JP2007063113A - Hydrogen generation apparatus and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system having high energy density. <P>SOLUTION: The system is provided with a reaction part 10 for housing a material for hydrogen reaction and also for reacting the material for hydrogen reaction with a hydrogen generating aqueous solution, a liquid storing part 11 for storing the hydrogen generating aqueous solution, supply lines 15a, 15b for supplying the stored hydrogen generating aqueous solution 17 in the liquid storing part 11 to the reaction part 10, and a discharge means 3 for discharging the hydrogen generated in the reaction part 10, wherein the pressure within the reaction part 10 is allowed to pressurize the hydrogen generating aqueous solution 17 within the liquid storing part 11, and an opening and closing means 14 that opens and closes the flow passage according to the pressure condition is provided in a midway of the supply line 15a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hydrogen generation facility and a fuel cell system with improved energy density, and in particular, can control the amount of hydrogen generation aqueous solution charged into a reaction section that causes a hydrogen generation reaction without using power consumption, and The present invention relates to a technique for increasing the input amount of an aqueous solution for hydrogen generation according to the amount of power generation.

  Due to the recent increase in energy and environmental problems, there is a demand for a power source with higher energy density and clean emissions. A fuel cell is a generator having an energy density several times that of an existing cell, has high energy efficiency, and is characterized by no or little nitrogen oxides and sulfur oxides contained in exhaust gas. Therefore, it is said that it is a very effective device that meets the demand as a next-generation power supply device.

  The electrode reaction in the fuel cell is a water production reaction by hydrogen and oxygen. Accordingly, it is necessary to introduce hydrogen into the fuel cell, and hydrogen storage materials and mechanisms for reducing the energy required for hydrogen generation and hydrogen amount control have been developed.

  Conventionally, a metal hydride (for example, sodium borohydride) called chemical hydride is known as a hydrogen storage material having a high amount of hydrogen in the reaction product (hereinafter referred to as hydrogen storage density). The hydrogen generation reaction is a reaction in which a metal hydride and water are mixed and hydrolyzed, and since the reaction proceeds rapidly at room temperature, the energy for generating hydrogen is very low. That is, it can be said that metal hydrides are more advantageous than other hydrogen storage materials from the viewpoint of hydrogen storage density and hydrogen generation energy.

  Examples of conventional methods for efficiently generating hydrogen from such metal hydrides include, for example, a method in which a catalyst is brought into contact with an alkali aqueous solution of metal hydride, and a method in which a solid of metal hydride and water are held in the same container. is there. In any case, hydrogen can be generated with low energy, but there are problems from the viewpoint of controllability of reaction amount and long-term storage. In the former, it is difficult to control the amount of hydrogen generated, and since the metal hydride and water are always in contact with each other, hydrogen is gradually decomposed to generate hydrogen. In the latter case, the inside of the container is always wet, and there is a weak point that metal hydride is hydrolyzed by water vapor or splashes to generate hydrogen.

  In order to solve this problem, a structure has been proposed in which a necessary amount of water is appropriately supplied to a metal hydride when necessary (see, for example, Patent Document 1). This is a hydrogen generator consisting of a reaction section holding a metal hydride, a water tank storing water, and a pump for sending water to the reaction section. Water is supplied to the metal hydride in the reaction section by a pump. It is a device that brings both into contact and causes a hydrogen generation reaction. By separating the reaction part and the water tank, there is an advantage that the metal hydride does not come into contact with water when the fuel cell is stopped, and the hydrogen generation reaction does not occur.

JP 2002-137903 A (page 4-6, FIG. 1)

  However, even in the case of using a metal hydride having a high hydrogen storage density and low hydrogen generation energy, the conventional method consumes electric power for liquid feeding because the water is pumped by a pump. It was supposed to be. As a result, the net output of the fuel cell system is reduced. Therefore, it is a problem to obtain a structure that does not use electric power for feeding water.

  Furthermore, the pump of liquid feeding has a large volume, which has been a major factor in reducing the volume energy density of the fuel cell system. Therefore, it is a problem to obtain a structure capable of feeding liquid with a small volume.

  Furthermore, from the standpoint of the fuel cell system, there is a serious problem that the amount of metal hydride input is extremely small compared to the total volume, and therefore it is difficult to increase the energy density practically.

  The cause of the reduced amount of metal hydride input is the form of the reaction product. That is, when the reaction is performed at a desired reaction rate, foaming occurs, and the foam entrains the reactants, reaction products, and residues, and the volume expands. Therefore, when there is not enough space in the reaction part, the reactants, reaction products, and residues leak out of the reaction part. Since the expansion coefficient of the volume is determined by the reaction amount, the required space volume can be determined from the mass of the reactant, and conversely, the amount of metal hydride that can be charged can be determined from the volume of the reaction section. At present, even if estimated to the maximum, the volume of the metal hydride can be charged only about 8.5% of the reactor volume.

  Further, the conventional hydrogen generator with improved reaction controllability is an apparatus composed of a reaction part and a liquid storage part such as a water tank, and the liquid storage part needs a volume equivalent to that of the reaction part. Therefore, the volume of the metal hydride is about 4% of the entire hydrogen generator.

  From the above, it is necessary to effectively use the space in the hydrogen generator and reduce the dead space. In the conventional structure, when water is supplied from the liquid storage unit to the reaction unit, the inside of the water tank becomes empty. The empty space in the liquid storage part cannot be used and becomes a dead space. The problem is to improve the energy density by effectively utilizing the dead space generated in such a liquid storage section.

  As described above, the present invention can move the aqueous solution for hydrogen generation without using electric power to cause a hydrogen generation reaction, and reduce the dead space of the liquid storage unit, thereby generating high energy density hydrogen. An object is to provide a facility and a fuel cell system.

  A first aspect of the present invention that solves the above-described problem is that a hydrogen reaction substance is stored and a reaction unit that reacts with a hydrogen generation aqueous solution that reacts with the hydrogen reaction substance, and a liquid that stores the hydrogen generation aqueous solution. A storage section, a supply path for supplying the aqueous solution for hydrogen generation stored in the liquid storage section to the reaction section, and a discharge means for discharging hydrogen generated in the reaction section, and the pressure in the reaction section is The hydrogen generating facility is characterized in that an open / close means for opening and closing the flow path according to the pressure state is provided in the middle of the supply path while pressurizing the hydrogen generating aqueous solution in the liquid storage section.

  In the first aspect, hydrogen is generated by supplying an aqueous solution for hydrogen generation to the reaction section by the pressure of hydrogen generated in the reaction section without consuming electric power, and this hydrogen generation is connected to the discharge means. Since it is performed according to the consumption of hydrogen in the power generation unit of the fuel cell, a high energy density hydrogen generation facility can be provided.

  According to a second aspect of the present invention, the opening / closing means is provided on the downstream side of the pressure regulating valve which is opened when the pressure on the upstream side of the supply path is higher than a predetermined value, and on the downstream side of the pressure regulating valve. The hydrogen generation facility according to the first aspect has a check valve for preventing a back flow from the upstream side to the upstream side.

  In the second aspect, the pressure adjusting valve opens when the pressure in the reaction path is higher than the predetermined value, that is, when the pressure in the reaction section is higher than a predetermined value. When the pressure on the downstream side of the pressure regulating valve becomes higher than the pressure in the reaction part, the hydrogen generating aqueous solution is supplied into the reaction part.

  According to a third aspect of the present invention, the hydrogen generation facility according to the second aspect is characterized in that the pressure of a substance outside the hydrogen generation facility is used as a driving force as the closing force of the pressure regulating valve. It is in.

  In the third aspect, the pressure regulating valve can be driven using the pressure of the substance outside the hydrogen generation facility, for example, atmospheric pressure. For example, when the pressure inside the reaction unit is higher than atmospheric pressure, The regulating valve is opened.

  According to a fourth aspect of the present invention, the pressure regulating valve is a thin film or a thin plate that forms a flow path through which the hydrogen generating aqueous solution is passed and a part of a partition wall of the flow path and receives pressure to bend. A sealing member made of a flexible film, and a valve body that is fixed to the sealing member and moves in conjunction with the bending of the sealing member, and opens and closes the flow path by the movement to flow or block the hydrogen generating aqueous solution. And a connecting portion between the flow path and the supply path, and a structure in which a substance existing outside the hydrogen generation facility is in contact with the outside of the seal member. In the hydrogen generation facility.

  In the fourth aspect, when the internal pressure of the reaction part is higher than the stress applied to the valve body or the seal member in the direction in which the pressure adjustment valve is closed by a substance outside the hydrogen generation facility, the pressure adjustment valve is opened. Closes when is lower than atmospheric pressure.

  According to a fifth aspect of the present invention, the pressure regulating valve is provided so as to be movable outside the flexible tube through which the hydrogen generating aqueous solution passes, and the flexible tube is moved by the movement. The flexible part provided with the pressing part or the pressing part provided with a pressing part for crushing the inside or closing the inside, or a connecting part between the flexible tube and the supply path The hydrogen generation facility according to the third aspect is characterized in that a substance existing outside the hydrogen generation facility is in contact with the outside of the tube.

  In the fifth aspect, the pressure regulating valve is opened when the pressure inside the reaction part is higher than the stress applied to the pressing part in the direction in which the pressure regulating valve is closed by a substance outside the hydrogen generation facility, and the pressure inside the reaction part is atmospheric pressure. Closes when lower.

  According to a sixth aspect of the present invention, in addition to the pressure of the substance outside the hydrogen generation facility, the urging force of an elastic member is used as the valve closing force of the pressure regulating valve. The hydrogen generation facility according to any one of the aspects.

  In the sixth aspect, the system can be operated at an operating pressure equal to or higher than atmospheric pressure by using the biasing force of the elastic member in addition to the pressure of an external substance, for example, atmospheric pressure.

  According to a seventh aspect of the present invention, in any one of the second to sixth aspects, a temporary storage unit that temporarily stores the hydrogen generating aqueous solution is provided between the pressure regulating valve and the check valve. The hydrogen generation facility according to the aspect.

  In such a seventh aspect, the upstream side of the supply path of the pressure regulating valve, that is, the pressure regulating valve opens when the pressure in the reaction section is higher than a predetermined value, and the aqueous hydrogen generating solution when the upstream pressure is higher than the downstream side. Is supplied to the temporary storage part via the pressure regulating valve, and when the pressure in the temporary storage part becomes higher than the pressure in the reaction part, the aqueous solution for hydrogen generation is supplied into the reaction part.

  An eighth aspect of the present invention is the hydrogen according to the first aspect, wherein the opening / closing means has a pressure regulating valve that opens when the pressure on the downstream side of the supply path is lower than a predetermined value. In the generating facility.

  In the eighth aspect, the pressure regulating valve opens when the pressure of the reaction section is lower than the predetermined value, that is, when the pressure on the upstream side is higher than that on the downstream side. An aqueous solution for hydrogen generation is supplied into the reaction section downstream of the valve, that is, into the reaction section.

  According to a ninth aspect of the present invention, in the hydrogen generation facility according to the eighth aspect, the opening / closing means further includes a check valve for preventing a backflow from the downstream side to the upstream side.

  In the ninth aspect, backflow of hydrogen or an aqueous solution for hydrogen generation is prevented.

  The tenth aspect of the present invention is the hydrogen according to the eighth or ninth aspect, wherein the pressure of the substance inside the reaction section is used as the driving force as the closing force of the pressure regulating valve. In the generating facility.

  In the tenth aspect, the pressure regulating valve can be driven using the pressure of the substance inside the hydrogen generation facility, that is, the pressure of hydrogen. For example, when the pressure inside the reaction unit is lower than a predetermined value, The pressure adjustment valve is opened.

  In an eleventh aspect of the present invention, the pressure regulating valve is a thin film or a thin plate that forms a flow path through which the hydrogen generating aqueous solution passes and a part of a partition wall of the flow path and receives pressure to bend. A sealing member made of a flexible film, and a valve body that is fixed to the sealing member and moves in conjunction with the bending of the sealing member, and opens and closes the flow path by the movement to flow or block the hydrogen generating aqueous solution. And a connecting portion between the flow path and the supply path, and the substance existing inside the reaction section is in contact with the outside of the sealing member. Located in the hydrogen generation facility.

  In the eleventh aspect, the stress applied to the valve body and the seal member is lowered in the direction in which the pressure regulating valve is closed by the substance present in the reaction section, and the pressure on the upstream side of the flow path is relatively increased. The pressure regulating valve opens and closes when the internal pressure of the reaction section is higher than a predetermined value.

  According to a twelfth aspect of the present invention, the pressure regulating valve is provided so as to be movable outside the flexible tube through which the hydrogen generating aqueous solution passes, and the flexible tube is moved by the movement. The flexible part provided with the pressing part or the pressing part provided with a pressing part for crushing the inside or closing the inside, or a connecting part between the flexible tube and the supply path The hydrogen generation facility according to the tenth aspect is characterized in that the substance existing inside the reaction section is in contact with the outside of the tube.

  In the twelfth aspect, the stress applied to the valve body and the seal member is lowered in the direction in which the pressure regulating valve is closed by the substance present in the reaction section, and the pressure on the upstream side of the flow path is relatively increased. The pressure regulating valve opens and closes when the internal pressure of the reaction section is higher than a predetermined value.

  In a thirteenth aspect of the present invention, any one of the eighth to twelfth aspects, wherein a temporary storage unit that temporarily stores the aqueous solution for hydrogen generation is provided between the pressure regulating valve and the liquid storage unit. The hydrogen generation facility according to the aspect.

  In the thirteenth aspect, by using the biasing force of the elastic member in addition to the pressure of the internal substance, for example, the pressure of hydrogen, the system can be operated with a minimum operating pressure secured.

  In a fourteenth aspect of the present invention, the temporary storage unit has a structure in which an aqueous solution for hydrogen generation stored therein receives a predetermined pressure, and when the internal pressure of the reaction unit becomes smaller than the predetermined pressure. The hydrogen generation facility according to the seventh or thirteenth aspect is characterized in that an aqueous solution for hydrogen generation is supplied to the reaction section.

  In the fourteenth aspect, the supply of the hydrogen generating aqueous solution to the reaction unit can be set by a predetermined pressure received by the temporary storage unit.

  According to a fifteenth aspect of the present invention, the temporary storage portion is a movable wall in which at least a part of the wall is movable, and the movable wall is subjected to the predetermined pressure. The hydrogen generating facility according to the seventh or thirteenth aspect is characterized in that the movable wall moves and the volume of the temporary storage section changes.

  In the fifteenth aspect, the pressure supplied to the reaction unit can be set by the predetermined pressure received by the flexible wall.

  According to a sixteenth aspect of the present invention, there is provided a thin film or thin plate in which a part or the whole of the boundary wall between the temporary storage unit and the outside of the hydrogen generation facility can be bent by a pressure difference inside and outside the temporary storage unit. The hydrogen generating facility according to the seventh or thirteenth aspect is characterized in that the flexible membrane is subjected to pressure outside the hydrogen generating facility.

  In the sixteenth aspect, the pressure supplied to the reaction unit can be set by the predetermined pressure received by the flexible membrane.

  According to a seventeenth aspect of the present invention, in addition to the supply path, a bypass pipe that connects the temporary storage unit and the liquid storage unit is provided. In the hydrogen generation facility according to the embodiment.

  In the seventeenth aspect, the hydrogen generating aqueous solution is supplied to the temporary storage portion even at an internal pressure lower than the valve closing pressure of the pressure regulating valve.

  In an eighteenth aspect of the present invention, the bypass pipe is provided with a second check valve for preventing a backflow of the hydrogen generating aqueous solution from the temporary storage section to the liquid storage section. And the hydrogen generation facility according to the seventeenth aspect.

  In the eighteenth aspect, the backflow of the hydrogen generating aqueous solution through the bypass pipe is prevented by the second check valve.

  According to a nineteenth aspect of the present invention, any one of the first to eighteenth aspects is characterized in that the liquid storage part is composed of a container having a constant internal volume and has a through-hole capable of mass transfer in the upper part. The hydrogen generation facility according to the aspect.

  In the nineteenth aspect, the internal pressure of the reaction part is applied to the liquid storage part through the through hole.

  In a twentieth aspect of the present invention, any one of the first to eighteenth aspects is characterized in that the liquid storage part is composed of a container whose internal volume is variable according to the amount of the aqueous solution for hydrogen generation stored. In the hydrogen generation facility according to the embodiment.

  In the twentieth aspect, by providing a liquid storage section having a variable volume in the reaction section, the space in the reaction section when the hydrogen generating aqueous solution decreases can be expanded.

  According to a twenty-first aspect of the present invention, the container has a movable wall that can move at least a part of a wall that defines the outside, and the movable wall moves in accordance with a pressure difference between the inside and the outside, and The hydrogen generation facility according to the twentieth aspect, wherein the volume is variable.

  In the twenty-first aspect, the volume of the liquid storage unit changes due to the movable wall that moves according to the pressure difference.

  In a twenty-second aspect of the present invention, the container comprises a flexible wall made of a thin film or a thin plate, wherein a part or the whole of the wall defined from the outside can be bent by a pressure difference between the inside and the outside. And the hydrogen generation facility according to the twentieth aspect.

  In the twenty-second aspect, the volume of the liquid storage unit changes due to the bending of the flexible wall.

  A twenty-third aspect of the present invention is the hydrogen generation facility according to any one of the first to twenty-second aspects, wherein the hydrogen reaction substance contains a metal hydride that generates hydrogen by hydrolysis. .

  In this 23rd aspect, hydrogen produces | generates by reaction with the aqueous solution for hydrogen generation, and a metal hydride.

  In a twenty-fourth aspect of the present invention, the substance for hydrogen reaction includes the metal hydride, a solid organic acid or a salt thereof, a metal chloride, and platinum, gold, copper, nickel, iron, titanium, zirconium, And at least one selected from the group consisting of a metal composed of ruthenium and an alloy thereof, in the hydrogen generation facility according to the twenty-third aspect.

  In the twenty-fourth aspect, an additive is added to the metal hydride to promote the production of hydrogen.

  In a twenty-fifth aspect of the present invention, the hydrogen generating aqueous solution is mixed with water or at least one selected from the group consisting of an organic acid or a salt thereof, an inorganic acid or a salt thereof, and a metal chloride. The hydrogen generation facility according to the twenty-third or twenty-fourth aspect is characterized in that

  In the twenty-fifth aspect, hydrogen can be efficiently generated by using water or water mixed with an additive as the hydrogen generating aqueous solution.

  A twenty-sixth aspect of the present invention is characterized in that the hydrogen generating aqueous solution is an acid or base aqueous solution, and the hydrogen reaction substance is a metal. Located in the hydrogen generation facility.

  In the twenty-sixth aspect, hydrogen is generated by a reaction between an acid or base aqueous solution and a metal.

  According to a twenty-seventh aspect of the present invention, the hydrogen generation facility according to any one of the first to twenty-sixth aspects is provided as a fuel supply unit that supplies fuel to a negative electrode chamber of a power generation unit of a fuel cell. In the fuel cell system.

  In the twenty-seventh aspect, since the liquid solution for hydrogen generation can be sent by the pressure change in the reaction part due to the hydrogen generation reaction and the pressure drop due to the hydrogen consumption in the fuel cell, without using electric power. The liquid can be fed, and a high energy density fuel cell system can be provided.

  A twenty-eighth aspect of the present invention is a polymer solid fuel cell in which the power generation unit generates power by electrochemical reaction of hydrogen and oxygen, and the inside and the outside of the part from the fuel supply unit to the negative electrode chamber In the fuel cell system according to the twenty-seventh aspect, there is no movement of a substance.

  In the twenty-eighth aspect, there is provided a polymer solid fuel cell in which no substance moves inside and outside.

  The hydrogen generation facility of the present invention is to generate and supply necessary hydrogen by reacting an aqueous solution for hydrogen generation with a substance for hydrogen reaction.

  Here, as a combination of the hydrogen generation aqueous solution and the hydrogen reaction substance, water or an aqueous solution obtained by adding an additive to water is used as the hydrogen generation aqueous solution, and metal hydrogen that generates hydrogen by hydrolysis as the hydrogen reaction substance. Or a compound obtained by mixing an additive with this metal hydride.

  Such metal hydrides are alkali metal, alkaline earth metal, complex metal and hydrogen compounds, such as sodium hydride, sodium borohydride, sodium aluminum hydride, lithium aluminum hydride, lithium borohydride, hydrogenated Examples include lithium, calcium hydride, aluminum hydride, and magnesium hydride.

  In addition, as an additive to be mixed with a metal hydride, a solid organic acid or a salt thereof, a metal chloride, a metal composed of platinum, gold, copper, nickel, iron, titanium, zirconium, and ruthenium and alloys thereof And at least one selected from these may be used. As a result, the hydrogen generation reaction promoter and catalyst are mixed in the metal hydride, so that the reaction rate becomes extremely fast, and when the water is supplied to the metal hydride, the internal pressure of the reaction section can be immediately increased. It becomes like this.

  On the other hand, as an aqueous solution for hydrogen generation, it is preferable to use an aqueous solution obtained by mixing water with an organic acid or a salt thereof, an inorganic acid or a salt thereof, and a metal chloride in addition to water itself. As a result, an aqueous accelerator solution that promotes the hydrogen generation reaction can be obtained. Therefore, the reaction rate becomes extremely fast, and when the hydrogen generation reaction occurs, the internal pressure of the reaction part can be immediately increased.

  The substance added to such water is not particularly limited, and examples thereof include organic acids or salts thereof, inorganic acids or salts thereof, metal chlorides, etc. Examples of acids include sulfuric acid, malic acid, and citric acid. Examples of succinic acid and metal chlorides include cobalt chloride, iron chloride, nickel chloride, and platinum group chlorides.

  Further, as a combination of the hydrogen generating aqueous solution and the hydrogen reaction substance, there may be mentioned a case where the hydrogen generating aqueous solution uses an acid or base aqueous solution and the hydrogen reaction substance is a metal.

  Here, preferably, hydrochloric acid, sulfuric acid, or the like is used as an acid, and a base metal is used as a metal applied to these acids. On the other hand, examples of the base aqueous solution include a sodium hydroxide aqueous solution and a potassium hydroxide aqueous solution, and the metal applied to such a base aqueous solution is an amphoteric metal. By mixing these, hydrogen can be obtained at a high speed.

  As described above, according to the present invention, the hydrogen generating aqueous solution can be fed without using electric power or with low electric power. Thus, it is possible to provide a hydrogen supply facility and a fuel cell system with high energy density.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a configuration diagram of a fuel cell system of the present invention. The schematic configuration is a two-part configuration of a liquid-related unit that stores and sends an aqueous solution and a hydrogen-related unit that generates a hydrogen generation reaction and consumes the generated hydrogen for power generation. The fuel cell system has a structure in which there is no material exchange between the inside and the outside in principle.

  First, the liquid-related unit includes a liquid storage unit 11, a temporary storage unit 12, a supply pipe 15a that connects the liquid storage unit 11 and the temporary storage unit 12, a supply pipe 15b that is connected to the temporary storage unit 12 and is open at one end, The supply pipe 15a is provided with a pressure regulating valve 14, and the supply pipe 15b is provided with a check valve 13.

  A hydrogen generation aqueous solution 17 is stored in the liquid storage unit 11. The hydrogen generation aqueous solution 17 passes from the liquid storage unit 11 through the supply pipe 15 a, passes through the pressure regulating valve 14, and then reaches the temporary storage unit 12. Then, after passing through the supply pipe 15b from the temporary storage section 12 and passing through the check valve 13, it flows out from the open end of the supply pipe 15b. The check valve 13 is a normal tube check valve, and prevents a back flow from the open end of the supply pipe 15 b to the temporary storage unit 12.

  Next, the hydrogen-related unit includes a reaction unit 10, a negative electrode chamber 2, a power generation unit 1 of a polymer solid fuel cell, and a hydrogen conduit 3 that connects the reaction unit 10 and the negative electrode chamber 2. The reaction unit 10 functions as a gas chamber that is provided in communication with the negative electrode chamber 2 and stores hydrogen, which is a gas consumed in the negative electrode chamber 2.

  In the above equipment, the equipment excluding the power generation unit 1, the negative electrode chamber 2, and the hydrogen conduit 3 is the hydrogen generating equipment of the present invention, and shows a state in which the hydrogen discharging means of the hydrogen generating equipment is connected to the hydrogen conduit 3. . Therefore, hereinafter, the hydrogen generation facility itself will be described while explaining the entire fuel cell system including the hydrogen generation facility.

  The reaction unit 10 of the hydrogen generation facility is a part that stores the hydrogen reaction substance 16 and generates hydrogen. The negative electrode chamber 2 is a space for retaining hydrogen generated in the reaction unit 10 and sending hydrogen to the negative electrode of the power generation unit 1 of the polymer solid fuel cell. The power generation unit 1 of the polymer solid fuel cell is a part that generates electric power by electrochemically reacting hydrogen in the negative electrode chamber 2 and oxygen in the air.

  In the present embodiment, both units described above are arranged as follows. That is, the liquid storage unit 11 is disposed inside the reaction unit 10, the temporary storage unit 12 is installed outside the reaction unit 10, and the hydrogen generating aqueous solution 17 stored in the temporary storage unit 12 receives external pressure. did. However, the entire temporary storage unit 12 is not necessarily provided outside the reaction unit 10, and may be arranged so that at least a part of the wall of the temporary storage unit 12 is in contact with the outside of the reaction unit 10. Furthermore, the open end of the supply pipe 15b is arranged to open above the hydrogen reaction substance 16 inside the reaction section 10. In addition, although the liquid storage part 11, the pressure regulation valve 14, and the temporary storage part 12 are mentioned later in detail, the pressure regulation valve 14 is installed in the inside of the reaction part 10, and air | atmosphere for the opening / closing operation | movement of the pressure regulation valve 14 Therefore, as shown in FIG. 5, an air intake portion 38 is provided so that a part of the pressure regulating valve 14 is in contact with the air. By disposing each part as described above, the hydrogen generation aqueous solution 17 passes through the supply pipe 15b from the temporary storage part 12 and is supplied into the reaction part 10 from the open end of the supply pipe 15b.

  With such a configuration, when the pressure inside the reaction unit 10 becomes higher than the pressure outside the fuel cell system, the hydrogen generating aqueous solution 17 stored in the liquid storage unit 11 moves to the temporary storage unit 12, When the pressure inside the reaction unit 10 becomes lower than the pressure outside the fuel cell system, the hydrogen generating aqueous solution 17 in the temporary storage unit 12 moves to the liquid storage unit 11 until the pressure regulating valve 14 is closed. . Accordingly, since the hydrogen generation aqueous solution 17 can be fed by the pressure increase in the reaction part due to the hydrogen generation reaction and the pressure drop due to the hydrogen consumption in the fuel cell, the solution can be sent without using electric power. Is possible.

  According to the above structure, since the fuel cell system is a system in which the negative electrode chamber 2 is closed from the liquid storage unit 11 to the outside, the hydrogen generating aqueous solution 17 and the generated hydrogen remain inside. Therefore, the internal pressure increases due to the generation of hydrogen, and the internal pressure decreases due to hydrogen consumption due to the fuel cell reaction. Therefore, first, when a hydrogen generation reaction occurs in the reaction part, the internal pressure of the reaction part 10 and the negative electrode chamber 2 increases. As a result, pressure is applied to the liquid storage unit 11 and the hydrogen generation aqueous solution 17, so that when the pressure of the reaction unit 10 becomes higher than the pressure outside the fuel cell system, for example, atmospheric pressure, the hydrogen generation aqueous solution 17 is pressure-regulated. 14 to the temporary storage unit 12. At that time, although pressure is applied to the check valve 13 from the reaction unit 10 side, since the check valve 13 is closed, hydrogen does not flow into the temporary storage unit 12. Therefore, the internal pressure of the temporary storage unit 12 becomes the output pressure of the pressure adjustment valve 14.

  Next, when hydrogen is consumed by the power generation in the fuel cell, the internal pressure of the reaction unit 10 and the negative electrode chamber 2 decreases. Since the internal pressure of the liquid storage unit 11 is equal to the internal pressure of the reaction unit 10, when the internal pressure of the reaction unit 10 decreases, a pressure difference is generated between the temporary storage unit 12 and the liquid storage unit 11. The hydrogen generating aqueous solution 17 moves to the storage unit 11.

  However, when the internal pressure of the reaction unit 10 falls below the valve closing pressure of the pressure regulating valve 14, the pressure regulating valve 14 is closed, and the movement of the hydrogen generating aqueous solution 17 to the liquid storage unit 11 is stopped. The internal pressure of the temporary storage unit 12 at this time becomes the valve closing pressure of the pressure regulating valve 14. Further, when hydrogen is consumed by the fuel cell and the internal pressure of the reaction unit 10 and the negative electrode chamber 2 is lowered, the internal pressure of the reaction unit 10 becomes lower than the internal pressure of the temporary storage unit 12. The generation aqueous solution 17 moves to the reaction unit 10. As a result, the hydrogen reaction substance 16 stored in the reaction unit 10 and the hydrogen generation aqueous solution 17 come into contact with each other to cause a hydrogen generation reaction, and the internal pressures of the reaction unit 10 and the negative electrode chamber 2 rise again. Since hydrogen is consumed during operation of the fuel cell, this phenomenon occurs repeatedly, the hydrogen generating aqueous solution 17 moves to the reaction unit 10, and the volume of the hydrogen generating aqueous solution 17 in the liquid storage unit 11 decreases. At the same time, the space in the reaction unit 10, that is, the space for holding the reaction product and the residue increases. As a result, more hydrogen reaction substance 16 can be stored in the reaction unit 10 in consideration of the increase in space in the reaction unit 10.

  Furthermore, it is preferable that the temporary storage unit 12 receives the pressure of a substance existing outside the fuel cell system, and the volume of the temporary storage unit 12 is changed by the movement of the aqueous solution 17 for hydrogen generation. As a result, even when the valve closing pressure of the pressure regulating valve 14 is set to the pressure of a substance existing outside the fuel cell system, for example, equivalent to atmospheric pressure, if the internal pressure of the reaction unit 10 falls below atmospheric pressure, the atmospheric pressure is received. The aqueous solution 17 for hydrogen generation can be sent from the temporary storage unit 12 to the reaction unit while the volume of the temporary storage unit 12 is reduced. Therefore, the fuel cell system can be operated at atmospheric pressure, and as a result, the stress applied to the electrolyte membrane of the fuel cell can be reduced and the fuel cell system can be operated safely.

  Further, since the material pressure outside the fuel cell system is used as the driving force as the closing force of the pressure adjusting valve 14, the pressure adjusting valve 14 can be closed at a constant pressure regardless of the internal pressure of the reaction unit 10. Become.

  Here, the liquid storage unit 11 will be described. Specific examples of the liquid storage unit 11 and a part of the supply pipe 15a connected thereto are shown in FIGS. The site | part shown in the figure is provided in the reaction part 10 as above-mentioned.

  First, FIG. 2 is a configuration diagram illustrating a liquid storage unit 11A according to an example. 11 A of liquid storage parts are containers which have the opening part 20 in the upper part, The supply pipe | tube 15a is connected so that it may insert in this container, The edge part of the supply pipe | tube 15a extends to the bottom part of the liquid storage part 11 near. It is installed to be installed. With such a configuration, hydrogen generated in the reaction unit 10 flows into the liquid storage unit 11 through the opening 20 and can pressurize the liquid surface of the hydrogen generating aqueous solution 17. As a result, the hydrogen generation aqueous solution 17 flows out from the opening end of the supply pipe 15 b by an action described later, and is supplied to the reaction unit 10. Further, at this time, the liquid level of the hydrogen generating aqueous solution 17 decreases due to the hydrogen pressure, the space in the liquid storage unit 11 increases, and the space for holding the by-product generated in the reaction unit 10 increases.

  FIG. 3 is a perspective view of a liquid storage unit 11B having a structure different from that in FIG. The liquid storage unit 11B is a bag-like container composed of a flexible film, and a supply pipe 15a is attached so as to communicate with the inside of the bag-like container. With such a configuration, the hydrogen generation aqueous solution 17 flows out from the open end of the supply pipe 15b and is supplied to the reaction unit 10 to generate hydrogen, and the generated hydrogen pressurizes the outer surface of the liquid storage unit 11B, The flexible film is deformed so that the internal volume of the liquid storage unit 11B is reduced, and the internal hydrogen generation aqueous solution 17 is supplied from the supply pipe 15a. Further, as a result, the entire volume of the liquid storage unit 11B is reduced, and conversely, the space in the reaction unit 10 is increased.

  FIG. 4 is a side cross-sectional view of a liquid storage portion 11C different from FIGS. The liquid storage unit 11C is a fixed-shaped container, and the wall of one surface thereof is a movable wall 21. In this figure, the liquid storage part 11C is a cylindrical container such as a syringe, and a supply pipe 15a is attached to the bottom wall of the container end. The movable wall 21 is a plunger and is arranged at a position facing the bottom wall to which the supply pipe 15a is attached so that the hydrogen generating aqueous solution 17 is stored in a space between the movable wall 21 and the liquid storage unit 11. It has become. When the hydrogen generating aqueous solution 17 flows out from the open end of the supply pipe 15b and is supplied to the reaction unit 10, hydrogen is generated, and the movable wall 21 moves in a direction to reduce the volume of the liquid storage unit 11C by the hydrogen pressure. Further, along with this, the spatial volume of the reaction unit 10 increases.

  As described above, in the liquid storage units 11A to 11C, the hydrogen generation aqueous solution 17 incorporated therein is introduced into the supply pipe 15a due to an increase in the pressure in the reaction unit 10, and flows out from the open end of the supply pipe 15b. Therefore, the hydrogen generating aqueous solution 17 can be supplied without consuming electric power.

  In addition, when the hydrogen generating aqueous solution 17 is supplied to the reaction unit 10 in this way, the space volume of the reaction unit 10 increases, and there is also an effect that more bubbles and residues generated by the hydrogen generation reaction can be stored. It is. That is, even if the hydrogen generating aqueous solution 17 moves from the liquid storage unit 11 to the reaction unit 10, no dead space is generated, and hydrogen present in the liquid storage unit 11 when the hydrogen generating aqueous solution 17 moves to the reaction unit. The reduced volume of the aqueous solution for generation 17 can be used as a space for holding residues and reaction products, and more hydrogen reaction substance 16 can be stored in the reaction unit 10.

  Next, the pressure regulating valve will be described. FIGS. 5 and 6 show the pressure regulating valve 14, a part of the supply pipe 15 a that connects the pressure regulating valve 14 and the liquid storage unit 11, and a part of the supply pipe 15 b that connects to the temporary storage unit 12. Although the walls 35a and 35b of the reaction part housing are integral walls, FIGS. 5 and 6 are both cross-sectional views and are drawn separately because the part is open. Similarly, although the flow path plates 39a, 39b, and 39c are integral members, the flow paths 34a, 34b and the opening 33 are formed in the cross-sectional portion, and therefore, they are drawn separately in the drawing. Therefore, unless otherwise specified, the reaction unit casing wall 35 and the flow path plate 39 are described.

  First, FIG. 5 is a sectional view of a pressure regulating valve 14A according to an example. The pressure regulating valve 14A includes a flow path plate 39 in which flow paths 34a and 34b are formed and a valve body 30. The flow path 34a is connected to the supply pipe 15c connected to the liquid storage section 11, and the flow path 34b is connected to the supply pipe 15d connected to the temporary storage section 12. The flow path 34a and the flow path 34b communicate with each other through the opening 33, and the hydrogen generating aqueous solution 17 fed from the liquid storage section 11 passes through the flow path 34a, the opening 33, and the flow path 34b. As described above, the temporary storage unit 12 is supplied. The flow path plate 39 is fixed to the wall 35 of the reaction unit casing. In FIG. 5, the upper side of the reaction unit housing wall 35 is the outside of the fuel cell system, and the lower side is the inside of the reaction unit 10. Further, a part of the partition wall defining the flow path 34a is opened to the outside, and a seal member 31 made of a flexible member is attached to a part of the partition wall of the opening part to flow from the outside. The path 34a is partitioned. A valve body 30 fixed integrally with the seal member 31 is installed in the flow path 34a, and the opening 33 is opened and closed as the valve body 30 moves. Further, a spring 32 is provided to apply a load that urges the valve body 30 and the seal member 31 toward the opening 33.

  Here, in order to apply atmospheric pressure to the valve body 30 and the seal member 31, an air intake portion 38 is provided between the walls 35a and 35b of the reaction portion casing. Therefore, the atmospheric pressure outside the fuel cell system and the urging force of the spring 32 are applied to the seal member 31 from the upper surface, while the pressure of the hydrogen generating aqueous solution 17 is applied from the inside of the flow path 34. Yes. The seal member 31 is formed of a resin or rubber such as polyethylene, polypropylene, or silicone rubber, or a solid thin plate or thin film such as nickel, silicon, or ceramic. The body 30 can be moved. Since the load from the upper part of the seal member 31 when the opening 33 is closed is the atmospheric pressure and the urging force of the spring 32, it is constant. Therefore, the valve is opened only when the hydrogen generating aqueous solution 17 exceeds a predetermined pressure. Things are possible.

  In the case of the pressure regulating valve 14A in FIG. 5, when no stress is applied to the valve body 30 or the sealing member 31 in the closing direction, the pressure regulating valve 14A is opened when the internal pressure of the reaction unit 10 is higher than the atmospheric pressure. The valve is closed when the internal pressure of the reaction section is lower than atmospheric pressure.

  Specifically, when the internal pressure of the reaction unit 10 is higher than the atmospheric pressure, the pressure adjusting valve 14A is opened by the hydrogen generating aqueous solution 17 that moves from the liquid storage unit 11 in response to the internal pressure of the reaction unit 10, and the temporary storage unit 12 An aqueous solution 17 for hydrogen generation is fed. On the other hand, when the internal pressure of the reaction unit 10 decreases, the hydrogen generating aqueous solution 17 continues to open the pressure regulating valve 14A due to the internal pressure of the reaction unit 10 when the internal pressure of the reaction unit 10 is higher than atmospheric pressure. However, when the internal pressure of the reaction unit 10 decreases from the atmospheric pressure, the pressure on the valve body 30 due to the atmospheric pressure becomes larger than the weight applied by the hydrogen generating aqueous solution 17, so the pressure regulating valve 14 </ b> A is closed.

  FIG. 6 is a cross-sectional view of a pressure regulating valve 14B different from FIG. A resin tube 37 made of a flexible member is installed in the pressure regulating valve 14B, and a flow path plate 39 is installed below the wall 35 of the reaction unit casing. In FIG. 6, the upper side of the reaction unit housing wall 35 is the outside of the fuel cell system, and the lower side is the inside of the reaction unit 10. The resin tube 37 is connected to a supply pipe 15 c connected to the liquid storage unit 11 and a supply pipe 15 d connected to the temporary storage unit 12, so that the hydrogen generation aqueous solution 17 is supplied. Also, an atmospheric air intake 38 is provided on a part of the wall 35 of the reaction part casing so that a part of the resin tube 37 is in contact with the outside of the fuel cell system, and a part of the flexible partition wall of the resin tube 37 is large. Under atmospheric pressure. In addition, a pressing portion 36 that compresses in the cross-sectional radial direction of the resin tube 37 is installed in a state of being urged in the compression direction by a spring 32. Therefore, when the pressure of the aqueous solution 17 for hydrogen generation inside the resin tube 37 falls below a predetermined value, the pressing portion 36 moves downward to crush the resin tube 37 and block the circulation of the aqueous solution 17 for hydrogen generation. It has become.

  The pressure regulating valve 14B in FIG. 6 operates in the same manner as the pressure regulating valve 14A in FIG. 5, and when the internal pressure of the reaction unit 10 is higher than the atmospheric pressure applied to the pressing unit 36 in the closing direction, the pressure regulating valve 14B is opened. When the internal pressure of the reaction unit 10 is lower than the atmospheric pressure, the valve is closed.

  Next, the structure of the temporary storage unit 12 will be described. FIG. 7 is a cross-sectional view of the temporary storage unit 12. A supply pipe 15 is connected to the temporary storage unit 12 in order to allow the hydrogen generation aqueous solution 17 to flow into or out of the temporary storage unit 12. This supply pipe 15 was installed inside the wall 35 of the reaction section casing. In FIG. 7, the upper side of the reaction unit housing wall 35 is the outside of the fuel cell system, and the lower side is the inside of the reaction unit 10.

  The temporary storage section 12 has a wall on one side of the partition wall as a free wall 40 made of a flexible member, and is arranged in an opening 41 provided in the wall 35 of the reaction section casing so as to be in contact with the outside of the fuel cell system. The atmospheric pressure is applied to the free wall 40 from above (outside), and the pressure of the hydrogen generating aqueous solution 17 is applied from below (inside). The free wall 40 is formed of a resin or rubber such as polyethylene, polypropylene, or silicone rubber, or a solid thin plate or thin film such as nickel, silicon, or ceramic. The volume of the temporary storage unit 12 is variable.

(Example)
Now, using the structure described above, the fuel cell system of FIG. 1 was manufactured and operated. As parts, the structure of FIG. 3 was used for the liquid storage part 11 and the structure of FIG. The materials used were stainless steel for the reaction section housing and supply pipe 15, polypropylene for the liquid storage section 11, silicone rubber for the resin tube 37 of the pressure regulating valve 14, and silicone for the free wall 40 of the temporary storage section 12. A sheet was used. The reaction unit 10 is a rectangular container with an internal volume of 90 cc, the liquid storage unit 11 has an internal volume of 40 cc, the supply pipe 15 has an inner diameter of 4 mm, the resin tube has an inner diameter of 2 mm, the free wall 40 has a thickness of 0.5 mm, The volume of the temporary storage part was 2 cc.

  Further, the spring 32 of the pressure regulating valve 14B is adjusted so that the pressure from the upper portion of the pressing portion 36 by the atmospheric pressure and the force of the spring 32 is 10 kPa, and the reaction portion 10 is closed when the internal pressure is 10 kPa (gauge pressure). .

  Further, an aqueous malic acid solution was stored in the liquid storage unit 11 as the hydrogen generation aqueous solution 17, and sodium borohydride powder was held in the reaction unit 10 as the hydrogen reaction material 16.

  Next, the operation of the produced fuel cell system will be described with reference to FIG.

  When the power generation unit 1 is connected to a load, hydrogen in the fuel cell system and oxygen in the air cause a fuel cell reaction to generate electric power. Since power generation proceeds while consuming hydrogen, the internal pressure of the negative electrode chamber 2, the hydrogen conduit 3, and the reaction unit 10 decreases. Here, since the temporary storage unit 12 receives atmospheric pressure, when the internal pressure falls below atmospheric pressure, a differential pressure is generated between the temporary storage unit 12 and the reaction unit 10, and the malic acid aqueous solution stored in the temporary storage unit 12 Move to reaction section 10. The sodium borohydride stored in the reaction unit 10 causes a hydrogen generation reaction by contacting with the malic acid aqueous solution. The generated hydrogen passes through the hydrogen conduit 3 and is supplied to the negative electrode chamber 2.

  When the internal pressure of the reaction unit 10, the hydrogen conduit 3, and the negative electrode chamber 2 rises from the atmospheric pressure due to the generation of hydrogen, first, the internal pressure of the reaction unit 10 becomes higher than the temporary storage unit 12, so that hydrogen tries to flow back through the supply pipe 15b. To do. However, since the check valve 13 is installed on the supply pipe 15b, backflow can be prevented.

  On the other hand, the liquid storage unit 11 is compressed by receiving the internal pressure of the reaction unit 10, and the malic acid aqueous solution stored therein moves to the pressure regulating valve 14 through the supply pipe 15a. The pressure regulating valve 14 receives the pressure of the malic acid aqueous solution in the valve opening direction and 10 kPa (gauge pressure) in the valve closing direction. When the internal pressure of the reaction unit 10 exceeds 10 kPa (gauge pressure), the force in the valve opening direction increases due to the pressure of the malic acid aqueous solution, the pressure regulating valve 14 opens, and the malic acid aqueous solution is supplied to the temporary storage unit 12.

  Thereafter, when the hydrogen generation rate decreases and the hydrogen consumption rate in the power generation unit 1 exceeds, the internal pressures of the negative electrode chamber 2, the hydrogen conduit 3, and the reaction unit 10 begin to decrease. Since the pressure regulating valve 14 is open while the internal pressure is higher than 10 kPa (gauge pressure), the malic acid aqueous solution flows backward from the temporary storage unit 12 to the liquid storage unit 11. However, when the internal pressure falls below 10 kPa (gauge pressure), the pressure regulating valve 14 is closed. The internal pressure of the temporary storage unit 12 at this time is 10 kPa (gauge pressure). When the internal pressure of the reaction unit 10 further decreases, a pressure difference occurs between the temporary storage unit 12 and the reaction unit 10, the check valve 13 opens, the malic acid aqueous solution is supplied to the sodium borohydride, and the internal pressure is increased again. Will rise.

  An experimental result in this structure is shown in FIG. FIG. 8 is a graph showing a situation during operation of the fuel cell system according to the present invention. In order from the top, (a) the open / close state of the pressure regulating valve, (b) the presence or absence of liquid supply to the reaction part of the aqueous solution for hydrogen generation, and (c) the change over time in the internal pressure are shown. The horizontal axis of the graph represents elapsed time, the vertical axis represents (a) opening / closing of the pressure regulating valve, (b) liquid feeding or liquid feeding stop, and (c) gauge pressure in the reaction unit 10.

  In general, the internal pressure of the reaction part 10 according to (c) repeatedly increased rapidly due to the generation of hydrogen and decreased due to power consumption due to power generation. Initially, the operation was performed near atmospheric pressure, but after 20 minutes or more from the start, the upper pressure limit was 25 kPa (gauge pressure), the lower pressure limit was 5 kPa (gauge pressure), and an almost stable profile was obtained. It was. In other words, it was possible to operate the fuel cell by generating hydrogen using pressure fluctuations in the system without using any electric power.

  This phenomenon will be described in association with (a) and (b). Since the initial pressure is atmospheric pressure and is lower than 10 kPa (gauge pressure) which is the valve opening pressure of the pressure adjusting valve 14, the pressure adjusting valve 14 is closed as shown in (a). Therefore, the malic acid aqueous solution is sent to the reaction unit 10 as shown in (b) from the pressure difference between the internal pressure of the temporary storage unit 12 and the internal pressure of the reaction unit 10. When the internal pressure of the reaction unit 10 starts to rise, the internal pressure of the reaction unit 10 becomes higher than that of the temporary storage unit 12, so that the check valve 13 operates and the feeding of the malic acid aqueous solution stops. Further, when the pressure exceeds 10 kPa (gauge pressure), the pressure regulating valve 14 is opened, and the malic acid aqueous solution moves from the liquid storage unit 11 to the temporary storage unit 12. This is repeated because hydrogen is constantly being consumed.

  Although continuous operation could be continued even after a long operation, the reaction rate decreased and a phenomenon was observed in which no stable pressure increase was observed. Even at high pressure, the pressure does not exceed 10 kPa (gauge pressure), the pressure regulating valve 14 does not open, and the malic acid aqueous solution may not be sent from the liquid storage unit 11 to the temporary storage unit 12.

(Other examples)
An example of a fuel cell system as another embodiment for avoiding the phenomenon of the embodiment described above is shown in FIG.

  FIG. 9 is a configuration diagram of a fuel cell system in which a bypass pipe 19 is added to the fuel cell system of FIG. The bypass pipe 19 is a pipe that connects the liquid storage section 11 and the temporary storage section 12 separately from the supply pipe 15, and a check valve 18 is installed therebetween. The check valve 18 prevents the backflow of the hydrogen generating aqueous solution 17 from the temporary storage unit 12 to the liquid storage unit 11.

  By providing the bypass pipe 19 in this manner, even when the internal pressure of the reaction unit 10 does not exceed the gauge pressure, the aqueous hydrogen generating solution 17 is moved from the liquid storage unit 11 to the temporary storage unit 12 due to the pressure difference when the pressure is higher than the atmospheric pressure. I was able to do it.

  The requirements for hydrogen supply and hydrogen storage in the fuel cell system are to supply hydrogen at a rate commensurate with the generated current, to generate hydrogen at low power, preferably without consuming power, and hydrogen reaction. The storage material 16 and the hydrogen generation aqueous solution 17 are stored at a high ratio with respect to the entire volume, and the reaction product resulting from the hydrogen generation reaction is not allowed to flow out to the power generation unit 1 side. In particular, if the hydrogen reaction substance 16 and the hydrogen generation aqueous solution 17 can be stored at a high ratio with respect to the entire volume, the hydrogen storage amount can be increased and the energy density can be improved.

  However, conventionally, the hydrogen reaction substance 16 and the hydrogen generation aqueous solution 17 could not be stored at a high ratio with respect to the entire volume. The reason is that the reaction product by the hydrogen generation reaction is formed in a foam shape, expands in volume, and flows out to the power generation unit 1 side.

  In the fuel cell system of the present embodiment, the volume of the reaction unit 10 is 90 cc, and the liquid storage unit 11 having a volume of 40 cc is provided therein. As a result of the operation, the volume of the liquid storage unit 11 decreased with the progress of the reaction, and the space in the reaction unit 10 increased. Therefore, even if about 8 g of sodium borohydride was added, the reaction product did not flow out of the reaction part 10.

(Comparative example)
The configuration of the conventional fuel cell system is a separate container in which the reaction unit 10 and the liquid storage unit 11 are separated, and the reaction unit 10 must be made small. Therefore, there is a space for storing the reaction product in the reaction unit 10. It was small and caused the reaction product to flow out at an early stage.

  When the fuel cell system of the comparative example is manufactured in accordance with the fuel cell system of Example 1, the volume of the reaction unit 10 is 46 cc, and the liquid storage unit 11 having a volume of 40 cc is provided separately from this.

  As a result of the operation, the weight of sodium borohydride stored in the reaction unit 10 was at most about 4 g, and the reaction product overflowed from the reaction unit 10.

(Other embodiments)
Further, FIG. 10 shows another embodiment of the fuel cell system of the present invention. In addition, the same code | symbol is attached | subjected to the same member as the member shown in FIG.

  In addition, although embodiment mentioned above was an example which employ | adopted the pressure regulating valve which opens when the pressure of the upstream of a supply path is higher than predetermined value as an opening-and-closing means provided in the supply path, in this embodiment, As the opening / closing means, a pressure regulating valve that is opened when the pressure on the downstream side of the supply path is lower than a predetermined value is employed.

  The liquid-related unit of the fuel cell system of FIG. 10 is connected to the liquid storage unit 11, the temporary storage unit 12, the supply pipe 15a connecting the liquid storage unit 11 and the temporary storage unit 12, and the temporary storage unit 12, and one end is open. The supply pipe 15b, the supply pipe 15a further includes a check valve 23, and the supply pipe 15b includes a pressure adjustment valve 24.

  A hydrogen generation aqueous solution 17 is stored in the liquid storage unit 11. The hydrogen generation aqueous solution 17 passes from the liquid storage unit 11 through the supply pipe 15 a, passes through the check valve 23, and then reaches the temporary storage unit 12. Then, after passing through the supply pipe 15b from the temporary storage section 12 and passing through the pressure regulating valve 24, it flows out from the open end of the supply pipe 15b. The check valve 23 is a normal tube check valve and prevents a back flow from the temporary storage unit 12 to the liquid storage unit 11.

  Next, the hydrogen-related unit includes a reaction unit 10, a negative electrode chamber 2, a power generation unit 1 of a polymer solid fuel cell, and a hydrogen conduit 3 that connects the reaction unit 10 and the negative electrode chamber 2. The reaction unit 10 functions as a gas chamber that is provided in communication with the negative electrode chamber 2 and stores hydrogen, which is a gas consumed in the negative electrode chamber 2.

  In the above equipment, the equipment excluding the power generation unit 1, the negative electrode chamber 2, and the hydrogen conduit 3 is the hydrogen generating equipment of the present invention, and shows a state in which the hydrogen discharging means of the hydrogen generating equipment is connected to the hydrogen conduit 3. .

  The reaction unit 10 of the hydrogen generation facility is a part that stores the hydrogen reaction substance 16 and generates hydrogen. The negative electrode chamber 2 is a space for retaining hydrogen generated in the reaction unit 10 and sending hydrogen to the negative electrode of the power generation unit 1 of the polymer solid fuel cell. The power generation unit 1 of the polymer solid fuel cell is a part that generates electric power by electrochemically reacting hydrogen in the negative electrode chamber 2 and oxygen in the air.

  Here, as the liquid storage part 11, the thing of the structure demonstrated in FIG. 2 thru | or FIG. 4 can be employ | adopted, and the thing of FIG.

  Further, the pressure regulating valve 24 opens so that the hydrogen generating aqueous solution 17 from the temporary storage unit 12 side can flow through the supply pipe 15b when the internal pressure of the reaction unit 10 becomes a predetermined pressure or less. To do. The internal pressure of the temporary storage unit 12 is higher than the pressure at which the pressure adjusting valve 24 is opened by being pressurized by the supplied hydrogen generating aqueous solution 17 (pressure exceeding the predetermined pressure value of the reaction unit 10 for opening the pressure adjusting valve 24). ) And the hydrogen generation aqueous solution 17 is sent to the reaction unit 10 from the supply pipe 15b due to the internal pressure difference between the temporary storage unit 12 and the reaction unit 10. As a result, the hydrogen generation aqueous solution 17 and the hydrogen reaction substance 16 stored in the reaction unit 10 come into contact with each other to cause a hydrogen generation reaction in the reaction unit 10.

  In the fuel cell system having such a pressure regulating valve 24, when the power generation unit 1 is connected to a load, hydrogen inside the negative electrode chamber 2 and oxygen in the air cause a fuel cell reaction to generate electric power. Since power generation proceeds while consuming hydrogen, the internal pressure of the negative electrode chamber 2, the hydrogen conduit 3, and the reaction unit 10 decreases. Here, since the temporary storage unit 12 receives atmospheric pressure, when the internal pressure is lower than the atmospheric pressure, a differential pressure is generated between the temporary storage unit 12 and the reaction unit 10, and hydrogen generation stored in the temporary storage unit 12 is generated. The aqueous solution 17 (for example, malic acid aqueous solution) moves to the reaction unit 10 through the supply pipe 15b.

  When the hydrogen generation aqueous solution 17 moves to the reaction section 10, it contacts with the hydrogen reaction substance 16 (for example, sodium borohydride) to cause a hydrogen generation reaction. The generated hydrogen passes through the hydrogen conduit 3 and is supplied to the negative electrode chamber 2. Due to the generation of hydrogen, the internal pressure of the reaction unit 10, the hydrogen conduit 3, and the negative electrode chamber 2 rises from the atmospheric pressure, and the internal pressure of the reaction unit 10 becomes higher than that of the temporary storage unit 12. For this reason, although hydrogen tries to flow backward through the supply pipe 15b, the pressure regulating valve 24 prevents the reverse flow.

  On the other hand, the hydrogen generating aqueous solution 17 in the liquid storage unit 11 is pressurized by receiving the internal pressure of the reaction unit 10, and the hydrogen generating aqueous solution 17 stored in the liquid storage unit 11 is supplied from the supply pipe 15a to the check valve. 23 and supplied to the temporary storage unit 12.

  Thereafter, when the hydrogen generation rate decreases and the hydrogen consumption rate in the power generation unit 1 exceeds, the internal pressures of the negative electrode chamber 2, the hydrogen conduit 3, and the reaction unit 10 begin to decrease. When the internal pressure decreases and a pressure difference is generated between the temporary storage unit 12 and the reaction unit 10, the pressure regulating valve 24 is opened and the hydrogen generation aqueous solution 17 flows from the temporary storage unit 12 into the reaction unit 10. As a result, the hydrogen generation aqueous solution 17 comes into contact with the hydrogen reaction substance 16 to cause a hydrogen generation reaction, and the internal pressure of the reaction unit 10 increases again.

  By repeating the above, hydrogen is generated, and hydrogen as fuel is supplied to the negative electrode chamber 2 of the fuel cell.

  When the volume of the liquid storage unit 11 decreases as the hydrogen generating aqueous solution 17 is supplied from the liquid storage unit 11 to the reaction unit 10, the volume of the reaction unit 10 increases accordingly, so that the dead space is reduced. Thus, the area where hydrogen is generated in a small space can be increased, and the space can be saved without reducing the amount of hydrogen generated. In addition, the amount of hydrogen generation can be increased without increasing the space.

  The fuel cell system described above can be a fuel cell system including a hydrogen generation facility that can generate a sufficient amount of hydrogen in a small volume.

  In addition, the structure demonstrated in FIG.5 and FIG.6 is employable as the specific structure of the pressure regulation valve 24 used by this embodiment.

  When the pressure regulating valve 14A shown in FIG. 5 is used as the pressure regulating valve 24, the upper part of the reaction part housing wall 35 is the inside of the reaction part 10, the lower part is the outside of the fuel cell system, and the atmosphere intake part 38 is used. What is necessary is just to make it apply the pressure inside the reaction part 10 to a place. As a result, the pressure inside the reaction unit 10 and the biasing force of the spring 32 are applied to the seal member 31 from the upper surface, while the pressure of the hydrogen generating aqueous solution 17 is applied from the inside of the flow path 34. Yes. Therefore, it is possible to open the valve only when the internal pressure of the reaction unit 10 decreases and the hydrogen generating aqueous solution 17 relatively exceeds. By providing the spring 32, even if the internal pressure in the reaction unit 10 is extremely low, the valve does not open unless the pressure of the aqueous solution 17 for hydrogen generation is greater than the urging force of the spring 32. Is not necessarily provided.

  The same applies to the case where the pressure adjustment valve 14B of FIG. 6 is used as the pressure adjustment valve 24. In FIG. 6, the upper part of the reaction part housing wall 35 is the inside of the reaction part 10, and the lower part is the outside of the fuel cell system. A part of the 37 flexible partition walls may receive the internal pressure of the reaction unit 10. Thereby, when the internal pressure of the reaction part 10 becomes high and the pressure of the aqueous solution 17 for hydrogen generation inside the resin tube 37 is relatively lower, the pressing part 36 moves downward to crush the resin tube 37, The flow of the aqueous solution for generation 17 is blocked, and conversely, when the internal pressure of the reaction unit 10 increases, the valve is opened.

  In the embodiment of FIG. 10, the check valve 23 is provided on the upstream side of the temporary storage unit 12, but may be provided on the downstream side, or the check valve 23 may be omitted.

  INDUSTRIAL APPLICABILITY The present invention can be used, for example, in the industrial field of a hydrogen generation facility that decomposes metal hydrides to generate hydrogen and a fuel cell system that uses hydrogen generated in the hydrogen generation facility as fuel.

It is a block diagram of the fuel cell system by this invention. It is a block diagram which shows an example of a liquid storage part. It is a perspective view which shows an example of a liquid storage part. It is side surface sectional drawing which shows an example of a liquid storage part. It is sectional drawing which shows an example of a pressure regulating valve. It is sectional drawing which shows an example of a pressure regulating valve. It is sectional drawing which shows an example of a temporary storage part. It is a graph which shows the following situations at the time of operation of a fuel cell system by the present invention. (A) Opening / closing state of pressure regulating valve (b) Presence / absence of liquid supply to hydrogenation aqueous solution (c) Change in internal pressure of fuel cell system over time It is a block diagram of the fuel cell system which added the bypass pipe to FIG. It is a block diagram of the fuel cell system which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric power generation part 2 Negative electrode chamber 3 Hydrogen conduit | pipe 10 Reaction part 11, 11A, 11B, 11C Liquid storage part 12 Temporary storage part 13 Check valve 14, 14A, 14B Pressure regulation valve 15, 15a, 15b, 15c, 15d Supply pipe 16 Hydrogen reaction substance 17 Hydrogen generation aqueous solution 18 Check valve 19 Bypass pipe 20 Opening 21 Moving wall 30 Valve body 31 Seal member 32 Spring 33 Opening 34, 34a, 34b Flow path 35, 35a, 35b Wall 36 Pressing part 37 Resin tube 38 Atmospheric intake part 39, 39a, 39b, 39c Flow path plate 40 Free wall arrow Indicates the liquid feeding direction of the check valve

Claims (28)

  A reaction part for storing a hydrogen reaction substance and reacting with the hydrogen generation aqueous solution reacting with the hydrogen reaction substance, a liquid storage part for storing the hydrogen generation aqueous solution, and a hydrogen generation stored in the liquid storage part A supply passage for supplying the aqueous solution to the reaction unit, and a discharge means for discharging the hydrogen generated in the reaction unit, so that the pressure in the reaction unit pressurizes the aqueous solution for hydrogen generation in the liquid storage unit. And an opening / closing means for opening and closing the flow path depending on the pressure state is provided in the middle of the supply path.   The opening / closing means is provided on a downstream side of the pressure regulating valve that is opened when a pressure on the upstream side of the supply path is higher than a predetermined value, and prevents a back flow from the downstream side to the upstream side. The hydrogen generation facility according to claim 1, further comprising a check valve.   3. The hydrogen generation facility according to claim 2, wherein a pressure of a substance outside the hydrogen generation facility is used as a driving force as a closing force of the pressure regulating valve. The pressure regulating valve,
A flow path for passing the aqueous solution for hydrogen generation;
A seal member formed of a flexible film which is a thin film or a thin plate which forms a part of the partition wall of the flow path and receives a pressure to bend;
A valve body that is fixed to the seal member and moves in conjunction with the deflection of the seal member, and opens and closes the flow path by the movement to flow or shut off the hydrogen generating aqueous solution;
A connecting portion between the flow path and the supply path;
The hydrogen generation facility according to claim 3, wherein a substance existing outside the hydrogen generation facility is in contact with an outside of the seal member. The pressure regulating valve,
A flexible tube for passing the hydrogen generating aqueous solution;
A pressing part that is movably provided outside the flexible tube and crushes the flexible tube by the movement to close the inside or to be in a circulation state;
A connecting portion between the flexible tube and the supply path;
The hydrogen generation facility according to claim 3, wherein a substance existing outside the hydrogen generation facility is in contact with an outer side of the pressing portion or the flexible tube provided with the pressing portion.   The hydrogen generation facility according to any one of claims 3 to 5, wherein, as a closing force of the pressure regulating valve, an urging force by an elastic member is used in addition to a pressure of a substance outside the hydrogen generation facility. .   The hydrogen generation facility according to any one of claims 2 to 6, wherein a temporary storage section for temporarily storing the aqueous solution for hydrogen generation is provided between the pressure regulating valve and the check valve.   2. The hydrogen generation facility according to claim 1, wherein the opening / closing means has a pressure regulating valve that opens when the pressure on the downstream side of the supply path is lower than a predetermined value.   9. The hydrogen generation facility according to claim 8, wherein the opening / closing means further includes a check valve for preventing a reverse flow from the downstream side to the upstream side.   The hydrogen generation facility according to claim 8 or 9, wherein the pressure of the substance inside the reaction unit is used as a driving force as a closing force of the pressure regulating valve. The pressure regulating valve,
A flow path for passing the aqueous solution for hydrogen generation;
A seal member formed of a flexible film which is a thin film or a thin plate which forms a part of the partition wall of the flow path and receives a pressure to bend;
A valve body that is fixed to the seal member and moves in conjunction with the deflection of the seal member, and opens and closes the flow path by the movement to flow or shut off the hydrogen generating aqueous solution;
A connecting portion between the flow path and the supply path;
The hydrogen generation facility according to claim 10, wherein a substance existing inside the reaction portion is in contact with an outside of the seal member. The pressure regulating valve,
A flexible tube for passing the hydrogen generating aqueous solution;
A pressing part that is movably provided outside the flexible tube and crushes the flexible tube by the movement to close the inside or to be in a circulation state;
A connecting portion between the flexible tube and the supply path;
11. The hydrogen generation facility according to claim 10, wherein a substance present inside the reaction unit is in contact with an outer side of the pressing unit or the flexible tube provided with the pressing unit.   The hydrogen generation facility according to claim 8, wherein a temporary storage unit that temporarily stores the aqueous solution for hydrogen generation is provided between the pressure control valve and the liquid storage unit.   The temporary storage unit has a structure in which an aqueous solution for hydrogen generation stored therein receives a predetermined pressure, and when the internal pressure of the reaction unit becomes smaller than the predetermined pressure, the aqueous solution for hydrogen generation is supplied to the reaction unit. The hydrogen generation facility according to claim 7 or 13, wherein the hydrogen generation facility is supplied.   The temporary storage portion is a movable wall in which at least a part of the wall is movable and the movable wall receives the predetermined pressure, and the movement of the hydrogen generating aqueous solution causes the movable wall to move. The hydrogen generation facility according to claim 7 or 13, wherein the volume of the temporary storage section changes.   A part or the whole of the boundary wall between the temporary storage unit and the outside of the hydrogen generation facility is a flexible film made of a thin film or a thin plate that can be bent by a pressure difference between the inside and the outside of the temporary storage unit, The hydrogen generation facility according to claim 7 or 13, wherein the flexible membrane is subjected to pressure outside the hydrogen generation facility.   The hydrogen generation facility according to any one of claims 7 and 13 to 16, wherein a bypass pipe that connects the temporary storage unit and the liquid storage unit is provided separately from the supply path.   18. The hydrogen generation according to claim 17, wherein the bypass pipe is provided with a second check valve for preventing a backflow of the hydrogen generating aqueous solution from the temporary storage unit to the liquid storage unit. Facility.   The hydrogen generation facility according to any one of claims 1 to 18, wherein the liquid storage part is composed of a container having a constant internal volume, and has a through-hole capable of mass transfer at an upper part thereof.   The hydrogen generation facility according to any one of claims 1 to 18, wherein the liquid storage unit includes a container whose internal volume is variable according to the amount of the aqueous solution for hydrogen generation stored therein.   The container has a movable wall that can move at least a part of a wall that defines the outside, and the movable wall moves according to a pressure difference between the inside and the outside to vary the volume of the container. The hydrogen generation facility according to claim 20.   21. The hydrogen generation according to claim 20, wherein a part or the whole of the wall defined by the outside is a flexible wall made of a thin film or a thin plate that can be bent by a pressure difference between the inside and the outside. Facility.   The hydrogen generation facility according to any one of claims 1 to 22, wherein the substance for hydrogen reaction includes a metal hydride that generates hydrogen by hydrolysis.   The metal for hydrogen reaction includes the metal hydride, a solid organic acid or a salt thereof, a metal chloride, a metal composed of platinum, gold, copper, nickel, iron, titanium, zirconium, and ruthenium, and alloys thereof. 24. The hydrogen generation facility according to claim 23, wherein at least one selected from the group consisting of:   The hydrogen generating aqueous solution is water or water mixed with at least one selected from the group consisting of an organic acid or a salt thereof, an inorganic acid or a salt thereof, and a metal chloride. The hydrogen generation facility according to claim 23 or 24.   The hydrogen generation facility according to any one of claims 1 to 22, wherein the hydrogen generation aqueous solution is an acid or base aqueous solution, and the hydrogen reaction substance is a metal.   27. A fuel cell system comprising the hydrogen generation facility according to claim 1 as a fuel supply unit that supplies fuel to a negative electrode chamber of a power generation unit of a fuel cell. The power generation unit is a polymer solid fuel cell that generates electricity by electrochemical reaction of hydrogen and oxygen,
28. The fuel cell system according to claim 27, wherein no substance moves between the inside and the outside of a portion from the fuel supply section to the negative electrode chamber.

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