of hydrogen.
Furthermore, since the heat generated in the fuel cell 2 can be further expanded by exchanging heat between the refrigerant 51 and the hydrogen, the energy efficiency of the entire fuel cell system 1 can be further improved. .

  The refrigerant 51 flowing into the refrigerant chamber 23f pushes up the piston 23b of the compressor 23. Thereby, the air in the pressure increasing chamber 23g of the compressor 23 is compressed. At this time, generated water is sprayed into the pressure increasing chamber 23g from the injector 23j controlled by the ECU. The sprayed product water is vaporized by utilizing the temperature rise of the compressed air, and humidifies the air in the pressurizing chamber 23g.

  The compressed and pressurized air is exhausted from the exhaust port 23i and supplied to the fuel cell 2 via the pipe 24c (FIG. 1). At this time, air does not flow from the suction port 23h of the compressor 23 in the compression stroke by the backflow prevention valve 25a (FIG. 1) provided on the suction side of the compressor 23.

  Further, the refrigerant flowing out of the expander 13 flows into the refrigerant chamber below the partition member 15b in the ejector compressor 15 via the refrigerant chamber 23f of the compressor 23 and the pipes 35f to 35h (FIG. 1), and the ejector compressor 15 The liquid level (partition member 15b) is pushed up. As a result, unreacted hydrogen that has flowed into the ejector compressor 15 is discharged from the exhaust port 15 c to the pipes 16 f and 16 c (FIG. 1) and supplied to the fuel cell 2. Note that the backflow prevention valve 17b (FIG. 1) provided on the suction side of the ejector compressor 15 does not allow the discharged hydrogen to flow back from the suction port 15d to the fuel cell 2 (indicated by a cross in the pipe 16e). ).

  A predetermined amount of high-pressure hydrogen is introduced into the expander 13 from the high-pressure injector built-in valve, and then the high-pressure injector built-in valve is closed. Then, after a predetermined time controlled by the ECU (the liquid level of the refrigerant 51 in the expander 13 is sufficiently lowered), the electromagnetic valve 18 (FIG. 1) provided in the pipe 16c is opened. Thereby, hydrogen in the expander 13 is discharged, and the pressure of hydrogen on the liquid surface in the expander 13 is weakened. Then, since the pressure of the refrigerant 51 stored in the ejector compressor 15 and the compressor 23 is also weakened, the piston 23b is pushed down by the spring 23c provided in the compressor 13 as shown in FIG. Further, the coolant level (partition member 15b) is pushed down by a spring 15a provided in the ejector compressor 15. By pushing down the piston 23b and the partition member 15b, the refrigerant 51 stored in the refrigerant chamber 23f of the compressor 23 and the ejector compressor 15 is pushed out. At this time, air sucked from outside air flows from the suction port 23h of the compressor 23, and unreacted hydrogen from the discharged hydrogen tank 14 (FIG. 1) flows from the suction port 15d of the ejector compressor 15.

The refrigerant 51 pushed out from the ejector compressor 15 is supplied to the fuel cell 2 to cool the fuel cell 2 and then supplied to the compressor 23 via the thermostat valve 31 → the ion exchanger 32 or the radiator 33 (FIG. 1). Is done.
The refrigerant 51 pushed out from the compressor 23 is supplied to the expander 13 through a pipe 35e and the like. As described above, since the high-pressure injection device built-in valve (not shown) is closed, the pressure on the liquid surface in the expander 13 is weakened and further pressed by the springs 23c and 15c. The refrigerant 51 cannot newly flow into the compressor 15. Accordingly, the refrigerant 51 supplied to the expander 13 is stored in the expander 13. Thereby, the liquid level of the refrigerant | coolant 51 in the expander 13 rises, and the hydrogen in the expander 13 is discharged | emitted from the discharge port 13c.
In the stage of FIG. 4, hydrogen does not flow back from the discharge port 15c of the ejector compressor 15 by the backflow prevention valve 17c (FIG. 1) (indicated by a cross in the pipe 16f), and the backflow prevention valve 25a (FIG. 1), air does not flow backward to the suction port 23h of the compressor 23 (indicated by a cross in the pipe 24b).

Then, when the solenoid valve 18 (FIG. 1) is closed again in response to an instruction from the ECU and a high-pressure injection device built-in valve (not shown) is opened again, the discharge of hydrogen stops and the flow of hydrogen into the expander 13 resumes. Returning to the state of FIG.
Hereinafter, the fuel cell system 1 repeats the steps of FIGS. 3 and 4.

(Summary)
With such a configuration, air can be compressed using the pressure energy at the time of hydrogen expansion in the expander 13, so that an air pump having a dedicated motor for supplying air to the fuel cell 2 is not required, and the fuel The energy efficiency of the entire battery system 1 can be improved.
Furthermore, by adjusting the length of the piston 23b of the compressor 23, the size of the partition member 23e, the length of the spring 23c, and the spring constant, the size of the boosting chamber 23g in the compressor 23 can be changed, Even when there is a difference between the supply amount and the air supply amount, the air supply amount can be adjusted to an appropriate amount by a simple operation.

Further, since the refrigerant 51 is stored in the expander 13 and the refrigerant 51 is circulated using the pressure energy of hydrogen expansion, a water pump having a dedicated motor for circulating the refrigerant 51 can be eliminated. .
And by using liquids, such as the refrigerant | coolant 51, as an energy transmission means, the external leak of hydrogen can be prevented and lubricating oil etc. can be made unnecessary.

Further, by storing the honeycomb member 13 a in the expander 13, the behavior of the liquid level of the refrigerant 51 is controlled, and the contact area with the refrigerant 51 is increased, so that heat transport to the refrigerant can be promoted. . Thereby, the heat exchange function in the expander 13 can be promoted. Further, by storing the honeycomb member 13 a in the expander 13, it is possible to suppress liquid level movement when the vehicle is inclined.
Alternatively, the heat generated in the fuel cell 2 can be further expanded by exchanging heat between the refrigerant 51 and the hydrogen, so that the energy efficiency of the entire fuel cell system 1 can be further improved. it can.

(Modification)
In the present embodiment, one expander 13 is provided. However, the present invention is not limited to this, and a plurality of expanders 13 may be provided, or the expanders 13 may be connected so as to correspond to the compressor 23. Alternatively, in the present embodiment, as shown in FIG. 1, the refrigerant 51 is sequentially supplied to the plurality of compressors 23, but the pipes branched from the pipes 35 e are connected to the respective compressors 23. The refrigerant 51 may be supplied to each compressor 23 at the same time.
Note that when only one expander 13 is provided, the high-pressure injection device 12 has a function as a flow rate adjusting means. In this case, the high-pressure injection device 12 can be replaced with other flow rate adjusting means such as a valve.
Further, the partition member 15b can be omitted.

  A valve may be provided in each of the expander 13 and the suction port and the exhaust port of the compressor 23. By doing in this way, supply pressure of hydrogen and air can be controlled. Moreover, unnecessary expander 13 and compressor 23 can be stopped by adjusting the opening and closing of the valve.

  The compressor 23 may be a diaphragm pump, for example.

1 Fuel cell system 2 Fuel cell (stack)
11 Hydrogen tank (high pressure fuel gas tank)
12 High-pressure injection device (fuel gas supply flow path)
13 Expander (Fuel gas supply device: Including fuel gas introduction part and liquid storage part)
13a Honeycomb member (heat transfer promoting porous member)
14 Exhaust hydrogen tank 16a to 16f Anode system piping (including fuel gas supply flow path)
17b to 17c Anode backflow prevention valve 18 Solenoid valve 19 Relief valve 21 Intake 22 Filter 23 Compressor (oxidant supply device)
23a Cylinder 23b Piston (partition member)
23c Spring 23d, 23e Partition member 23f Refrigerant chamber (liquid introduction part)
23g Pressure chamber (oxidant gas supply part)
23j Injectors 24a-24c Cathode system piping (oxidant gas supply flow path)
25a, 25b Cathode system backflow prevention valve 31 Thermostat valve 32 Ion exchanger 33 Radiator 35a-35i Cooling system piping (including connection piping)
36a, 36b Cooling system check valve 41 Gas-liquid separator 42 Humidification pump 51 Refrigerant

Claims (4)

A high-pressure fuel gas tank that stores fuel gas, a fuel gas supply channel that supplies the fuel gas discharged from the high-pressure fuel gas tank to a stack of a fuel cell, and an oxidant gas supply that supplies oxidant gas to the stack A flow path;
A fuel cell system comprising:
A fuel gas supply device that is interposed in the fuel gas supply flow path and includes a fuel gas supply unit that supplies the fuel gas, and a liquid storage unit that stores an incompressible liquid;
An oxidant gas supply that is disposed on the oxidant gas supply flow path and includes an oxidant gas supply part that supplies the oxidant gas, a liquid introduction part that introduces the liquid, and a partition member that partitions them. Equipment,
A connecting pipe that connects the fuel gas supply device and the oxidant gas supply device and is liquid-tight with the liquid;
Further comprising
Liquid is introduced into the liquid introduction part of the oxidant gas supply device through the connection pipe by expansion of the fuel gas introduced into the fuel gas supply device, and the volume of the oxidant gas supply part is reduced. The fuel cell system, wherein the oxidant gas is compressed in The liquid is an antifreeze and incompressible refrigerant,
The fuel cell system according to claim 1, wherein the fuel cell system is used for cooling the fuel cell system. 3. The fuel cell system according to claim 1, wherein the fuel gas supply device stores a heat transfer promoting porous member that controls liquid flow and promotes heat transfer. 4.   A vehicle equipped with the fuel cell system according to any one of claims 1 to 3.

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