JP2007200726A - Activating device and manufacturing method of fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an activating device of a fuel cell in which a high electromotive force can be output immediately from the loaded fuel cell so that electronic apparatuses can be utilized immediately without resulting either in a large-sizing of the fuel cell or in a large-sizing of the portable electronic apparatus. <P>SOLUTION: The activating device 20 is prepared which is independent from the fuel cell 10 and also from the portable electronic apparatus and operated by a commercial power source. The activating device 20 is mounted with the fuel cell for one minute before loading it to the portable electronic apparatus, and a constant voltage load 21 is connected while a humidified hydrogen gas is supplied to a power generation cell 12 so that a markedly large electric current than in a normal using state is made to be output from the power generation cell 12. Humidity corresponding to the value of the current becomes generated, and the wetness in the membrane electrode assembly becomes rapidly elevated, and when the fuel cell 10 is loaded to the apparatus, a large current can be output immediately by the high electromotive force. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell activation device that reacts hydrogen gas with atmospheric oxygen using a polymer electrolyte membrane, and more specifically, immediately after the start of actual power generation by quickly increasing the power generation function of the polymer electrolyte membrane. The present invention relates to an activation device independent of equipment and fuel cells, which enables high electromotive force to be used.

  A fuel cell has a remarkably large amount of electric power that can be taken out per weight per volume as compared with a conventional secondary battery, and the battery body can be used repeatedly if fuel is supplied. Therefore, it is expected to be a power source for portable electronic devices such as digital cameras, mobile phones, and notebook computers, as well as stationary power generation facilities.

  As a portable power source, a compact and light-weight one is suitable. Therefore, an air breathing type fuel cell in which oxygen and hydrogen gas in the atmosphere are reacted using a polymer electrolyte membrane has been proposed. In a power generation cell of an air breathing type fuel cell, a catalyst layer is usually disposed on both sides of a polymer electrolyte membrane. A hydrogen gas supply space for supplying hydrogen gas is disposed on one surface side of the polymer electrolyte membrane, and an oxygen diffusion space for diffusing oxygen in the atmosphere is disposed on the other surface side.

  The hydrogen gas supply space is isolated from the atmosphere and the oxygen diffusion space to avoid leakage of hydrogen gas into the atmosphere, and is connected to a fuel tank and a reformer for supplying hydrogen gas to the power generation cell. . A part of the oxygen diffusion space is open to the atmosphere, and diffuses oxygen in the atmosphere to the polymer electrolyte membrane side and diffuses water vapor generated on the polymer electrolyte membrane side to the atmosphere. Since the power generation cell has an electromotive force of 1 V or less per stage, usually, a plurality of stages are stacked and connected in series (see FIG. 1).

  The polymer electrolyte membrane contains a large amount of water in the material together with the electrolyte, and in a state where the electrolyte is sufficiently hydrated (coexistence with water molecules), hydrogen ions are smoothly transferred from the hydrogen supply space side to the oxygen diffusion space side. Can be moved. When the polymer electrolyte membrane and catalyst layer are not used (or after power generation is stopped and left for a long period of time), some of the water contained in them is lost due to evaporation, resulting in an increase in ionic conduction resistance. The power decreases.

  However, when a load is connected to the fuel cell and power generation is started, water molecules corresponding to the current taken out to the load are generated, the water content of the polymer electrolyte membrane is recovered, and the electromotive force of the power generation cell gradually increases ( (See FIG. 3). Various methods for improving the startup characteristics of the fuel cell using this phenomenon have been proposed under the names of conditioning, refresh, and startup processing.

  Patent Document 1 discloses a method for improving start-up characteristics of a fuel cell using a polymer electrolyte membrane. Here, prior to the start of actual power generation, the fuel cell is connected to a constant voltage load, and the output current that is larger than the normal load is taken out of the fuel cell, so that the moisture content of the polymer electrolyte membrane is quickly returned to the normal state. Has been recovered. In parallel with the connection to the constant voltage load, the hydrogen gas supplied to the hydrogen gas supply space is humidified, the air supplied to the oxygen diffusion space is humidified, and the heater is energized for forced heating. It has been proposed.

  Patent Document 1 also discloses a method of manufacturing a fuel cell in which a step of taking out an excessive output current from the fuel cell is added after the assembly of the fuel cell using the polymer electrolyte membrane. Similar to the method for improving the start-up characteristics, the power generation characteristics of the fuel cell can be enhanced by improving the water content of the assembled polymer electrolyte membrane.

  Patent Document 2 discloses a fuel cell operation control method using a polymer electrolyte membrane. Here, it is shown that the operating state of the power generation cell is optimized by adding the polymer electrolyte membrane to a steady state and heating it to 80 ° C. When the electromotive force of the power generation cell is detected and the rated electromotive force is not reached, the fuel cell is connected to the impedance load. By taking out an output current that is larger than the normal load from the fuel cell, the polymer electrolyte membrane is hydrated and heated to restore the power generation state to the normal state.

  Patent Document 3 shows a portable fuel cell using a polymer electrolyte membrane. Here, the power generation capacity of the power generation cell is enhanced by incorporating a fan in the casing of the fuel cell and forcibly ventilating the oxygen diffusion layer of the power generation cell.

  Patent Document 4 shows an electronic device that is detachably equipped with a fuel cell using a polymer electrolyte membrane. Here, an electromotive force of the power generation cell is increased by disposing a fan on the electronic device side adjacent to the space where the fuel cell is mounted and forcibly ventilating the oxygen diffusion layer of the power generation cell.

JP 2002-319421 A JP 2003-132922 A Japanese Patent Laid-Open No. 9-22719 JP 2002-169625 A

  If the mechanisms and devices disclosed in Patent Documents 1 to 3 are incorporated in the casing of the fuel cell in order to improve the start-up characteristics, the fuel cell becomes large and difficult to mount on a portable electronic device. If the mechanism or device disclosed in Patent Document 4 is incorporated into a portable electronic device in order to improve the starting characteristics, the fuel cell can be realized in a small size and at a low cost, but the portable electronic device is increased in size and weight. I will.

  In the first place, heating devices, humidification devices, fans, compressors, water tanks, etc. are not suitable for incorporation in portable electronic devices. Forcibly built-in causes new problems such as water supply, rust, noise, vibration, poor contact, and shortened device life. Even incorporating a constant voltage load unrelated to the original function of an electronic device is not realistic considering heat generation and weight reduction of the device.

  In addition, since the fuel cell is used as a power source for portable electronic devices, the mechanism or device added to improve the start-up characteristics must rely on the unstable output of the fuel cell at start-up. Therefore, a mechanism or device that requires a large amount of power, a microcomputer circuit that requires a stable and continuous power supply, or the like cannot be employed. Therefore, simple control that secures a large safety factor (= small output current) is used, and it takes a long time to improve the power generation performance to the normal state.

  In addition, if the start-up characteristic improvement operation was started after being mounted on the electronic device, the electronic device loaded with the fuel cell was immediately used without waiting for the end of the start-up characteristic improvement operation to start using the electronic device. It cannot be used.

  The present invention provides an apparatus for activating a fuel cell that can immediately use the electronic device by immediately outputting a high electromotive force from the loaded fuel cell without causing an increase in the size of the fuel cell or a portable electronic device. The purpose is that.

  The activation device of the present invention is an activation device that improves the starting characteristics of a fuel cell having a polymer electrolyte layer. Holding means for holding the fuel cell detachably and operable; operating means connected to the power generation cell of the fuel cell held by the holding means to pass current to the fuel cell; and the polymer An operation assisting means for activating the power generation function of the electrolyte layer. Then, by operating the driving means in a state where the driving auxiliary means is operated, the power generation based on the current-voltage condition impossible in the polymer electrolyte layer in the initial state where the driving auxiliary means is not operated is forced. It is.

  In the present invention, since the fuel cell is mounted on the activation device before being loaded into the device to enhance the starting characteristics of the fuel cell, when the fuel cell is loaded into the device, the fuel cell can immediately output a high electromotive force. .

  In addition, since the activation device is a device that is independent from both the device and the fuel cell, it is possible to design with the highest priority on function by ignoring the built-in fuel cell or the built-in device. Since neither the fuel cell nor the device is built in, the fuel cell and the device are not increased in size, increased in number of parts, and increased in cost due to the activation device.

  In addition, without relying on the output of the fuel cell in the initial state, it is possible to select the driving means and the driving assistance means with the highest priority on improving the startup characteristics of the fuel cell, so it is extremely short while ensuring a sufficient safety factor. Can improve the starting characteristics of the fuel cell. In other words, the current of each power generation cell of the fuel cell is detected momentarily through the current exceeding the short-circuit by applying a voltage of the opposite polarity to the power generation from the outside, or using the microcomputer control device, It is also possible to control the driving assistance state.

  Hereinafter, an activation device according to an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the limited configuration of the activation device described below. The configuration of the activation device is not limited as long as the activation characteristics are improved by mounting the fuel cell for a short time before loading the device. Other embodiments in which part or all of them are replaced by the alternative configuration can also be realized.

  The activation device of the present invention can be applied to a small fuel cell that is detachably mounted on a portable electronic device such as a digital camera, a digital video camera, a small projector, a small printer, or a notebook computer. In addition, the fuel tank and the power generation unit may be either an integral non-separable type or a detachable / replaceable type as long as at least the power generation unit can be detached from the device and attached to the activation device. Instead of the fuel tank, a fuel cell that generates hydrogen gas from a liquid fuel such as methanol, another gaseous fuel, or a solid fuel using a reformer may be used.

  In the case of a fuel cell in which the fuel supply system is integrated with the power generation unit, hydrogen gas used for operation for improving the start-up characteristics may be supplied from its own fuel supply system, or from the activation device. You may supply.

  The fuel cell structure, power cell material and assembly structure, operating principle, manufacturing method, polymer electrolyte membrane activation method, and the like disclosed in Patent Documents 1 to 4 are different from the spirit of the present invention. Some illustrations are omitted, and detailed explanation is also omitted.

<First Embodiment>
FIG. 1 is a perspective view illustrating the configuration of the activation device according to the first embodiment, FIG. 2 is an explanatory diagram of a state in which a fuel cell is connected to a load, and FIG. 3 is a diagram of startup characteristics of the fuel cell in an initial state. 4 is a schematic view of a state in which a fuel cell is mounted on the activation device. FIG. 5 is an explanatory diagram of an activation device that humidifies hydrogen gas using a humidifier, and FIG. 6 is a diagram illustrating activation by humidification. FIG. 7 is an explanatory diagram of an activation device for supplying water to the oxygen diffusion electrode using a water supply device, and FIG. 8 is a diagram for explaining activation by water supply. FIG. 9 is a diagram for comparing activation processes by humidification and water supply.

  As shown in FIG. 1, the fuel cell 10 includes a cell stack 10S in which a plurality of power generation cells 12 are stacked and connected in series. The power generation cell 12 is sandwiched and stacked between the fuel electrode current collector 17 and the oxygen electrode current collector 16, and is assembled by pressurizing the whole in the stacking direction using the pressure plates 19A and 19B.

  In the power generation cell 12, the fuel diffusion electrode 15 is brought into contact with one surface of the membrane electrode assembly 12M, and the oxygen diffusion electrode 14 is brought into contact with the other surface. The membrane electrode assembly 12M has catalyst layers formed on both sides of the polymer electrolyte membrane. In the catalyst layer in contact with the fuel diffusion electrode 15, the hydrogen gas is decomposed into hydrogen atoms by the catalytic reaction and ionized, and the hydrogen ions are supplied to the polymer electrolyte membrane. In the catalyst layer in contact with the oxygen diffusion electrode 14, oxygen combines with hydrogen ions picked up from the polymer electrolyte membrane by overcoming the electromotive force of the power generation cell 12 by a catalytic reaction to generate water molecules. The polymer electrolyte membrane moves hydrogen ions from the fuel diffusion electrode 15 side to the oxygen diffusion electrode 14 side.

  A Nafion 112 (trademark) membrane manufactured by DuPont was used as the polymer electrolyte membrane of the power generation cell 12. Further, HiSPEC 1000 (trademark) manufactured by Johnson & Massey was used as a catalyst powder for forming the catalyst layer, and Nafion (trademark) solution manufactured by DuPont was used as the electrolyte solution.

A mixed dispersion of the catalyst powder and the electrolyte solution was prepared and formed on a fluororesin (PTFE) sheet using a doctor blade method to obtain a catalyst sheet. Next, the produced catalyst sheet was hot-press transferred onto a polymer electrolyte membrane at 150 ° C. and 10 MPa (100 kgf / cm ² ) by a decal method to produce a membrane electrode assembly 12M.

  The fuel diffusion electrode 15 is disposed in a recess formed in the fuel electrode current collector 17 and communicates with the fuel main flow path 13A penetrating the cell stack 10S. Since the outer periphery of the fuel diffusion electrode 15 is sealed, hydrogen gas does not leak into the atmosphere and the oxygen diffusion electrode 14. The oxygen diffusion electrode 14 is stored in a recess formed in the oxygen electrode current collector 16, and a part of the side surface is opened to the atmosphere through the air intake port 11 of the oxygen electrode current collector 16.

  As the fuel diffusion electrode 15 and the oxygen diffusion electrode 14, a conductive carbon cloth electrode (manufactured by E-TEK) was adopted. The membrane electrode assembly 12M manufactured as described above is sandwiched between the fuel diffusion electrode 15 and the oxygen diffusion electrode 14, and the outside thereof is sandwiched between the fuel electrode current collector 17 and the oxygen electrode current collector 16, and each stage of the cell stack 10S. Was made. The fuel cells 10 were assembled by stacking the steps and fastening them with the pressure plates 19A and 19B.

  The oxygen electrode current collector 16, the power generation cell 12 (membrane electrode assembly 12 </ b> M), the fuel electrode current collector 17, and the pressure plate 19 </ b> A in each stage penetrate through the fuel main flow channel 13 </ b> A and the water supply main flow channel 13 </ b> B in the same plane position. A hole is formed. At the end of the fuel main flow path 13A located on the lower surface of the pressure plate 19A, a connection port is provided that can connect / disconnect the pipeline while maintaining the air tightness of the fuel main flow path 13A. Such a connection port may be a fitting connector in which both sealing balls move by forming a gap by connecting the connector and the plug. A fuel tank (not shown) that normally stores hydrogen gas at high pressure using a hydrogen storage alloy is connected to the connection port of the fuel main flow path 13A.

  The activation device 20 guides a positioning mechanism (not shown) to mount the fuel cell 10 from above, thereby positioning and holding the fuel cell 10 in the holding mechanism 20A. A fuel supply connector 20B and a water supply connector 20C, which are detachable from the connection ports of the fuel main flow path 13A and the water supply main flow path 13B, are connected to the floor surface of the holding mechanism 20A at the same time as the fuel cell 10 is mounted. Be placed. Further, on the rising surface of the holding mechanism 20A, the connecting electrode 20D that can contact the fuel electrode current collector 17 and the oxygen electrode current collector 16 at each stage and take out current simultaneously with the mounting of the fuel cell 10, respectively. 20E is arranged.

  The fuel cell 10 is schematically illustrated as shown in FIG. As shown in FIG. 2, the fuel tank 10G is connected to the fuel cell 10, and hydrogen gas adjusted to a pressure slightly higher than the atmospheric pressure is supplied to the fuel diffusion electrode 15 through the fuel main channel 13A. Oxygen in the atmosphere is taken in from the air intake 11 and supplied to the oxygen diffusion electrode 14 by natural diffusion. In such a normal operation state, the oxygen electrode current collector 16 and the fuel electrode current collector 17 were connected to the constant voltage load 21 to start power generation. Hydrogen and air were supplied unhumidified, room temperature was 25 ° C., and relative humidity was 50%.

  FIG. 3 shows a comparison between the power generation characteristics in the initial state and the power generation characteristics after 5 minutes of power generation. The power generation for 5 minutes was performed with the cell voltage maintained at 0.6V. As shown in FIG. 3, the electromotive force of the fuel cell 10 is increased by the operation for 5 minutes, and the current value at 0.6 V output has nearly doubled. For various activation processes described below, this power generation is referred to as “normal power generation” and is used as a comparative example.

  As shown in FIG. 4, the activation device 20 includes a constant voltage load 21 and a driving assistance mechanism 30. The constant voltage load 21 is an electronic load that detects the terminal voltage of the constant voltage load 21 and changes the power consumption every moment so as to keep the terminal voltage constant. The constant voltage load 21 is realized by, for example, a general constant voltage circuit that controls the base voltage of a power transistor attached to a heat sink with a constant voltage of a Zener diode.

  The activation device 20 supplies hydrogen gas to the fuel cell 10 from the fuel supply connector 20B through the fuel main channel 13A. Hydrogen gas taken out from a fuel tank (not shown) built in the activation device 20 is adjusted to the same pressure as in a normal operation state, and is humidified using a humidifier 22 (FIG. 5).

  The activation device 20 includes a water tank and a pump (not shown). The water taken out from the water tank is pumped out, and water can be injected from the water supply connector 20C to the oxygen diffusion electrode 14 of the fuel cell 10 through the water supply main channel 13B to supply water to the oxygen supply side of the power generation cell 12.

  As shown in FIG. 5, the activation device 20 includes a hydrogen gas humidifier 22 as an operation assist mechanism 30. The humidifier 22 has a water retention space that is disposed in the hydrogen gas supply system and is capable of supplying water from the outside, and a heater that is disposed outside the water retention space, and energizes the heater to vaporize the water in the water retention space. As a result, the hydrogen gas passing through the water retention space is humidified.

  The constant voltage load 21 was operated while the hydrogen gas was humidified and supplied to the fuel diffusion electrode 15. As shown in FIG. 6, when the power generation characteristics were measured after generating the power for 5 minutes while keeping the cell voltage at 0.6 V, the characteristics were improved more quickly than in the case of normal power generation without humidification.

  As shown in FIG. 7, the activation device 20 includes a water feeder 23 as an operation assistance mechanism 30 that injects water into the oxygen diffusion electrode 14 and supplies water to the oxygen supply side of the power generation cell 12. After injecting water into the oxygen diffusion electrode 14 and diffusing it to the oxygen supply side of the power generation cell 12, the constant voltage load 21 was operated. As shown in FIG. 8, when the power generation characteristics after measuring the power for 5 minutes while keeping the cell voltage at 0.6V, the characteristics were improved more quickly than in the case of normal power generation without water supply.

  Changes in the current value taken out to the constant voltage load 21, that is, recovery of power generation performance, when the humidifier 22 is used to humidify the hydrogen gas and when the water generator 23 is used to supply water to the power generation cell 12. The processes were compared. As shown in FIG. 9, in the case of humidification, a large current can be taken out immediately after the start of power generation as compared with the normal power generation, but in the case of water supply, a gradually larger current can be taken out. However, in any case, the characteristic recovery was quicker and higher than that of the normal power generation, that is, the characteristic recovery over the normal power generation was obtained in 1 minute or less compared to the normal power generation requiring about 5 minutes.

  In addition, when the change in the internal resistance of the fuel cell 10 after power generation is compared, the resistance which was about 8Ω in the initial state has decreased to about 0.6Ω after normal power generation, whereas it is 0 when water is supplied. .3Ω, and when humidified, it could be greatly reduced to 0.2Ω. The state of change in the current value in the constant voltage power generation from the initial state of the fuel cell 10 (power generation cell 12) is as shown in FIG. By attaching the fuel cell 10 to the activation device 20 and performing at least one of humidification and water supply, preferably both, recovery to a much higher power generation performance in a much shorter time than when performing normal power generation Is realized. The improvement of the current value can be seen greatly.

  The hydrogen supply side of the membrane electrode assembly 12M of the power generation cell 12 is difficult to supply water from the outside in the sealed space, and waits for the water molecules generated on the oxygen supply side to diffuse in concentration, so that the ion conductivity becomes wet. Recover. In the case of humidification, water can be replenished directly to the hydrogen supply side of the membrane electrode assembly 12M without waiting for such time-consuming concentration diffusion, so that a larger current can be taken out compared with normal power generation immediately after the start of power generation. . In the case of water supply, concentration diffusion in the film thickness direction of the membrane electrode assembly 12M is promoted without waiting for generation of water molecules by power generation, so that a large current can be taken out gradually.

  Similar results can be obtained when the atmosphere is humidified instead of hydrogen gas. Humidification of the atmosphere can be realized by installing the fuel cell in a constant temperature and humidity chamber maintained in a predetermined temperature and humidity state and operating.

Second Embodiment
FIG. 10 is an explanatory diagram of the configuration of the activation device that performs heater heating, and FIG. 11 is an explanatory diagram of the configuration of the activation device of the second embodiment. The activation device 40 of the second embodiment is configured in the same manner as in the first embodiment, except that heater heating is performed with humidification. Therefore, the description will be made with reference to FIGS. 1 to 9, and the same reference numerals are given to the components common to FIGS. 4 and 5, and the detailed description will be omitted.

  As the driving assist mechanism 30 (FIG. 4), as shown in FIG. 10, when the heater 24 is used and the constant voltage load 21 is operated while the fuel cell 10 is heated, power generation is performed. A decrease in the compared current value and an increase in the internal resistance of the power generation cell 12 were observed. This is presumably because moisture was further lost by heating, the membrane electrode assembly 12M was dried, and the ionic conductivity of the polymer electrolyte membrane was lowered.

  As shown in FIG. 11, in the activation device 40 of the second embodiment, the heater 24 and the humidifier 22 are mounted as the driving assistance mechanism 30 (FIG. 4). The heater 24 is disposed in the holding mechanism 20A so as to surround the outer periphery of the fuel cell 10 shown in FIG. 1 and is energized using a commercial power source, thereby forcing the cell stack 10S from the outside to 80 degrees C. Heat.

  As in the first embodiment, the power generation is started by operating the constant voltage load 21 while heating by the heater 24 in parallel with the humidification supply of the hydrogen gas by the humidifier 22, as shown in FIGS. The startup characteristics were improved more than that. That is, the current value at 0.6 V output increased immediately after the start of power generation, the amount of water generation increased, and the heating was overcome and the recovery of the wetness of the membrane electrode assembly 12M was accelerated.

<Third Embodiment>
FIG. 12 is an explanatory diagram of the configuration of the activation device according to the third embodiment, and FIG. 13 is a diagram comparing the power generation performance with and without the use of the blower. The activation device 50 of the third embodiment is configured in the same manner as in the first embodiment except that activation is performed using the blower 25. Therefore, the description will be made with reference to FIGS. 1 to 9, and the same reference numerals are given to the components common to FIGS. 4 and 5, and the detailed description will be omitted.

  As shown in FIG. 12, in the activation apparatus 50 of 3rd Embodiment, the blower 25 was provided as the driving assistance mechanism 30 (FIG. 4). The blower 25 is disposed in the holding mechanism 20A so as to face the air intake port 11 of the cell stack 10S shown in FIG. 1, and forcibly sends air into the air intake port 11 penetrating the cell stack 10S. Thereby, even after the start of power generation, the oxygen concentration in the space of the air intake port 11 is maintained high, and the amount of oxygen supplied to the oxygen diffusion electrode 14 increases.

  When the constant voltage load 21 was activated while the blower 25 of the activation device 50 was activated, power generation was started. As shown in FIG. 13, the maximum current was 30% as compared with the case where the blower was not used. Improved. As a result, the amount of current when activating the fuel cell 10 can be increased, water generation can be promoted, the wetness of the membrane electrode assembly 12M can be quickly increased, and the activation time can be shortened. .

  In particular, in the fuel cell 10 having a small rated current, the activation process is difficult at the rated current, but the blower 25 allows a current sufficient for activation to flow and shortens the activation time. We were able to.

  The blower 25 shown in FIG. 12 may be replaced with air blowing using a compressor. Equally in the function of promoting the diffusion of oxygen through the air intake 11 and the discharge of excess water vapor, a rapid activation effect is obtained as well.

<Fourth embodiment>
FIG. 14 is an explanatory diagram of the configuration of the activation device of the fourth embodiment, FIG. 15 is an explanatory diagram of a configuration in which a DC power source and a water feeder are used together as an operation assisting mechanism, and FIG. 16 is a combination of a DC power source and a water feeder. It is a diagram explaining the activation effect. The activation device 60 of the fourth embodiment is configured in the same manner as in the first embodiment except that the current output from the power generation cell 12 is forcibly increased using the DC power supply 26. Therefore, the description will be made with reference to FIGS. 1 to 9, and the same reference numerals are given to the components common to FIGS. 4 and 5, and the detailed description will be omitted.

  As shown in FIG. 14, the activation device 60 of the fourth embodiment applies a voltage having a polarity opposite to that of the electromotive force between both poles of the power generation cell 12 to intentionally increase the water generation amount, thereby generating the power generation cell. 12 activation processes are performed. That is, a positive voltage is applied to the fuel diffusion electrode 15 side of the membrane electrode assembly 12M, and a negative voltage is applied to the oxygen diffusion electrode 14 side. As a result, the amount of water generated in the oxygen diffusion electrode 14 of the membrane electrode assembly 12M is forced by flowing a current more than the short circuit between the fuel diffusion electrode 15 side and the oxygen diffusion electrode 14 side of the membrane electrode assembly 12M. Increase rapidly.

  The fuel cell 10 was produced in the same manner as in the first embodiment. The activation device 60 includes a DC power supply 26 and an operation assist mechanism 30. The DC power source 26 is a constant current power source that operates using a commercial power source, and can set a limit voltage and an output current. The DC power source 26 changes the output voltage within a range that does not exceed the set limit voltage and maintains the output current at the set value.

  As shown in FIG. 15, the driving assistance mechanism 30 is the same water supply 23 as in the first embodiment. The water feeder 23 pushes out water taken out from a water tank (not shown) built in the activation device 60 by a pump (not shown) built in the activation device 60 and sends it into the water supply main flow path 13B (see FIG. 1). . The water poured into the oxygen diffusion electrode 14 through the water supply main channel 13B wets the oxygen diffusion electrode 14 side of the membrane electrode assembly 12M and wets the membrane electrode assembly 12M.

  The fuel cell 10 is set in the holding mechanism 20A of the activation device 60 (see FIG. 1), and the oxygen diffusion electrode 14 is used as a cathode and the fuel diffusion electrode 15 is used as an anode by a DC power supply 26 connected to the connection electrodes 20D and 20E. A DC voltage was applied for 2 minutes.

  Comparison between the case where the constant voltage load is connected and activated while supplying water to the power generation cell 12 (first embodiment) and the case where the constant current is forced to flow while supplying water to the power generation cell 12 and activated. The results are shown in FIG. A case where the constant current value is set to 0.5 A and a case where the constant current value is set to 1.0 A are shown by voltage-current characteristics after activation. By applying a DC voltage and applying a constant current, a large amount of water can be generated even in an initial state where the wetness is low, and the wetness of the membrane electrode assembly 12M can be rapidly increased, and the power generation characteristics are greatly improved. ing.

  Instead of injecting water into the power generation cell 12 using the water supply device 23, even if the humidifier 22 is used to humidify the hydrogen gas, the combined use with the DC power source 26 enables faster power generation than in the first embodiment. Improvement in characteristics was observed.

  Further, the water feeder 23 may be replaced with a water vapor supply device that heats water taken out from a water tank (not shown) built in the activation device 60, vaporizes it, and sends it to the main water supply channel 13B (see FIG. 1). . The activation device 60 can eliminate the need for a pump, and simultaneously achieve humidification and heating of the membrane electrode assembly 12M, so that the DC power supply 26 can achieve the same constant current at a lower voltage. Since the liquid water does not obstruct the diffusion of oxygen by covering the surface of the membrane electrode assembly 12M, the DC power source 26 can realize a constant current more reliably than the water supply device 23.

  Further, even when the heater 24 for heating the cell stack 10S from the outside is used in combination as in the second embodiment, further activation can be performed by applying a DC voltage from the DC power supply 26.

  On the other hand, when the DC power supply 26 is connected to the initial state (dry state) of the fuel cell 10 without humidification or water supply, and the constant current flows in the same manner, the internal resistance of the power generation cell 12 increases, and power generation occurs. The characteristics deteriorated. This is presumably because the water in the material of the membrane / electrode assembly 12M evaporated due to the heat generated by voltage application, the polymer electrolyte membrane was further dried, and the ionic conductivity was lowered.

<Fifth Embodiment>
FIG. 17 is an explanatory diagram of the inversion phenomenon in the power generation cell of the cell stack. In the figure, (a) shows a normal power generation state, and (b) shows a state where inversion has occurred.

  As shown in FIG. 17A, in the power generation in the cell stack 10S in which a plurality of power generation cells 12 are connected in series, when a large current flows, the voltage of one of the power generation cells 12 is greatly increased. Further, as shown in FIG. 17B, a phenomenon in which a reverse voltage is applied to one power generation cell 12 is observed.

  This phenomenon is explained as follows. Consider a fuel cell in which six-stage power generation cells 12 are stacked as shown in FIG. When the constant voltage load 21 is adjusted so that the output voltage of the cell stack 10S is 3.0V, all the voltages of the power generation cells 12 in each stage are 0.5V if there is no variation in the power generation cells 12.

  However, if there are variations in the state of the power generation cells 12 at each stage, a large load is applied to the power generation cells 12 with poor characteristics, as shown in FIG. An electromotive force is applied. This phenomenon is called inversion.

  Therefore, in the normal power generation of the cell stack 10S in which the fuel cell 10 is loaded into the device and the power is taken out, a high safety factor is ensured and only a smaller current can be taken out than the state of the single power generation cell 12. In particular, under conditions where oxygen in the atmosphere is taken into the power generation cell 12 by natural diffusion or when humidification of hydrogen gas is not performed, the oxygen conductivity is insufficient and the ionic conductivity decreases due to the drying of the membrane electrode assembly 12M. The pole is likely to occur.

  However, in the first to fourth embodiments, the fuel cell 10 is taken out from a device whose environmental conditions are indefinite, and attached to the single activation devices 20, 40, 50, 60 that ensure the environmental conditions to be constant, A humidifier 22, a water feeder 23, a heater 24, a blower 25, etc. are used. As a result, it is possible to perform a stable activation process while avoiding the polarization of the power generation cell 12.

  As shown in FIG. 1, the driving assistance mechanism 30 uses the connection electrodes 20 </ b> D and 20 </ b> E corresponding to the fuel electrode current collector 17 and the oxygen electrode current collector 16 at each stage, for each power generation cell 12 at each stage. In addition, the power generation performance of the fuel cell 10 is restored. However, the driving assistance mechanism 30 according to the first to fourth embodiments is configured by connecting the constant voltage load 21 and the DC power source 26 using the extraction electrodes 18A and 18b that extract the electric power from the cell stack 10S, thereby configuring the cell stack 10S. A plurality of power generation cells 12 may be activated integrally.

  In the activation devices 20, 40, 50, 60, oxygen is substantially evenly supplied to the power generation cells 12 at each stage of the cell stack 10 </ b> S. For this reason, in the power generation cell 12, an abnormal polarization phenomenon due to oxygen supply is unlikely to occur.

  Therefore, as long as the membrane electrode assembly 12M can be kept wet, when the constant voltage load 21 and the DC power supply 26 are connected using the extraction electrodes 18A and 18b, the reversal as shown in FIG. Does not occur. The phenomenon that the fuel cell deteriorates due to the inversion is also less likely to occur.

  Further, the atmosphere in the fuel diffusion electrode 15 and the oxygen diffusion electrode 14 during the activation process may be hydrogen and air (or oxygen), respectively, in the power generation state in the normal operation of the fuel cell 10, and may be nitrogen or the like. An inert gas atmosphere may be used. Further, the fuel main flow path 13A may be in a state where the outlet is closed or in an open state.

  Further, the driving assistance mechanism 30 described in the first to fourth embodiments handles not only the fuel cell 10 including the cell stack 10S in which a plurality of power generation cells 12 are connected in series, but also the power generation cell 12 alone. It is also effective for fuel cells.

  In addition, the small fuel cell often closes the outlet of the fuel supply path and supplies only the consumed amount of fuel. However, the activation method of the present invention opens the outlet of the fuel flow path by a predetermined amount and supplies the fuel. It is preferable to carry out in a state where more than the consumption is supplied.

<Sixth Embodiment>
FIG. 18 is an explanatory diagram of the configuration of the fuel cell mounted on the activation device of the sixth embodiment, and FIG. 19 is an explanatory diagram of the configuration of the activation device of the sixth embodiment. The activation apparatus of 1st Embodiment-5th Embodiment demonstrated activation of the fuel cell which piled up several power generation cells and connected in series. On the other hand, the activation device 70 of the sixth embodiment improves the power generation performance at the time of activation by mounting and activating the fuel cell 110 in which a plurality of power generation cells 112 are arranged in a plane.

  As shown in FIG. 18, the plurality of power generation cells 112 arranged in a plane are connected in parallel by a common fuel electrode current collector 117 and an oxygen electrode current collector 116 to extract power in parallel. In the power generation cell 112, the fuel diffusion electrode 115 is brought into contact with one surface of the membrane electrode assembly 112M, and the oxygen diffusion electrode 114 is brought into contact with the other surface. The membrane / electrode assembly 112M has catalyst layers formed on both sides of the polymer electrolyte membrane.

  The fuel diffusion electrode 115 and the oxygen diffusion electrode 114 are housed in independent openings of the fuel electrode spacer 103 and the oxygen electrode spacer 104, respectively. The fuel electrode spacer 103 and the oxygen electrode spacer 104 are assembled together with the power generation cell 112 by being sandwiched between the fuel electrode current collector 117 and the oxygen electrode current collector 116.

  In the fuel electrode current collector 117 and the oxygen electrode current collector 116, a conductive porous material is disposed independently for each power generation cell 112, and hydrogen gas and oxygen do not diffuse between adjacent power generation cells 112, respectively. It is like that. The hydrogen gas is supplied to the power generation cell 112 through the flow path substrate 102 disposed on the lower surface of the fuel electrode current collector 117. A space surrounded by the partition frame of the fuel electrode current collector 117 and the fuel electrode spacer 103, the membrane electrode connector 112M, and the flow path substrate 102 accommodates the fuel electrode diffusion electrode 115 and is sealed from the outside air. It is a space.

  The oxygen diffusion electrode 114 is housed in the partition frame of the oxygen electrode spacer 104 and has a surface open to the atmosphere through the oxygen electrode current collector 116. In the fuel cell 110, since the power generation cells 112 are arranged in a plane, the oxygen intake area and the water vapor discharge area can be widely secured as compared with the type stacked on the cell stack 10S shown in FIG.

  A flow path 106 for distributing hydrogen gas to the plurality of power generation cells 112 is formed in the flow path substrate 102. The portion of the flow path 106 that is in contact with the fuel electrode current collector 117 is formed shallow to increase the flow path resistance, so that hydrogen gas does not pass therethrough. Hydrogen gas taken out from a fuel tank (not shown) and adjusted to a pressure slightly higher than the atmospheric pressure is supplied to the flow channel 106, and is supplied from the flow channel 1-6 to the fuel diffusion electrode 115 through the fuel electrode current collector 117. Flows in.

  In the catalyst layer of the membrane electrode assembly 112M in contact with the fuel diffusion electrode 115, the hydrogen gas is decomposed and ionized by the catalytic reaction to supply hydrogen ions to the polymer electrolyte membrane. In the catalyst layer of the membrane electrode assembly 112M in contact with the oxygen diffusion electrode 114, oxygen combines with hydrogen ions picked up from the polymer electrolyte membrane by a catalytic reaction to generate water molecules. The polymer electrolyte membrane of the membrane electrode assembly 112M moves hydrogen ions from the fuel diffusion electrode 115 side to the oxygen diffusion electrode 114 side.

  As shown in FIG. 19, in the activation device 70 of the sixth embodiment, the fuel cell 110 is fitted into a recess formed on the upper surface of the main body 70A, and the fuel cell 110 is pressed and fixed to the main body 70A by the pressing plate 70B. To do. Simultaneously with the fixing, the flow path 106 of the fuel cell 110 is positioned and connected to the hydrogen gas supply unit on the main body 70A side, and the extraction electrodes 118A and 118B are connected to the constant voltage load 21.

  The hydrogen gas taken out from the fuel tank 71 that stores the hydrogen gas is supplied through the water retention space 72 to the hydrogen gas supply unit on the main body 70 </ b> A side. The water retention space 72 is a sealed space in which water can be supplied from the outside, and includes a heater 73 on the outside. The water supplied to the water retention space 72 is heated and evaporated by the heater 73 to humidify the hydrogen gas.

  As in the first embodiment, the fuel cell 110 is attached to the activation device 70, and the constant voltage load 21 is operated while supplying humidified hydrogen gas. The wetness of the membrane electrode assembly 112M in the dry initial state is rapidly increased by forcibly outputting a current much larger than a normal current that is taken out and attached to the device for a short time (within 1 minute). Increase. As a result, the power generation performance of the fuel cell 110 is quickly recovered, and when the fuel cell 110 is taken out from the activation device 70 and attached to the device, a large current can be immediately output with a high electromotive force.

<Seventh embodiment>
In the first to sixth embodiments, the fuel cells 10 and 110 before being attached to the device are attached to the single activation devices 20, 40, 50, 60 and 70 and activated. However, after the fuel cells 10 and 110 are assembled in the manufacturing process of the fuel cells 10 and 110, they are mounted on the activation devices 20, 40, 50, 60, and 70 so that the current much lower than the low current is shortened. The power generation performance of the fuel cells 10 and 110 may be improved by forcibly outputting the time. Thereafter, the fuel cells 10 and 110 are steam-packed so that the fuel cells 10 and 110 taken out of the pack and attached to the device can immediately output a large current with a high electromotive force.

<Activation device of comparative example>
Conventionally, various primary batteries and secondary batteries have been used to carry and use small electric devices. However, with recent high performance of small electric devices, power consumption has increased, and primary batteries are small and light and cannot supply sufficient energy. On the other hand, although the secondary battery has an advantage that it can be repeatedly charged and used, the energy that can be used in one charge is much less than that of the primary battery. In order to charge the secondary battery, a separate power source is required, and charging usually takes several tens of minutes to several hours, and it is difficult to immediately use it anytime and anywhere. . In the future, as electric devices become increasingly smaller and lighter, and the wireless network environment is in place, the tendency to carry and use devices will increase. Conventional primary and secondary batteries are sufficient to drive devices. It is difficult to supply a large amount of energy.

  As a solution to such a problem, a small fuel cell has attracted attention. Conventionally, fuel cells have been developed as a drive source for large generators and automobiles. This is mainly because the fuel cell has higher power generation efficiency and clean waste than the conventional power generation system. On the other hand, the reason why fuel cells are useful as a drive source for small electric devices is that the amount of energy that can be supplied per volume and per weight is several to ten times that of conventional batteries. Furthermore, since it can be used continuously if only the fuel is replaced, it does not take time to charge unlike other secondary batteries.

  Although various types of fuel cells have been invented, a fuel cell using a polymer electrolyte membrane is suitable for small electric devices, particularly devices that are carried and used. This is because it can be used at a temperature close to room temperature, and since the electrolyte is a solid rather than a liquid, it has the advantage of being safe to carry.

  A membrane electrode assembly, which is a reaction field for power generation of a fuel cell using a polymer electrolyte membrane, has a structure in which catalyst layers are arranged on both sides of the polymer electrolyte membrane. The catalyst layer is composed of a mixture of a catalyst and an electrolyte. Further, various substances may be added to the catalyst layer in order to impart water repellency and conductivity. The membrane electrode assembly is sandwiched between porous electrodes to form a power generation cell. In the power generation cell, a fuel (hydrogen) is supplied to the fuel diffusion electrode and an oxidizing agent (oxygen or air) is supplied to the oxygen diffusion electrode. At that time, water is generated as a product. The reaction formulas at the fuel diffusion electrode and the oxygen diffusion electrode are as follows.

Fuel diffusion electrode

Oxygen diffusion electrode

  Protons generated at the fuel diffusion electrode pass through the polymer electrolyte membrane to the oxygen diffusion electrode, and react with oxygen and electrons in the catalyst layer on the oxygen diffusion electrode side to generate water. Protons travel through cluster portions filled with water in the electrolyte of the polymer electrolyte membrane, the fuel diffusion electrode, and the oxygen diffusion electrode. Therefore, at the time of power generation, the electrolyte of the polymer electrolyte membrane, the fuel diffusion electrode, and the oxygen diffusion electrode needs to be sufficiently hydrated. As a result, the ion conduction resistance is reduced, and protons easily reach the catalyst surface, thereby increasing the number of reaction sites in effect and improving the output characteristics of the fuel cell.

  In particular, after production, a membrane electrode assembly that has not yet generated electricity often has a reduced moisture content due to the production process. In addition, the shape of the cluster that conducts protons is not optimized. Such a membrane electrode assembly in a low activity state is activated by generating power with a current of a certain amount or more, so that the electrolyte membrane contains water and the cluster structure is optimized. The reaction of the polymer electrolyte fuel cell is particularly activated at about 80 ° C.

  Therefore, Patent Document 1 discloses a fuel cell starting method and manufacturing method that can be quickly started at a high battery output by conditioning the polymer electrolyte fuel cell before making it into a power generation state. . Conditioning means that a fuel cell is connected to an external circuit, and a current having a current density higher than a set value of a predetermined output current density required based on an external load request is passed through the fuel cell and the external circuit in advance during power generation. It is.

  Further, in Patent Document 2, when the fuel cell is started, the output voltage of the fuel cell is detected, and if it is determined that a sufficient output voltage is not obtained and the fuel cell is not in the rated operation state, Switch the connection from external output to impedance. Thus, a method is disclosed in which the fuel cell is heated by power generation and the state shifts to a rated operation enabled state.

  As a method of operating the fuel cell at a high output, there is a method of forcibly supplying air by a blower or the like. For example, Patent Document 3 discloses means for forcibly supplying air to a fuel cell at the time of rated power generation of the fuel cell. Further, Patent Document 4 discloses a fuel cell system in which a blower mechanism is provided not in the fuel cell body but in a device in which the fuel cell is mounted.

By the way, when a voltage is applied between both electrodes in a state where water is supplied to the power generation cell, electrolysis of water occurs due to a reaction opposite to that of the fuel cell. That is, when electricity is applied between the anode and the cathode, oxygen is generated in the cathode catalyst layer, and hydrogen is generated in the anode catalyst layer. Water electrolysis using a polymer electrolyte membrane has a high energy efficiency of 90% and a high current density of 1 to 3 A / cm ² , so it has been put to practical use as a compact and highly efficient hydrogen generator. . Furthermore, since the polymer electrolyte membrane is solid and the reaction temperature is several tens of degrees Celsius, it has the advantage of being easy and safe.

  However, in many cases, a fuel cell mounted on a small electric device does not use a humidifier, a heater, a pump, a blower, or the like in order to reduce the size of the system. In such a fuel cell, humidification is performed by water generated during power generation, and heating is performed by generated heat. The air necessary for the reaction is taken in by natural diffusion. Even if conventional activation / startup methods are used for such fuel cells, the amount of fuel and air that can be taken in is limited, and the resistance of the initial electrolyte is large, so the operating temperature and water content of the electrolyte It was difficult to obtain sufficient output to raise the state to the optimum state.

  In particular, in the case of using a plurality of power generation cells connected in series, operation in a state close to the power generation performance limit of the fuel cell forcibly applies the voltage of another fuel cell to one set of fuel cells. A reversal phenomenon occurs. When the reversal phenomenon occurs, the system becomes very unstable and may cause deterioration of the fuel cell. In addition, a blower or the like is sometimes mounted on a fuel cell for a small electric device, but this is used to increase the output at the rated output, and cannot be removed while the fuel cell is in use. Such pumps and blowers may increase the size of the system during use.

  In contrast, in the first to sixth embodiments, the activation device has an external load mechanism and a driving assistance mechanism, so that the ion conduction resistance of the polymer electrolyte membrane is sufficiently lowered. Can do. Therefore, the polymer electrolyte fuel cell can be operated at a high output. In addition, a high output fuel cell can be manufactured.

<Correspondence with Invention>
The activation device 20 of the first embodiment improves the startup characteristics of the fuel cell 10 including the membrane electrode assembly 12M. A holding mechanism 20A that detachably holds the fuel cell 10, a constant voltage load 21 that is connected to the fuel cell 10 held by the holding mechanism 20A, extracts current from the fuel cell 10 and continues power generation, and a membrane electrode joint And a driving assistance mechanism 30 that activates the power generation function of the body 12M. Then, by operating the constant voltage load 21 in a state where the driving assist mechanism 30 is operated, power generation based on a current-voltage condition that is impossible in the membrane electrode assembly 12M in the initial state where the driving assist mechanism 30 is not operated is forced. .

  In the first embodiment, since the fuel cell 10 is attached to the activation device 20 before being loaded into the device and the startup characteristics of the fuel cell 10 are enhanced, the fuel cell 10 is loaded when the fuel cell 10 is loaded into the device. High electromotive force can be output immediately.

  Further, since the activation device 10 is a device that is independent from both the device and the fuel cell 10, it is possible to perform design with the highest priority on function by ignoring the incorporation into the fuel cell 10 or the device. Since neither the fuel cell 10 nor the device is built in, the fuel cell 10 or the device is not increased in size, increased in parts, or increased in cost due to the activation device 20.

  In addition, the constant voltage load 21 (DC power supply 26) and the driving assist mechanism 30 can be selected with the highest priority given to the improvement of the startup characteristics of the fuel cell 10 without depending on the output of the fuel cell 10 in the initial state. The start-up characteristics of the fuel cell 10 can be improved in a very short time while securing the safety factor. In other words, through the current more than short-circuited by applying a voltage of the opposite polarity to the power generation from the outside to the power generation cell 12, or by detecting the state of each power generation cell 12 of the fuel cell 10 using the microcomputer control device, It is also possible to control the driving state and driving assistance state.

  The fuel cell 10 includes an oxygen diffusion electrode 14 that diffuses oxygen in the atmosphere on one surface side of the membrane electrode assembly 12M, and the operation assist mechanism 30 of the activation device 50 of the third embodiment includes the oxygen diffusion electrode 14. The blower 25 forcibly sends air to the air.

  The fuel cell 10 includes an oxygen diffusion electrode 14 for diffusing oxygen in the atmosphere on one surface side of the membrane electrode assembly 12M, and a fuel diffusion electrode 15 for supplying hydrogen gas to the other surface side of the membrane electrode assembly 12M. Is provided. The driving assistance mechanism 30 of the first embodiment is a humidifier 22 (or a water supply device 23) that forcibly diffuses moisture into at least one of the oxygen diffusion electrode 14 and the fuel diffusion electrode 15.

  The activation device 40 of the second embodiment includes a heater 24 that heats the fuel cell 10 from the outside.

  The activation device 20 of the first embodiment takes out an excessive current that is impossible with the membrane electrode assembly 12M in the initial state in which the operation assisting mechanism 30 is not operated while keeping the voltage generated by the membrane electrode assembly 12M constant. The constant voltage load 21 which continues is provided.

  The activation device 60 according to the fourth embodiment applies a voltage having a polarity opposite to the voltage generated by the membrane electrode assembly 12M to the membrane electrode assembly 12M, and generates a current from the fuel cell 10 that is short-circuited from the power generation output. A DC power supply 26 that continues to be taken out is provided.

  The direct current power source 26 is a constant current power source that continuously takes out an excessively constant current that is impossible with the membrane electrode assembly 12M in the initial state in which the driving assist assist mechanism 30 is not operated by changing the voltage of reverse polarity.

  In the fuel cell manufacturing method of the seventh embodiment, after assembling the fuel cell 10 including the membrane electrode assembly 12M, the fuel cell 10 is attached to any of the activation devices 20, 40, 50, 60, and the membrane electrode assembly 12M is attached. Force the power generation at a current that is larger than the current that can be output in the initial state. Thereby, the starting characteristic of the fuel cell 10 is improved.

  The activation device 20 according to the first embodiment is mounted immediately before the fuel cell 10 including the membrane electrode assembly 12M is mounted on a device, and the membrane electrode assembly 12M is more than the current value that can be output in the initial state. Force power generation with excessive current. Thereby, the starting characteristic of the fuel cell 10 in an apparatus is improved.

It is a perspective view explaining the structure of the activation apparatus of 1st Embodiment. It is explanatory drawing of the state which connected the fuel cell to load. It is a diagram of the starting characteristic of the fuel cell in the initial state. It is a schematic diagram of the state which mounted | wore the activation apparatus with the fuel cell. It is explanatory drawing of the activation apparatus which humidifies hydrogen gas using a humidifier. It is a diagram explaining the activation by humidification. It is explanatory drawing of the activation apparatus which supplies water to an oxygen diffusion electrode using a water feeder. It is a diagram explaining the activation by water supply. It is a diagram which compares the activation process by humidification and water supply. It is explanatory drawing of a structure of the activation apparatus which performs heater heating. It is explanatory drawing of a structure of the activation apparatus of 2nd Embodiment. It is explanatory drawing of a structure of the activation apparatus of 3rd Embodiment. It is the diagram which compared the electric power generation performance with the case where it does not use the case where a blower is used. It is explanatory drawing of the structure of the activation apparatus of 4th Embodiment. It is explanatory drawing of the structure which used together the DC power supply and the water feeder as a driving assistance mechanism. It is a diagram explaining the activation effect which used DC power supply and water supply together. It is explanatory drawing of the inversion phenomenon in the power generation cell of a cell stack. It is explanatory drawing of a structure of the fuel cell with which the activation apparatus of 6th Embodiment is mounted | worn. It is explanatory drawing of the structure of the activation apparatus of 6th Embodiment.

Explanation of symbols

10, 110 Fuel cell 11 Air intake 12 Power generation cell 12M Polymer electrolyte layer (membrane electrode assembly)
13A Fuel main flow path 13B Water supply main flow path 14 Oxygen diffusion electrode 15 Fuel diffusion electrode 16 Oxygen electrode current collector 17 Fuel electrode current collectors 18A, 18B Extraction electrodes 19A, 19B Pressure plates 20, 40, 50, 60, 70 Activation device 20A , 20B, 20D, 20E Holding means (holding mechanism, fuel supply connector, connection electrode)
20C Water supply connector 21, 26 Operation means (constant voltage load, DC power supply)
22, 23 Humidification means (humidifier, water supply)
24 Heating means (heater)
25 Air supply means (blower)
30 Driving assistance means (driving assistance mechanism)

Claims (9)

An activation device for improving the starting characteristics of a fuel cell having a polymer electrolyte layer,
Holding means for holding the fuel cell detachably and enabling operation;
An operating means connected to the power generation cell of the fuel cell held by the holding means, and for causing a current to flow to the fuel cell;
Driving assistance means for activating the power generation function of the polymer electrolyte layer,
By operating the driving means in a state where the driving auxiliary means is operated, power generation based on a current-voltage condition impossible in the polymer electrolyte layer in an initial state where the driving auxiliary means is not operated is forced. An activation device. The fuel cell includes an oxygen diffusion space for diffusing oxygen in the atmosphere on one surface side of the polymer electrolyte layer,
2. The activation apparatus according to claim 1, wherein the operation assisting means is air supply means for forcibly sending air into the oxygen diffusion space. The fuel cell is disposed on one side of the polymer electrolyte layer to diffuse oxygen in the atmosphere, and is disposed on the other side of the polymer electrolyte layer to supply hydrogen gas. A hydrogen gas supply space,
3. The activation according to claim 1, wherein the operation assisting means is a humidifying means for forcibly diffusing moisture into at least one of the oxygen diffusion space and the hydrogen gas supply space. apparatus.   4. The activation apparatus according to claim 3, further comprising heating means for heating the fuel cell from the outside.   The operation means includes an electrical load that keeps taking out an excessive current that is impossible in the polymer electrolyte layer in an initial state in which the voltage to be generated in the polymer electrolyte layer is kept constant and the operation auxiliary means is not operated. The activation device according to any one of claims 1 to 4, wherein   The operating means includes voltage applying means for applying a voltage having a reverse polarity to the voltage generated by the polymer electrolyte layer to the polymer electrolyte layer, and continuously taking out a current of a rated current or more from the fuel cell. The activation device according to any one of claims 1 to 4, characterized in that:   The voltage application means is a constant current power source that continues to take out an excessively constant current that is impossible in the polymer electrolyte layer in an initial state in which the driving assistance means is not operated by changing the voltage of reverse polarity. The activation device according to claim 6.   After assembling the fuel cell including the polymer electrolyte layer, the fuel cell is mounted on the activation device according to any one of claims 1 to 7, and the polymer electrolyte layer is larger than a current value that can be output in an initial state. A method for manufacturing a fuel cell, comprising: forcing power generation with current to improve the start-up characteristics of the fuel cell. The current value that can be output in the initial state when the polymer electrolyte layer is attached to the activation device according to any one of claims 1 to 7, immediately before the fuel cell including the polymer electrolyte layer is attached to the device. A method of using a fuel cell, wherein the starting characteristics of the fuel cell in the device are improved by forcing power generation with an excessive current.

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