JP2006127880A - Power supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enjoy at the maximum high efficiency power generation and effect on quick charge of a fuel cell while small size and light weight are kept by mounting the fuel cell on a video camera in a divided state. <P>SOLUTION: A power generating means of the fuel cell is mounted on a video camera body, a fuel supply device attachable to and removable from the video camera body is installed, and the means such as a reformer and a hydrogen storage alloy are installed in the fuel supply means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention assumes a portable device that requires relatively large electric power, particularly a tool that requires hand-operated operation and handling with a small turn, specifically, a digital camera and a digital video camera that capture image data toward a moving object. This is a technology related to the power supply system.

  Among digital devices that require a relatively large amount of power, cameras that are important for portability, especially video cameras, have become smaller and have a large area and weight.

  Therefore, there is a need for a battery system that is even more efficient than current lithium ion secondary batteries.

  On the other hand, fuel cells that have recently attracted attention are expected to be applied not only to electric vehicles but also to portable devices in addition to their considerably high conversion efficiency.

  Here, a configuration example in applying a general fuel cell to a portable device will be described with reference to FIG.

  In the figure, 100 is a fuel cell unit, 101 is a fuel tank such as ethanol, 102 is an evaporator, 103 is a reformer that converts ethanol into a component containing hydrogen, and 104 is a hydrogen separator that extracts hydrogen from the generated component , 106 is a stack of a fuel cell main body that extracts electrons by a chemical reaction between hydrogen and oxygen, 107 is a secondary battery that is charged with electricity by the extracted electrons, and 108 is hydrogen that condenses moisture generated by the chemical reaction of the fuel cell. It is a condenser.

  Here, the process of generating electricity will be described with reference to FIG.

  When the electric supply is turned on, the control unit 110 starts the fuel supply to the fuel tank 101.

Ethanol, which is the main fuel of the fuel cell, is supplied from the fuel tank 101 to the evaporator 102. On the other hand, the control unit 110 instructs the heating unit 105 to start heating, and heats the evaporator 102 and the reformer 103. In the evaporator 102, moisture generated by a power generation action described later is also supplied in addition to the ethanol, and ethanol and moisture are evaporated and supplied to the reformer 103 by the overheating operation. In the heated reformer 103, the supplied ethanol and moisture gas is converted into CH ₃ OH + H ₂ O → CO ₂ + 3H ₂ by a catalyst such as ruthenium (Ru).
The chemical reaction occurs, and hydrogen (H ₂ ) and the like are generated. The product is separated into carbon dioxide and hydrogen by a hydrogen separator 104 using palladium (Pd) or the like, and only hydrogen is supplied to the fuel cell stack 106. The generated hydrogen is partially returned to the heating unit 105 and used for the combustion action of the heating unit.

  6 and 7 show the structure of a stack (main body) 106 of a general fuel cell using hydrogen as a fuel. In FIG. 6, 201 is a fuel electrode side gas passage, 202 is a fuel electrode (anode), 203 is a separator, 204 is a polymer solid electrolyte membrane, 205 is a separator, 206 is an air electrode (cathode), and 207 is an air electrode side gas. It is a passage. As shown in FIG. 7, these members 201 to 207 form a set of overlapping structures to form a cell, and the fuel cell main body is configured to have a structure in which the cells are stacked in a stacked structure.

Next, the power generation operation in the fuel cell main body will be described with reference to FIG. First, hydrogen as fuel is sucked from the inlet 201a of the gas passage 201 on the fuel electrode side. In the fuel electrode 203, the catalytic action of platinum
2H ₂ → 4H ⁺ + 4e ⁻
The chemical reaction occurs. The hydrogen ions generated here move through the electrolyte polymer 204. The electrolyte polymer 204 only conducts hydrogen ions, not electrons. The generated electrons flow out to an external electric circuit through the separator 205.

On the other hand, on the air electrode side, electrons flowing from the outside flow to the air electrode 206 through the separator 205. In the air electrode 206, a chemical reaction occurs between oxygen in the air sucked into the gas passage 207 from the outside and hydrogen ions conducted through the electrolyte polymer 106.
O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O

  Here, the generated moisture is discharged from the outlet 207 of the gas passage.

The overall reaction is
2H ₂ + O ₂ → 2H ₂ O
The exothermic reaction occurs and the flow of electrons is generated, so that the power generation operation is performed.

  As described above, the fuel cell stack 106 develops a power generation operation and also generates moisture and heat.

  Returning to FIG. 5, the generated water is recovered by the water condenser 108 and supplied to the evaporator 102 described above. The generated electricity is charged in the secondary battery 107 or the like and can be used as a power source for portable portable devices.

  However, as described above, the fuel cell is constituted not only by the fuel cell main body but also by a plurality of members such as a reformer and a heating unit, and is likely to be a relatively large scale system. In addition, there is a hydrogen storage alloy that omits the reformer and can store hydrogen in a raw form, but it becomes heavy.

  Furthermore, as described above, it is necessary to perform an operation such as heating to cause a chemical reaction, and much time is consumed with regard to starting and stopping, and the handling as with a conventional secondary battery is lost. Yes.

  From the above, if a conventional fuel cell is directly installed in a portable device and used for this power supply, it is expected that many unsuitable phenomena will occur not only in terms of size and weight but also in terms of start / stop and heat generation. The

Therefore, in the end, Patent Document 1 proposes a portable charger using a fuel cell for mounting a secondary battery on a main body of a portable device and charging the secondary battery.
JP-A-6-310166

  However, in Patent Document 1, since the electric power generated in the fuel cell is charged and supplied to a secondary battery once mounted on a main device such as a video camera, the usage time of the battery of the portable device is the same as in the past. It depends on the secondary battery. In other words, it does not utilize the high-efficiency power generation capability that is the original characteristic of fuel cells. In addition, the charging time of electric power can be realized in a relatively short time because it is sufficient to fill the fuel with an original fuel cell. However, in the disclosed conventional example, the charging time of the secondary battery as in the conventional case is consumed. End up.

  In order to solve the above problems, the present invention separates the fuel supply portion to the fuel cell from the portable main body, and the portable main body is equipped with the power generation unit of the fuel cell, thereby An object of the present invention is to provide a power supply system capable of enjoying a high-efficiency power supply system for a fuel cell while maintaining the size and weight.

  The present invention can solve the above problems by providing the following configuration.

  (1) In a fuel cell-driven portable portable system, a portable portable device main body is provided with a fuel cell power generation means and a short-term, low-capacity fuel storage means. A fuel extraction means for extracting fuel from the fuel storage means of the fuel cell, a fuel supply means for the fuel storage means, and a fuel supply control for controlling the fuel extraction means and the fuel supply means according to the attachment / detachment of the fuel supply device A power supply system comprising means.

  According to the present invention, by separating the fuel supply portion to the fuel cell from the portable main body, the size and weight of the portable device can be reduced, and a highly efficient power supply system for the fuel cell can be enjoyed. To.

  Examples in which the invention is implemented will be described below.

  FIG. 1 is a conceptual diagram of a power supply system for a video camera embodying the present invention.

  In the figure, 20 is a portable video camera on which a fuel cell main body is mounted, and 50 is a fuel cell charging section for supplying fuel to the fuel cells in the main body. The charging unit 50 indicates that a fuel replacement tank is inserted from the arrowed portion. As described above, this power supply system is characterized in that the fuel cell charging unit 50 is separate from the camera body 20.

  Hereinafter, the configuration and operation of the present invention will be described with reference to the detailed block diagram 2. FIG. In the figure, 10 is a fuel cell power supply system built in the main body, 11 is a hydrogen tank, 12 is a stack of fuel cell main bodies, 13 is a secondary battery, 14 is a warm water tank, 50 is a fuel cell charging unit, 51 is A fuel tank, 52 is an evaporator, 53 is a reformer, 54 is a hydrogen separation compressor unit, 55 is a heating unit, and 56 is a control unit.

  Next, the operation of the power supply system will be described. Since the basic flow includes the same overlapping parts as described in the conventional example, the relevant parts will be described with some simplification.

  The fuel tank 51 inserted from the inlet of the charging unit 50 in FIG. 2 is filled with ethanol. In this state, as shown in FIG. 1, when the charging unit 50 and the main body are combined, the microcomputer control unit 56 in FIG. 2 detects and starts the operation of the charging unit 50.

  First, supply of the filled ethanol to the evaporator 52 is started for the fuel tank 51. In the evaporator 52, in response to a command from the control unit, ethanol from the fuel tank 51 and hot water supplied from a battery body to be described later are evaporated by the amount of heat received by the heating unit 55. The heating unit 55 is also operated in response to a command from the control unit 56. The ethanol and water evaporated by the above process are sent to the reformer 53 and reformed to hydrogen and carbon dioxide by a catalyst such as Ru and the heat quantity of the heating unit 55. Here, the generated gas is extracted only by the hydrogen component by Pd in the hydrogen separation & compressor unit 54 and further supplied to the hydrogen tank 11 in the main battery 10 by the compressor. As in the conventional example, part of the hydrogen is used for the combustion stroke of the heating unit 55 and supplies heat to the reformer 53 and the evaporator 52.

  The hydrogen generated in the charging unit 50 is sequentially filled into the hydrogen tank 11 of the main body. However, since the compressor 54 fills with pressure, the hydrogen can be stored efficiently. The hydrogen is supplied from the hydrogen tank 11 to the fuel cell stack 12, and the power generation operation is started as described in the conventional example. Electricity that is not used by power generation is used to charge the secondary battery.

  The water and heat generated by the power generation operation of the fuel cell stack 12 are collected in the hot water tank 14. The insulated water tank 14 not only collects the water generated by the reaction, but also circulates the water around the fuel cell stack 12 to absorb the heat into the water and collects the water in the hot water state. ing. That is, the heat insulation water tank 14 has a heat insulation structure that can collect reaction heat together with moisture and does not release the heat capacity.

  As described above, the hot water collected in the water retention tank 14 is supplied to the evaporator 52 of the charging unit 50 and used for the ethanol reforming operation. As described above, in the present invention, heat and water generated in the fuel cell are temporarily stored in the heat retaining water tank 14, and the heat exchange system can supply water and heat according to the request for the reforming operation of the charging unit. Yes. Further, in this embodiment, when the hydrogen tank 11 is filled with hydrogen, the pressure is increased. Therefore, if the amount of heat generated at this time is also used for the recovery system of the warm water tank 14, a more efficient heat exchange system is obtained.

  The above is the operation when the main battery 10 and the charging unit 50 are combined. In this operation, hydrogen is sequentially supplied to the hydrogen tank 11 without waiting for the completion of charging of the secondary battery by the power generation operation of the fuel cell stack 12. That is, the charging time for the fuel cell depends only on the reaction rate of the reformer 53 of the charging unit 50. This is because, once the chemical reaction of the reformer is started, hydrogen can be generated at a faster rate than the charging operation of the secondary battery, so that the secondary battery can be charged by the fuel cell stack. Before completion, the hydrogen tank 11 is filled with a predetermined amount of hydrogen. Therefore, once the hydrogen filling operation as described above is completed, the main battery 10 and the charging unit 50 can be separated.

  Therefore, this time, the operation when the charging unit is disconnected will be described. The separated charging unit 50 instructs the fuel tank 51 to stop fuel supply when the control unit 56 detects the separated state. In the evaporator 52, not only ethanol but also the main body is separated, so that hot water is not supplied and supply to the reformer 53 is stopped. Then, the reforming reaction in the heating unit is finished, and the hydrogen supply to the hydrogen separation compressor 54 is also finished. Therefore, the production of hydrogen stops. At the same time, the control unit 56 stops the operations of the compressor 54 and the heating unit 55.

  On the other hand, the operation of the disconnected main battery 10 continues the power generation operation of the fuel cell as long as there is hydrogen in the hydrogen tank 11. Then, heat and moisture generated by the power generation operation are sequentially collected in the warm water tank 14. Thus, even if it isolate | separates, electric power generation operation continues. Accordingly, the main device can be turned on in this state, and the battery generated by the fuel cell can be directly used. That is, power generated with high efficiency can be directly used. Moreover, the electric power used is charging the secondary battery. For example, even when the main power supply is turned off, the fuel cell continues the power generation operation as long as hydrogen remains in the hydrogen tank, and charges the secondary battery that can be easily controlled for starting and stopping.

  In this way, the charging operation can be continued even after the main body and the charging unit are separated. This is because the fuel cell can be charged with hydrogen in a shorter time than the normal charging time of the secondary battery, and the main body can be separated for use, so that the substantial charging time is shortened.

  Further, by separating the fuel cell system, it is possible to realize a built-in main body of only the fuel cell stack, so that a compact size and a light weight can be maintained.

  Furthermore, since the heat exchange system of the exothermic reaction in the main body and the endothermic reaction in the charging portion can be realized by the heat retaining water tank, it is possible to generate power efficiently even if the fuel cell is separated.

  Next, a second embodiment of the present invention will be described with reference to FIG. In the figure, the same reference numerals as those in the first embodiment are the same, and the description is omitted. 60 is a charging part of the fuel cell, 61 is a hydrogen storage alloy, 62 is a compressor, 63 is a heating part, and 64 is a control part.

  Here, the operation when the battery body 10 and the charging unit 60 are combined will be described. Hydrogen is stored in the hydrogen storage alloy 61, and a hydrogen component can be taken out by heating. In FIG. 3, when the combination of the main battery 10 and the charging unit 60 is detected, the control unit 64 gives an instruction to the heating unit 63. The heating unit 63 starts heating and heats the hydrogen storage alloy 61 in accordance with an instruction from the control unit. Hydrogen is generated from the heated hydrogen storage alloy 61 and supplied to the compressor 62. The generated hydrogen is filled into the hydrogen tank 11 of the main battery 10 by the compressor 62.

  Since the power generation operation is the same as that of the first embodiment, the description thereof is omitted. The heat and moisture generated by the fuel cell stack 12 of the main body are collected in the heat retaining water tank 14 as described above, but the hot water is supplied to the heating unit 63 of the charging unit 60. As a result, a heat exchange system that uses the reaction heat generated in the fuel cell for an endothermic reaction to extract hydrogen is realized, and a more efficient power generation operation can be realized.

  As described above, in this embodiment, by separating the hydrogen storage alloy of the hydrogen supply means of the fuel cell into the detachable charge portion, the fuel cell portion having a relatively large weight could be removed from the main body. That is, it is possible to mount a small and lightweight fuel cell that is optimal for portable devices.

  Further, by supplying the heat generated in the fuel cell main body to the separated charge unit, a heat exchange system can be realized, and a more efficient power generation operation can be realized.

  Further, FIG. 4 shows a third embodiment in which the present invention is implemented. Similarly to the above, the parts having the same numbers have the same functions, and thus the description thereof is omitted. In the figure, 15 is a capacitor mounted on the main battery 10, 70 is a strobe mounting a charging unit of the fuel cell, 71 is a liquid hydrogen cylinder, 72 is a compressor, 73 is a heating unit, 74 is a control unit, 75 is a capacitor, Reference numeral 76 denotes a strobe light emitting circuit.

  Next, the hydrogen generation operation of the strobe unit 70 will be described. In the figure, when the strobe unit 70 is attached to the main body 10, the control unit 74 detects this and opens the valve of the liquid hydrogen cylinder. Hydrogen released from the liquid hydrogen cylinder is supplied to the compressor unit 72 and filled in the hydrogen tank 11 of the main body 10.

  Hereinafter, the power generation operation in the camera body is the same as described above. Further, the heat generated by the power generation reaction becomes hot water and is supplied to the heating unit 73 of the strobe unit 70. In the heating unit 73, in order to promote the release of hydrogen from the liquid hydrogen cylinder 71, the liquid hydrogen cylinder 71 is heated by allowing the hot water to pass through the portion where the liquid hydrogen cylinder 71 is heated. Thus, also in the present embodiment, more efficient hydrogen generation is realized by configuring a heat exchange system using moisture as a medium.

  Further, in the power generation operation in the main body 10, a part of the generated power is accumulated in the capacitor 15. This charge is charged in the capacitor 75 of the flash unit 70 when the flash power is not charged when the flash 70 is attached to the main body. Then, according to an instruction from the control unit 74, electric power is supplied to the strobe light emitting circuit with the charge charged in the capacitor 75, and the strobe light is emitted. As described above, in this embodiment, the strobe unit 70 has only a built-in portion for generating hydrogen of the fuel cell, and is not equipped with a battery for causing the strobe to emit light. And since the built-in hydrogen generation site is a relatively light component such as a liquid hydrogen cylinder, a light and compact strobe can be realized.

Conceptual diagram of a video camera system equipped with a fuel cell Block diagram of the first embodiment of the present invention Block diagram of a second embodiment embodying the present invention Block diagram of a third embodiment embodying the present invention Conventional general fuel cell block diagram Schematic diagram of the fuel cell body Overview of the fuel cell body

Explanation of symbols

20 Video camera body 10 equipped with a fuel cell Fuel cell power supply system (main battery) built in the body
11 Hydrogen tank 12 Fuel cell body 14 Insulated water tank 50 Fuel cell charging unit (charger)
51 Fuel Tank 52 Evaporator 53 Reformer 54 Compressor 55 Heating Unit 56 Control Unit

Claims (7)

  In a fuel cell-driven portable transport system, a fuel cell power generation means and a short-term, low-capacity fuel storage means are provided in a portable portable device body, and the fuel supply device detachable from the body is provided with a fuel cell. A fuel extraction means for extracting fuel from the fuel storage means, a fuel supply means for the fuel storage means, and a fuel supply control means for controlling the fuel extraction means and the fuel supply means in accordance with attachment / detachment of a fuel supply device A power supply system characterized by that.   The configuration portable device is provided with means for recovering moisture and heat generated from the power generation unit of the fuel cell, and means for temporarily storing the recovered moisture and heat, and the fuel supply device has the configuration portable device. The power supply system according to claim 1, further comprising: a receiving unit that takes in the moisture and heat from the fuel; and a recovery unit that supplies the fuel extraction unit with the moisture and heat from the receiving unit.   The power supply system according to claim 1, wherein the fuel supply means supplies hydrogen gas.   2. The power supply system according to claim 1, wherein the fuel storage means is an ethanol liquid cylinder, and the fuel extraction means is a fuel reformer.   2. The power supply system according to claim 1, wherein the fuel storage means is a hydrogen storage alloy, and the fuel extraction means is a heating means.   2. The portable light-emitting device is a digital camera device, and is a strobe light-emitting device having a strobe light emitting means in the fuel supply device and a means for supplying electric power from the portable portable device. The power supply system described.   The power supply system according to claim 1, further comprising a secondary battery provided in the portable portable device, and means for charging the secondary battery with electric power generated by the fuel cell.

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