JP2009082810A - Insulating device and fuel cell system, and cooling method for insulated container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a time in an overheat state when an insulated container is overheated. <P>SOLUTION: A fuel cell system 50 comprises a reformer 71 reforming fuel into hydrogen, a catalytic combustor 73 heating the reformer 71, a fuel cell 59 generating electric power by the electrochemical reaction of hydrogen and oxygen generated in the reformer 71, the insulated container 3 accommodating the reformer 71 and the catalytic combustor 73, a second container 4 coming into contact with the insulated container 3, a water feeder 7 supplying water to the second container 4, a temperature sensor 11 detecting the temperature of the insulated container 3, and a control circuit 12 letting the water feeder 7 supply water when the temperature detected by the temperature sensor 11 becomes equal to or more than a predetermined threshold value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat insulating device, a fuel cell system, and a cooling method for a heat insulating container, and in particular, a heat insulating device used as a peripheral device of a fuel cell, a fuel cell system using the fuel cell, and a cooling method for cooling the heat insulating container used for them. About.

  In recent years, fuel cells have attracted attention as clean power sources with high energy conversion efficiency, and are being put to practical use in fuel cell vehicles and electrified houses. In addition, research and development using a fuel cell as a power source is also underway in portable electronic devices such as mobile phones and laptop computers (see, for example, Patent Document 1).

A fuel cell is a device that generates electricity by an electrochemical reaction between hydrogen and oxygen. Since hydrogen supplied to the fuel cell is generated from fuel such as methanol, a reformer or the like that generates hydrogen from fuel and water is connected to the fuel cell. In order to efficiently reform the fuel into hydrogen in the reformer, the reformer is heated with an electric heater or a combustor, and the reformer is housed in a heat insulating container together with its heat source ( For example, see Patent Document 2). The utilization efficiency of thermal energy is increased by accommodating the reformer or the like in the heat insulating container.
JP 2005-103399 A JP 2004-319467 A

By the way, there exists a possibility that a heat insulation container may be overheated for some reason.
Therefore, an object of the present invention is to make it possible to shorten the time of such an overheated state even if the heat insulating container is overheated.

In order to solve the above problems, according to the invention according to claim 1,
An insulated container containing a heat source that generates heat;
A second container arranged to be able to conduct heat from the heat insulating container;
An endothermic agent contained in the second container and reacting with water to absorb heat;
A water supply for supplying water to the second container;
A temperature detector for detecting the temperature of the insulated container;
A control unit that causes the water supply unit to supply water when the temperature detected by the temperature detection unit is equal to or higher than a predetermined threshold; and
A heat insulating device is provided that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.

According to the invention of claim 2,
The heat-insulating device according to claim 1, wherein the endothermic agent is enclosed in a capsule that is thermally melted or thermally sublimated.

According to the invention of claim 3,
An insulated container containing a heat source that generates heat;
A second container that is disposed so as to be capable of conducting heat from the heat insulating container and that contains water;
A capsule contained in the second container and thermally melted or sublimated;
An endothermic agent encapsulated in the capsule and reacts with water to absorb heat; and
A heat insulating device is provided that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.

According to the invention of claim 4,
The said heat insulation container and a said 2nd container contact | abut, The heat insulation apparatus as described in any one of Claims 1-3 characterized by the above-mentioned.

According to the invention of claim 5,
A reformer that reforms the fuel into hydrogen;
A heater that emits heat to heat the reformer;
A fuel cell that generates water by an electrochemical reaction between hydrogen and oxygen generated in the reformer and generates water;
An insulated container containing the reformer and the heater;
A second container arranged to be able to conduct heat from the heat insulating container;
An endothermic agent contained in the second container and reacting with water to absorb heat;
A water supply for supplying water to the second container;
A temperature detector for detecting the temperature of the insulated container;
A control unit that causes the water supply unit to supply water when the temperature detected by the temperature detection unit is equal to or higher than a predetermined threshold; and
A fuel cell system is provided that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.

According to the invention of claim 6,
6. The fuel cell system according to claim 5, wherein the endothermic agent is enclosed in a capsule that is thermally melted or thermally sublimated.

According to the invention of claim 7,
A water container for storing water;
The fuel cell system according to claim 5 or 6, wherein the water supply device supplies water in the water container to the second container.

According to the invention of claim 8,
8. The fuel cell system according to claim 7, wherein water contained in the off-gas of the fuel cell is accommodated in the water container.

According to the invention of claim 9,
The heater is a combustor that burns off-gas of the fuel cell;
The fuel cell system according to claim 7 or 8, wherein water contained in the gas delivered from the combustor is stored in the water container.

According to the invention of claim 10,
The fuel cell system according to any one of claims 7 to 9, wherein water contained in the off gas of the fuel cell is sent to the second container.

According to the invention of claim 11,
The heater is a combustor that burns off-gas of the fuel cell;
11. The fuel cell system according to claim 7, wherein water contained in the gas sent from the combustor is sent to the second container.

According to the invention of claim 12,
The fuel cell system according to any one of claims 5 to 11, wherein the heat insulating container and the second container are in contact with each other.

According to the invention of claim 13,
A reformer that reforms the fuel into hydrogen;
A heater that emits heat to heat the reformer;
A fuel cell that generates water by an electrochemical reaction between hydrogen and oxygen generated in the reformer and generates water;
An insulated container containing the reformer and the heater;
A second container that is disposed so as to be capable of conducting heat from the heat insulating container and that contains water;
A capsule contained in the second container and thermally melted or sublimated;
An endothermic agent encapsulated in the capsule and reacts with water to absorb heat; and
A fuel cell system is provided that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.

According to the invention of claim 14,
The heater is a combustor that burns off-gas of the fuel cell;
14. The fuel cell system according to claim 13, wherein water supplied to the second container is contained in the off gas or generated by combustion of the off gas.

According to the invention of claim 15,
The fuel cell system according to claim 13 or 14, wherein the heat insulating container and the second container are in contact with each other.

According to the invention of claim 16,
When the heat insulating container containing the heat source that generates heat is overheated, an endothermic reaction between the heat absorbing agent and water is caused in the second container arranged to be able to conduct heat from the heat insulating container, and heat is transferred from the heat insulating container to the second container. There is provided a method for cooling a heat insulating container.

According to the invention of claim 17,
The method for cooling a heat insulation container according to claim 16, wherein when the heat insulation container overheats, water is supplied into the second container to cause an endothermic reaction between the water and the endothermic agent. .

According to the invention of claim 18,
When the heat insulating container is overheated, the endothermic agent is enclosed and the capsule that is thermally melted or sublimated is melted or sublimated by the heat to cause an endothermic reaction of the endothermic agent and water. The cooling method of the heat insulation container of 16 or 17 is provided.

According to the invention of claim 19,
The method for cooling a heat insulation container according to any one of claims 16 to 18, wherein the heat insulation container and the second container are in contact with each other.

  According to the present invention, when the heat insulating container is overheated and its temperature becomes equal to or higher than the predetermined temperature, water is supplied to the second container. Then, the heat absorbing agent accommodated in the second container reacts with water and absorbs heat, and heat conduction from the heat insulating container to the second container causes the heat insulating container in contact with the second container to be cooled. Therefore, the time for which the heat insulating container is overheated can be minimized.

  Further, according to the present invention, when the heat insulating container is overheated and its temperature becomes equal to or higher than a predetermined temperature, the capsule in the second container is melted. The heat absorbing agent enclosed in the capsule reacts with the water in the second container to absorb heat and conducts heat from the heat insulating container to the second container, whereby the heat insulating container in contact with the second container is cooled. Therefore, the time for which the heat insulating container is overheated can be minimized.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

<First Embodiment>
FIG. 1 is a schematic sectional view showing the heat insulating device 1 together with the microreactor 2. FIG. 2 is a block diagram showing a configuration of a fuel cell system 50 using the heat insulating device 1 and the microreactor 2.

  The heat insulating device 1 includes a heat insulating container 3 containing the microreactor 2, a second container 4 in contact with the heat insulating container 3, a heat absorbing agent 5 housed in the second container 4, a water container 6 for storing water, A water supply device 7 for supplying water to the second container 4, a temperature sensor 11 for detecting the temperature of the heat insulating container 3, converting the detected temperature into an electrical signal, and inputting the detected temperature of the temperature sensor 11 and supplying water And a control circuit 12 for controlling the device 7.

  The heat insulating container 3 is a rigid container made of glass or metal. The space 13 in the heat insulating container 3 is evacuated and has a vacuum pressure (for example, 10 Pa or less, preferably 1 Pa or less), whereby the internal space 13 becomes a vacuum heat insulating layer. A radiation shield film such as gold is formed on the inner surface of the heat insulating container 3, whereby the radiation rate of the heat insulating container 3 is suppressed low, and heat radiation to the outside of the heat insulating container 3 is suppressed small. Note that the internal space 13 may be a heat insulating layer by filling the internal space 13 with a heat insulating gas having a low thermal conductivity such as a rare gas such as xenon.

  A temperature sensor 11 is attached to the outer surface of the heat insulating container 3. Although the temperature sensor 11 may be attached to the inner surface of the heat insulating container 3, it is preferable that the temperature sensor 11 is provided outside the heat insulating container 3 from the viewpoint of temperature measurement accuracy and from the viewpoint of wiring. .

  A microreactor (heat source) 2, which is a device that generates heat, is accommodated in the heat insulating container 3. The microreactor 2 includes a reformer 71 that reforms fuel into hydrogen, a carbon monoxide remover 72 that removes carbon monoxide mixed in the hydrogen generated in the reformer 71, a carbon monoxide remover 72, It has a catalytic combustor 73 that heats the reformer 71 with combustion heat, and temperature-dependent resistance heaters 74 to 76. Here, the catalytic combustor 73 is a heater that heats the reformer 71, and the temperature-dependent resistance heater 74 is also a heater that heats the reformer 71.

The reformer 71 generates hydrogen gas or the like from the vaporized water and fuel by a catalytic reaction, and further generates a carbon monoxide gas with a trace amount. That is, a flow path is formed inside the reformer 71, and a reforming catalyst (for example, a Cu / ZnO-based catalyst) is supported on the wall surface of the flow path. It flows through the flow path 71 and causes a reaction by the reforming catalyst. When the fuel is methanol, chemical reactions such as the following formulas (1) and (2) occur in the reformer 71.
CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ (1)
H ₂ + CO ₂ → H ₂ O + CO (2)

Hydrogen gas or the like generated by the reformer 71 is sent to the carbon monoxide remover 72, and external air is further sent to the carbon monoxide remover 72. The carbon monoxide remover 72 selectively removes carbon monoxide by preferentially oxidizing carbon monoxide with a catalyst. That is, a flow path is formed inside the carbon monoxide remover 72, and a selective oxidation catalyst (for example, platinum) is supported on the wall surface of the flow path, and is sent from the reformer 71 to the carbon monoxide remover 72. The hydrogen gas or the like mixed with air flows through the flow path of the carbon monoxide remover 72, and the carbon monoxide mixed with the hydrogen gas is preferentially oxidized by the selective oxidation catalyst as shown in the following formula (3). This produces carbon dioxide and removes carbon monoxide. Since the reaction of oxidizing carbon monoxide is an exothermic reaction, the carbon monoxide remover 72 is a device (heat source) that generates heat.
2CO + O ₂ → 2CO ₂ (3)

  The catalytic combustor 73 is supplied with hydrogen gas or the like mixed with air. The catalytic combustor 73 burns hydrogen with a catalyst. That is, a flow path is formed inside the catalytic combustor 73, a combustion catalyst (for example, platinum) is supported on the wall surface of the flow path, and the flow of the catalytic combustor 73 is mixed with hydrogen gas or the like. The hydrogen flows through the passage and is burned by the combustion catalyst, thereby generating combustion heat. The catalytic combustor 73 is also a device (heat source) that generates heat.

  The temperature at which the reforming reaction occurs in the reformer 71 is 280 to 400 ° C., and the temperature at which the selective oxidation reaction occurs in the carbon monoxide remover 72 is 100 to 180 ° C. In order to maintain such an appropriate temperature range, the installation position, shape, size, and the like of the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 are designed. Furthermore, the supply flow rate of combustion gas (specifically hydrogen) to the catalytic combustor 73, the supply flow rate of fuel and water to the reformer 71, and the like are adjusted. The reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 are provided with temperature dependent resistance heaters 74 to 76, and the reformer 71, carbon monoxide is heated by the electric heat of the temperature dependent resistance heaters 74 to 76. The remover 72 and the catalytic combustor 73 are heated, and the output power of the temperature dependent resistance heaters 74 to 76 is adjusted. Thereby, the temperature of the reformer 71 and the carbon monoxide remover 72 is maintained in an appropriate temperature range. The temperature-dependent resistance heaters 74 to 76 are made of an electric heating material whose electric resistance value depends on the temperature, and the temperature-dependent resistance heaters 74 to 76 also function as temperature sensors that read the temperature from the electric resistance value. The temperatures detected by the temperature-dependent resistance heaters 74 to 76 are used for closed-loop control of the temperatures of the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73. It should be noted that both heaters (for example, heating wires and ceramic heaters) and temperature sensors (for example, thermocouples and thermistors) are used without using the heaters and temperature sensors that are temperature-dependent resistance heaters 74 to 76. You may provide in the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73.

  The reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 are separated from the inner surface of the heat insulating container 3. Specifically, pipes 77 to 81 for passing reactants and products pass through the heat insulating container 3, and the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 are supported by the pipes 77 to 81. Thus, the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 are separated from the inner surface of the heat insulating container 3. In addition, a support member is used separately from the pipes 77 to 81 or in combination with the pipes 77 to 81, and the support member is provided between the reformer 71, the carbon monoxide remover 72, the catalytic combustor 73 and the heat insulating container 3. The reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 may be supported so as to be separated from the inner surface of the heat insulating container 3.

  The pipe 77 is for sending a mixture of water and fuel to the reformer 71, the pipe 79 is for sending air to the carbon monoxide remover 72, and the pipe 78 is for the carbon monoxide remover 72. The product having undergone the above is sent from the carbon monoxide remover 72, the pipe 80 is for sending a mixture of air and hydrogen etc. to the catalytic combustor 73, and the pipe 81 is passed through the catalytic combustor 73. The product is delivered from the catalytic combustor 73.

  The second container 4 is in contact with the heat insulating container 3 outside the heat insulating container 3. The second container 4 may be a rigid container or a flexible container. In FIG. 1, the outer surface of the heat insulating container 3 does not face the inner space 14 of the second container 4, but the second container 4 has an opening, and the opening is closed by the heat insulating container 3. A part of the outer surface may face the inner space 14 of the second container 4. Further, the second container 4 may be a laminate of a plurality of substrates, and the laminate may be formed with an internal space 14. Note that the second container 4 may be bonded to or in close contact with the heat insulating container 3 so as to be able to conduct heat between the second container 4 and the heat insulating container 3, or the second container 4 and the heat insulating container 3. A metal material may be sandwiched between the second container 4 and the heat insulating container 3 so as to be able to conduct heat.

  An endothermic agent 5 is accommodated in the second container 4. The endothermic agent 5 absorbs heat by reacting with water. The endothermic agent 5 is an ammonium salt (eg, ammonium sulfate, ammonium nitrate, ammonium bromide), an alkali metal salt (eg, sodium sulfate, sodium nitrate, potassium nitrate) or urea or a mixture thereof, preferably a mixture of ammonium nitrate and urea. . In the case of a mixture of ammonium nitrate and urea, the mixing ratio of ammonium nitrate is preferably 50 to 90% by weight, and the mixing ratio of urea is preferably 10 to 50% by weight. In FIG. 1, the endothermic agent 5 is in a powder form, but may be any of a powder form, a paste form, a granular form, and a fibrous form.

  Water 15 is stored in the water container 6 in a liquid state. The water container 6 and the second container 4 are connected by a pipe 18, and a pump 19 and a valve 20 are provided on the pipe 18. The valve 20 is an electrically driven open / close valve, the pump 19 is an electrically driven pump, and the valve 20 and the pump 19 are controlled by the control circuit 12. The water supply device 7 includes the pump 19 and the valve 20. When the pump 19 is operated with the valve 20 opened, the water in the water container 6 is supplied to the second container 4. Note that either the pump 19 or the valve 20 may be provided in the pipe 18. When the valve 20 is not provided and the pump 19 is provided, if the pump 19 is stopped, the water 15 in the water container 6 is not sent to the second container 4 and the pump 19 is operating. The water 15 in the water container 6 is sent to the second container 4. On the other hand, if the pump 19 is not provided and the valve 20 is provided, if the valve 20 is closed, the water in the water container 6 is not sent to the second container 4 and the valve 20 is open. Water in the water container 6 is sent to the second container 4 due to its own weight or capillary action.

  The water 15 may be stored in the water container 6 in advance, or may be generated and liquefied in each part of the fuel cell system 50 shown in FIG. A process in which the water 15 is generated will be described in detail with reference to FIG.

  As shown in FIG. 2, the fuel cell system 50 includes a fuel cartridge 51, a vaporizer 53, a fuel cell 59 and the like in addition to the microreactor 2 and the heat insulating device 1. The control circuit 12 controls the heat insulating device 1 and also controls the fuel cell system 50.

  The fuel cell system 50 is mounted on electronic devices such as notebook personal computers, PDAs, electronic notebooks, digital cameras, mobile phones, watches, registers, projectors, and the like. Among the components shown in FIG. 2, the fuel cartridge 51 can be attached to and detached from the electronic device body, the other components are built in the electronic device body, and the fuel cartridge 51 is attached to the electronic device body. The cartridge 51 and the fuel pump 52 are connected.

  The fuel cartridge 51 stores liquid fuel (for example, methanol, ethanol, dimethyl ether). The fuel cartridge 51 may store a liquid mixture of liquid fuel and water.

  The fuel pump 52 sucks liquid fuel from the fuel cartridge 51 and sends the sucked liquid fuel to the vaporizer 53. The fuel pump 52 is an electrically driven pump, and the operation / stop / speed of the fuel pump 52 is controlled by the control circuit 12.

  The liquid fuel sent out from the fuel pump 52 is mixed with water and sent to the vaporizer 53. The water mixed with the liquid fuel is water in the water container 6. That is, the water in the water container 6 is sucked up by the pump 60 and sent to the vaporizer 53. If the liquid fuel in the fuel cartridge 51 is mixed with water, the pump 60 may be omitted. Instead of using the water in the water container 6, the water in another water container may be sent to the vaporizer 53 by the pump 60, and the other water container is similar to the fuel cartridge 51 in the electronic device main body. May be removable.

  The pump 60 is an electrically driven pump, and the operation / stop / speed of the pump 60 is controlled by the control circuit 12.

  The vaporizer 53 vaporizes a mixed liquid of fuel and water. The vaporizer 53 is provided with an electric heater made of an electric heating material, and the liquid mixture sent to the vaporizer 53 is evaporated by the heat of the electric heater. The air-fuel mixture vaporized by the vaporizer 53 is sent to the reformer 71.

  Hydrogen gas or the like generated through the reformer 71 and the carbon monoxide remover 72 is sent to the fuel cell 59. The fuel cell 59 includes an anode 58, a cathode 56, and an electrolyte membrane 57 sandwiched between the anode 58 and the cathode 56. Hydrogen gas or the like sent from the carbon monoxide remover 72 is sent to the anode 58, and external air is sent to the cathode 56. The hydrogen supplied to the anode 58 undergoes an electrochemical reaction with oxygen in the air supplied to the cathode 56 via the electrolyte membrane 57, thereby generating electric power between the anode 58 and the cathode 56.

When the electrolyte membrane 57 is a hydrogen ion permeable electrolyte membrane (for example, a solid polymer electrolyte membrane), hydrogen ions generated at the anode 58 permeate the electrolyte membrane 57, and at the cathode 56, the following formula (5) is satisfied. Such a reaction occurs.
H ₂ → 2H ⁺ + 2e ⁻ (4)
2H ⁺ + 1 / 2O ₂ + 2e ⁻ → H ₂ O (5)

On the other hand, when the electrolyte membrane 57 is an oxygen ion permeable electrolyte membrane (for example, a solid oxide electrolyte membrane), a reaction of the following formula (6) occurs at the cathode 56, and oxygen ions generated at the cathode 56 are generated. Passes through the electrolyte membrane 57, and the anode 58 undergoes a reaction of the following formula (7).
1 / 2O ₂ + 2e ⁻ → 2O ²⁻ (6)
H ₂ + 2O ²⁻ → H ₂ O + 2e ⁻ (7)
In the case where the electrolyte membrane 57 is a solid oxide electrolyte membrane, the carbon monoxide remover 72 may not be provided. In this case, the hydrogen gas generated by the reformer 71 is sent to the anode 58 as it is, and the fuel cell. 59 is accommodated in the heat insulating container 3 together with the reformer 71.

  Electric power generated between the anode 58 and the cathode 56 of the fuel cell 59 is stored in the power storage unit 62. The power storage unit 62 is, for example, a secondary battery. The generated electric power is stored in the power storage unit 62, supplied to the various actuators, heaters, and circuits shown in FIG. 2, and further supplied to the electronic device main body.

  Hydrogen gas or the like (off gas) remaining without an electrochemical reaction at the anode 58 is sent to the catalytic combustor 73. Further, external air is mixed with unreacted hydrogen gas and sent to the catalytic combustor 73. As described above, in the catalytic combustor 73, hydrogen is burned by the catalyst, and water is generated.

  In order to supply air to the carbon monoxide remover 72, the cathode 56 and the catalytic combustor 73, an air pump 54 and a flow control valve 55 are provided. The air pump 54 sends external air to the carbon monoxide remover 72, the cathode 56, and the catalytic combustor 73, and the flow rate control valve 55 controls the flow rate of air sent by the air pump 54. The air pump 54 and the flow rate control valve 55 are electrically driven, and the air pump 54 and the flow rate control valve 55 are controlled by the control circuit 12. A blower may be used instead of the air pump 54.

  As described above, water is generated in the reformer 71, the cathode 56, the anode 58, the catalytic combustor 73, and the like. Since the produced water is gaseous or vaporous, a condenser 61 is provided to liquefy the water. In FIG. 2, a condenser 61 is provided downstream of the cathode 56 of the fuel cell 59 and the catalytic combustor 73. Therefore, the water generated by the reformer 71, the cathode 56, the anode 58, the catalytic combustor 73, etc. is sent to the condenser 61 together with other products. Then, the water is cooled in the condenser 61 and liquefied.

  The water liquefied by the condenser 61 is sent to the water container 6 together with other products and stored in the water container 6. Then, water is circulated by the pump 60.

  As shown in FIG. 1, an outlet hole 16 is formed in the water container 6, and the outlet hole 16 is closed by a gas-liquid separation membrane 17. The gas-liquid separation membrane 17 has gas permeability and liquid blocking properties. Therefore, the water liquefied by the condenser 61 stays in the water container 6, but the gas passes through the gas-liquid separation membrane 17 and is discharged to the outside.

  The place where the condenser 61 is provided is not limited to the downstream of the cathode 56 and the catalytic combustor 73. For example, the condenser 61 may be provided between the anode 58 and the catalytic combustor 73, or the condenser 61 is provided between the reformer 71 and the carbon monoxide remover 72 and outside the heat insulating container 3. These condensers 61 may be used in combination. When the condenser 61 is provided between the reformer 71 and the carbon monoxide remover 72, the water container 6 is provided between the condenser 61 and the carbon monoxide remover 72, and the outlet hole 16 is provided via a pipe or the like. To the carbon monoxide remover 72. Therefore, water liquefied by the condenser 61 (mainly, unreacted water in the reformer 71) is stored in the water container 6, but a gas such as hydrogen gas passes through the gas-liquid separation membrane 17 to It is sent to the carbon oxide remover 72. When the condenser 61 is provided between the anode 58 and the catalytic combustor 73, the water container 6 is provided between the condenser 61 and the catalytic combustor 73, and the outlet hole 16 is connected to the catalytic combustor 73 via a pipe or the like. Communicates. Therefore, water liquefied by the condenser 61 is stored in the water container 6, but a gas such as hydrogen gas passes through the gas-liquid separation film 17 and is sent to the catalytic combustor 73.

  The path shown in FIG. 2 may be configured by a micropipe or a microhose, or may be configured by stacking a plurality of substrates on which grooves, holes, slits, or the like are formed. Here, by laminating a plurality of substrates, the grooves, holes, slits and the like are covered with the substrate, and the grooves, holes, slits and the like serve as flow paths, and the path shown in FIG. 2 is formed.

The control circuit 12 includes a CPU, a RAM, a ROM, and the like. The control circuit 12 controls the fuel pump 52, the carburetor 53, the air pump 54, the pumps 19 and 60, the flow control valve 55, the valve 20, and the temperature dependent resistance heaters 74 to 76. The control circuit 12 performs closed-loop control based on the temperature-dependent resistance heaters 74 to 76 and the temperature detected by the temperature sensor 11 in these controls.
The interface 63 performs data transfer between the control circuit 12 and the control unit of the electronic device main body.

Next, the control operation of the control circuit 12 and the operation of the heat insulating device 1 and the fuel cell system 50 associated therewith will be described.
The control circuit 12 supplies electric power to the electric heaters and temperature dependent resistance heaters 74 to 76 of the vaporizer 53 and drives the pumps 52 and 60 and the air pump 54. Here, based on the temperature detected by the temperature dependent resistance heaters 74 to 76, the control circuit 12 supplies power to the electric heaters and temperature dependent resistance heaters 74 to 76 of the vaporizer 53, the operating speed of the pump 52, and the pump 60. And the flow rate of the flow rate control valve 55 are closed-loop controlled.

  Thereby, the liquid fuel and water are vaporized in the vaporizer 53, the fuel is reformed into hydrogen in the reformer 71, the carbon monoxide is removed in the carbon monoxide remover 72, and power generation occurs in the fuel cell 59, Unreacted hydrogen or the like is combusted in the catalyst combustor 73, water is condensed in the condenser 61, the condensed water is stored in the water container 6, and the exhaust gas passes through the gas-liquid separation membrane 17 and is discharged.

  As described above, when reactants and products flow and power generation occurs in the fuel cell 59, the temperature of the heat insulating container 3 is detected by the temperature sensor 11, and a signal indicating the detected temperature is input to the control circuit 12. Has been.

  When the vaporizer 53, the reformer 71, the carbon monoxide remover 72, the catalytic combustor 73, the fuel cell 59, etc. operate constantly and power generation is occurring, the temperature of the heat insulating container 3 is maintained at about 40 ° C. I'm leaning. Therefore, the level of the temperature signal input from the temperature sensor 11 to the control circuit 12 corresponds to about 40 ° C. Here, the control circuit 12 compares the temperature detected by the temperature sensor 11 with a predetermined threshold value α. The threshold value α partitions the overheated state of the heat insulating container 3 from the unheated state, and its value is 100 ° C., for example. If the detected temperature is lower than the threshold value α as a result of the comparison, the control circuit 12 keeps the pump 19 stopped and closes the valve 20. Further, the control circuit 12 supplies power to the electric heater and temperature-dependent resistance heaters 74 to 76 based on the temperature detected by the temperature-dependent resistance heaters 74 to 76, the operating speed of the pump 52, and the operation of the pump 60. Control of the flow rate of the speed and flow rate control valve 55 is continued. Therefore, power generation continues.

  On the other hand, when the degree of vacuum in the heat insulating container 3 decreases, or when the reformer 71, the carbon monoxide remover 72, and the catalytic combustor 73 reach a high temperature that deviates from the steady state to some extent, the temperature of the heat insulating container 3 increases. It rises. Under such circumstances, when the heat insulation container 3 is overheated and the temperature of the heat insulation container 3 becomes equal to or higher than the threshold value α, the control circuit 12 determines that the temperature detected by the temperature sensor 11 is equal to or higher than the threshold value α.

When the temperature detected by the temperature sensor 11 is equal to or higher than the threshold value α, the control circuit 12 stops the fuel pump 52, the pump 60, and the air pump 54, and also stops the power supply to the temperature dependent resistance heaters 74 to 76. Further, the control circuit 12 opens the valve 20 and drives the pump 19. When the pump 19 is activated, the water 15 in the water container 6 is supplied to the second container 4, and the endothermic agent 5 and the water 15 are mixed in the second container 4. Then, the endothermic agent 5 reacts with the water 15 and absorbs heat. The heat insulation container 3 is cooled by conducting heat from the heat insulation container 3 to the second container 4.
If the overheated state of the heat insulating container can be suppressed by conducting heat from the heat insulating container to the second container, the second container and the heat insulating container do not need to be in direct contact with each other. And the heat insulating container may be bonded with an adhesive. Further, the second container and the heat insulating container are arranged close to each other so as to be able to conduct heat, or another member having a higher thermal conductivity than air is interposed between the second container and the heat insulating container. Also good.

  The fuel cell system 50 is optimally designed so that the degree of vacuum in the heat insulating container 3 does not decrease, or the reformer 71 or the like does not reach a high temperature that deviates to some extent from each steady state. However, even if the heat insulation container 3 is overheated, the heat insulation container 3 is urgently cooled by the endothermic reaction of the endothermic agent 5, so that the time during which the heat insulation container 3 is overheated is minimized. Can be suppressed.

  In addition, the water 15 used for the endothermic reaction of the endothermic agent 5 is water generated by the fuel cell 59 or the catalytic combustor 73, and therefore it is not necessary to prepare water separately. In particular, since the water in the water container 6 is circulated for the reforming reaction, and the circulating water is used for the endothermic reaction of the endothermic agent 5, the configuration of the fuel cell system 50 is complicated. Don't be.

<Second Embodiment>
FIG. 3 is a schematic cross-sectional view showing the heat insulating device 1 </ b> A together with the microreactor 2. FIG. 4 is a block diagram showing a configuration of a fuel cell system 50A using the heat insulating device 1A and the microreactor 2. Components corresponding to each other between FIGS. 1-2 and 3-4 are denoted by the same reference numerals. Components corresponding to each other between FIGS. 1-2 and 3-4 are similarly provided except as described below.

  In the heat insulating device 1 </ b> A shown in FIGS. 3 to 4, the endothermic agent 5 is enclosed in a heat-meltable capsule 25. The capsule 25 in which the endothermic agent 5 is enclosed is accommodated in the second container 4.

  The melting point of the capsule 25 is equal to or higher than the temperature (threshold α: for example, 100 ° C.) at which the pump 19 operates in the first embodiment. The capsule 25 is made of a water-insoluble material. Specifically, the capsule 25 is made of a water-affinity natural polymer made of at least one selected from starches, gelatins and agars. The capsule 25 may be made of a sublimation agent that sublimes by heat, and the sublimation temperature is equal to or higher than the threshold value α.

  Unlike the heat insulation device 1 shown in FIGS. 1 to 2, the heat insulation device 1 </ b> A shown in FIGS. 3 to 4 is not provided with the water supply unit 7 or the pipe 18, so that the water in the water container 6 is not contained. It is not supplied to the second container 4. Instead, water 26 is stored in the second container 4. The water 26 may be stored in the second container 4 in advance, or may be generated and liquefied in each part of the fuel cell system 50A shown in FIG. The case where the produced water produced | generated by each part of 50 A of fuel cell systems is stored as the water 26 in the 2nd container 4 is demonstrated using FIG.

  The second container 4 is provided downstream of the condenser 61 and upstream of the water container 6. Therefore, the water liquefied by the condenser 61 is sent to the second container 4 together with other products and stored in the second container 4. Further, a part of the water liquefied by the condenser 61 is not stored in the second container 4 but is also sent to the water container 6 together with other products. In this way, water contained in the off gas of the cathode 56 of the fuel cell 59 is accommodated in the water container 6 through the condenser 61 and the second container 4. Water contained in the gas delivered from the catalytic combustor 73 is also accommodated in the water container 6 via the condenser 61 and the second container. Then, water is circulated by the pump 60.

  As shown in FIG. 3, the inner diameter of the pipe 27 connecting the second container 4 and the condenser 61 is smaller than the diameter of the capsule 25, and the inner diameter of the pipe 28 connecting the second container 4 and the water container 6 is also capsule. Less than 25 diameters. Therefore, the capsule 25 in the second container 4 does not flow out of the second container 4.

Next, the control operation of the control circuit 12, and the operation of the heat insulating device 1A and the fuel cell system 50A associated therewith will be described.
During power generation, the control of the control circuit 12 is the same as in the first embodiment. Therefore, the liquid fuel and water are vaporized in the vaporizer 53, the fuel is reformed into hydrogen in the reformer 71, the carbon monoxide is removed in the carbon monoxide remover 72, the power generation occurs in the fuel cell 59, and the catalyst Unreacted hydrogen or the like is combusted in the combustor 73, water is condensed in the condenser 61, the condensed water is stored in the second container 4 or the water container 6, and the exhaust gas passes through the gas-liquid separation film 17. Discharged.

  When the temperature of the heat insulating container 3 rises during power generation and the temperature detected by the temperature sensor 11 becomes equal to or higher than the threshold value α, the control circuit 12 stops the fuel pump 52, the pump 60, and the air pump 54, and depends on the temperature. The power supply to the resistive heaters 74 to 76 is also stopped.

On the other hand, as the temperature of the heat insulating container 3 increases, the temperature of the second container 4 and the water 26 / capsule 25 inside also increase. And when the heat insulation container 3 overheats, the capsule 25 will fuse | melt. Then, the endothermic agent 5 in the capsule 25 reacts with the water 26 and absorbs heat. The heat insulating container 3 is cooled by exchanging heat between the second container 4 and the heat insulating container 3.
If the overheated state of the heat insulating container can be suppressed by conducting heat from the heat insulating container to the second container, the second container and the heat insulating container do not need to be in direct contact with each other. And the heat insulating container may be bonded with an adhesive. Further, the second container and the heat insulating container are arranged close to each other so as to be able to conduct heat, or another member having a higher thermal conductivity than air is interposed between the second container and the heat insulating container. Also good.

As described above, in the present embodiment, the water supply device 7, the pipe 18, and the temperature sensor 11 are unnecessary, so that the fuel cell system can be simplified. Moreover, since heat absorption is automatically performed as the temperature of the heat insulating container 3 rises, electrical control is unnecessary, and when the heat insulating container 3 is overheated, cooling can be performed more reliably.
Since it is conceivable that the water 26 stored in the second container 4 is small, as shown in FIG. 5, as in the case of the first embodiment, the water supplier 7 and the pipe 18 are provided, and the temperature When the temperature detected by the sensor 11 is equal to or higher than the threshold value α, the control circuit 12 controls the water supplier 7 so that the water in the water container 6 is supplied to the second container 4 by the water supplier 7. Also good.

  Even in this embodiment, even if the heat insulating container 3 is overheated, the heat insulating container 3 is urgently cooled by the endothermic reaction of the heat absorbing agent 5 that has come out of the capsule 25. It is possible to minimize the time when the is overheating. Further, since the water 26 in the second container 4 is water generated by the fuel cell 59 and the catalytic combustor 73, it is not necessary to prepare water separately.

In addition, this invention is not limited to said each embodiment, You may make a various design change with respect to said each embodiment.
For example, the reformer 71, the carbon monoxide remover 72, and the catalyst combustor 73 may be housed in a heat insulation container different from the heat insulation container 3, and the fuel cell 59 may be housed in the heat insulation container 3. Even when the fuel cell 59 is housed in the heat insulating container 3, the fuel cell 59 generates heat due to an electrochemical reaction between hydrogen and oxygen, so that the fuel cell 59 becomes a high temperature that deviates to some extent from its steady state. When the container 3 is overheated, the endothermic agent 5 accommodated in the second container 4 and water are cooled by an endothermic reaction, and heat is exchanged between the second container 4 and the heat insulating container 3, thereby The heat insulating container 3 is cooled as in the case of the embodiment or the second embodiment.

FIG. 1 is a cross-sectional view showing the heat insulating device according to the first embodiment together with a microreactor. FIG. 2 is a block diagram showing a configuration of a fuel cell system using the heat insulating device shown in FIG. FIG. 3 is a cross-sectional view showing the heat insulating device according to the second embodiment together with the microreactor. FIG. 4 is a block diagram showing a configuration of a fuel cell system using the heat insulating device shown in FIG. FIG. 5 is a block diagram showing a configuration of a fuel cell system using a heat insulating device according to a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A heat insulation apparatus 2 Microreactor 3 Heat insulation container 4 2nd container 5 Endothermic agent 6 Water container 7 Water supply device 11 Temperature sensor 12 Control circuit 15, 26 Water 25 Capsule 50, 50A Fuel cell system 59 Fuel cell 71 Reformer 72 Carbon monoxide remover 73 Catalytic combustor 74 to 76 Temperature dependent resistance heater

Claims (19)

An insulated container containing a heat source that generates heat;
A second container arranged to be able to conduct heat from the heat insulating container;
An endothermic agent contained in the second container and reacting with water to absorb heat;
A water supply for supplying water to the second container;
A temperature detector for detecting the temperature of the insulated container;
A control unit that causes the water supply unit to supply water when the temperature detected by the temperature detection unit is equal to or higher than a predetermined threshold; and
A heat insulating device that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.   The heat insulating device according to claim 1, wherein the endothermic agent is sealed in a capsule that is thermally melted or thermally sublimated. An insulated container containing a heat source that generates heat;
A second container that is disposed so as to be capable of conducting heat from the heat insulating container and that contains water;
A capsule contained in the second container and thermally melted or sublimated;
An endothermic agent encapsulated in the capsule and reacts with water to absorb heat; and
A heat insulating device that conducts heat from the heat insulating container to the second container when the heat absorbing agent absorbs heat.   The said heat insulation container and the said 2nd container contact | connect, The heat insulation apparatus as described in any one of Claims 1-3 characterized by the above-mentioned. A reformer that reforms the fuel into hydrogen;
A heater that emits heat to heat the reformer;
A fuel cell that generates water by an electrochemical reaction between hydrogen and oxygen generated in the reformer and generates water;
An insulated container containing the reformer and the heater;
A second container arranged to be able to conduct heat from the heat insulating container;
An endothermic agent contained in the second container and reacting with water to absorb heat;
A water supply for supplying water to the second container;
A temperature detector for detecting the temperature of the insulated container;
A control unit that causes the water supply unit to supply water when the temperature detected by the temperature detection unit is equal to or higher than a predetermined threshold; and
The fuel cell system, wherein the heat absorbing agent absorbs heat and conducts heat from the heat insulating container to the second container.   6. The fuel cell system according to claim 5, wherein the endothermic agent is enclosed in a capsule that is thermally melted or thermally sublimated. A water container for storing water;
The fuel cell system according to claim 5 or 6, wherein the water supplier supplies water in the water container to the second container.   The fuel cell system according to claim 7, wherein water contained in the off-gas of the fuel cell is stored in the water container. The heater is a combustor that burns off-gas of the fuel cell;
The fuel cell system according to claim 7 or 8, wherein water contained in the gas sent from the combustor is stored in the water container.   The fuel cell system according to any one of claims 7 to 9, wherein water contained in the off-gas of the fuel cell is sent to the second container. The heater is a combustor that burns off-gas of the fuel cell;
11. The fuel cell system according to claim 7, wherein water contained in the gas sent from the combustor is sent to the second container.   The fuel cell system according to any one of claims 5 to 11, wherein the heat insulating container and the second container are in contact with each other. A reformer that reforms the fuel into hydrogen;
A heater that emits heat to heat the reformer;
A fuel cell that generates water by an electrochemical reaction between hydrogen and oxygen generated in the reformer and generates water;
An insulated container containing the reformer and the heater;
A second container that is disposed so as to be capable of conducting heat from the heat insulating container and that contains water;
A capsule contained in the second container and thermally melted or sublimated;
An endothermic agent encapsulated in the capsule and reacts with water to absorb heat; and
The fuel cell system, wherein the heat absorbing agent absorbs heat and conducts heat from the heat insulating container to the second container. The heater is a combustor that burns off-gas of the fuel cell;
The fuel cell system according to claim 13, wherein the water supplied to the second container is contained in the off-gas or generated by combustion of the off-gas.   The fuel cell system according to claim 13 or 14, wherein the heat insulating container and the second container are in contact with each other.   When the heat insulating container containing the heat source that generates heat is overheated, an endothermic reaction between the heat absorbing agent and water is caused in the second container arranged to be able to conduct heat from the heat insulating container, and heat is transferred from the heat insulating container to the second container. A method for cooling a heat insulating container.   The method for cooling a heat insulation container according to claim 16, wherein when the heat insulation container is overheated, water is supplied into the second container to cause an endothermic reaction between the water and the endothermic agent.   When the heat insulating container is overheated, the endothermic agent is enclosed and the capsule that is thermally melted or sublimated is melted or sublimated by the heat to cause an endothermic reaction of the endothermic agent and water. The cooling method of the heat insulation container of 16 or 17.   The method for cooling a heat insulation container according to any one of claims 16 to 18, wherein the heat insulation container and the second container are in contact with each other.

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