JP5742394B2 - Aging method for polymer electrolyte fuel cell and power generation system for polymer electrolyte fuel cell - Google Patents

Description

  The present invention relates to an aging method for a polymer electrolyte fuel cell and a power generation system for the polymer electrolyte fuel cell.

  In a polymer electrolyte fuel cell, electrodes comprising a catalyst layer and a conductive porous substrate are formed on both surfaces of an ion conductive polymer electrolyte membrane, and a gasket is disposed so as to surround the electrode, It has a structure sandwiched between separators. This polymer electrolyte fuel cell generates power by supplying fuel to one electrode (fuel electrode) and supplying an oxidant to the other electrode (air electrode). Hydrogen is generally used as the fuel, but an alcohol aqueous solution such as methanol or ethanol can also be used, and those using an alcohol aqueous solution as the fuel are called direct liquid fuel cells (Patent Documents 1 and 2). reference).

  This direct liquid fuel cell includes a cation type in which hydrogen ions generated in the fuel electrode move in the ion conductive polymer electrolyte membrane, and a hydroxide ion generated in the fuel electrode in the ion conductive polymer electrolyte membrane. It is classified as an anion type that moves inside. In the case of a cation type direct liquid fuel cell, it is known that a high output can be obtained by adding a proton exchange resin such as Nafion as a binder to the electrode to improve the hydrogen ion conductivity of the electrode. On the other hand, in the case of an anion-type direct liquid fuel cell, since there is no effective binder for increasing the hydroxide ion conductivity of the electrode, an alkaline substance such as sodium hydroxide or potassium hydroxide is added to the alcohol aqueous solution as the fuel. In this way, the hydroxide ion conductivity is increased and the output is improved.

JP 2008-210718A JP 2010-176848 A

  By the way, the anion type direct liquid fuel cell as described above is subjected to aging in order to ensure a predetermined output characteristic before use. In this aging, an alcohol aqueous solution having the same alkaline substance content as that at the time of use is supplied to the fuel electrode, but the internal resistance is not sufficiently lowered, and it is difficult to obtain a predetermined output in the initial use. There was a problem.

  Therefore, an object of the present invention is to provide an aging method for a polymer electrolyte fuel cell and an electric power generation system for the polymer electrolyte fuel cell that can reliably reduce the internal resistance.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors first supplied a fuel having an alkaline substance content of 3 wt% or less in aging of the polymer electrolyte fuel cell to reduce the load current. It has been found that the internal resistance of the polymer electrolyte fuel cell is lowered by flowing, and the present invention has been completed. That is, an aging method for a polymer electrolyte fuel cell according to the present invention provides an ion conductive polymer electrolyte membrane and a polymer electrolyte fuel cell having electrodes formed on both sides of the ion conductive polymer electrolyte membrane. A step of supplying a first fuel containing alcohol and an alkaline substance content of 3% by weight or less to one electrode of the polymer electrolyte fuel cell; and supplying the first fuel And a step of supplying a load current to the solid polymer fuel cell, and a step of supplying a second fuel containing an alcohol and an alkaline substance to the one electrode after supplying the load current. .

  In the above aging method, the alkaline substance contained in the second fuel is not particularly limited as long as it has hydroxide ion conductivity, but examples thereof include potassium hydroxide, sodium hydroxide, or ammonia. Can do.

  In the above aging method, a load current is supplied to the polymer electrolyte fuel cell supplied with the first fuel for 5 seconds or more, and then the second fuel is supplied to one electrode (fuel electrode). Can do.

  A power generation system for a first polymer electrolyte fuel cell according to the present invention includes an ion conductive polymer electrolyte membrane and a polymer electrolyte fuel cell having electrodes formed on both sides of the ion conductive polymer electrolyte membrane. A system for generating power, the first storage tank for storing a first fuel containing alcohol and having an alkaline substance content of 3% by weight or less, and a second tank containing alcohol and an alkaline substance A second storage tank that stores the first fuel in the first storage tank or a second storage tank in the second storage tank with respect to one electrode of the polymer electrolyte fuel cell A supply line for selectively supplying fuel; an oxidant supply means for supplying an oxidant to the other electrode of the polymer electrolyte fuel cell; and a load current electrically connected to the polymer electrolyte fuel cell Negative It is provided with a means, a.

  In the power generation system of the first polymer electrolyte fuel cell, first, a first polymer containing alcohol and having an alkaline substance content of 3% by weight or less is supplied from the first storage tank to the polymer electrolyte. Supply to the fuel cell. Then, after a load current is passed to the polymer electrolyte fuel cell by the load means, the second fuel containing alcohol and an alkaline substance is supplied from the second storage tank to the polymer electrolyte fuel cell, thereby aging. Therefore, the internal resistance of the polymer electrolyte fuel cell can be sufficiently reduced. Further, if the second fuel is continuously supplied to the polymer electrolyte fuel cell after the aging is completed, the polymer electrolyte fuel cell can be used as it is.

  The power generation system may further include a voltmeter that measures a voltage applied to the polymer electrolyte fuel cell. According to this configuration, the magnitude of the load current can be adjusted according to the magnitude of the voltage applied to the polymer electrolyte fuel cell.

  When the said power generation system is provided with the voltmeter, it is preferable to further provide the control means which controls the magnitude | size of the load current by a load means based on the voltage measured by this voltmeter.

  The power generation system can further include a third storage tank in which water is stored. In this case, the supply line selectively supplies the first fuel in the first storage tank, the second fuel in the second storage tank, or the water in the third storage tank to one electrode. It is configured as follows. According to this configuration, after using the polymer electrolyte fuel cell, water is supplied from the third storage tank to the polymer electrolyte fuel cell, and the first and second remaining in the polymer electrolyte fuel cell are supplied. Since the fuel can be removed, deterioration of the polymer electrolyte fuel cell can be prevented. In addition, if water is supplied to the polymer electrolyte fuel cell after use and the ion conductive polymer electrolyte membrane and electrode are kept moist, the next time the polymer electrolyte fuel cell is used. There is no need to perform aging again.

  The second power generation system of the polymer electrolyte fuel cell according to the present invention includes an ion conductive polymer electrolyte membrane and a polymer electrolyte fuel having electrodes formed on both surfaces of the ion conductive polymer electrolyte membrane. A system for generating power by a battery, comprising a first storage tank for storing a first fuel containing alcohol and containing 3% by weight or less of an alkaline substance, and containing alcohol and an alkaline substance A second storage tank for storing a second fuel, a receiving tank that is selectively attached to the first and second storage tanks, and that selectively communicates with the first or second storage tank; A supply line for supplying the first or second fuel in the receiving tank to one electrode of the polymer electrolyte fuel cell; and an oxidant supply means for supplying an oxidant to the other electrode of the polymer electrolyte fuel cell; , Solid It includes a load means to flow a load current is electrically connected to the polymer electrolyte fuel cell, a.

  In the second polymer electrolyte fuel cell power generation system, the first fuel is supplied from the first storage tank to the polymer electrolyte fuel cell via the receiving tank, and a load current is supplied by the load means. After that, since the aging can be performed by supplying the second fuel from the second storage tank through the receiving tank, the internal resistance of the polymer electrolyte fuel cell can be sufficiently reduced. Similarly to the power generation system of the first polymer electrolyte fuel cell, if the second fuel is continuously supplied to the polymer electrolyte fuel cell after the aging is completed, the polymer electrolyte fuel cell can be used as it is. it can.

  The power generation system may further include a voltmeter that measures a voltage applied to the polymer electrolyte fuel cell. According to this configuration, the magnitude of the load current can be adjusted according to the magnitude of the voltage applied to the polymer electrolyte fuel cell.

  When the said power generation system is provided with the voltmeter, it is preferable to further provide the control means which controls the magnitude | size of the load current by a load means based on the voltage measured by this voltmeter.

  The power generation system can further include a third storage tank in which water is stored. In this case, the receiving tank is configured to selectively communicate with any of the first to third storage tanks. After using the polymer electrolyte fuel cell, water is supplied from the third storage tank to the polymer electrolyte fuel cell via the receiving tank, and the first and second fuels remaining in the polymer electrolyte fuel cell Therefore, it is possible to prevent deterioration of the polymer electrolyte fuel cell.

  According to the present invention, the internal resistance of the polymer electrolyte fuel cell can be reliably reduced.

1 is a power generation system for a polymer electrolyte fuel cell according to a first embodiment of the present invention. It is a power generation system of the polymer electrolyte fuel cell which concerns on the modification of the said 1st Embodiment. It is a power generation system of a polymer electrolyte fuel cell according to a second embodiment of the present invention. It is a graph which shows the output of the polymer electrolyte fuel cell which concerns on Example 1 and Comparative Example 1 of this invention. It is a graph which shows the output of the polymer electrolyte fuel cell which concerns on Example 2 and Comparative Example 2 of this invention. It is a graph which shows the output of the polymer electrolyte fuel cell which concerns on Example 1 and Comparative Example 1, and Example 3 and Comparative Example 3 of this invention.

(First embodiment)
First, a first embodiment of a power generation system for a polymer electrolyte fuel cell and an aging method for a polymer electrolyte fuel cell using the power generation system according to the present invention will be described with reference to FIG.

  As shown in FIG. 1, the first power generation system S1 of the polymer electrolyte fuel cell P according to the first embodiment has a first storage in which the first fuel is stored in the first power generation device D1. A tank 11, a second storage tank 12 that stores the second fuel, and a first supply line 13 that supplies fuel to the polymer electrolyte fuel cell P are provided. The first power generator D1 is also provided with an oxidant supply means 14 for supplying an oxidant to the polymer electrolyte fuel cell P and a load means 15 for supplying a load current to the polymer electrolyte fuel cell P. The magnitude of the load current by the load means 15 is controlled by the first control means C1 based on the magnitude of the voltage of the polymer electrolyte fuel cell P measured by the voltmeter V. Further, a resistance sensor S may be provided in the first power generator D1 so that the internal resistance of the polymer electrolyte fuel cell P can be monitored.

  The first and second storage tanks 11, 12 are connected to the polymer electrolyte fuel cell P via a first supply line 13, and a first supply installed in the first supply line 13. The first fuel in the first storage tank 11 or the second fuel in the second storage tank 12 is sent to the first electrode E1 of the polymer electrolyte fuel cell P by the pump 191. Note that the first supply pump 191 may not be installed in the first supply line 13 as long as each fuel can be sent to the first electrode E1 by gravity or the like. The first supply line 13 includes a first supply channel 131 that communicates with the first storage tank 11 and a second supply channel 132 that communicates with the second storage tank 12. A first switching cock 133 is provided at a portion where the one supply channel 131 and the second supply channel 132 merge. When the first supply channel 131 is opened and the second supply channel 132 is closed by the first switching cock 133, the first fuel in the first storage tank 11 is solid polymer fuel cell. When the first supply channel 131 is closed and the second supply channel 132 is opened, the second fuel in the second storage tank 12 is supplied as a solid polymer fuel. The battery P can be supplied. The selection of the supply flow path by the first switching cock 133 may be controlled by the first control means C1. That is, the first control means C1 issues an instruction to the first switching cock 133 when the load means 15 stops, and the first switching cock 133 switches the supply flow path based on this instruction.

  The first and second storage tanks 11 and 12 are connected to the polymer electrolyte fuel cell P through the first recovery line 16. The first recovery line 16 supplies the water generated in the polymer electrolyte fuel cell P and the first and second fuels remaining in the polymer electrolyte fuel cell P to the first and second storage tanks 11. , 12, and has a first recovery channel 161 that communicates with the first storage tank 11 and a second recovery channel 162 that communicates with the second storage tank 12. Yes. A second switching cock 163 similar to the first switching cock 133 is provided at a portion where the first recovery flow path 161 and the second recovery flow path 162 merge. This second switching cock The first or second recovery flow path 161, 162 is selectively opened by the cock 163. The second switching cock 163 is also preferably controlled by the first control means C1 so as to select the first or second recovery flow path 161, 162, similarly to the first switching cock 133. .

  A supplementary fuel storage tank 17 is provided outside the first power generation device D1, and supplementary fuel for supplementing the first and second storage tanks 11 and 12 is provided in the supplementary fuel storage tank 17. Reserved. The supplementary fuel storage tank 17 is connected to the first and second storage tanks 11 and 12 through a supplementary line 18, and supplementary fuel is supplied to the first and second storage tanks 11 through the supplementary line 18. , 12 is provided with a second supply pump 192 for delivery. The replenishment line 18 includes a first replenishment channel 181 that communicates with the first storage tank 11 and a second replenishment channel 182 that communicates with the second storage tank 12. The two replenishing channels 181 and 182 are selectively opened by a third switching cock 183 similar to the first switching cock 133. In the first power generation system S1, the supplementary fuel storage tank 17 can be omitted. In this case, the first and second storage tanks 11 and 12 may be supplemented directly with fuel.

  The first fuel in the first storage tank 11 is not limited as long as it contains alcohol and the content of the alkaline substance is 3% by weight or less, and the content of the alkaline substance is smaller than that of the second fuel. It is preferable. Although it does not specifically limit as alcohol, For example, ethanol, methanol, 1-propanol, or ethylene glycol etc. are mentioned. In the first fuel, alcohol is mixed in an appropriate dispersion medium such as water, and the molar concentration thereof is, for example, usually 0.1 to 10 mol / l, preferably 0.5 to 3 mol / l. Can do.

  The second fuel in the second storage tank 12 is a liquid containing alcohol and an alkaline substance, and is not particularly limited. For example, ethanol, methanol, 1-propanol, or ethylene glycol is used. Examples include alcohol mixed with an appropriate dispersion medium such as water and at least one alkaline substance such as potassium hydroxide, sodium hydroxide or ammonia added thereto. In the second fuel, the molar concentration of the alcohol can be usually 0.1 to 10 mol / l, preferably 0.5 to 3 mol / l, and the content of the alkaline substance is usually 1 to 1 mol, for example. In order to obtain a higher output of 10% by weight, preferably 5 to 10% by weight.

  As the supplementary fuel in the supplementary fuel storage tank 17, the first and second fuels in the first and second storage tanks 11 and 12 described above are consumed by the solid polymer fuel cell P, or the solid polymer. When diluted with water recovered from the fuel cell P, the first and second storage tanks 11 and 12 are replenished. The supplementary fuel is not particularly limited. For example, pure alcohol or a 10 to 30 mol / l high-concentration alcohol aqueous solution can be used. If necessary, an alkaline aqueous solution having a concentration of 10% by weight is used. You can also

  The oxidant supply means 14 supplies an oxidant such as oxygen to the second electrode E2 of the polymer electrolyte fuel cell P. As the oxidant supply means 14, for example, an air pump can be used. . The load means 15 is electrically connected to the polymer electrolyte fuel cell P, consumes electric power from the polymer electrolyte fuel cell P, and applies a load to the polymer electrolyte fuel cell P. As the means 15, for example, an electronic load device can be used.

  In the polymer electrolyte fuel cell P, first and second electrodes E1 and E2 made of a catalyst layer and a conductive porous substrate are formed on both surfaces of an ion conductive polymer electrolyte membrane M. Gaskets (not shown) are arranged so as to surround the electrodes E1 and E2, and these are sandwiched by separators (not shown). In this embodiment, in order to simplify the description, the polymer electrolyte fuel cell P is described as including one membrane-electrode assembly, but in actual use, a plurality of sheets are used. It goes without saying that the necessary voltage and output can be obtained by laminating (stacking structure) or arranging them in parallel (side-by-side structure).

  As the ion conductive polymer electrolyte membrane M, any one of hydrocarbon-based and fluororesin-based anion conductive solid polymer electrolyte membranes can be used. More specifically, as the hydrocarbon-based anion conductive solid polymer electrolyte membrane, for example, Aciplex (registered trademark) A-201, 211, 221 manufactured by Asahi Kasei Corporation, Tokuyama Corporation Neoceptor (registered trademark) AM-1, AHA and the like can be mentioned. Examples of the fluororesin-based anion conductive solid polymer electrolyte membrane include Tosflex (registered trademark) IE-SF34 manufactured by Tosoh Corporation. Examples include Fumapem (registered trademark) FAA manufactured by FuMatech. When a high-concentration alkaline aqueous solution is used for the fuel, it is preferable to use a high-concentration alkaline-resistant fluororesin-based anion conductive solid polymer electrolyte membrane. From the viewpoint of cost, it is preferable to use hydrocarbon-based anion conductivity, but these can be appropriately selected depending on the system to be applied. In the alkaline aqueous solution, although it varies depending on the type of the alkaline aqueous solution, the high concentration usually means about 2 mol / l or more, and the low concentration means less than about 2 mol / l.

  The catalyst layers included in the first and second electrodes E1 and E2 can be known catalyst layers (cathode catalyst and anode catalyst), specifically, carbon particles supporting catalyst particles and ion conduction. Contains a functional polymer electrolyte. As the ion conductive polymer electrolyte, the same material as that used for the ion conductive polymer electrolyte membrane M can be used. The catalyst particles used for the cathode catalyst are not particularly limited as long as they are substances that promote the cathode reaction in the fuel cell. Iron, silver, etc. can be mentioned, and examples of the platinum compound include an alloy of platinum and at least one of the metals other than platinum described above. Examples of the catalyst particles used for the anode catalyst include platinum, an alloy of platinum and a metal other than platinum, or palladium. The carbon particles are not particularly limited as long as they have electrical conductivity, and known or commercially available ones can be widely used. For example, one or two types of carbon black, graphite, activated carbon, carbon nanotube, and the like can be used. The above can be used. Examples of carbon black include channel black, furnace black, ketjen black, acetylene black, and lamp black. The arithmetic average particle size of the carbon particles is usually about 5 nm to 200 nm, preferably about 20 to 80 nm, and can be measured by a particle size distribution measuring device LA-920: manufactured by Horiba, Ltd.

  As the conductive porous substrate included in the first and second electrodes E1 and E2, a known conductive porous substrate constituting the fuel electrode and the air electrode can be used, and the fuel and oxidant are efficiently catalyzed. In order to supply to the layer, it consists of a porous conductive substrate. Examples of the porous conductive substrate include carbon paper and carbon cloth.

  As the gasket (not shown), it is preferable to have a gas barrier property that is strong enough to withstand hot pressing and does not leak fuel and oxidant to the outside. For example, a polyethylene terephthalate sheet or Teflon (registered trademark) ) Sheet, silicon rubber sheet and the like.

  The separator (not shown) may be a conductive plate that is stable even in the environment inside the polymer electrolyte fuel cell P. Generally, a carbon plate formed with a gas flow path is used. Also, the surface of a metal such as stainless steel with a coating made of a conductive material such as chromium, platinum group metal or oxide thereof, or a conductive polymer, or the composite oxidation of silver or platinum group on the surface of a metal such as stainless steel. Further, a material plated with a material such as chromium nitride can be used as the separator.

  Next, a method of using the first power generation system S1 as described above will be described.

  First, the polymer electrolyte fuel cell P is mounted in the apparatus D1, and in order to ensure predetermined output characteristics of the polymer electrolyte fuel cell P, aging is performed as follows.

  After setting the temperature in the apparatus D1 to be, for example, 20 to 80 ° C., the first supply passage 131 is opened by the first switching cock 133 and the first fuel in the first storage tank 11 is opened. Is supplied to the first electrode E1 and the oxidizing agent supply means 14 supplies the oxidizing agent to the second electrode E2. The supply flow rate of the first fuel can be, for example, usually 0.1 to 10 ml / min, preferably 0.5 to 2 ml / min, and the supply flow rate of the oxidant is, for example, usually 50 to 1000 ml / min. , Preferably, it can be 100-200 ml / min.

  The supply of the first fuel and the oxidant is usually continued for 10 to 120 minutes, preferably 30 to 60 minutes, and then the first fuel and the oxidant are supplied to the polymer electrolyte fuel cell P while being loaded. 15 is driven and a load is applied to the polymer electrolyte fuel cell P. The load current at this time is not particularly limited, but is usually adjusted so that the voltage of the polymer electrolyte fuel cell P is 0.01 to 0.2 V, preferably 0.01 to 0.1 V. The It is preferable that a load is periodically applied to the polymer electrolyte fuel cell P. In this case, for example, after the load unit 15 is continuously driven for 5 seconds to 30 minutes, the load unit 15 is stopped for 5 to 60 minutes. The driving and stopping may be repeated 2 to 10 times. The water generated in the polymer electrolyte fuel cell P and the excess first fuel remaining in the polymer electrolyte fuel cell P are transferred to the first storage tank 11 via the first recovery line 16. To be recovered.

  As described above, when a load is applied to the polymer electrolyte fuel cell P, the internal resistance of the polymer electrolyte fuel cell P decreases. When the application of the load current is completed, the first supply channel 131 is closed and the second supply channel 132 is opened by the first switching cock 133. As a result, the supply of the first fuel to the first electrode E1 is stopped, and the supply of the second fuel in the second storage tank 12 is started. Note that the oxidizing agent continues to be supplied to the second electrode E2 by the oxidizing agent supply means 14. The supply flow rate of the second fuel is, for example, usually 0.1 to 10 ml / min, preferably 0.5 to 2 ml / min. Further, the supply time of the second fuel is not particularly limited, but is usually 10 to 180 minutes, preferably 30 to 90 minutes. The water generated in the polymer electrolyte fuel cell P and the excess second fuel remaining in the polymer electrolyte fuel cell P are transferred to the second storage tank 12 via the first recovery line 16. To be recovered.

  By supplying the second fuel, the internal resistance of the polymer electrolyte fuel cell P is further lowered and stabilized. Thus, when the internal resistance of the polymer electrolyte fuel cell P is stabilized, it is determined that the aging of the polymer electrolyte fuel cell P has been completed.

  Thus, the polymer electrolyte fuel cell P can be used by continuing to supply the second fuel and the oxidant to the polymer electrolyte fuel cell P that has been aged. When the use of the polymer electrolyte fuel cell P is finished, the second fuel already supplied to the polymer electrolyte fuel cell P is completely consumed in order to prevent deterioration of the polymer electrolyte fuel cell P. Is preferred.

  As described above, in the first embodiment, after supplying the first fuel having a content of alkaline substance of 3% by weight or less to the polymer electrolyte fuel cell P and supplying a load current, Since aging is performed by supplying the second fuel to which the substance is added, the internal resistance of the polymer electrolyte fuel cell P can be reliably reduced. In the first embodiment, the aging is performed while supplying the oxidant to the second electrode E2. However, the oxidant may not be supplied to the second electrode E2 during the aging.

  In the first embodiment, the water generated in the polymer electrolyte fuel cell P and the first and second fuels remaining in the polymer electrolyte fuel cell P are stored in the first or second reservoir. Although it was selectively collected in the tanks 11 and 12, it can be configured to be collected only in the second storage tank 12. In this case, the first supply channel 161 and the second switching cock 163 are unnecessary.

  Moreover, in the said 1st Embodiment, as shown in FIG. 2, the 3rd storage tank 101 in which water is stored can also be provided in 1st electric power generating apparatus D1. Thus, after the operation of the polymer electrolyte fuel cell P is completed, water is supplied from the third storage tank 101 to the first electrode E1 of the polymer electrolyte fuel cell P, so that the polymer electrolyte fuel cell P The remaining fuel can be removed. The timing of supplying water to the first electrode E1 is the time when the load current is continuously applied to the polymer electrolyte fuel cell P, that is, when the voltage drops, that is, the fuel is completely or almost completely in the polymer electrolyte fuel cell P. It is preferably at the point of consumption. In addition, as shown in FIG. 2, if a waste liquid tank 102 is provided outside the first power generation device D1 and a fourth switching cock 103 is provided in the first recovery line 16, a solid polymer may be provided as necessary. The collection destination of generated water and residual fuel in the fuel cell P can be changed from the first to third storage tanks 11, 12, 101 to the waste liquid tank 102.

(Second Embodiment)
Next, a second embodiment of the power generation system of the polymer electrolyte fuel cell and the aging method of the polymer electrolyte fuel cell using the power generation system according to the present invention will be described with reference to FIG. In addition, about the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the second power generation system S2 of the polymer electrolyte fuel cell P according to the second embodiment, as shown in FIG. 3, a receiving tank 22 is provided inside the second power generating device D2, and this receiving tank 22 is provided. Is connected to the polymer electrolyte fuel cell P via the second supply line 23 and the second recovery line 26. The first and second storage tanks 11 and 12 are provided outside the second power generation device D2, and are configured to selectively communicate with the receiving tank 22 via the third supply pump 291. That is, one of the first and second storage tanks 11 and 12 can be attached to the receiving tank 22 as necessary, or both of them can be attached to the receiving tank 22 and either one can be installed as needed. It is also possible to switch so that one side and the receiving tank 22 communicate with each other. In this case, it is preferable to provide second control means C2 for controlling the storage tank that communicates with the receiving tank 22 when the load means 15 stops. Note that the second control means C2 is similar to the first control means C1 in that the magnitude of the load current by the load means 15 is based on the magnitude of the voltage of the polymer electrolyte fuel cell P measured by the voltmeter V. Can be controlled.

  When using 2nd electric power generation system S2 comprised in this way, the aging similar to 1st Embodiment is performed with respect to the polymer electrolyte fuel cell P first. That is, the first fuel is supplied from the first storage tank 11 to the receiving tank 22, the first fuel is supplied from the receiving tank 22 to the first electrode E <b> 1, and the second supply is performed by the oxidant supply means 14. An oxidant is supplied to the electrode E2. Next, a load is applied to the polymer electrolyte fuel cell P by the load means 15 while the first fuel and the oxidant are being supplied. Thereafter, the supply of the first fuel from the first storage tank 11 to the receiving tank 22 is stopped, the second fuel is supplied from the second storage tank 12 to the receiving tank 22, and the second fuel is received. Supply from the tank 22 to the first electrode E1. At this time, the oxidizing agent continues to be supplied to the second electrode E2 by the oxidizing agent supply means 14. The water produced in the polymer electrolyte fuel cell P and the excess first or second fuel remaining in the polymer electrolyte fuel cell P are recovered in the receiving tank 22 via the second recovery line 26. The

  As described above, also in the second embodiment, the same aging method as that in the first embodiment can be performed, so that the internal resistance of the polymer electrolyte fuel cell P can be reliably reduced. Moreover, in 2nd Embodiment, since the 1st and 2nd storage tanks 11 and 12 are arrange | positioned outside the 2nd electric power generating apparatus D2, 2nd electric power generating apparatus D2 can be reduced in size. In the second embodiment, as in the first embodiment, the oxidant may not be supplied to the second electrode E2 during aging.

  In the second power generation system S2, a third storage tank in which water is stored can be provided outside the second power generation device D1. In this case, the first and second storage tanks 11 and 12 and the third storage tank are selectively attached to the third supply pump 291. Further, in the second power generation system S2, a waste liquid tank 102 as shown in FIG. 2 may be provided.

  The present invention will be described more specifically with reference to the following examples and comparative examples. In addition, this invention is not limited to the following Example.

Example 1
First, a gas diffusion layer electrode was produced in the following manner. Namely, platinum ruthenium catalyst-supported carbon particles 2 g (manufactured by Tanaka Kikinzoku Kogyo Co., Ltd., “TEC81E81”), PTFE dispersion 0.6 g (60 wt% solution: manufactured by Aldrich), carbon fiber VGCF 0.4 g (Showa Denko Co., Ltd.) Manufactured), 10 g of distilled water, 12 g of n-butanol and 10 g of t-butanol, and stirred and mixed in a disperser to prepare an anode catalyst layer forming paste composition and a cathode catalyst layer forming paste composition. . Subsequently, this catalyst layer forming paste composition was coated on carbon paper TGP-060 (manufactured by Toray) using an applicator, and dried at 60 ° C. for 30 minutes to obtain a gas diffusion layer electrode.

  Next, a power generation performance evaluation cell was assembled using the produced gas diffusion layer electrode. An anion exchange membrane “FAA” made by Fumatec was prepared as an anion exchange type electrolyte membrane, and a membrane-electrode assembly and a gas diffusion layer electrode were stacked on both sides of the electrolyte membrane so that the catalyst layer was on the electrolyte membrane side. did. A JARI cell was used for the cell, and a silicone gasket (200 μm) made by Chemix was used for the gasket.

  Next, evaluation fuels 1 and 2 (first and second fuels) were produced in the following manner. A fuel for evaluation 1 (first fuel) was obtained by mixing 450 g of distilled water and 50 g of methanol and stirring. Further, 400 g of distilled water and 50 g of potassium hydroxide were mixed, and the potassium hydroxide was dissolved by stirring, and then 50 g of methanol was added and stirred to give a fuel 2 for evaluation of 10 wt% potassium hydroxide (second fuel) Fuel).

  Using the cell, the evaluation fuel 1, and the evaluation fuel 2, aging was performed as follows. The cell was set in the evaluation device and waited until the set temperature reached 50 ° C. After the temperature became constant, evaluation fuel 1 was flowed to the anode at 2 ml / min and high purity air at 200 ml / min was flowed to the cathode. After about 30 minutes, a load current was applied for about 1 minute so that the voltage was around 0 to 0.1V. After turning off the load current, it waited for about 10 minutes until the OCV recovered, and the load current was again applied for about 1 minute. Thereafter, the fuel flowing to the anode was changed from the evaluation fuel 1 to the evaluation fuel 2, and the evaluation fuel 2 was continuously supplied to the anode for about 20 minutes.

(Example 2)
First, a gas diffusion layer electrode was produced in the following manner. That is, 1 g of palladium catalyst-supporting carbon particles (manufactured by E-TEC), 0.8 g of PTFE dispersion (60 wt% solution: manufactured by Aldrich), 0.1 g of carbon fiber VGCF (manufactured by Showa Denko KK), and 1 g of distilled water. The paste composition for anode catalyst layer formation was produced by mix | blending and stirring and mixing with a disperser. The same cathode catalyst layer forming paste as in Example 1 was used. Subsequently, these catalyst layer forming paste compositions were coated on carbon paper TGP-060 (manufactured by Toray) using an applicator and dried at 60 ° C. for 30 minutes to obtain a gas diffusion layer electrode.

  Using the gas diffusion layer electrode, a power generation performance evaluation cell is assembled in the same manner as in Example 1, and the evaluation fuel 1 and evaluation fuel 2 are used for this cell in the same manner as in Example 1. Aging was performed.

(Example 3)
After mixing 435 g of distilled water and 15 g of potassium hydroxide and dissolving the potassium hydroxide by stirring, 50 g of methanol is added and stirred to give 3 wt% potassium hydroxide for evaluation fuel 3 (third fuel) Aging was performed by the same cell and method as in Example 1 using evaluation fuel 3 (third fuel) instead of evaluation fuel 1 (first fuel).

(Comparative Example 1)
Using the same cell and fuel for evaluation 2 as in Example 1, aging was performed as follows. The cell was set in the evaluation device and waited until the set temperature reached 50 ° C. After the temperature became constant, evaluation fuel 2 was flowed to the anode at 2 ml / min and high-purity air at 200 ml / min was flowed to the cathode. After about 10 minutes, a load current was applied for about 1 minute so that the voltage was around 0 to 0.1V. After turning off the load current, it waited for about 10 minutes until the OCV recovered, and the load current was again applied for about 1 minute. Thereafter, the fuel 2 for evaluation was further allowed to flow through the anode for about 20 minutes.

(Comparative Example 2)
Using the same cell and fuel for evaluation 2 as in Example 2, aging was performed in the same manner as in Comparative Example 1.

(Comparative Example 3)
Mixing 425 g of distilled water and 25 g of potassium hydroxide, dissolving potassium hydroxide by stirring, adding 50 g of methanol and stirring to give 5% by weight of potassium hydroxide for evaluation 4 (fourth fuel) Aging was performed by the same cell and method as in Example 1 using evaluation fuel 4 (fourth fuel) instead of evaluation fuel 1 (first fuel).

(Evaluation)
When IV measurement of each cell in Example 1 and Comparative Example 1 was performed, it was found that the cell of Example 1 can obtain an extremely high output as compared with the cell of Comparative Example 1 as shown in FIG. . Moreover, when IV measurement of each cell in the said Example 2 and the comparative example 2 was performed, as shown in FIG. 5, the cell of Example 2 can obtain a very high output compared with the cell of the comparative example 2. all right. Furthermore, when IV measurement of each cell in Example 3 and Comparative Example 3 was performed, the cell of Example 3 obtained high output as in Example 1 as shown in FIG. Only low output was obtained.

S1, S2 Power generation system P Solid polymer fuel cell M Ion conductive polymer electrolyte membrane E1 First electrode (one electrode)
E2 Second electrode (the other electrode)
S resistance sensor C1, C2 first and second control means 11 first storage tank 12 second storage tank 101 third storage tank 13, 23 first and second supply lines 14 oxidant supply means 15 load means

Claims (13)

Ion conductive polymer electrolyte membrane, and have a formed on both surfaces electrodes of the ion conductive polymer electrolyte membrane, the second fuel containing an alcohol and an alkaline substance is supplied to one electrode and the other an oxidizing agent A method for aging a polymer electrolyte fuel cell that generates electricity by supplying to an electrode of
A step of preparing the polymer electrolyte fuel cell,
A first fuel process for supplying to the electrodes of the prior SL hand is content and alkaline substance containing alcohol is 3 wt% or less,
Passing a load current through the polymer electrolyte fuel cell supplied with the first fuel;
After flushing the load current, and supplying said second fuel to one of the electrodes above,
A method for aging a polymer electrolyte fuel cell.   The aging method according to claim 1, wherein the alkaline substance contained in the second fuel is potassium hydroxide, sodium hydroxide, or ammonia.   3. The second fuel is supplied to the one electrode after flowing a load current for 5 seconds or longer to the polymer electrolyte fuel cell to which the first fuel is supplied. Aging method. The aging method according to claim 1, further comprising a step of supplying water to the one electrode after flowing the load current. Ion conductive polymer electrolyte membrane, and have a formed on both surfaces electrodes of the ion conductive polymer electrolyte membrane, the second fuel containing an alcohol and an alkaline substance is supplied to one electrode and the other an oxidizing agent A power generation system for a polymer electrolyte fuel cell that generates power by supplying to the electrode of
A first storage tank for storing a first fuel containing alcohol and having an alkaline substance content of 3% by weight or less;
A second storage tank for storing the second fuel;
A supply line for selectively supplying the first fuel in the first storage tank or the second fuel in the second storage tank to one electrode of the polymer electrolyte fuel cell;
An oxidant supply means for supplying an oxidant to the other electrode of the polymer electrolyte fuel cell;
Load means electrically connected to the polymer electrolyte fuel cell to flow a load current;
Equipped with a,
The supply line supplies the first fuel to the one electrode, and after a load current is passed through the polymer electrolyte fuel cell by the load means, the second fuel is supplied to the one electrode. We feed, solid polymer electrolyte fuel cell power generation system. The power generation system according to claim 5 , further comprising a voltmeter that measures a voltage applied to the polymer electrolyte fuel cell. The power generation system according to claim 6 , further comprising a control unit that controls a magnitude of a load current by the load unit based on a voltage measured by the voltmeter. A third storage tank for storing water;
The supply line selectively uses the first fuel in the first storage tank, the second fuel in the second storage tank, or water in the third storage tank as the one electrode. The power generation system according to any one of claims 5 to 7 , which is supplied. 9. The apparatus according to claim 5, further comprising a recovery line for recovering the first fuel and the second fuel remaining in the one electrode to the first storage tank and the second storage tank, respectively. The power generation system according to Crab. A power generation system of a polymer electrolyte fuel cell having an ion conductive polymer electrolyte membrane and electrodes formed on both surfaces of the ion conductive polymer electrolyte membrane,
A first storage tank for storing a first fuel containing alcohol and having an alkaline substance content of 3% by weight or less;
A second storage tank for storing a second fuel containing alcohol and an alkaline substance;
A receiving tank in selective communication with the first or second storage tank;
A supply line for supplying the first or second fuel in the receiving tank to one electrode of the polymer electrolyte fuel cell;
An oxidant supply means for supplying an oxidant to the other electrode of the polymer electrolyte fuel cell;
A load means electrically connected to the polymer electrolyte fuel cell to flow a load current;
A power generation system for a polymer electrolyte fuel cell. The power generation system according to claim 10 , further comprising a voltmeter that measures a voltage applied to the polymer electrolyte fuel cell. The power generation system according to claim 11 , further comprising a control unit that controls a magnitude of a load current by the load unit based on a voltage measured by the voltmeter. A third storage tank for storing water;
The power generation system according to any one of claims 10 to 12 , wherein the receiving tank selectively communicates with the first storage tank, the second storage tank, or the third storage tank.