JP2010189233A - Hydrogen generating system and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen generating system capable of shortening time required for restarting hydrogen generation, and a fuel cell system. <P>SOLUTION: The hydrogen generating system is equipped with: a hydrogen generating material container 1 for containing a hydrogen generating material 10 that generates hydrogen by reacting with water; a liquid supplying part 11 that supplies water or an aqueous alkali solution to the hydrogen generating material 10 contained in the hydrogen generating material container 1; and a liquid selection judging part 8 that judges which liquid, i.e. water or the aqueous alkali solution, should be supplied to the hydrogen generating material 10. The liquid selection judging part 8 monitors the status of hydrogen generation inside the hydrogen generating material container 1 and judges the type of the liquid that should be subsequently supplied to the hydrogen generating material 10 according to the hydrogen generation interruption time, i.e. the time that has elapsed since the termination of hydrogen generation carried out by previous liquid supply. The liquid supplying part 11 supplies the type of liquid judged by the liquid selection judging part 8 to the hydrogen generating material 10 contained in the hydrogen generating material container 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hydrogen generation system and a fuel cell system, and more particularly, to a hydrogen generation system and a fuel cell system using a hydrogen generation material that generates hydrogen by reaction with water.

  In recent years, with the widespread use of cordless devices such as personal computers and mobile phones, secondary batteries as power sources are increasingly required to be smaller and have higher capacities. Currently, lithium ion secondary batteries have been put into practical use as secondary batteries that have high energy density and can be reduced in size and weight, and demand for portable power sources is increasing. However, this lithium secondary battery has a problem that a sufficient continuous use time cannot be guaranteed for some cordless devices.

  Under such circumstances, a polymer electrolyte fuel cell has been studied as an example of a battery that can meet the above demand. Solid polymer fuel cells that use a solid polymer electrolyte as the electrolyte, oxygen in the air as the positive electrode active material, and fuel (hydrogen, methanol, etc.) as the negative electrode active material are expected to have higher energy density than lithium ion secondary batteries It is attracting attention as a battery system that can be used. The fuel cell can be used continuously as long as fuel and oxygen are supplied.

  There are several candidates for the fuel used in the fuel cell, but each has various problems, and a final decision has not yet been made. A direct methanol fuel cell that uses methanol as the fuel and reacts directly with the electrode is easy to miniaturize and is expected as a portable power source in the future, but has a problem of voltage drop due to methanol crossover, The expected energy density is not obtained. Here, the crossover of methanol is a phenomenon in which methanol supplied to the negative electrode (fuel electrode) passes through the electrolyte membrane and reaches the positive electrode (air electrode).

  On the other hand, when hydrogen is used as a fuel, for example, a method of supplying hydrogen stored in a high-pressure tank or a hydrogen storage alloy tank has been put into practical use, but the volume and weight are increased, and the energy density is reduced. Therefore, it is not suitable as a portable power source. There is also a method in which a hydrocarbon-based fuel is used as the fuel and hydrogen is extracted by reforming it. However, since a reformer is required and problems such as heat supply and heat insulation to the reformer occur, it is still unsuitable as a portable power source.

  Under such circumstances, a method has been proposed in which hydrogen is generated by a chemical reaction at a low temperature of 100 ° C. or lower and used as a fuel. In these methods, for example, a metal that reacts with water such as aluminum, magnesium, silicon, and zinc to generate hydrogen is used as a hydrogen source (Patent Documents 1 to 6).

  According to the method described in Patent Documents 1 to 3 in which aluminum is reacted with an alkali or an acid, hydrogen is easily generated chemically, but it is necessary to add an equivalent amount of alkali or acid corresponding to aluminum, and a hydrogen source. There arises a problem of a decrease in energy density due to an increase in the ratio of other materials. In addition, there is a problem that the oxide or hydroxide as a reaction product forms a film on the surface of the metal, the inner metal cannot contact with water, and the oxidation reaction stops only on the surface of the metal. Prone to occur. For this reason, Patent Document 3 proposes a hydrogen generating material in which the proportion of aluminum is 85% by weight or less.

  On the other hand, in Patent Document 4 which attempts to avoid the above problem by mechanically removing the surface film, there is a problem that the apparatus becomes large, for example, mechanical equipment for removing the surface film is required. In Patent Document 5, alumina is added as a catalyst for making it difficult to form the hydroxide film, and hydrogen is generated at a low temperature of 50 ° C. However, aluminum alone does not generate hydrogen, and it is necessary to add a certain amount of catalyst, so that there is a problem that the aluminum content decreases.

  As a technique for solving these problems, in Patent Document 6, hydrogen is easily generated at a low temperature by using a hydrogen generating material containing at least one metal material selected from the group consisting of aluminum, magnesium, and alloys thereof. A hydrogen production apparatus and a fuel cell that can be generated are disclosed.

US Pat. No. 6,506,360 Japanese Patent No. 2566248 JP 2004-231466 A JP 2001-31401 A JP-T-2004-505879 JP 2006-306700 A

  However, in the case of Patent Document 6, since the oxide covers the surface of the hydrogen generating material as the time for generating hydrogen from the hydrogen generating material elapses, the start-up time required for generating hydrogen first and the previous time When compared with the restart time required to generate hydrogen again after a period of time after hydrogen generation stopped, there was a problem that the restart time became longer.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a hydrogen generation system and a fuel cell system that can shorten the restart time.

  A first hydrogen generation system according to the present invention includes a hydrogen generation system that generates hydrogen using a hydrogen generation material that generates hydrogen by reaction with water, a hydrogen generation material storage container that stores the hydrogen generation material, water Or the liquid supply part which supplies alkaline aqueous solution to the said hydrogen generating material in the said hydrogen generating material storage container, and the liquid which determines which liquid should be supplied to the said hydrogen generating material among water and alkaline aqueous solution And a selection determination unit, wherein the liquid selection determination unit monitors the state of hydrogen generation in the hydrogen generating material storage container, and is an elapsed time since the generation of hydrogen by the previous liquid supply stopped. Based on the hydrogen generation stop time, the type of liquid to be supplied next to the hydrogen generating material is determined, and the liquid supply unit determines the type of liquid determined by the liquid selection determination unit. The and supplying to the hydrogen generating material of the hydrogen generating material storage container.

  A second hydrogen generation system of the present invention is a hydrogen generation system that generates hydrogen using a hydrogen generation material that generates hydrogen by reaction with water, a hydrogen generation material storage container that stores the hydrogen generation material, water Or the liquid supply part which supplies alkaline aqueous solution to the said hydrogen generating material in the said hydrogen generating material storage container, and the liquid which determines which liquid should be supplied to the said hydrogen generating material among water and alkaline aqueous solution A selection / determination unit; and a temperature detector that detects a temperature in the hydrogen generating material storage container, wherein the liquid selection determination unit determines a temperature in the hydrogen generation material storage container detected by the temperature detector. The type of liquid to be supplied to the hydrogen generating material next is monitored based on the temperature in the hydrogen generating material storage container when the supply of liquid to the hydrogen generating material is started. Constant, and the liquid supply unit, and supplying the type of liquid which is determined by the liquid selection determining unit to the hydrogen generating material of the hydrogen generating material storage container.

  A third hydrogen generation system according to the present invention is a hydrogen generation system that generates hydrogen using a hydrogen generation material that generates hydrogen by reaction with water, a hydrogen generation material storage container that stores the hydrogen generation material, water Or the liquid supply part which supplies alkaline aqueous solution to the said hydrogen generating material in the said hydrogen generating material storage container, and the liquid which determines which liquid should be supplied to the said hydrogen generating material among water and alkaline aqueous solution A selection determination unit; and a temperature detector that detects a temperature in the hydrogen generation material storage container, wherein the liquid selection determination unit is a state of hydrogen generation in the hydrogen generation material storage container, and the temperature detection When the hydrogen generation is stopped, which is the elapsed time since the generation of hydrogen by the previous liquid supply stopped And the type of liquid to be supplied to the hydrogen generating material next is determined based on the temperature in the hydrogen generating material storage container when liquid supply to the hydrogen generating material is started, and the liquid supply unit The type of liquid determined by the liquid selection determining unit is supplied to the hydrogen generating material in the hydrogen generating material storage container.

  A first fuel cell system of the present invention supplies hydrogen generated from the hydrogen generation system of the present invention to a fuel cell.

  A second fuel cell system according to the present invention is a fuel cell system including a fuel cell using hydrogen as a fuel, a hydrogen generating material storage container for storing a hydrogen generating material that generates hydrogen by reaction with water, and water or an alkali. A liquid supply unit that supplies an aqueous solution to the hydrogen generating material in the hydrogen generating material storage container, and a liquid selection determination that determines which liquid of water and an alkaline aqueous solution should be supplied to the hydrogen generating material And a hydrogen supply unit that supplies hydrogen generated in the hydrogen generating material storage container to the fuel cell, wherein the liquid selection determination unit monitors the power generation state of the fuel cell and supplies the previous liquid supply Next, supply to the hydrogen generating material based on a power generation stop time, which is an elapsed time after the power generation of the fuel cell using hydrogen generated as a fuel is stopped To kind of liquid is determined, the liquid supply unit, and supplying the type of liquid which is determined by the liquid selection determining unit to the hydrogen generating material of the hydrogen generating material storage container.

  According to the present invention, since the liquid selected from the alkaline aqueous solution and water is supplied to the hydrogen generating material based on the hydrogen generation stop time or the temperature in the hydrogen generating material storage container, hydrogen is generated again. Therefore, it is possible to provide a highly reliable hydrogen generation system and fuel cell system that require a short restart time.

1 is a schematic configuration diagram of a hydrogen generation system according to Embodiment 1 of the present invention. It is a schematic block diagram of the hydrogen generation system which concerns on Embodiment 2 of this invention. It is a schematic block diagram of the hydrogen generation system which concerns on Embodiment 3 of this invention. It is a schematic block diagram of the hydrogen generation system which concerns on Embodiment 4 of this invention. It is a schematic block diagram of the hydrogen generation system which concerns on Embodiment 5 of this invention. It is a schematic block diagram of the fuel cell system which concerns on Embodiment 7 of this invention. It is a flowchart for demonstrating the liquid selection determination process by the liquid selection determination part 8 in Embodiment 1 of this invention. It is a flowchart for demonstrating the liquid selection determination process by the liquid selection determination part 8a in Embodiment 3 of this invention. It is a flowchart for demonstrating the liquid selection determination process by the liquid selection determination part 8b in Embodiment 5 of this invention.

  Hereinafter, the hydrogen generation system and the fuel cell system of the present invention will be specifically described with reference to the drawings. However, the present invention is not limited thereto.

(Embodiment 1)
First, the hydrogen generation system according to Embodiment 1 of the present invention will be described. FIG. 1 is a diagram illustrating a schematic configuration of the hydrogen generation system according to the first embodiment.

  In FIG. 1, the hydrogen generation system of Embodiment 1 includes a hydrogen generating material container 1, a liquid selection valve 2, an alkaline aqueous solution tank 3, a water tank 4, a liquid selection valve control unit 5, a liquid selection determination unit 8, and a liquid supply. Unit 11 and hydrogen discharge unit 12.

  The hydrogen generating material storage container 1 stores a hydrogen generating material 10 that generates hydrogen by a reaction with water. The material and shape of the hydrogen generating material container 1 are not particularly limited as long as the hydrogen generating material 10 can be stored. However, the material and shape from which liquid and hydrogen do not leak from other than the liquid supply unit 11 and the hydrogen discharge unit 12. Is preferred. As a specific material of the container, a material that does not easily allow liquid and hydrogen to permeate and does not break even when heated to about 120 ° C. is preferable. For example, a metal such as aluminum or iron, or a resin such as polyethylene or polypropylene may be used. Can be used. Further, as the shape of the container, a prismatic shape, a cylindrical shape or the like can be adopted.

  The hydrogen generating material 10 stored in the hydrogen generating material storage container 1 may be any material that generates hydrogen by reaction with water. For example, at least one metal material selected from the group consisting of aluminum, magnesium, and alloys thereof can be used. This metal material and water react to generate hydrogen. In particular, it is preferable that the metal material contains 80% by mass or more of particles having a particle size of 60 μm or less because the reactivity with water is improved.

  Furthermore, the hydrogen generating material 10 preferably includes a heat generating material that generates heat by reacting with water at room temperature. When the hydrogen generating material 10 includes a heat generating material, the heat generating material reacts with water to generate heat even when the water supplied into the hydrogen generating material storage container 1 is at a low temperature. Hydrogen generation reaction is promoted, and hydrogen can be generated quickly. Moreover, it is preferable that the ratio of a metal material is more than 85 mass% and 99 mass% or less in the total mass of a metal material and a heat-generating material. This is because if the amount of the metal material is too small, the amount of hydrogen generation decreases, and if the amount of the heat generating material is too large, the temperature increases so that it becomes difficult to control the hydrogen generation reaction.

  As the heat generating material contained in the hydrogen generating material 10, for example, at least one compound selected from the group consisting of calcium oxide, magnesium oxide, calcium chloride, magnesium chloride and calcium sulfate can be used.

  When the metal material contained in the hydrogen generating material 10 is an aluminum alloy or a magnesium alloy, in order to generate hydrogen more efficiently, the aluminum alloy or the magnesium alloy may contain 2 to 20% by mass of an additive element. preferable. As the additive element, for example, at least one element selected from the group consisting of silicon, iron, copper, manganese, magnesium, zinc, nickel, titanium, lead, tin, and chromium can be used.

  By the way, since a stable oxide film is generally formed on the surface of a metal material, it hardly reacts with water at room temperature, and the reaction with water may not proceed even when heated. However, if the average particle size is 100 μm or less, the action of suppressing the reaction with water by the oxide film is reduced and it is difficult to react with water at room temperature, but if heated, the reaction with water is promoted and the hydrogen generation reaction is sustained. To come. When the average particle size of the metal material is 30 μm or less, the reaction with water is further promoted, and hydrogen can be generated more efficiently. On the other hand, if the particle size of the metal material is reduced, the hydrogen generation rate can be increased. However, if the particle size is smaller than 0.1 μm, not only the flammability is increased and handling becomes difficult, but also the packing density of the metal material is lowered. As a result, the energy density tends to decrease. Therefore, the particle size of the metal material is preferably 0.1 μm or more.

  In addition, the average particle diameter of a metal material means the value of the particle diameter in the volume-based integrated fraction 50%. As a method for measuring the average particle diameter, for example, a laser diffraction / scattering method or the like can be used. Specifically, this is a particle diameter distribution measurement method using a scattering intensity distribution detected by irradiating a measurement target substance dispersed in a liquid phase such as water with laser light. As a particle size distribution measuring apparatus using a laser diffraction / scattering method, for example, “Microtrac HRA (product name)” manufactured by Nikkiso Co., Ltd. can be used.

  Moreover, the metal material can use the powder-form thing produced by the atomizing method. In order to generate hydrogen more efficiently, the metal material is preferably subjected to a surface treatment for improving the reactivity with water on the surface by chemical means or mechanical means. The surface treatment of the metal material is performed, for example, by mechanically stirring the metal material in a solvent. Moreover, the metal material may be formed in the shape of a pellet or a granule.

  The liquid selection valve 2 selects either an alkaline aqueous solution stored in the alkaline aqueous solution tank 3 or water stored in the water tank 4.

  The liquid selection valve control unit 5 controls the liquid selection valve 2 according to the determination result of the liquid selection determination unit 8.

  The liquid selection determination unit 8 determines which liquid should be supplied to the hydrogen generating material 10 among water and an alkaline aqueous solution. The liquid selection determination unit 8 includes a timer 6 and a hydrogen generation stop time calculation unit 7, monitors the hydrogen generation state in the hydrogen generating material storage container 1, and stops the generation of hydrogen due to the previous liquid supply. The type of liquid to be supplied to the hydrogen generating material 10 next is determined based on the hydrogen generation stop time that is an elapsed time since then.

  Here, the stop of hydrogen generation means a state in which the reaction between the hydrogen generating material 10 and the liquid has stopped, but in practice, a state in which the detected hydrogen generation amount is equal to or less than a predetermined value set in advance. It can be determined that hydrogen generation has stopped. The predetermined value is set in consideration of the hydrogen detection method and system in the system. In this case, the liquid selection determination unit 8 starts counting by the timer 6 when detecting that the hydrogen generation amount is equal to or less than a predetermined value.

  As a specific method for detecting the stoppage of hydrogen generation, for example, the hydrogen discharged from the hydrogen discharge unit 12 is actually supplied to the negative electrode of the fuel cell to operate the fuel cell, and the voltage value of the fuel cell A method for determining the stoppage of hydrogen generation based on the above. Further, the hydrogen generation amount may be evaluated by a mass flow meter or the like, and it may be determined that the hydrogen generation is stopped when the hydrogen generation amount is smaller than a predetermined hydrogen generation amount. Furthermore, both determination by operating the fuel cell and determination using the mass flow meter may be used in combination.

  The liquid supply unit 11 supplies water or an alkaline aqueous solution to the hydrogen generating material 10 in the hydrogen generating material storage container 1. The liquid supply unit 11 is connected to the liquid selection valve 2 and supplies the liquid selected by the liquid selection valve 2. Note that the amount of liquid per unit time supplied by the liquid supply unit 11 is not always constant. The liquid supply unit 11 can change the liquid supply amount per unit time according to the hydrogen generation amount required for the hydrogen generation system of the first embodiment from a portion not shown. Since it is such a form, the liquid supply part 11 may supply a liquid continuously or may supply intermittently.

  The hydrogen discharger 12 discharges the hydrogen generated from the hydrogen generating material 10 to the outside in the hydrogen generating material storage container 1.

  Next, the operation of the hydrogen generation system according to the first embodiment will be described. First, the hydrogen generating material storage container 1 stores the hydrogen generating material 10, and the liquid is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen. When hydrogen is generated, the amount of liquid supplied from the liquid supply unit 11 is controlled in accordance with the amount of hydrogen being generated and the amount of hydrogen generated required by the hydrogen generation system of the first embodiment from a portion not shown.

  Next, a method for determining the type of liquid supplied from the liquid supply unit 11 to the hydrogen generating material 10 in the hydrogen generating material storage container 1 in Embodiment 1 will be described in detail with reference to FIG. Explained. FIG. 7 is a flowchart illustrating the liquid selection determination process performed by the liquid selection determination unit 8 according to the first embodiment.

  When the liquid selection determination process by the liquid selection determination unit 8 is started (step S101), first, a hydrogen generation stop time t_stop, which is an elapsed time since the generation of hydrogen by the previous liquid supply stopped, is set to the timer 6 and the hydrogen generation. Calculation is performed using the stop time calculation unit 7 (step S102). Then, the calculated hydrogen generation stop time t_stop is compared with a preset time t_stop_1 (step S103). Usually, t_stop_1 is set within a range of 30 minutes to 50 minutes. As a result of the comparison, when the hydrogen generation stop time t_stop is within the set time t_stop_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water stored in the water tank 4 (step S105). If the hydrogen generation stop time t_stop is longer than the set time t_stop_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is an alkaline aqueous solution stored in the alkaline aqueous solution tank 3 (step S104).

  Here, the reason why two types of water and aqueous alkali solution are used as the liquid supplied to the hydrogen generating material 10 will be described. When the elapsed time since the generation of hydrogen from the hydrogen generating material 10 by the previous liquid supply has stopped is short, the temperature in the hydrogen generating material storage container 1 is high, so that it is not an alkaline aqueous solution that increases the hydrogen generation rate. Even if water is supplied to the hydrogen generating material 10, the restart time required for generating hydrogen again does not become remarkably long. Therefore, when the relationship t_stop ≦ t_stop_1 is satisfied, water and the hydrogen generating material 10 From this, hydrogen was generated. On the other hand, if the elapsed time after the generation of hydrogen from the hydrogen generating material 10 by the previous liquid supply stops increases, the degree of formation of an oxide film on the surface of the hydrogen generating material 10 increases, so hydrogen is generated again. Therefore, when the relationship t_stop_1 <t_stop is satisfied, hydrogen is generated from the aqueous alkali solution having a hydrogen generation rate higher than that of water and the hydrogen generating material 10. It was. The reason why the hydrogen generation rate is higher when the hydrogen generating material 10 is reacted with the aqueous alkali solution than when the hydrogen generating material 10 is reacted with water is that the aqueous alkaline solution removes the oxide film formed on the surface of the hydrogen generating material 10.

  The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10 (step S106). Thereafter, the process from step S105 to step S107 is repeated until an instruction to terminate hydrogen generation is received from the part not shown in FIG. 1 (step S107). That is, even if the relationship of t_stop_1 <t_stop is satisfied in step S103 and the process proceeds to step S104 and an alkaline aqueous solution is selected, once hydrogen is generated from the hydrogen generating material 10 (step S106), Until the user receives an instruction to end generation of hydrogen (step S107), the process returns to step S105 to select water and supply water to the hydrogen generating material 10 to generate hydrogen. In step S106, it is confirmed that hydrogen is generated from the hydrogen generating material 10. As a method for confirming that hydrogen is generated, the hydrogen discharged from the hydrogen discharge unit 12 is actually supplied to the negative electrode of the fuel cell to operate the fuel cell, and based on the voltage value of the fuel cell. Can be determined.

  When an instruction to end hydrogen generation is received in step S107, the process proceeds to step S108, the operation of the hydrogen generation system is stopped, and t_stop is reset by substituting zero for the hydrogen generation stop time t_stop. Then, the process returns to step S102, and the hydrogen generation stop time t_stop is counted until the next liquid supply is started.

  As described above, according to the hydrogen generation system of the first embodiment, the hydrogen generation stop time t_stop, which is the elapsed time after the generation of hydrogen from the hydrogen generation material 10 by the previous liquid supply stops, is calculated and calculated. When t_stop is compared with a preset set time t_stop_1 and the relationship t_stop ≦ t_stop_1 is satisfied, the water stored in the water tank 4 is supplied to the hydrogen generating material 10 and the relationship t_stop_1 <t_stop is satisfied. In this case, since the alkaline aqueous solution stored in the alkaline aqueous solution tank 3 is supplied to the hydrogen generating material 10, if the elapsed time since the generation of hydrogen by the previous liquid supply stopped is long, the hydrogen generating material Since the temperature in the container 1 is low and the reaction rate of the hydrogen generation reaction is thought to be slow, By reacting the large alkaline aqueous solution and a hydrogen generating material 10 on the remote hydrogen generation rate can be shortened restart time required to generate the hydrogen again.

(Embodiment 2)
Hereinafter, the hydrogen generation system according to Embodiment 2 of the present invention will be described. The difference from the first embodiment is that two types of alkaline aqueous solutions having different pH values are used as the alkaline aqueous solution supplied to the hydrogen generating material 10.

  FIG. 2 is a diagram illustrating a schematic configuration of the hydrogen generation system according to the second embodiment. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

  The alkaline aqueous solution tank 3a stores a strong alkaline aqueous solution having a pH value x that satisfies the relationship 7 <y <x, and the alkaline aqueous solution tank 3b stores a weak alkaline aqueous solution having a pH value y. Here, x is usually in the range of pH 10 to pH 14.

  The overall operation of the hydrogen generation system according to the second embodiment is the same as that of the hydrogen generation system according to the first embodiment. Since the liquid selection determination method is different from that of the first embodiment, the liquid selection determination method according to the second embodiment will be described below with reference to FIG.

  When the liquid selection determination process by the liquid selection determination unit 8 is started, first, a timer 6 and a hydrogen generation stop time calculation unit are used as a hydrogen generation stop time t_stop which is an elapsed time since the generation of hydrogen by the previous liquid supply stopped. 7 is used for calculation. Then, the calculated hydrogen generation stop time t_stop is compared with the first set time t_stop_1 and the second set time t_stop_2 that are set in advance so as to satisfy t_stop_1 <t_stop_2. Normally, t_stop_1 is set within a range of 20 minutes to 35 minutes, and t_stop_2 is set within a range of 35 minutes to 50 minutes. As a result of the comparison, if the hydrogen generation stop time t_stop is within the first set time t_stop_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water contained in the water tank 4. When the hydrogen generation stop time t_stop is longer than the first set time t_stop_1 and within the second set time t_stop_2, the liquid to be supplied to the hydrogen generating material 10 next is weak alkali contained in the alkaline aqueous solution tank 3b. Determined to be an aqueous solution. When the hydrogen generation stop time t_stop is longer than the second set time t_stop_2, it is determined that the next liquid to be supplied to the hydrogen generating material 10 is a strong alkaline aqueous solution stored in the alkaline aqueous solution tank 3a.

  Here, the reason why two types of alkaline aqueous solutions having different pH values are used will be described. Utilizing the fact that the alkaline aqueous solution having a large pH value removes the oxide film on the surface of the hydrogen generating material 10 is larger than the alkaline aqueous solution having a small pH value, and as the t_stop becomes longer, Since the degree of formation of an oxide film on the surface is increased, hydrogen is generated from the strong alkali aqueous solution having a high hydrogen generation rate and the hydrogen generating material 10 when the relationship t_stop_2 <t_stop is satisfied. When the relationship t_stop_1 <t_stop ≦ t_stop_2 is satisfied, the oxide film can be removed even with a weak alkaline aqueous solution having a hydrogen generation rate lower than that of the strong alkaline aqueous solution. It was decided to generate hydrogen.

  The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10. Once hydrogen is generated from the hydrogen generating material 10, water is supplied to the hydrogen generating material 10 to generate hydrogen until an instruction from the user not to end hydrogen generation is received from a portion not shown. When an instruction to end hydrogen generation is received from the user, t_stop is reset and the hydrogen generation stop time t_stop is counted until the next liquid supply is started.

  As described above, according to the hydrogen generation system of the second embodiment, the hydrogen generation stop time t_stop, which is the elapsed time since the generation of hydrogen from the hydrogen generation material 10 by the previous liquid supply stopped, is calculated and calculated. When t_stop is compared with the first set time t_stop_1 and the second set time t_stop_2 set in advance satisfying t_stop_1 <t_stop_2, and if the relationship t_stop ≦ t_stop_1 is satisfied, the water stored in the water tank 4 is When the hydrogen generation material 10 is supplied and the relationship t_stop_1 <t_stop ≦ t_stop_2 is satisfied, the weak alkaline aqueous solution stored in the alkaline aqueous solution tank 3b is supplied to the hydrogen generation material 10 and the relationship t_stop_2 <t_stop is satisfied. If the alkaline water Since the strong alkaline aqueous solution stored in the liquid tank 3 a is supplied to the hydrogen generating material 10, the process after the hydrogen generation from the hydrogen generating material 10 by the previous liquid supply to the hydrogen generating material 10 is stopped. When the time is long, the temperature in the hydrogen generating material container 1 is low, and the reaction rate of the hydrogen generating reaction is considered to be slow. Therefore, depending on the length of the hydrogen generation stop time, a weak alkaline aqueous solution or a strong alkaline aqueous solution is used. By reacting with the hydrogen generating material 10, the restart time required to generate hydrogen again can be shortened.

(Embodiment 3)
Hereinafter, the hydrogen generation system according to Embodiment 3 of the present invention will be described. The difference from Embodiments 1 and 2 is that the type of liquid to be supplied to the hydrogen generating material 10 is determined based on the temperature in the hydrogen generating material storage container 1.

  FIG. 3 is a diagram illustrating a schematic configuration of the hydrogen generation system according to the third embodiment. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The temperature detector 13 detects the temperature in the hydrogen generating material storage container 1. The liquid selection determination unit 8a determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material 10. The liquid selection determination unit 8a monitors the temperature in the hydrogen generating material storage container 1 detected by the temperature detector 13 and starts the liquid supply to the hydrogen generating material 10 in the hydrogen generating material storage container 1. Based on the temperature, the type of liquid to be supplied to the hydrogen generating material 10 next is determined.

  The overall operation of the hydrogen generation system according to the third embodiment is the same as that of the hydrogen generation system according to the first and second embodiments. Since the liquid selection determination method is different from the hydrogen generation systems of the first and second embodiments, the liquid selection determination method according to the third embodiment will be described below in detail with reference to FIG. FIG. 8 is a flowchart showing the liquid selection determination process by the liquid selection determination unit 8a in the third embodiment.

  When the liquid selection determination process by the liquid selection determination unit 8a is started (step S201), first, the temperature T in the hydrogen generating material container 1 is detected by the temperature detector 13 (step S202). Then, the detected temperature T is compared with a preset set temperature T_1 (step S203). Usually, T_1 is set within a range of 35 ° C to 50 ° C. As a result of the comparison, when the detected temperature T is equal to or higher than the set temperature T_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water stored in the water tank 4 (step S205). When the detected temperature T is lower than the set temperature T # 1, it is determined that the next liquid to be supplied to the hydrogen generating material 10 is an alkaline aqueous solution stored in the alkaline aqueous solution tank 3 (step S204).

  Here, the reason for determining the type of liquid supplied to the hydrogen generating material 10 based on the temperature in the hydrogen generating material storage container 1 will be described. When the temperature T in the hydrogen generating material storage container 1 is high, the reaction rate of the hydrogen generating reaction increases. Therefore, even if water is supplied to the hydrogen generating material 10 instead of the alkaline aqueous solution that increases the hydrogen generating rate, Since the restart time required for generating the hydrogen does not become remarkably long, hydrogen is generated from water and the hydrogen generating material 10 when the relationship T_1 ≦ T is satisfied. On the other hand, when the temperature T in the hydrogen generating material storage container 1 is low, the reaction rate of the hydrogen generating reaction is reduced. Therefore, depending on the surface state of the hydrogen generating material 10, the restart time required to generate hydrogen again becomes significant. Therefore, when the relationship of T <T_1 is satisfied, hydrogen is generated from the aqueous alkali solution having a higher hydrogen generation rate than water and the hydrogen generating material 10.

  The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10 (step S206). Thereafter, the processes in steps S202 to S206 are repeated until the user receives an instruction to end hydrogen generation from a portion not shown in FIG. When the user receives an instruction to end hydrogen generation, the process ends.

  As described above, according to the hydrogen generation system of the third embodiment, the temperature T in the hydrogen generating material storage container 1 when the liquid supply to the hydrogen generating material 10 is started is detected, and the detected temperature T is set in advance. When the relationship T_1 ≦ T is satisfied with respect to the temperature T_1, water stored in the water tank 4 is supplied to the hydrogen generating material 10, and when the relationship T <T_1 is satisfied, the alkaline aqueous solution tank 3 When the temperature in the hydrogen generating material container 1 is low, the aqueous alkali solution and the hydrogen generating material 10 having a higher hydrogen generation rate than water are used. By reacting, it is possible to shorten the restart time required for generating hydrogen again.

  In the hydrogen generation system according to the third embodiment, hydrogen is once generated from an alkaline aqueous solution having a hydrogen generation rate larger than that of water and the hydrogen generation material 10, and the temperature T in the hydrogen generation material container 1 is set in advance. When the temperature becomes equal to or higher than T_1, that is, when the relationship of T_1 ≦ T is satisfied, water is generated from water and the hydrogen generating material 10 by switching to water having a hydrogen generation rate lower than that of the alkaline aqueous solution. As a result, the amount of alkaline aqueous solution required for system operation can be reduced. Thereby, the start-up time of the hydrogen generation system can be shortened and the amount of the alkaline aqueous solution used can be reduced.

  By the way, the effect of simply reacting water and the hydrogen generating material 10 without using the hydrogen generation system of the third embodiment and the effect of using the hydrogen generation system of the third embodiment are as follows. Street. As the hydrogen generating material 10, hydrogen is generated using a material in which 86% by mass of aluminum particles containing 90% by mass or more of aluminum particles having a particle size of 60 μm or less and 14% by mass of calcium oxide as a heat generating material are mixed. The temperature in the hydrogen generating material container 1 after 10 minutes from the time when the generation of hydrogen was stopped was 50 ° C. When water was supplied in this state, the restart time required to generate hydrogen again was 2 minutes. On the other hand, hydrogen was generated using the same hydrogen generating material 10, and the temperature in the hydrogen generating material storage container 1 30 minutes after the hydrogen generation stopped was 30 ° C. When water was supplied in this state, the restart time required to generate hydrogen again was 5 minutes. In contrast to the comparative example described above, in the hydrogen generation system according to the third embodiment, when T_1 is set to 45 ° C., the temperature in the hydrogen generating material storage container 1 after 30 minutes from when hydrogen generation stops is the above-described temperature. As described above, since the temperature is 30 ° C., the aqueous alkali solution and the hydrogen generating material 10 are reacted. When the aqueous alkali solution and the hydrogen generating material 10 were actually reacted, the restart time required to generate hydrogen again was 2 minutes, which is compared with the case where the hydrogen generating system of Embodiment 3 was not used. As a result, a remarkable effect of shortening the restart time was obtained.

(Embodiment 4)
Hereinafter, the hydrogen generation system according to Embodiment 4 of the present invention will be described. The difference from Embodiment 3 is that two types of alkaline aqueous solutions having different pH values are used as the alkaline aqueous solution supplied to the hydrogen generating material 10.

  FIG. 4 is a diagram illustrating a schematic configuration of the hydrogen generation system according to the fourth embodiment. 4, the same components as those in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted.

  The alkaline aqueous solution tank 3a stores a strong alkaline aqueous solution having a pH value x that satisfies the relationship 7 <y <x, and the alkaline aqueous solution tank 3b stores a weak alkaline aqueous solution having a pH value y. Here, x is usually in the range of pH 10 to pH14.

  Hereinafter, the operation of the entire hydrogen generation system according to the fourth embodiment is the same as that of the hydrogen generation system according to the first to third embodiments. Since the liquid selection determination method is different from those of the first to third embodiments, the liquid selection determination method of the fourth embodiment will be described in detail below with reference to FIG.

  When the liquid selection determination process by the liquid selection determination unit 8 a is started, first, the temperature detector 13 detects the temperature T in the hydrogen generating material storage container 1. Then, the detected temperature T is compared with a preset first set temperature T_1 and a second set T_2 that satisfy T_2 <T_1. Usually, T_1 is set within a range of 45 ° C to 60 ° C, and T_2 is set within a range of 30 ° C to 45 ° C. As a result of the comparison, when the detected temperature T is equal to or higher than the first set temperature T_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water contained in the water tank 4. When the detected temperature T is equal to or higher than the second set temperature T_2 and lower than the first set temperature T_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 is a weak alkaline aqueous solution stored in the alkaline aqueous solution tank 3b. . When the detected temperature T is lower than the second set temperature T_2, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is a strong alkaline aqueous solution stored in the alkaline aqueous solution tank 3a.

  Here, the reason why two types of alkaline aqueous solutions having different pH values are used will be described. In the case where the alkaline aqueous solution having a large pH value satisfies the relationship T <T_2 using the fact that the ratio of removing the oxide film on the surface of the hydrogen generating material 10 is larger than the alkaline aqueous solution having a small pH value. Since the temperature in the hydrogen generating material container 1 is low and the reaction rate of the hydrogen generating reaction is low, hydrogen is generated from the strong alkaline aqueous solution and the hydrogen generating material 10 having a higher hydrogen generating rate than the weak alkaline aqueous solution. The strong alkaline aqueous solution has a higher ratio of removing the oxide film on the surface of the hydrogen generating material 10 than the weak alkaline aqueous solution, and the restart time required for generating hydrogen again can be shortened. In the case of T_2 ≦ T <T_1, since the oxide film can be removed even with a weak alkaline aqueous solution having a hydrogen generation rate lower than that of the strong alkaline aqueous solution, hydrogen is generated from the weak alkaline aqueous solution and the hydrogen generating material 10. I decided to let them.

  The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material containing solution 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10. Thereafter, the above-described processing is repeated until the user receives an instruction to end hydrogen generation from a portion not shown in FIG. When the user receives an instruction to end hydrogen generation, the process ends.

  As described above, according to the hydrogen generation system of the fourth embodiment, the temperature T in the hydrogen generating material storage container 1 when the liquid supply to the hydrogen generating material 10 is started is detected, and the detected temperature T is T_2 <T_1. When the relationship of T_1 ≦ T is satisfied with respect to the first set temperature T_1 and the second set temperature T_2 set in advance satisfying the above, water stored in the water tank 4 is supplied to the hydrogen generating material 10. , T_2 ≦ T <T_1, the weak alkaline aqueous solution stored in the alkaline aqueous solution tank 3b is supplied to the hydrogen generating material 10, and when the relationship T <T_2 is satisfied, the weak aqueous alkaline solution is stored in the alkaline aqueous solution tank 3a. Since the strong alkaline aqueous solution is supplied to the hydrogen generating material 10, when the temperature in the hydrogen generating material storage container 1 is low, the temperature in the hydrogen generating material storage container 1 is maintained. Flip and by reacting the hydrogen evolution rate of the large weak alkaline aqueous solution or a strong alkaline aqueous solution and a hydrogen generating material 10 than water can reduce the restart time required to generate the hydrogen again.

(Embodiment 5)
Hereinafter, the hydrogen generation system according to Embodiment 5 of the present invention will be described. The difference from the first embodiment is that the type of liquid to be supplied to the hydrogen generating material 10 is determined based on not only the hydrogen generation stop time but also the temperature in the hydrogen generating material storage container 1. is there.

  FIG. 5 is a diagram illustrating a schematic configuration of the hydrogen generation system according to the fifth embodiment. 5, the same components as those in FIGS. 1 and 3 are denoted by the same reference numerals, and the description thereof is omitted.

  The temperature detector 13 detects the temperature in the hydrogen generating material storage container 1. The liquid selection determination unit 8b determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material 10. The liquid selection determination unit 8 b includes a timer 6 and a hydrogen generation stop time calculation unit 7, and the state of hydrogen generation in the hydrogen generation material storage container 1 and the hydrogen generation material storage container 1 detected by the temperature detector 13. The hydrogen generation material storage container when the temperature inside is monitored, the hydrogen generation stop time that is an elapsed time since the generation of hydrogen by the previous liquid supply stopped, and the liquid supply to the hydrogen generation material 10 is started Based on the temperature in 1, the type of liquid to be supplied to the hydrogen generating material 10 next is determined.

  The overall operation of the hydrogen generation system according to the fifth embodiment is the same as in the first to fourth embodiments. Since the liquid selection determination method is different from those of the first to fourth embodiments, the liquid selection determination method according to the fifth embodiment will be described below in detail with reference to FIG.

  When the liquid selection determination process by the liquid selection determination unit 8b is started (step S301), first, a hydrogen generation stop time t_stop, which is an elapsed time since the generation of hydrogen by the previous liquid supply stopped, is set to the timer 6 and the hydrogen generation. Calculation is performed using the stop time calculation unit 7 (step S302). Then, the calculated hydrogen generation stop time t_stop is compared with a preset set time t_stop_1 (step S303). Usually, t_stop_1 is set within a range of 30 minutes to 50 minutes.

  As a result of the comparison, when the hydrogen generation stop time t_stop is within the set time t_stop_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water stored in the water tank 4 (step S307). When the hydrogen generation stop time t_stop is longer than the set time t_stop_1, the temperature T in the hydrogen generating material container 1 is detected (step S304). Then, the detected temperature T is compared with a preset temperature T_1 (step S305). Usually, T_1 is set within a range of 35 ° C to 50 ° C. As a result of the comparison, when the detected temperature T is equal to or higher than the set temperature T_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water stored in the water tank 4 (step S307). When the detected temperature T is lower than the set temperature T_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is an alkaline aqueous solution stored in the alkaline aqueous solution tank 3 (step S306).

  The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10 (step S308). Thereafter, the process of steps S304 to S309 is repeated until a user's instruction to end hydrogen generation is received from a portion not shown in FIG. 5 (step S309).

  In step S309, upon receiving an instruction from the user not to generate hydrogen generation from a portion not shown in FIG. 5, the process proceeds to step S310, the operation of the hydrogen generation system is stopped, and zero is substituted for the hydrogen generation stop time t_stop. As a result, t_stop is reset. Then, the process returns to step S302, and the hydrogen generation stop time t_stop is counted until the next liquid supply is started.

  According to the hydrogen generation system of the fifth embodiment as described above, the calculation of the hydrogen stop time, which is the elapsed time since the generation of hydrogen from the hydrogen generation material 10 by the previous liquid supply stops, and the hydrogen generation material 10 The type of liquid to be supplied to the hydrogen generating material 10 is next determined based on the temperature in the hydrogen generating material storage container 1 when starting the liquid supply to the liquid, and a predetermined liquid is supplied based on the determination result. Since the hydrogen generation material storage container 1 is supplied from the portion 11, the elapsed time since the generation of hydrogen from the hydrogen generation material 10 due to the previous liquid supply to the hydrogen generation material 10 has stopped is long. When the temperature in the generating material storage container 1 is low, the restart time required for generating hydrogen again by reacting the aqueous alkali solution having a hydrogen generation rate larger than that of water with the hydrogen generating material 10. It can be shortened. Even if the timer 6 and the hydrogen generation stop time calculation unit 7 for calculating the hydrogen generation stop time or the temperature detector 13 for detecting the temperature in the hydrogen generation material storage container 1 has a problem, the hydrogen generation material Since the type of liquid to be supplied to the hydrogen generating material 10 next can be determined based on the temperature in the storage container 1 or the hydrogen generation stop time, a highly stable system can be provided.

(Embodiment 6)
The fuel cell system according to Embodiment 6 of the present invention uses the hydrogen generation system of Embodiments 1 to 5 as a hydrogen supply source. Thereby, it is possible to construct a fuel cell system equipped with a hydrogen generation system with a short restart time required to generate hydrogen again.

(Embodiment 7)
Hereinafter, a fuel cell system according to Embodiment 7 of the present invention will be described. FIG. 6 is a diagram illustrating a schematic configuration of the fuel cell system according to the seventh embodiment. 6, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The fuel cell system of Embodiment 7 includes a fuel cell 21, a voltage detector 22, a current detector 23, a low-pass filter (LPF) 24, a secondary battery charging circuit control unit 25, a secondary battery charging circuit 26, and a secondary battery. 27 and a DC-DC converter 28. The output of the DC-DC converter 28 is connected to an external load 29.

  The voltage detector 22 is connected in parallel with the fuel cell 21 via the LPF 24 that cuts high-frequency noise, and detects the voltage of the fuel cell 21. The current detector 23 is connected in series with the fuel cell 21 and detects the current of the fuel cell 21. The secondary battery charging circuit control unit 25 controls the secondary battery charging circuit 26 based on the voltage value of the fuel cell 21 detected by the voltage detector 22 and the current value of the fuel cell 21 detected by the current detector 23. Control. The secondary battery charging circuit 26 charges the secondary battery 27 according to the control from the secondary battery charging circuit control unit 25. The secondary battery 27 is connected to a DC-DC converter 28 and supplies a stable direct current to an external load 29 such as a portable electronic device via the DC-DC converter 28.

  Further, the fuel cell system of Embodiment 7 includes a hydrogen generating material storage container 1, a liquid selection valve 2, an alkaline aqueous solution tank 3, a water tank 4, a liquid selection valve control unit 5, a liquid selection determination unit 8c, and a liquid supply unit 11. The hydrogen generation system including the hydrogen supply unit 12 is further provided as a hydrogen supply source of the fuel cell 21. In addition, 12 in the figure was called a “hydrogen discharger” in Embodiments 1 to 5 because the hydrogen generated in the hydrogen generating material storage container 1 was discharged. Then, since hydrogen generated in the hydrogen generating material storage container 1 is supplied to the fuel cell 21, it is referred to as a “hydrogen supply unit”.

  The liquid selection determination unit 8c determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material 10. The liquid selection determination unit 8 c includes a timer 6 and a power generation stop time calculation unit 9, and generates power from the fuel cell 21 based on the voltage value detected by the voltage detector 22 and the current value detected by the current detector 23. The state should be monitored, and the hydrogen generation material 10 should be supplied next based on the power generation stop time that is the elapsed time since the power generation of the fuel cell 21 using the hydrogen generated by the previous liquid supply as the fuel is stopped. Determine the type of liquid. The hydrogen supply unit 12 is connected to the negative electrode of the fuel cell 21, and supplies hydrogen generated in the hydrogen generating material storage container 1 to the fuel cell 21.

  Whether or not the power generation of the fuel cell 21 is stopped is determined, for example, that the power generation of the fuel cell 21 is stopped when the actually detected voltage value is equal to or less than a predetermined voltage value corresponding to the detected current value. can do. The predetermined voltage value corresponding to the detected current value can be calculated based on a predetermined functional relationship between the current value and the voltage value.

  Next, the operation of the fuel cell system of Embodiment 7 will be described. First, the hydrogen generating material storage container 1 stores the hydrogen generating material 10, and the liquid is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1. In the hydrogen generating material storage container 1, the hydrogen generating material 10 and the liquid supplied from the liquid supply unit 11 react to generate hydrogen from the hydrogen generating material 10. The generated hydrogen is supplied to the fuel cell 21 via the hydrogen supply unit 12, and the fuel cell 21 generates power.

  Next, a method for determining the type of liquid supplied from the liquid supply unit 11 to the hydrogen generating material 10 in the hydrogen generating material storage container 1 in Embodiment 7 will be described in detail with reference to FIG.

  When the liquid selection determination process by the liquid selection determination unit 8c is started, the power generation of the fuel cell 21 using the hydrogen generated by the previous liquid supply as the fuel is stopped using the timer 6 and the power generation stop time calculation unit 9. The power generation stop time t_stop that is the elapsed time of is calculated. Then, the calculated power generation stop time t_stop is compared with a preset time t_stop_1. Usually, t_stop_1 is set within a range of 30 minutes to 50 minutes. As a result of the comparison, when the power generation stop time t_stop is within the set time t_stop_1, it is determined that the liquid to be supplied to the hydrogen generating material 10 next is water contained in the water tank 4. When the power generation stop time t_stop is longer than the set time t_stop_1, it is determined that the next liquid to be supplied to the hydrogen generating material 10 is an alkaline aqueous solution stored in the alkaline aqueous solution tank 3.

The liquid selected based on the determination result is supplied from the liquid supply unit 11 into the hydrogen generating material storage container 1, and hydrogen is generated from the hydrogen generating material 10. Thereafter, the above-described processing is continued until the user receives an instruction to end the power generation of the fuel cell 21 from a portion not shown in FIG. When the user receives an instruction to end the power generation of the fuel cell 21, t_stop is reset, and the hydrogen generation stop time t_stop is counted until the next liquid supply is started.
Thus, by changing the type of liquid supplied to the hydrogen generating material 10 based on the power generation stop time of the fuel cell 21, the restart time required to generate hydrogen again can be shortened. As a result, the fuel cell The start-up time required to generate power 21 can also be shortened.

  As described above, according to the fuel cell system of the seventh embodiment, in the fuel cell system equipped with the fuel cell using the hydrogen generated from the hydrogen generating material that generates hydrogen by the reaction with water as the fuel, The power generation state is monitored, and according to the power generation stop time of the fuel cell 21, the type of liquid to be supplied next to the hydrogen generating material 10 is determined, and the predetermined liquid selected based on the determination result is supplied to the liquid supply unit. 11 is supplied into the hydrogen generating material storage container 1, it is possible to realize a fuel cell system equipped with a hydrogen generating system with a short restart time required to generate hydrogen again.

  In addition, the fuel cell system of Embodiment 7 can improve the reliability because the power generation stop time of the fuel cell 21 can be calculated more accurately using the voltage detector 22 and the current detector 23.

  In the seventh embodiment, the case where there is one kind of alkaline aqueous solution has been described, but two kinds of alkaline aqueous solutions having different pH values may be used. For example, as the alkaline aqueous solution having different pH values, a strong alkaline aqueous solution having a pH value of x and a weak alkaline aqueous solution having a pH value of y satisfying the relationship of 7 <y <x is used. x is usually in the range of pH 10 to pH 14. In this case, the power generation stop time t_stop calculated using the timer 6 and the power generation stop time calculation unit 9 is compared with the first set time t_stop_1 and the second set time t_stop_2 set in advance that satisfy t_stop_1 <t_stop_2. Normally, t_stop_1 is set within a range of 20 minutes to 35 minutes, and t_stop_2 is set within a range of 35 minutes to 50 minutes. As a result of the comparison, when the power generation stop time t_stop is within the first set time t_stop_1, water is supplied to the hydrogen generating material 10, the power generation stop time t_stop is longer than the first set time t_stop_1, and the second set time t_stop_2. If the power generation stop time t_stop is longer than the second set time t_stop_2, the strong alkaline aqueous solution is supplied to the hydrogen generating material 10. Thereafter, the above process is continued until the user receives an instruction to end the power generation of the fuel cell 21. When the user receives an instruction to end the power generation of the fuel cell 21, t_stop is reset, and the hydrogen generation stop time t_stop is counted until the next liquid supply is started. Thus, by changing the type of liquid supplied to the hydrogen generating material 10 based on the power generation stop time of the fuel cell 21, the restart time required to generate hydrogen again can be shortened. As a result, the fuel cell The start-up time required to generate power 21 can also be shortened.

  The hydrogen generation system of the present invention can be widely used in industry as a system that can shorten the startup time required for generating hydrogen. The fuel cell system of the present invention can be widely used as a portable power source.

DESCRIPTION OF SYMBOLS 1 Hydrogen generating material storage container 2 Liquid selection valve 3, 3a, 3b Alkaline aqueous solution tank 4 Water tank 5 Liquid selection valve control part 6 Timer 7 Hydrogen generation stop time calculation part 8, 8a, 8b, 8c Liquid selection determination part 9 Power generation stop Time calculation part 10 Hydrogen generating material 11 Liquid supply part 12 Hydrogen discharge part (hydrogen supply part)
13 Temperature detector 21 Fuel cell 22 Voltage detector 23 Current detector 24 LPF
25 Secondary Battery Charging Circuit Control Unit 26 Secondary Battery Charging Circuit 27 Secondary Battery 28 DC-DC Converter 29 External Load

Claims (15)

In a hydrogen generation system that generates hydrogen using a hydrogen generating material that generates hydrogen by reaction with water,
A hydrogen generating material storage container for storing the hydrogen generating material;
A liquid supply unit for supplying water or an alkaline aqueous solution to the hydrogen generating material in the hydrogen generating material storage container;
A liquid selection determination unit that determines which liquid should be supplied to the hydrogen generating material among water and an aqueous alkaline solution,
The liquid selection determination unit monitors the state of hydrogen generation in the hydrogen generating material storage container, and based on the hydrogen generation stop time that is an elapsed time since the generation of hydrogen by the previous liquid supply stopped, Next, determine the type of liquid to be supplied to the hydrogen generating material,
The liquid supply unit supplies the liquid of the type determined by the liquid selection determination unit to the hydrogen generating material in the hydrogen generating material storage container. The liquid selection determination unit
When the hydrogen generation stop time is within a preset set time, it is determined that the liquid to be supplied to the hydrogen generating material is water next,
2. The hydrogen generation system according to claim 1, wherein when the hydrogen generation stop time is longer than the set time, it is determined that a liquid to be supplied to the hydrogen generation material next is an alkaline aqueous solution. The alkaline aqueous solution includes a strong alkaline aqueous solution having a pH value of x satisfying a relationship of 7 <y <x, and a weak alkaline aqueous solution having a pH value of y,
The liquid selection determination unit
When the hydrogen generation stop time is within a first set time set in advance, it is determined that the liquid to be supplied to the hydrogen generating material next is water;
When the hydrogen generation stop time is longer than the first set time and within a preset second set time, it is determined that the liquid to be supplied to the hydrogen generating material next is a weak alkaline aqueous solution. ,
The hydrogen generation system according to claim 1, wherein when the hydrogen generation stop time is longer than the second set time, it is determined that a liquid to be supplied to the hydrogen generation material next is a strong alkaline aqueous solution. In a hydrogen generation system that generates hydrogen using a hydrogen generating material that generates hydrogen by reaction with water,
A hydrogen generating material storage container for storing the hydrogen generating material;
A liquid supply unit for supplying water or an alkaline aqueous solution to the hydrogen generating material in the hydrogen generating material storage container;
A liquid selection determination unit that determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material;
A temperature detector for detecting the temperature in the hydrogen generating material container,
The liquid selection determination unit monitors the temperature in the hydrogen generating material storage container detected by the temperature detector, and the temperature in the hydrogen generating material storage container at the start of liquid supply to the hydrogen generating material And then determining the type of liquid to be supplied to the hydrogen generating material,
The liquid supply unit supplies the liquid of the type determined by the liquid selection determination unit to the hydrogen generating material in the hydrogen generating material storage container. The liquid selection determination unit
When the temperature in the hydrogen generating material storage container is equal to or higher than a first preset temperature set in advance, it is determined that the liquid to be supplied to the hydrogen generating material is water next.
The hydrogen generation system according to claim 4, wherein when the temperature in the hydrogen generating material storage container is lower than the first set temperature, it is determined that the liquid to be supplied to the hydrogen generating material next is an alkaline aqueous solution. The alkaline aqueous solution includes a strong alkaline aqueous solution having a pH value of x satisfying a relationship of 7 <y <x, and a weak alkaline aqueous solution having a pH value of y,
The liquid selection determination unit
When the temperature in the hydrogen generating material storage container is equal to or higher than a first preset temperature set in advance, it is determined that the liquid to be supplied to the hydrogen generating material is water next.
When the temperature in the hydrogen generating material container is lower than the first set temperature and is equal to or higher than a preset second set temperature, the liquid to be supplied to the hydrogen generating material next is a weak alkaline aqueous solution. Judge that there is,
5. The hydrogen generation system according to claim 4, wherein when the temperature in the hydrogen generation material storage container is lower than the second set temperature, it is determined that the liquid to be supplied to the hydrogen generation material next is a strong alkaline aqueous solution. . In a hydrogen generation system that generates hydrogen using a hydrogen generating material that generates hydrogen by reaction with water,
A hydrogen generating material storage container for storing the hydrogen generating material;
A liquid supply unit for supplying water or an alkaline aqueous solution to the hydrogen generating material in the hydrogen generating material storage container;
A liquid selection determination unit that determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material;
A temperature detector for detecting the temperature in the hydrogen generating material container,
The liquid selection determining unit monitors the state of hydrogen generation in the hydrogen generating material storage container and the temperature in the hydrogen generating material storage container detected by the temperature detector, and detects the hydrogen generated by the previous liquid supply. Based on the hydrogen generation stop time, which is the elapsed time since the generation stopped, and the temperature in the hydrogen generation material storage container when the liquid supply to the hydrogen generation material is started, Determine the type of liquid to be supplied,
The liquid supply unit supplies the liquid of the type determined by the liquid selection determination unit to the hydrogen generating material in the hydrogen generating material storage container. The liquid selection determination unit
When the hydrogen generation stop time is within a preset set time, it is determined that the liquid to be supplied to the hydrogen generating material is water next,
If the hydrogen generation stop time is longer than the set time, check the temperature in the hydrogen generating material container,
When the temperature in the hydrogen generating material storage container is equal to or higher than a preset temperature, it is determined that the liquid to be supplied to the hydrogen generating material is water next.
The hydrogen generation system according to claim 7, wherein when the temperature in the hydrogen generating material storage container is lower than the set temperature, it is determined that the liquid to be supplied to the hydrogen generating material next is an alkaline aqueous solution. The hydrogen generating material includes at least one metal material selected from the group consisting of aluminum, magnesium, and alloys thereof;
The hydrogen generation system according to any one of claims 1 to 8, wherein the metal material includes 80% by mass or more of particles having a particle diameter of 60 μm or less.   The hydrogen generation system according to claim 9, wherein the hydrogen generating material further includes a heat generating material that generates heat by reacting with water at room temperature.   The hydrogen generating system according to claim 10, wherein the heat generating material is at least one compound selected from the group consisting of calcium oxide, magnesium oxide, calcium chloride, magnesium chloride, and calcium sulfate.   12. A fuel cell system, wherein hydrogen generated from the hydrogen generation system according to claim 1 is supplied to a fuel cell. In a fuel cell system including a fuel cell using hydrogen as a fuel,
A hydrogen generating material storage container for storing a hydrogen generating material that generates hydrogen by reaction with water;
A liquid supply unit for supplying water or an alkaline aqueous solution to the hydrogen generating material in the hydrogen generating material storage container;
A liquid selection determination unit that determines which liquid of water and alkaline aqueous solution should be supplied to the hydrogen generating material;
A hydrogen supply part for supplying hydrogen generated in the hydrogen generating material storage container to the fuel cell,
The liquid selection determination unit monitors the power generation state of the fuel cell and is based on a power generation stop time that is an elapsed time after the power generation of the fuel cell using hydrogen generated by the previous liquid supply as a fuel is stopped. Next, determine the type of liquid to be supplied to the hydrogen generating material,
The fuel supply system, wherein the liquid supply unit supplies the type of liquid determined by the liquid selection determination unit to the hydrogen generating material in the hydrogen generating material storage container. The liquid selection determination unit
If the power generation stop time of the fuel cell is within a preset time, it is determined that the liquid to be supplied to the hydrogen generating material is water next.
14. The fuel cell system according to claim 13, wherein when the power generation stop time of the fuel cell is longer than the set time, the liquid to be supplied to the hydrogen generating material next is determined to be an alkaline aqueous solution. The alkaline aqueous solution includes a strong alkaline aqueous solution having a pH value of x satisfying a relationship of 7 <y <x, and a weak alkaline aqueous solution having a pH value of y,
The liquid selection determination unit
When the power generation stop time of the fuel cell is within a preset first set time, it is determined that the liquid to be supplied to the hydrogen generating material next is water,
When the power generation stop time of the fuel cell is longer than the first set time and within a preset second set time, the liquid to be supplied to the hydrogen generating material next is a weak alkaline aqueous solution. Judgment,
14. The fuel cell system according to claim 13, wherein when the power generation stop time of the fuel cell is longer than the second set time, the liquid to be supplied to the hydrogen generating material next is determined to be a strong alkaline aqueous solution.

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