JP2001085040A - Fuel cell power supply system and its operating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell power supply system and its operating method capable of shortening the start time and securing a long time operation even if the fuel supply is small. SOLUTION: The fuel cell power supply system and its operating method is composed of a fuel cell body 7, a hydrogen manufacturing device 2 to reform a fuel by a reformer 2a and supply it to the cell body 7, a hydrogen storage alloy tank 3 to store hydrogen gas, an air supply device 6 including a blower 6b interlocking with a turbine 6a for supplying air to the cell body 7, and a burner 5 for the air supply device to rotate the turbine 6a and heat the tank 3 using the exhaust gas. From the tank 3 and air supply device 6, hydrogen and air are supplied to the cell body 7 to start the power generation, and reformation of the crude fuel by the reformer 2a is started, and after attainment of the stage at which the reformer 2a can supply a hydrogen-rich gas to allow the fuel cell body 7 to generate power, the hydrogen source in the cell body 7 is changed over to the hydrogen producing device 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell power supply system which is used, for example, as a portable power supply, a power supply for an electric vehicle, a household power supply, a power supply for a building, etc., and has improved startup time and operation time. It relates to the driving method.

[0002]

2. Description of the Related Art In a fuel cell, an electrolyte membrane is interposed between a fuel electrode (anode) and an oxidant electrode (cathode) which are arranged oppositely to supply fuel to an anode and oxidant to a cathode. This is a device that generates electric power.
Since such a fuel cell is not restricted by the Carnot cycle as in the existing thermal power generation system, high power generation efficiency can be expected. If waste heat is used, more efficient energy use can be achieved. In addition, the fuel cell is low in noise and clean in exhaust gas, and thus is excellent in environmental harmony.

Among such fuel cells, in the case of a polymer electrolyte fuel cell using a solid polymer as an electrolyte membrane, since a liquid electrolyte is not used, it is hard to corrode, and other types of fuel cells, For example, since a much higher current density can be obtained as compared with a phosphoric acid fuel cell, a molten carbonate fuel cell, or the like, there is an advantage that a high output density can be obtained.
Therefore, polymer electrolyte fuel cells have been developed as portable power supplies, electric vehicle power supplies, home power supplies, building power supplies, and the like. In particular, a power supply system using a polymer electrolyte fuel cell can supply a specific fuel, such as gasoline in a gasoline-powered vehicle, instead of charging from the outside, because high power density can be expected as described above. It is expected to be used as a power source for electric vehicles that can travel.

As a power supply system for such an electric vehicle, for example, a combination of a polymer electrolyte fuel cell and a hydrogen tank or a hydrogen storage alloy tank for supplying hydrogen as a gaseous fuel has been developed. However, the lack of a supply infrastructure for hydrogen, which is a fuel, and the distance that can be traveled in a single hydrogen charge are at most 200.
The short distance of not more than km prevents the spread of electric vehicles using such a power supply system. For example, 200k
g of hydrogen storage alloy can store at most 4kg
About 45 Nm 3 of hydrogen,
The capacity is about Wh. Although it is possible to drive for about 3 hours at 20 kW, it is estimated at a maximum that the running distance is at most 180 km even if the vehicle runs at 60 km / h.

Accordingly, an electric vehicle has been proposed in which a polymer electrolyte fuel cell is combined with a reformer for a liquid fuel such as methanol to run by supplying methanol as a liquid fuel in the same manner as gasoline in a gasoline vehicle. ing. According to such an electric vehicle, there is an advantage that not only a traveling distance on the order of 500 km, comparable to that of a gasoline-powered vehicle, can be achieved, but also the infrastructure for supplying methanol can be dealt with by a small modification of a gas station.

[0006] However, the reformer for liquid fuel such as methanol used in such a power supply system has a problem that it takes 10 minutes or more to start. Japanese Patent Application Laid-Open No. 9-266006 describes a power supply system for coping with this.
The invention disclosed in the official gazette will be described below with reference to FIGS. FIG. 7 shows an example using a hydrogen tank, and FIG. 8 shows an example using a high-pressure storage alloy tank.

That is, the power supply system shown in FIG. 7 includes a polymer electrolyte fuel cell main body 31, a reforming volume variable reformer 32, a hydrogen purification compressor 33, and a high-pressure hydrogen tank. The variable reforming volume reformer 32 is a reformer equipped with a reforming catalyst and having a variable capacity of a reforming section for reforming raw fuel into a reformed gas containing hydrogen as a main component. In other words, in the reforming volume variable reformer 32, the heating chamber heated by the burner is divided into a plurality of sections, and the reformable area can be changed depending on which of the heating chambers burns. .

The fuel cell body 31 has a solid polymer electrolyte membrane interposed between a fuel electrode and an oxidizing agent electrode, and a reformed gas supplied from a variable reforming volume reformer 32 and an oxidizing agent. Is a fuel cell that generates power by an electrochemical reaction with The hydrogen purifying compressor 33 is a compressor having a hydrogen purifying unit for converting lean hydrogen remaining in the fuel cell main body 31 to pure hydrogen and a hydrogen compressing unit for converting pure hydrogen to high-pressure hydrogen. The high-pressure hydrogen tank 34 is a hydrogen storage / supply device that stores high-pressure hydrogen from the hydrogen purification compressor 33 and supplies hydrogen to the fuel cell main body 31.

The power supply system shown in FIG. 8 is provided with a high-pressure storage alloy tank 50 having a high volume density in place of the high-pressure hydrogen tank 34 described above. The high-pressure storage alloy tank 50 is a tank using a hydrogen storage alloy having a property of releasing hydrogen by heating and depressurization and absorbing hydrogen by cooling and pressurization, and includes a hot water tank 51 having heating and cooling functions. It is connected to a cold water tank 52. In addition, a hydrogen source pipe 35 is connected to the high-pressure hydrogen tank 34 and the high-pressure storage alloy tank 50, and other devices are appropriately connected by pipes 36 to 42.

The operation method of such a fuel cell power supply system is as follows. That is, at the time of startup, hydrogen from the high-pressure hydrogen tank 34 or the high-pressure storage alloy tank 50 is supplied to the fuel cell main body 31 via the pipe 36 to generate power.

Then, the hydrogen (anode exhaust gas) remaining in the fuel cell main body 31 is passed through a pipe 37, a hydrogen purification compressor 33 and a pipe 38 to a reforming section of the variable reformer 32. The mixture is supplied to some of the burners and burned to partially heat the plurality of heating chambers and raise the temperature to a temperature at which reforming is possible. As described above, the reformed gas generated by supplying the raw fuel to the reformable portion that can be reformed by heating is supplied to the fuel cell main body 31 through the pipe 40. Further, the hydrogen, the reformed gas, and the oxidant remaining in the fuel cell main body 31 are supplied to the burners of the reforming sections other than the reformable section in the reforming volume variable reformer 32, and are burned. Then, the reformable portion in the reforming section is sequentially increased, and the reformable section is expanded.

Further, when the external load is reduced, the capacity of the reformable portion in the variable reformer 32 is reduced, and the reforming capacity is reduced. Then, even after the external load disappeared, power was supplied to the hydrogen purification compressor 33 to generate high-pressure hydrogen, and this high-pressure hydrogen was supplied until the high-pressure hydrogen tank 34 or the high-pressure storage alloy tank 50 reached a predetermined pressure. After that, the operation is stopped.

[0013]

By the way, in the conventional fuel cell power generator as described above, at the time of starting, the power generation in the polymer electrolyte fuel cell is performed by the hydrogen gas from the high-pressure hydrogen tank or the high-pressure storage alloy tank. In addition, by adopting a reformer in which the volume of the reformable section in the reforming section is variable, it is possible to shorten the time required to reach the reformable state.

However, the variable reforming volume reformer has a complicated structure in which the reforming section is separated into a plurality of heating chambers, these heating chambers are partially heated, and the raw fuel is supplied only to the heating sections. And the reliability in the long term is not always sufficient. In addition, at the time of startup, since the anode exhaust gas from the fuel cell body is used as a heating source of the variable reformer, the problem is that a considerable amount of hydrogen is consumed.

The present invention has been developed to solve the problems of the prior art as described above.
It is an object of the present invention to provide a fuel cell power supply system capable of shortening a start-up time without using complicated equipment and securing a long operation time even with a small amount of fuel supply, and an operation method thereof.

[0016]

In order to achieve the above object, according to the first aspect of the present invention, a fuel cell main body and a raw fuel are converted into hydrogen-rich gas by a reformer and supplied to the fuel cell main body. A hydrogen production means, a hydrogen storage means for storing hydrogen gas supplied to the fuel cell body, and an air supply means for supplying air to the fuel cell body, wherein the hydrogen storage means A hydrogen storage alloy tank having a hydrogen storage alloy capable of attaching and detaching hydrogen in accordance with a temperature, wherein a combustion burner for heating the hydrogen storage alloy tank directly or by exhaust gas is provided. According to a tenth aspect of the present invention, in the operating method of the fuel cell power supply system, the hydrogen storage alloy tank is heated by using a combustion burner to supply hydrogen to the fuel cell main body, and the fuel cell is supplied from the air supply means. Power generation is started by supplying air to the main body, and in the hydrogen production means equipped with a reformer, reforming of raw fuel is started, and the reformer generates a hydrogen-rich gas capable of generating power in the fuel cell main body. After reaching the supply stage, the hydrogen supply source of the fuel cell main body is switched to the hydrogen production means. According to the first and tenth aspects of the present invention, at the time of startup, the combustion burner heats the hydrogen stored in the hydrogen storage alloy to a temperature at which the hydrogen stored in the hydrogen storage alloy is desorbed, and transfers the hydrogen from the hydrogen storage alloy tank to the fuel cell main body. , The fuel cell body can immediately enter a power generation state. After that, by switching the hydrogen supply source to the fuel cell main body from the hydrogen storage alloy tank to the hydrogen production device, long-term operation becomes possible. Further, if the hydrogen storage alloy tank is directly heated by the combustion burner, the heating of the hydrogen storage alloy can be accelerated and the time until the start of the supply of hydrogen to the fuel cell body can be shortened, so that the start-up time can be further reduced.

According to a second aspect of the present invention, in the fuel cell power supply system according to the first aspect, the air supply means includes a turbine rotating by exhaust gas from the combustion burner, and the fuel cell main body interlocked with the turbine. And a blower for sending air to the air blower. According to the second aspect of the present invention, since the means for operating the air supply means and the means for heating the hydrogen storage alloy tank are also used, the exhaust heat can be used efficiently.

According to a third aspect of the present invention, in the fuel cell power supply system according to the first or second aspect, the combustion burner is configured so that the reformer can be heated by the exhaust gas. Is connected to the terminal. In the third aspect of the present invention, since the means for heating the hydrogen storage alloy tank and the means for heating the reformer are also used, the exhaust heat can be used efficiently.

According to a fourth aspect of the present invention, in the fuel cell power supply system according to the first or second aspect, the fuel cell main body is provided with a cell cooling unit for cooling with cooling water, And a cooling water supply unit connected to the hydrogen storage alloy tank so that the tank can be cooled by the cooling water. According to the fourth aspect of the present invention, when hydrogen supplied from the hydrogen production device is stored in the hydrogen storage alloy, the hydrogen can be cooled to the storage temperature range using the cooling water of the fuel cell body. Become.

According to a fifth aspect of the present invention, in the fuel cell power supply system according to any one of the first to fourth aspects, heating means for heating cooling water is connected to the cooling section,
The combustion burner is connected to the heating means so that the exhaust gas serves as a heat source of the heating means. Further, the invention according to claim 6 is the invention according to claims 1 to 5
In the fuel cell power supply system according to any one of the above, a heating unit for heating cooling water is connected to the cooling unit, and the reformer is configured to directly supply heat required for the reforming to the reformer. A reformer burner is provided, and the reformer burner is connected to the heating means such that the exhaust gas serves as a heat source of the heating means. According to the fifth and sixth aspects of the present invention described above, it is possible to heat the cooling water to raise the operating temperature to the operating temperature or to keep the temperature higher than the freezing temperature at the time of startup or at the time of keeping the temperature in a cold region during a stop. it can. Further, since a combustion burner or a reformer burner is used as a heat source of the heating means, the exhaust heat can be efficiently used.

According to a seventh aspect of the present invention, in the fuel cell power supply system according to any one of the first to sixth aspects, the reformer is provided so as to be able to supply exhaust gas from the fuel cell body. It is characterized by being. According to the seventh aspect of the present invention, since the exhaust gas of the fuel cell body can be used as the heat source of the reformer, the amount of fuel used for the heat source of the reformer can be reduced, and the system efficiency can be improved. It becomes possible.

According to an eighth aspect of the present invention, in the fuel cell power supply system according to any one of the first to seventh aspects, the reformer directly supplies heat required for reforming to the reformer. A burner is provided, and the air supply means has a small capacity air supply blower for supplying air to the combustion burner, and a large capacity air supply blower for supplying air to the reformer burner and the fuel cell body. It is characterized by.
According to the eighth aspect of the invention, the use of two types of air supply blowers makes it possible to easily and appropriately adjust the amount of air supply.

According to a ninth aspect of the present invention, in the fuel cell power supply system according to any one of the first to eighth aspects, a battery is provided as a power supply for a device constituting the system at the time of startup. A switching device for switching to one of the battery and the fuel cell main body is provided. The invention according to claim 11 is
The operating method of the fuel cell power supply system according to claim 10, wherein at startup, a battery is used as a power supply of a device included in the system, and after the fuel cell body is in a power generation state by hydrogen from the hydrogen storage alloy tank, The power supply of the system is switched from the battery to the fuel cell main body. According to the ninth and eleventh aspects of the present invention, the power supply is switched from the battery to the fuel cell main body at the time when the fuel cell main body enters the power generation state by the hydrogen in the hydrogen storage alloy tank. Wear can be minimized.

According to a twelfth aspect of the present invention, in the operating method of the fuel cell power supply system according to the tenth or eleventh aspect, the hydrogen-rich gas from the reformer is stored before stopping the reformer. It is characterized in that it is supplied into an alloy tank. Further, the invention according to claim 13 is based on claim 1.
The method for operating a fuel cell power supply system according to any one of 0 to 12, wherein the reformer is operated excessively, and a hydrogen-rich gas generated by the excessive operation is supplied to the water storage alloy tank. And According to the above-described inventions of the twelfth and thirteenth aspects, the hydrogen storage amount in the hydrogen storage alloy tank can be set to be larger than the required amount for always starting, so that hydrogen gas deficiency occurs. It can be started at any time without having to.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to FIGS.

(1) First Embodiment 1-1. Configuration 1-1-1. Overall Configuration One embodiment of the present invention will be described in detail with reference to FIG. Note that m to r in FIG. 1 indicate that the portions denoted by the same reference numerals are connected. That is, in the present embodiment, the liquid fuel tank 1, the hydrogen production device 2, the hydrogen storage alloy tank 3, the hydrogen storage alloy temperature control device 4A, the combustion burner 5 for the air supply device, the air supply device 6, the solid polymer electrolyte Type fuel cell body 7, air supply blower 11A, liquid fuel supply pump 11B, battery cooling water circulation pump 12,
The battery cooling water cooling heat exchanger 14A and the battery cooling water heating heat exchanger 14B are connected by pipes, and each pipe is provided with a fluid flow control valve 15 to 25B.

The control device 9 for controlling the entire system is connected to the flow control valves 15 to 25B via a command signal line 27, and the load device 26,
It is connected to the starting device 10A and the power switching device 10B. Further, the fuel cell main body 7 is connected to a load device 26 such as an electric vehicle, a starting device 10A, and a power switching device 10B via a power wiring 29A. The air supply blower 11A, the liquid fuel supply pump 11B, and the battery cooling water circulation pump 12 are connected to the activation device 10A and the power supply switching device 10B via the electric wiring 30. Further, a battery (secondary battery) 8 is connected to the activation device 10A and the power supply switching device 10B via the power supply wiring 29B.
Is connected, the fuel cell body 7 is connected to the load device 2
6 can be driven and the battery 8 can be charged.

The battery 8 is a power supply for supplying power to the air supply blower 11A, the liquid fuel supply pump 11B, and the battery cooling water circulation pump 12 together with the fuel cell main body 7, and is used for igniting the combustion burner 5 for the air supply. It also has a function as a power supply. As the battery 8, lead-acid batteries, lithium batteries, nickel-metal hydride batteries, and other various types of secondary batteries conventionally used in automobiles can be used. As will be described later, the battery 8 is supplied with a starting air supply blower 11A and a liquid fuel supply pump 11 when the power supply system is started.
B, since it is necessary to work as a main power source for driving the combustion burner 5, the control device 9 and the power supply switching device 10B for the air supply device, it has a capacity with a predetermined margin based on expected operating conditions and the like. ing.

1-1-2. Configuration of Fuel Cell Main Body The fuel cell main body 7 has a stack structure in which a single cell is a constituent unit and a large number of the single cells are stacked. A single cell is
For example, a perfluorinated ionomer (trade name: Nafion
The smallest unit of the power generation element is a solid polymer ion conductive membrane such as a membrane of DuPont Corporation sandwiched between a fuel electrode (anode) 7a as a negative electrode and an oxidant electrode (cathode) 7b as a positive electrode. Say. Specifically, the stack structure is formed by stacking a large number of single cells via a separator having a supply path for supplying a hydrogen-containing gas to an anode and a supply path for supplying air containing an oxidizing gas. The cooling chamber 7c provided with a cooling water supply path for discharging heat generated by the power generation reaction to the outside is provided for each cell or every several cells.

The fuel cell body 7 receives the fuel gas containing hydrogen on the anode 7a side,
By receiving a supply of oxygen-containing oxidizing gas on the side, the following electrochemical reaction occurs, and an electromotive force is obtained.
Equation 1 indicates an anode electrode reaction on the anode 7a side, Equation 2 indicates a cathode electrode reaction on the cathode 7b side, and Equation 3 indicates a reaction occurring in the entire battery.

[0031]

[Formula 1] _{^{H 2 → 2H + + 2e -}} ... formula 1

Embedded image (1/2) O ₂ + 2H ⁺ + 2e ⁻ → H ₂ O Formula 2

Embedded image H ₂ + (１ ／) O ₂ → H ₂ O Formula 3 1-1-3. Hydrogen production device The hydrogen production device 2 includes a reformer 2a, a reformer burner 2b, and a hydrogen purifier 2c. The reformer 2a receives a supply of raw fuel from a liquid fuel tank 1 containing methanol and a water tank (not shown), performs reforming by a steam reforming method, and generates a hydrogen-rich fuel gas. . The supply of the raw fuel may be performed from the liquid fuel tank 1 storing a mixed liquid of methanol and water. Hereinafter, a reforming reaction performed inside the reformer 2a will be described.

[0032]

Embedded image CH ₃ OH → CO + 2H ₂ Formula 4

Embedded image CO + H ₂ O → CO ₂ + H ₂ Formula 5

CH ₃ OH + H ₂ O → CO ₂ + 3H ₂ Formula 6 The reforming reaction of methanol in the reformer 2a is a decomposition reaction of methanol represented by Formula 4 and a monoxide represented by Formula 5. The carbon conversion reaction proceeds simultaneously, and the reaction of Formula 6 occurs as a whole. Since such a reforming reaction is an endothermic reaction as a whole, heat must be supplied from the outside. For this reason, the reformer burner 2 for heating is provided inside the reformer 2a.
b is provided. Air from the air supply device 6 and fuel from the liquid fuel supply pump 11B are supplied to the reformer burner 2b, and the amount of heat required for the reforming reaction is obtained by combustion.

Then, the reformed gas discharged from the reformer 2a is
The hydrogen gas is supplied to a hydrogen purifier 2c installed downstream, purified and supplied as a hydrogen-rich fuel gas to the fuel cell main body 7 via a fuel supply path. In the fuel cell body 7,
Fuel gas is supplied to the anode 7a in each unit cell,
It is subjected to the anode electrode reaction shown in the above formula 1. In the case of the polymer electrolyte fuel cell, in particular, since it is poisoned by carbon monoxide, it is required to maintain low concentration of carbon monoxide in the fuel gas at the inlet of the fuel cell body 7. For this reason, although not shown in the hydrogen purifier 2c,
There is provided a hydrogen reduction device that injects a small amount of oxygen or air to make it tens of ppm or less.

1-1-4. Air Supply Device The air supply device 6 has a turbine 6 a rotating coaxially and a blower 6 b (blower or compressor), and supplies air taken in from outside to the fuel cell main body 7. Reformer burner 2b
A device that supplies air to the That is, the battery 8
When air and liquid fuel are supplied and ignited to the combustion burner 5 for the air supply device by the air supply blower 11A and the liquid fuel supply pump 11B operated by the electric power, the turbine 6a rotates, and the coaxial blower 6b is rotated. Has the function of sending out air. In the fuel cell main body 7, air is supplied to the cathode 7b in each unit cell, and is subjected to the cathode electrode reaction represented by the above equation (2).

The air supply blower 11A has a small capacity for the combustion burner 5 for the air supply device for heating the hydrogen storage alloy tank 3, which will be described later, and the fuel cell body 7
By separately providing two units, one for the reformer burner 2b of the hydrogen production apparatus 2 and the other for the reformer burner 2b, adjustment of the air supply amount and the like can be performed more easily and appropriately.

1-1-5. Battery Cooling Water Heat Exchanger The battery cooling water cooling heat exchanger 14 </ b> A is an air-cooled heat exchanger equipped with a radiator with a fan, and has a function of cooling the cooling water supplied to the cooling chamber 7 c of the fuel cell body 7. Having. The battery cooling water heating heat exchanger 14B is used as a heating source of the hydrogen storage alloy tank 3, and heats the battery cooling water by at least one of the exhaust gas of the combustion burner 5 for the air supply device and the exhaust gas of the reformer burner 2b. It has a function to do. The cooling water is sent from the water tank 13 by the battery cooling water circulation pump 12.

1-1-6. Hydrogen storage alloy tank The hydrogen storage alloy tank 3 is a tank that supplies hydrogen to the fuel cell main body 7, and has a temperature control device 4A for heating and cooling.
It has. The hydrogen storage alloy tank 3 is heated by supplying the exhaust gas from the combustion burner 5 for the air supply device to the temperature control device 4A when the power supply system is started. Further, the cooling water of the fuel cell main body 7 supplied to the temperature control device 4A can occlude hydrogen from the hydrogen production device 2 and refill it with hydrogen. Filling is possible. The cooling can be performed by a cooling device other than the cooling water of the fuel cell body 7.

1-1-7. Control device The control device 9 controls the flow control valves 15 to 25 for fuel, air, and the like according to a command from a driver or a command programmed in advance.
B, a starting device 10A, a power supply switching device 10B, an air supply blower 11A, a liquid fuel supply pump 11B, a battery cooling water circulation pump 12, a load device 26, and other devices. In particular, the output can be controlled by adjusting the supply amounts of the fuel gas and the air according to the size of the load device 26 connected to the power generation system. The control device 9 receives power supply from the battery 8 when the power supply system is started, and receives power supply from the fuel cell main body 7 after the fuel cell enters a power generation state.

1-1-8. Starting device The starting device 10A receives a command from the driver by the power from the battery 8 when the power supply system is started.
And has a function of activating the air supply blower 11A and the liquid fuel supply pump 11B, and igniting the combustion burner 5 for the air supply device and the reformer burner 2b.

1-1-9. Power supply switching device The power supply switching device 10B receives the supply of hydrogen from the hydrogen storage alloy tank 3 and the air from the air supply device 6 and, after the fuel cell main body 7 reaches the power generation state, operates the control device that is programmed in advance. It has a function of switching the power supply from the battery 8 to the fuel cell main body 7 according to a command.

1-1-10. Load Device The load device 26 receives a supply of electric power from the fuel cell main body 7 and generates a driving force. For example, in an electric vehicle equipped with the power supply system of the present embodiment, the load device 2
The axle is rotated by the motor of No. 6 to drive the vehicle. The load device 26 exchanges signals with the control device 9 so that the control device 9 issues a command in accordance with the load command of the driver and operates according to the command.

1-2. Operation The operation of the present embodiment as described above is as follows. That is, when the driver turns on the activation device 10A, the electric power stored in the battery 8 is supplied to the control device 9 via electric wiring (not shown), and the control device 9
Is activated. The control device 9 controls the command signal lines 27 and 28 according to the command received from the driver or the program.
A command is transmitted to the air supply blower 11A and the liquid fuel supply pump 11B via the air supply blower 11A to operate them, and the flow control valves 15, 17, 24, and 25A are opened. Then, the combustion burner 5 for the air supply device starts combustion by ignition of an ignition device (not shown).

The combustion exhaust gas of the combustion burner 5 for the air supply device is supplied to the temperature control device 4A of the hydrogen storage alloy tank 3 via the pipe via the turbine 6a side of the air supply device 6, and the hydrogen storage alloy is removed. It is heated and discharged out of the system.
Temperature at which the hydrogen storage alloy desorbs hydrogen (usually 100 ° C
Is heated, the hydrogen occluded in the hydrogen storage alloy tank 3 is discharged, and the hydrogen is released into the fuel cell main body 7.
Is supplied to the anode 7a. At the same time, the air supply device 6
The turbine 6a is operated by the high-temperature exhaust gas from the combustion burner 5 for the air supply device, and the coaxial blower 6b rotates. Then, the air supply device 6 sucks air from the atmosphere and supplies the air to the cathode 7b of the fuel cell main body 7 via the pipe.

Thus, receiving the supply of hydrogen and air,
Since the fuel cell main body 7 is in the power generation state, at that time (for example, about 0.5 minutes after the start-up), the power supply switching device 10B is operated by a pre-programmed command of the control device 9, and the power supply is changed to the battery 8 Is switched to the fuel cell main body 7, and the power supply system by the fuel cell main body 7 enters an autonomous operation state.

More specifically, as shown in FIGS. 4 and 5, almost simultaneously with the start-up (several tens of seconds), the hydrogen from the hydrogen storage alloy tank 3 and the air from the air supply device 6 are supplied to the fuel cell main body. 7 to reach the power generation state. In the figure, 61
Indicates the ratio of the amount of hydrogen released from the hydrogen storage alloy tank 3. Therefore, as shown at 64 in FIGS. 4 and 5, 100% load operation can be performed almost simultaneously with startup. Thereafter, as shown at 62 in FIG. 6, the output of the reformer 2a reaches a normal state after about 15 minutes, and is in a state where a hydrogen amount capable of operating at 100% load can be produced. At that time, as shown at 63 in FIG. 5, the hydrogen from the hydrogen storage alloy tank 3 is switched to the hydrogen-rich reformed gas from the hydrogen production device 2, so that the operation by the liquid fuel from the liquid fuel tank 1 is performed. Enter the transmission state. In addition, as shown by 61 and 62 in FIG. 5, a few minutes after the output of the reformer 2a is obtained, a part of the output is switched according to the output to gradually change the hydrogen supply source. It is also possible.

In parallel with this, in response to a command from the control device 9, the flow control valves 20, 21, 25 B are opened, and the air from the air supply device 6 flows from the supply pipe to the fuel cell body 7. The reformer burner 2b of the hydrogen production device 2 and the combustion burner 5 for the air supply device are connected via the branched pipe.
Supplied to Therefore, the capacity of the battery 8 is small enough to be used in a conventional automobile. If necessary, the battery 8 can receive power from the fuel cell main body 7 and be charged.

Even after the fuel cell body 7 is in the power generation state, the exhaust gas of the combustion burner 5 for the air supply device, which is the heating source of the hydrogen storage alloy tank 3, and the reformer burner until the target operating temperature is reached. The heat can be heated in the heat exchanger 14B by at least one of the exhaust gas of 2b.
Further, at the time of starting or at the time of keeping the temperature in a cold region during a stop, it is possible to heat the cooling water to raise the temperature to the operating temperature or to keep the temperature above the freezing temperature. When the temperature reaches the target temperature or higher, the temperature can be cooled by the radiator by the heat exchanger 14A and controlled to the target temperature.

By using the anode exhaust gas of the fuel cell body 7 as a heating source as fuel for the reformer burner 2b of the hydrogen production apparatus 2, energy efficiency can be improved. Also, the temperature of the hydrogen storage alloy tank 3 can be adjusted by opening the flow control valve 16.

Next, when stopping the operation of the power supply system, the reverse operation is performed. That is, the control device 9
When a driver's stop command is received, a command is issued to each device via command signal lines 27 and 28. Each component stops the supply of hydrogen, air, and cooling water to the fuel cell body 7 according to the command, so that the power generation stops.

However, the amount of hydrogen storage in the hydrogen storage alloy tank 3 is monitored, and if the amount of storage is insufficient, the operation of the hydrogen producing apparatus 2 is continued to store the required amount of hydrogen. The alloy tank 3 is filled. Further, during operation as a power source of an electric vehicle or the like, the hydrogen production apparatus 2 can be operated with an output larger than the actual load, and the surplus can be used for filling the hydrogen storage alloy tank 3. As described above, when the hydrogen supplied from the hydrogen production device 2 is stored in the hydrogen storage alloy, the hydrogen can be cooled to the storage temperature region by using the cooling water of the fuel cell body 7.

1-3. Effects The effects of the present embodiment as described above are as follows. That is, at the time of start-up, the supply of hydrogen from the hydrogen storage alloy tank 3 is received, and thereafter, the supply of hydrogen is switched to the supply of hydrogen from the hydrogen production device 2, so that the hydrogen supply is started at about 10
0% load operation can be realized and maintained continuously. Therefore, for example, in the case of a liquid fuel tank 1 of about 50 liters, the time that can be operated with one charge is 5 times as long as the conventional one.
The time can be equivalent to that of a 0 liter gasoline tank, and a traveling distance of 500 km or more can be achieved with an automobile power supply.

Further, as shown at 61 and 62 in FIG. 5, when control is performed to start switching after several minutes from when the output of the reformer 2a is obtained, the capacity of the hydrogen storage alloy can be reduced. it can. Therefore, for example, in the case of the above-described power supply for an automobile, the weight of the hydrogen storage alloy tank 3 is 50
A sufficient capacity is obtained with less than kg.

Further, as described above, the capacity of the battery 8 is small, and automatic filling can be performed during operation without removing the hydrogen storage alloy tank 3, so that the same operation as that of a conventional gasoline vehicle or the like can be performed. And a system that can be operated with the system. For example, even when the conventional ordinary small-capacity battery 8 uses the above-mentioned hydrogen storage alloy tank 3 of about 50 kg, power can be generated in a startup time of 1 minute or less.

Further, since each component such as the reformer 2a does not have a complicated structure, reliability in a long term is improved.

Further, the combustion burner 5 for the air supply device is
The means for operating the air supply device 6, the means for heating the hydrogen storage alloy tank, and the means for heating the heat exchanger 14B can also be used, and the heat exchanger 14B can be heated by the reformer burner 2b. Since the anode exhaust gas can be supplied to the container burner 2b, the exhaust heat can be efficiently used.

Further, the amount of hydrogen stored in the hydrogen storage alloy tank 3 can be kept at a level higher than the required amount for starting up by the filling operation as described above, so that hydrogen gas deficiency does not occur. Can be started at any time.

(2) Second embodiment 2-1. Configuration Another embodiment of the present invention will be described below with reference to FIG. That is, in the present embodiment, basically,
Although it is the same as the first embodiment shown in FIG. 1, the hydrogen storage alloy tank 3 according to the first embodiment is different from the first embodiment in the temperature control device 4A using the exhaust gas from the air supply device combustion burner 5 as a heat source. Temperature control device 4 with a burner for burning the liquid fuel supplied from the liquid fuel tank 1 by receiving the air supply from the air supply blower 11A.
B is different. Further, the exhaust gas from the air supply device 6 is provided so as to be directly supplied to the heat exchanger 14B of the battery cooling water, and the burner exhaust gas of the temperature control device 4B is also provided so as to be supplied to the heat exchanger 14B.

2-2. Operation and Effect The operation and effect of the present embodiment as described above are basically the same as those of the first embodiment.
Receives the air supplied from the air supply blower 11A and the liquid fuel supplied from the liquid fuel supply pump 11B, and heats the hydrogen storage alloy tank 3 by burning it with a burner to remove hydrogen. Can be supplied. Therefore, the temperature can be quickly raised to the target heating temperature, and stable temperature management can be realized.

Further, the cooling water can be heated in the heat exchanger 14B by using the exhaust gas of the combustion burner 5 for the air supply device. Furthermore, the exhaust gas from the reformer burner 2b of the hydrogen production device 2 and the burner exhaust gas from the temperature control device 4B of the hydrogen storage alloy tank 3 can be used together as a heating source for the fuel cell body 7. Thus, by diversifying the heating sources, the management of the heating temperature can be stabilized.

(3) Third Embodiment 3-1. Configuration Another embodiment of the present invention will be described below with reference to FIG. That is, the present embodiment is basically the same as the first embodiment shown in FIG. 1, but omits the air supply device 6 and removes the high-temperature exhaust gas from the combustion burner 5 for the air supply device. The difference is that the hydrogen storage alloy tank 3 is directly supplied to the temperature controller 4.

3-2. Operation and Effect According to the present embodiment as described above, the same operation and effect as those of the first embodiment can be obtained, and the omission of the air supply device 6 simplifies the system, reduces the cost and the installation space. Reduction can be achieved.

(4) Fourth Embodiment 4-1. Configuration Another embodiment of the present invention will be described. That is,
In the present embodiment, the temperature control device of the hydrogen storage alloy tank 3 is replaced by replacing the combustion burner 5 for the air supply device in the first embodiment shown in FIG. 4A is provided so that the exhaust gas from the reformer burner 2b can be supplied.

4-2. According to the present embodiment as described above, the same effects as those of the first embodiment can be obtained, and the combustion burner 5 for the air supply device can be omitted. Cost and installation space can be reduced.

(5) Other Embodiments The present invention is not limited to the above embodiments. For example, the capacities of the fuel cell body, the battery and the various tanks, and the number, type, size, and the like of the flow control valves and pipes can be appropriately changed. Further, the control device can be realized by a computer operated by a predetermined program, but can also be realized by a dedicated circuit.
Further, a magnetic recording medium, an optical recording medium, or any other recording medium in which a program for operating a computer according to the operating procedure as described in the above embodiment is recorded can be configured.

As the fuel cell body used in the present invention, a solid polymer electrolyte type fuel cell is most suitable, but is not necessarily limited thereto, and other types of fuel cells, for example, a phosphoric acid type Alternatively, a molten carbonate fuel cell may be used. Further, the fuel cell power supply system of the present invention
The present invention can be applied not only to a portable power source, an electric vehicle power source, a household power source, and a building power source but also to any other power source.

[0066]

As described above, according to the present invention, the fuel cell power supply system and the fuel cell power supply system capable of shortening the start-up time without using complicated equipment and securing a long operation time even with a small amount of fuel supply. A driving method can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a fuel cell power supply system according to the present invention.

FIG. 2 is a block diagram showing a second embodiment of the fuel cell power supply system of the present invention.

FIG. 3 is a block diagram showing a third embodiment of the fuel cell power supply system of the present invention.

FIG. 4 is a graph showing a change in the amount of hydrogen released from the hydrogen storage alloy tank according to the embodiment of the present invention.

FIG. 5 is a graph showing switching timing of a hydrogen supply source according to the embodiment of the present invention.

FIG. 6 is a graph showing a change in the output of the reformer according to the embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a conventional fuel cell power supply system.

FIG. 8 is a block diagram showing another example of a conventional fuel cell power supply system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Liquid fuel tank 2 ... Hydrogen production device 3 ... Hydrogen storage alloy tank 5 ... Combustion burner for air supply device 6 ... Air supply device 7 ... Fuel cell body 8 ... Battery 9 ... Control device 10A ... Start device 10B ... Power supply switching device 11A ... air supply blower 11B ... liquid fuel supply pump 12 ... battery cooling water circulation pump 13 ... water tank 14A, 14B ... heat exchanger 15-25B ... automatic switching valve 26 ... load 27-28 ... command signal line 29, 30 ... electricity wiring

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Rinzo Miyoshi 1-5-9 Shiba, Minato-ku, Tokyo Sumitomo Realty & Development Shiba Building No. 2 Toshiba Techno Consulting Co., Ltd. F-term (reference) 5H026 AA06 5H027 AA06 BA01 BA14 BA16 BC11 CC06 DD03 MM01 MM09 MM26

Claims (13)

[Claims] 1. A fuel cell main body, a hydrogen producing means for converting raw fuel into a hydrogen-rich gas by a reformer and supplying the same to the fuel cell main body, and a hydrogen storage means for storing the hydrogen gas supplied to the fuel cell main body And a fuel cell power supply system comprising: an air supply means for supplying air to the fuel cell body, wherein the hydrogen storage means is a hydrogen storage alloy tank having a hydrogen storage alloy capable of attaching and detaching hydrogen according to temperature. A fuel cell power supply system, comprising: a combustion burner for heating the hydrogen storage alloy tank directly or by exhaust gas. 2. The air supply means includes a turbine that rotates by exhaust gas from the combustion burner, and a blower that sends air to the fuel cell main body in conjunction with the turbine. A fuel cell power supply system as described. 3. The fuel cell according to claim 1, wherein the combustion burner is connected to the reformer such that the exhaust gas can heat the reformer. Power system. 4. The fuel cell main body is provided with a battery cooling unit for cooling with cooling water, cooling water supply means for supplying cooling water to the battery cooling unit is connected, and the hydrogen storage alloy tank is 3. The fuel cell power supply system according to claim 1, wherein said cooling water supply means is connected so as to be cooled by said cooling water. 5. A heating unit for heating cooling water is connected to the cooling unit, and the combustion burner is connected to the heating unit so that the exhaust gas serves as a heat source of the heating unit. The fuel cell power supply system according to any one of claims 1 to 4, wherein: 6. The cooling unit is connected to heating means for heating cooling water, and the reformer is provided with a reformer burner for directly supplying heat required for reforming. The fuel cell power supply system according to any one of claims 1 to 5, wherein the burner is connected to the heating means so that the exhaust gas serves as a heat source of the heating means. 7. The fuel cell power supply system according to claim 1, wherein the reformer is provided so as to be able to supply exhaust gas from the fuel cell body. 8. The reformer is provided with a reformer burner for directly supplying heat required for reforming, and the air supply means includes a small-capacity air supply blower for supplying air to the combustion burner. The fuel cell power supply system according to any one of claims 1 to 7, further comprising: a large-capacity air supply blower that supplies air to the reformer burner and the fuel cell body. 9. A battery, which is a power source of a device constituting the system at the time of startup, is provided, and a switching device for switching the power source to one of the battery and the fuel cell main body is provided. The fuel cell power supply system according to claim 1. 10. A combustion burner is used to heat the hydrogen storage alloy tank to supply hydrogen to the fuel cell main body, and to start power generation by supplying air from the air supply means to the fuel cell main body. In the hydrogen production means provided with a reformer, the reforming of the raw fuel is started, and after the reformer reaches a stage capable of supplying a hydrogen-rich gas capable of generating power in the fuel cell body, the hydrogen in the fuel cell body is An operation method of a fuel cell power supply system, wherein a supply source is switched to the hydrogen production means. 11. When starting up, a battery is used as a power source of a device constituting the system, and after the fuel cell main body is brought into a power generation state by hydrogen from the hydrogen storage alloy tank, the system is powered from the battery by the fuel. The method for operating a fuel cell power supply system according to claim 10, wherein the operation mode is switched to a battery main body. 12. The fuel cell power supply system according to claim 10, wherein a hydrogen-rich gas from the reformer is supplied into a hydrogen storage alloy tank before stopping the reformer. Driving method. 13. The method according to claim 10, wherein the reformer is operated in excess, and the hydrogen-rich gas generated by the excess operation is supplied to the water storage alloy tank. How to operate the fuel cell power supply system.