JP2006040769A - Cartridge for fuel cell, and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cartridge for a fuel cell in which by-products generated in the fuel cell are recovered by a constitution easy to handle, and in which carbon dioxide which has been made harmless is discharged to the exterior of the cell. <P>SOLUTION: This is the cartridge for the fuel cell which is installed on the fuel cell detachably and supplies the fuel 124 to the fuel cell, and which houses the fuel 124, and which is provided with a fuel room 1221 having an injection port 1223 to supply the fuel 124 to the fuel cell, and provided with a recovery room 1703 which has a recovery port 1707 to recover an exhaust gas 1705 exhausted from the fuel cell and an exhaust port 1713 to discharge the exhaust gas 1705 to the exterior, and in which water 1701 is housed therein in order to dissolve chemical materials contained in the exhaust gas. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cartridge for a fuel cell, and more particularly, to a cartridge for a fuel cell provided with means for discharging exhaust gas containing by-products generated inside the cell to the outside.

  A fuel cell is composed of a fuel electrode and an oxidant electrode, and an electrolyte provided therebetween. The fuel cell is supplied with fuel, and the oxidant electrode is supplied with an oxidant to generate electricity by an electrochemical reaction. In general, hydrogen is used as a fuel. However, in recent years, development of a direct type fuel cell using methanol which is inexpensive and easy to handle as a fuel has been actively performed.

  When hydrogen is used as the fuel, the reaction at the fuel electrode is represented by the following formula (1).

3H ₂ → 6H ⁺ + 6e ⁻ (1)

  When methanol is used as the fuel, the reaction at the fuel electrode is represented by the following equation (2).

CH ₃ OH + H ₂ O → 6H ⁺ + CO ₂ + 6e ⁻ (2)

  In either case, the reaction at the oxidant electrode is represented by the following formula (3).

3 / 2O ₂ + 6H ⁺ + 6e ⁻ → 3H ₂ O (3)

  In particular, in a direct type fuel cell, hydrogen ions can be obtained from an aqueous methanol solution, so that a reformer or the like is not necessary, and there are great advantages for miniaturization and practical use of the fuel cell. Further, since a liquid methanol aqueous solution is used as a fuel, the energy density is very high.

  In such a direct fuel cell, as shown in the above formula (2), carbon dioxide is generated by an electrochemical reaction at the fuel electrode. Further, as shown in the above formula (3), water is generated at the oxidant electrode. In the fuel cell, other than these, unreacted fuel and harmful substances such as formaldehyde and formic acid which are by-products of the electrochemical reaction are also generated. Since the fuel also crosses over to the oxidant electrode side, such a by-product is generated not only on the fuel electrode side but also on the oxidant electrode side.

  Patent Document 1 discloses a reaction product discharge port for discharging a reaction product generated by an electrochemical reaction of a fuel cell, and a reaction product storage chamber connected to the reaction product discharge port for storing the reaction product. And a container containing the fuel cell. Also here, unreacted fuel and adsorbents such as activated carbon and zeolite for adsorbing harmful substances such as formaldehyde and formic acid which are byproducts of electrochemical reaction, silver for decomposing these harmful substances, etc. It is described that these noble metal catalysts, inorganic catalysts, or microbial catalysts are added alone or in appropriate combination in a container. Thereby, even if it is a case where these harmful substances are collect | recovered in the container, the problem on a process or recycling of a container can be eliminated.

  Further, in Patent Document 2, the inside is divided into two chambers by a partition made of a material that does not transmit water, and one of the two chambers divided by the partition contains an exhaust from the fuel cell. A fuel cartridge for use is disclosed.

  In one chamber of the fuel cartridge, the fuel supplied to the fuel cell is accommodated, and the internal volume decreases as the fuel is consumed. In the other chamber of the fuel cartridge, the internal volume is reduced by the discharge from the fuel cell. The composition is increasing. A water-absorbing material is accommodated in the other chamber of the fuel cartridge, and the intermediate product is absorbed and held together with water containing methanol contained in the discharge. As the water absorbing material, an anionic water supply polymer or a nonionic water absorption polymer is used. In this way, the waste contained in the fuel cartridge is removed from the fuel cell together with the fuel cartridge when the fuel runs out and discarded.

Further, Patent Document 3 discloses a fuel cell having a product storage unit that seals and connects a fuel storage container, a fuel supply unit, a fuel electrode, and a fuel discharge unit, and absorbs a fuel oxidation product discharged from the fuel electrode. A system is disclosed. For this product absorption section, activated carbon that immobilizes carbon dioxide by physical adsorption or an alkaline solid or liquid that absorbs carbon dioxide by a chemical reaction is used.
JP 2003-132931 A JP 2003-92128 A JP 2003-257466 A

  However, in the conventional fuel cell cartridge described in the above-mentioned documents 1 and 2, the intermediate product is collected in the container together with the product such as water or carbon dioxide generated in the fuel cell and discarded together with the fuel cell cartridge. It is configured. For this reason, there is a problem that the container is filled with carbon dioxide, the recovery container expands, and the internal pressure in the container increases.

  Further, in the conventional fuel cell cartridge, when the waste is absorbed and collected by the water-absorbing material, the capacity of the water-absorbing material for collecting the waste increases with time, and the efficiency of absorbing the waste with time is increased. There was a problem that it decreased. In addition, in the conventional fuel cell cartridge, a solid adsorbent is used, but in this case, if the discharge contains water vapor, the adsorption efficiency decreases because the water vapor is adsorbed on the surface of the adsorbent. There was a problem.

  Patent Document 3 discloses an example using a liquid that absorbs carbon dioxide, so problems such as expansion of the collection container can be avoided. However, since it is a closed system, expansion is inevitable when using a material that does not absorb carbon dioxide as an absorbent. Therefore, the absorbent is limited to an alkaline solution or the like. For example, since only 1.1 ml of carbon dioxide is dissolved in 1 ml of water (water temperature 25 ° C.), water cannot be used in such a sealed structure. Further, since this fuel cell cartridge is configured to collect only the emissions from the fuel electrode side, unreacted fuel gas and carbon dioxide crossing over to the oxidizer electrode and its by-products are not recovered.

  Moreover, when absorption efficiency fell with absorption of a product, it was necessary to replace | exchange each container of a product absorption part, and the reuse of a container was not made.

  The present invention has been made in view of the above circumstances, and has an object of collecting a by-product generated in the fuel cell with a configuration that is easy to handle, and detoxifying the carbon dioxide that has been rendered harmless. Accordingly, it is an object of the present invention to provide a fuel cell cartridge that can withstand multiple use without causing expansion of a container due to gas filling, and to provide a technology capable of improving the maintainability and reliability of the fuel cell system. .

  According to the present invention, there is provided a fuel cell cartridge that is detachably attached to a fuel cell and supplies liquid fuel to the fuel cell, the fuel supply port for supplying the liquid fuel to the fuel cell. A fuel chamber for storing the liquid fuel, an exhaust gas recovery port for recovering exhaust gas discharged from the fuel cell, and a gas exhaust port for discharging the exhaust gas to the outside, and contained in the exhaust gas inside There is provided a fuel cell cartridge comprising an exhaust gas recovery chamber in which a liquid for dissolving a chemical substance is stored.

  According to the present invention, exhaust gas containing fuel gas such as methanol and by-products (formic acid, methyl formate, formaldehyde, etc.) generated in the battery is contacted with the liquid in the exhaust gas recovery chamber to pass through the exhaust gas. By-products contained therein can be dissolved and recovered, thereby detoxifying carbon dioxide to the outside of the battery, and the exhaust gas recovery chamber expands due to gas filling, or the internal pressure is high. I don't get bored.

  In this way, only the by-product contained in the exhaust gas can be recovered in the liquid, and the detoxified carbon dioxide can be released to the outside of the battery, so the volume of the liquid containing the by-product increases with time. I don't have to. In addition, the absorption efficiency does not decrease over time unlike when a water-absorbing material is used.

  In the fuel cell cartridge of the present invention, the exhaust gas recovery port can recover the exhaust gas discharged from the oxidant electrode of the fuel cell. According to this configuration, unreacted fuel gas and carbon dioxide crossing over the oxidant electrode of the fuel cell and by-products thereof can be recovered.

  In the fuel cell cartridge of the present invention, the exhaust gas can be configured to be guided into the liquid. According to this configuration, by-products contained in the exhaust gas can be efficiently dissolved in the liquid by introducing the exhaust gas into the liquid.

  The fuel cell cartridge of the present invention includes a porous bubble foaming portion provided in the exhaust gas recovery port, and the exhaust gas can be introduced as bubbles into the exhaust gas recovery chamber through the bubble foaming portion. .

  Here, a porous air stone can be used as the bubble foaming portion. The porous air stone is, for example, made of ceramic hardened at a high temperature of about 1300 ° C. or made of urethane resin obtained by foaming, compressing and molding a plastic material. Is introduced into the exhaust gas recovery chamber as bubbles, so that the dissolution efficiency of the by-product in the liquid can be improved.

  In the fuel cell cartridge of the present invention, a gas-liquid separation membrane can be provided in the exhaust gas recovery chamber. Here, the gas-liquid separation membrane is a hydrophobic membrane made of, for example, polyethersulfone or an acrylic copolymer. According to this configuration, the exhaust gas that has passed through the liquid in the exhaust gas recovery chamber can be separated via the gas-liquid separation membrane, and detoxified carbon dioxide can be released to the outside.

  The fuel cell cartridge according to the present invention includes a gas adsorption filter provided in the gas discharge port, and the exhaust gas that has passed through the gas-liquid separation membrane is discharged to the outside through the gas adsorption filter. can do.

  Here, examples of the material for the gas adsorption filter include activated carbon, an activated carbon surface modified with an amine compound, dinitrophenylhydrazine (DNPH), or potassium permanganate. In particular, an activated carbon surface modified with an amine compound is preferable from the viewpoint of adsorption capacity. Since the exhaust gas is discharged to the outside of the battery through the gas adsorption filter, the by-product contained in the exhaust gas that has not been recovered by the liquid can be recovered, and the by-product can be more reliably removed from the exhaust gas. .

  The fuel cell cartridge according to the present invention may include an oxidizer provided at the gas discharge port for oxidizing the exhaust gas that has passed through the gas-liquid separation membrane.

  Here, the oxidation part may be a catalyst provided at the gas outlet. Examples of the catalyst used here include Pt, Ti, Cr, Fe, Co, Ni, Cu, Zn, Nb, Mo, Ru, Pd, Ag, In, Sn, Sb, W, Au, Pb, and Bi. A metal, an alloy, or an oxide thereof containing at least one of the above can be used. These catalysts can oxidize exhaust gas efficiently.

  Further, the oxidation part may be provided with an oxidation promoting means for promoting the oxidation of the exhaust gas by the catalyst. The oxidation accelerating means can be configured to include, for example, a heating unit for heating a gas or a catalyst. In this way, the by-product contained in the exhaust gas after passing through the liquid in the exhaust gas recovery chamber can be efficiently and reliably oxidized. In addition, even after the fuel cell has been used for a long time, even if components that could not be oxidized by the catalyst or liquefied components adhered to the catalyst, such components would be oxidized efficiently and more reliably and completely. The performance can be maintained. In addition, the oxidation promoting means can have an oxygen supply part that supplies a gas containing oxygen.

  In the fuel cell cartridge of the present invention, the liquid is not limited to a material that absorbs carbon dioxide, and water and alcohol that are easily available can also be used. However, the pH is preferably 2 or more and more preferably pH 3 or more so that members such as a current collector are not significantly oxidized even if leaked. In addition, since the inventors have confirmed that when a strong alkaline liquid adheres to the electrolyte membrane, the proton conductivity is deteriorated, the pH is preferably 9 or less, and preferably 8 or less. More preferred. A representative liquid that meets the gist of the present invention is water. Since water is a polar solvent, it easily dissolves by-products and is particularly suitable for the purposes of the present invention.

  According to the present invention, a fuel cell including a fuel electrode, an oxidant electrode, and an electrolyte membrane sandwiched therebetween, a fuel supply system that supplies liquid fuel to the fuel electrode, and the fuel electrode or the oxidant A gas recovery system for recovering gas generated at the pole; and a fuel cell cartridge detachably attached to the fuel supply system and the gas recovery system, wherein the fuel cell cartridge is for the fuel cell. A fuel cell system is provided that is a cartridge.

  According to this configuration, since the exhaust gas discharged from both the fuel electrode and the oxidant electrode of the fuel cell can be recovered by the gas recovery system, unreacted fuel gas that has crossed over to the oxidant electrode, By passing the exhaust gas containing carbon and its by-products in contact with a liquid, the by-product contained in the exhaust gas generated from the oxidizer electrode can be dissolved and recovered. Thus, by-products generated in the fuel cell can be recovered in the fuel cartridge, and detoxified carbon dioxide can be released to the outside.

  In the fuel cell system of the present invention, the gas recovery system has an exhaust port for discharging the gas recovered, and the exhaust gas recovery port of the fuel cell cartridge and the exhaust port of the gas recovery system of the fuel cell are provided. A diaphragm provided so as to cover either one, and a hollow needle provided on the other, and when the fuel cell cartridge is connected to the fuel cell, the hollow needle penetrates the diaphragm, and the exhaust gas The collection port and the discharge port can communicate with each other.

  In the fuel cell system of the present invention, the fuel cell can be a direct fuel cell that supplies liquid fuel to the fuel electrode. As the fuel, methanol, ethanol, dimethyl ether, other alcohols, or an organic liquid fuel such as a liquid hydrocarbon such as cycloparaffin can be used.

  In the fuel cell system of the present invention, the fuel cell system is provided between the exhaust port of the gas recovery system of the fuel cell and the exhaust gas recovery port of the fuel cell cartridge, and is recovered by the gas recovery system of the fuel cell. An oxidation part that oxidizes the exhaust gas can be included.

  Here, the oxidation unit may be a catalyst provided between the exhaust port of the gas recovery system of the fuel cell and the exhaust gas recovery port of the fuel cell cartridge. Examples of the catalyst used here include Pt, Ti, Cr, Fe, Co, Ni, Cu, Zn, Nb, Mo, Ru, Pd, Ag, In, Sn, Sb, W, Au, Pb, and Bi. A metal, an alloy, or an oxide thereof containing at least one of the above can be used. These catalysts can oxidize exhaust gas efficiently.

  Further, the oxidation part may be provided with an oxidation promoting means for promoting the oxidation of the exhaust gas by the catalyst. The oxidation accelerating means can be configured to include, for example, a heating unit for heating a gas or a catalyst. In this way, it is possible to efficiently and reliably oxidize unreacted fuel gas and by-products contained in the exhaust gas before passing through the liquid in the exhaust gas recovery chamber. In addition, even after the fuel cell has been used for a long time, even if components that could not be oxidized by the catalyst or liquefied components adhered to the catalyst, such components would be oxidized efficiently and more reliably and completely. The performance can be maintained. In addition, the oxidation promoting means can have an oxygen supply part that supplies a gas containing oxygen.

  According to the present invention, since the exhaust gas recovery chamber in which the liquid is accommodated is provided, the by-product generated in the fuel cell is recovered, and the detoxified carbon dioxide is released to the outside of the battery a plurality of times. It is possible to provide a fuel cell cartridge that can withstand the use of the fuel cell.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  Examples of fuel cell cartridges according to the present invention will be described below. In the following example, a direct methanol fuel cell will be described as an example. However, the type of fuel is not limited to methanol, and various modes can be adopted.

The fuel cell cartridge according to the embodiment of the present invention is used for a fuel cell and can be replaced. The fuel cell can be applied to small electric devices such as a mobile phone, a portable personal computer such as a notebook, a PDA (Personal Digital Assistant), various cameras, a navigation system, and a portable music player.
(First embodiment)
FIG. 1 is a diagram schematically showing the structure of a fuel cell cartridge in the present embodiment. 1A is a side sectional view of the fuel cell cartridge, and FIG. 1B is a top view of the fuel cell cartridge of FIG. 1A.

  The fuel cartridge 1220 includes a fuel chamber 1221 that stores the fuel 124 and a recovery chamber 1703 that stores water 1701 that dissolves substances contained in the exhaust gas 1705 discharged from a fuel cell (not shown). The fuel chamber 1221 includes an inlet 1223 for supplying the fuel 124 to the fuel cell, and a diaphragm 1245 provided at an end of the inlet 1223. The recovery chamber 1703 has one end where a recovery port 1707 for recovering the exhaust gas 1705 is opened and the other end where an exhaust port 1713 for releasing the exhaust gas 1705 is opened. The recovery port 1707 recovers the exhaust gas 1705 discharged from at least the oxidant electrode of the fuel cell. The recovery chamber 1703 includes a diaphragm 1709 provided at the end of the recovery port 1707, a gas-liquid separation membrane 1711 that separates the exhaust gas 1705 that has passed through the water 1701 from the water 1701, and a gas adsorption filter 1715 provided in the discharge port 1713. And including.

  As described above, the recovery chamber 1703 is divided into the first region and the second region by the gas-liquid separation film 1711. Water 1701 is accommodated in the first region, and a gas adsorption filter 1715 is provided in the second region. The exhaust gas 1705 that has passed through the gas-liquid separation membrane 1711 is configured to be discharged to the outside through the gas adsorption filter 1715.

  In the present embodiment, the water 1701 is preliminarily stored in the fuel cartridge 1220. However, the present invention is not limited to this, and a closeable inlet for injecting the water 1701 into the fuel cartridge 1220 is provided. It is also possible to adopt a configuration in which water 1701 can be injected from the injection port. Further, the fuel cartridge 1220 is provided with a closeable discharge port for discharging the water 1701, and the water 1701 after dissolving the by-product of the exhaust gas 1705 is discharged through the discharge port and recovered by a predetermined waste liquid treatment system. You can also. After the water 1701 is discharged from the outlet, the water 1701 can be injected again from the inlet. In this way, the water 1701 can be replaced.

  Further, the collection chamber 1703 can be attached to and detached from the fuel cartridge 1220 and can be replaced. In the fuel cartridge 1220 of the present embodiment, in a normal operation state, the water 1701 has a necessary and sufficient capacity to dissolve by-products contained in the exhaust gas 1705. The configuration that makes it possible to exchange is useful when an abnormal operation is assumed in which excessive by-products are generated.

  In addition, assuming such a case, the fuel cartridge 1220 can be provided with a detection unit that detects whether a by-product dissolved in the water 1701 exceeds a predetermined amount and is saturated.

  The detection unit is configured such that a litmus liquid or a BTB solution that can identify the pH of the water 1701 by color change is dissolved in the water 1701 in advance, and a window is provided in the recovery chamber 1703 so that the internal water 1701 can be seen from the outside. It can be. With this configuration, water 1701 whose pH has changed to acidic due to dissolution of by-products such as formaldehyde and the color has changed can be confirmed from the window, so the water 1701 is notified that the by-products are saturated. It will be possible.

  Alternatively, the detection unit provides the collection chamber 1703 with a pair of electrodes using water 1701 as a medium, and measures the conductivity between the conduction electrodes that can be electrically connected to the pair of electrodes and the conduction electrodes. The measurement unit and the housing 1203 may be provided. With this configuration, when the by-product is saturated with water 1701, the conductivity is lowered, so that the state can be detected. The detection unit can be provided with a means for notifying, for example, a display unit when the measured conductivity falls below a predetermined value.

  The diaphragm 1245 and the diaphragm 1709 are preferably made of a material that has elasticity and stretchability and does not transmit the fuel 124 and the water 1701.

  In the present embodiment, the exhaust gas 1705 is introduced into and passed through the water 1701, but is not limited thereto. For example, a configuration in which the exhaust gas 1705 passes through the upper portion of the water 1701 may be used. Alternatively, the water 1701 in the form of mist, drops, or flowing water may be sprayed, fountained, or flowing on the passage of the exhaust gas 1705 in the recovery chamber 1703.

  The gas-liquid separation membrane 1711 is a hydrophobic membrane made of, for example, polyethersulfone or an acrylic copolymer. As such a gas-liquid separation membrane 1711, Gore-Tex (manufactured by Japan Gore-Tex Co., Ltd.) (registered trademark), Versapore (manufactured by Nippon Pole Co., Ltd.) (registered trademark), Supor (manufactured by Nippon Pole Co., Ltd.) (Registered trademark) and the like are exemplified.

  FIG. 2 is a cross-sectional view showing a location where the fuel cartridge 1220 is attached to the fuel cell.

  The fuel cell casing 1203 communicates the fuel supply channel 1207 for supplying the fuel 124 to the fuel cell, the exhaust gas recovery channel 1721 for recovering the exhaust gas 1705 generated by the fuel cell, and the fuel supply channel 1207 to the outside. The hollow needle 1257 provided in this manner and the hollow needle 1723 provided so as to communicate with the exhaust gas recovery flow path 1721 and the outside.

  The fuel cartridge 1220 includes a spring mounting portion 1727 to which a convex portion 1725 is attached via a spring 1726. The convex portion 1725 protrudes toward the outer side of the side surface of the fuel cartridge 1220, and faces the outer side surface of the fuel cartridge 1220. Pressed.

  The fuel cell housing 1203 has a concave portion 1729 into which the convex portion 1725 of the fuel cartridge 1220 is fitted. Further, the fuel cartridge 1220 has a release portion (not shown) that releases the elasticity of the spring 1726 and detaches the convex portion 1725 from the concave portion 1729 of the housing 1203. The fuel cartridge 1220 and the fuel cell housing 1203 configured as described above are detachably connected to each other by fitting the convex portion 1725 of the fuel cartridge 1220 into the concave portion 1729 of the housing 1203. It should be understood by those skilled in the art that the configuration for detachably connecting the fuel cartridge 1220 to the fuel cell housing 1203 is not limited to this, and there are various modifications.

  In FIG. 2, when the fuel cartridge 1220 is mounted on the fuel cell casing 1203, the diaphragm 1245 and the diaphragm 1709 of the fuel cartridge 1220 are punctured by the hollow needle 1257 and the hollow needle 1723 of the casing 1203, respectively. The fuel chamber 1221 and the fuel supply channel 1207 and the recovery chamber 1703 of the fuel cartridge 1220 and the exhaust gas recovery channel 1721 are communicated with each other via the hollow needle 1257 and the hollow needle 1723. Here, it is preferable that the diaphragm 1245 and the diaphragm 1709 are made of a stretchable material that can shield a perforated portion between the hollow needle 1257 and the hollow needle 1723. The diaphragm 1245 and the diaphragm 1709 can be made of, for example, high density rubber or a septum.

  The effects of the fuel cartridge 1220 configured as described above will be described below with reference to FIGS. 1 and 2.

  When the fuel cartridge 1220 is mounted on the fuel cell housing 1203, the hollow needle 1723 pierces the diaphragm 1709 of the fuel cartridge 1220, and the recovery chamber 1703 of the fuel cartridge 1220 and the exhaust gas recovery flow path 1721 of the fuel cell are hollow needles. 1723 is communicated.

  As a result, the exhaust gas 1705 generated in the fuel cell and recovered in the exhaust gas recovery flow path 1721 is introduced into the recovery chamber 1703 of the fuel cartridge 1220 via the hollow needle 1723. While the exhaust gas 1705 introduced into the recovery chamber 1703 of the fuel cartridge 1220 moves a distance L in the longitudinal direction of the recovery chamber 1703 (see FIG. 1), by-products contained in the exhaust gas 1705 are accommodated in the recovery chamber 1703. It is dissolved in water 1701 and collected. By-products contained in the exhaust gas 1705 include unreacted fuel and electrochemical reaction by-products such as formaldehyde, formic acid, and methyl formate.

  These by-products are easily dissolved in the water 1701 which is a polar solvent, and are dissolved in the water 1701 while passing through the water 1701 accommodated in the recovery chamber 1703. Here, the water 1701 has a necessary and sufficient capacity to dissolve by-products contained in the exhaust gas 1705.

  In this embodiment mode, water 1701 is used as a liquid for dissolving by-products, but the present invention is not limited to this. The liquid may be another polar solvent, such as an alcohol or ether. However, the water 1701 is suitable as a liquid because it is readily available and easy to handle.

  The exhaust gas 1705 is discharged to the discharge port 1713 of the recovery chamber 1703 through the gas-liquid separation membrane 1711. Further, the exhaust gas 1705 passes through the gas adsorption filter 1715, by-products remaining in the exhaust gas 1705 are further removed, and discharged as harmless exhaust gas 1717 to the outside of the fuel cartridge 1220. The exhaust gas 1717 mainly contains carbon dioxide.

  In this way, only by-products are recovered in the water 1701, and the detoxified exhaust gas 1717 is released to the outside. Here, the volume of water 1701 does not increase over time even when by-products are collected, and the absorption efficiency decreases over time as in the case of using a water-absorbing material. Nor.

  As described above, according to the present invention, only the by-product generated in the fuel cell can be recovered by the fuel cartridge 1220, and detoxified carbon dioxide can be released to the outside of the cell.

In addition, the volume of the liquid containing the by-product does not increase with time, and the absorption efficiency does not decrease with time unlike when using a water-absorbing material. By-products in exhaust gas can be efficiently recovered.
(Second embodiment)
FIG. 3 is a diagram showing another embodiment of the fuel cell cartridge. The fuel cartridge recovery chamber 1703 includes a porous air stone 1731 provided in the recovery port 1707. Due to the air stone 1731, the exhaust gas 1705 is introduced into the recovery chamber 1703 as bubbles 1733.

Here, as the porous air stone 1731, for example, a ceramic material hardened at a high temperature of about 1300 degrees or a urethane resin material obtained by foaming, compressing and molding a plastic material is used. Can do. Alternatively, the air stone 1731 can be pumice or the like. The air stone 1731 can have various shapes such as a spherical shape, a cylindrical shape, and a plate shape. By introducing the exhaust gas 1705 into the recovery chamber 1703 as the bubbles 1733 via the air stone 1731, the efficiency of dissolving the by-product in the water 1701 can be improved.
(Third embodiment)
FIG. 4 is a view showing another embodiment of the fuel cell cartridge. The fuel cartridge 1220 has a catalyst 835 that oxidizes the exhaust gas 1705 that has passed through the gas-liquid separation membrane 1711 in a discharge passage 831 provided in the discharge port 1713. Examples of the catalyst used here include Pt, Ti, Cr, Fe, Co, Ni, Cu, Zn, Nb, Mo, Ru, Pd, Ag, In, Sn, Sb, W, Au, Pb, and Bi. A metal, an alloy, or an oxide thereof containing at least one of the above can be used. These catalysts can oxidize the exhaust gas 1705 efficiently.

Further, in order to promote the oxidation of the exhaust gas 1705 by the catalyst 835, an oxidation promoting means (not shown) may be provided. The oxidation promoting means can be configured to include, for example, a heating unit (not shown) for heating a gas or a catalyst. In this way, the by-product contained in the exhaust gas 1705 after passing through the liquid in the recovery chamber 1703 can be oxidized efficiently and reliably. In addition, even after the fuel cell has been used for a long time, even if components that could not be oxidized by the catalyst or liquefied components adhered to the catalyst, such components would be oxidized efficiently and more reliably and completely. The performance can be maintained. The oxidation promoting means can have an oxygen supply part (not shown) for supplying a gas containing oxygen.
(Fourth embodiment)
FIG. 5 is a block configuration diagram of the fuel cell system according to the embodiment of the present invention.

  A fuel cell system 1740 according to the present embodiment includes a fuel cell group 1000 including a plurality of fuel cell unit cells (not shown), and a fuel cartridge 1220 that supplies fuel 124 to the fuel cell group 1000. In the fuel cell system 1740, the fuel cartridge 1220 is detachably connected to a housing 1203 in which the fuel cell group 1000 is provided.

  The fuel cell unit cell of the fuel cell group 1000 includes a fuel electrode (not shown), an oxidant electrode (not shown), and a solid electrolyte membrane (not shown) provided therebetween. 124, the oxidant electrode 126 is supplied with the oxidant 126, and electricity is generated by an electrochemical reaction. The fuel cell unit cell is a direct type fuel cell in which liquid fuel is supplied to the fuel electrode. As the fuel 124, an organic liquid fuel such as methanol, ethanol, dimethyl ether, other alcohols, or a liquid hydrocarbon such as cycloparaffin can be used. The organic liquid fuel can be an aqueous solution. Usually, air can be used as the oxidant 126, but oxygen gas may be supplied.

  The fuel cell system 1740 includes a fuel supply system (including the fuel supply channel 1207 in FIG. 2) that supplies the fuel 124 to the fuel electrode, and a gas recovery system that recovers gas generated at the fuel electrode or the oxidant electrode. (Including the exhaust gas recovery passageway 1721 of FIG. 2), and a fuel cartridge 1220 that is detachably attached to the fuel supply system and the gas recovery system.

  In the fuel cell system 1740 of the present embodiment, the gas recovery system recovers at least the gas generated at the oxidant electrode. Thereby, the unreacted fuel gas and carbon dioxide crossing over the oxidant electrode of the fuel cell and the by-products thereof can be recovered.

  The fuel cell system 1740 includes a fuel flow path 310 that supplies fuel 124 to the fuel electrode of the fuel cell unit cell of the fuel cell group 1000, and an oxidant 126 to the oxidant electrode of the fuel cell unit cell of the fuel cell group 1000. And an oxidant channel 312 to be supplied.

  The fuel cell system 1740 further includes a fuel container 811 that temporarily stores the fuel 124 supplied from the fuel cartridge 1220. The fuel 124 is injected from the fuel chamber 1221 of the fuel cartridge 1220 into the fuel container 811 via the pump 1751 and further supplied to the fuel flow path 310 via the pump 1753. The oxidant 126 is supplied to the oxidant flow path 312 via the pump 1755.

  In the fuel cell system 1740, the gas-liquid separating the unreacted fuel gas 1741 generated from the fuel 124 and the exhaust gas 1742 containing by-products generated by the electrochemical reaction of the fuel cell in the fuel container 811 and the fuel flow path 310. It has a gas-liquid separation membrane chamber 815 provided with a separation membrane.

  The exhaust gas 1743 separated by the gas-liquid separation membrane in the gas-liquid separation membrane chamber 815 and the exhaust gas 1745 containing by-products generated by the electrochemical reaction of the fuel cell in the oxidant channel 312 are connected via the pump 1757. The fuel is collected in the collection chamber 1703 of the fuel cartridge 1220.

  In FIG. 5, a pump 1751, a fuel container 811, a pump 1753, and a fuel flow path 310 constitute a fuel supply system, and a gas-liquid separation membrane chamber 815 and a pump 1757 constitute a gas recovery system.

  The pumps 1751, 1753, 1755, and 1757 are controlled in flow rate by a control unit (not shown).

  Next, the effect of the fuel cell system 1740 configured as described above will be described with reference to FIG.

  In the fuel cell system 1740, unreacted fuel gas 1741 generated from the fuel 124 supplied from the fuel cartridge 1220 to the fuel container 811 via the pump 1751 is exhausted via the gas-liquid separation membrane in the gas-liquid separation membrane chamber 815. 1743 is discharged. Further, an unreacted fuel gas generated from the fuel 124 in the fuel flow path 310 and an exhaust gas 1742 containing a by-product generated by an electrochemical reaction of the fuel cell are also passed through the gas-liquid separation membrane in the gas-liquid separation membrane chamber 815. It is discharged as exhaust gas 1743.

  Further, in the oxidant flow path 312, the exhaust gas 1745 containing a by-product generated by the electrochemical reaction of the fuel cell and the exhaust gas 1743 discharged through the gas-liquid separation membrane in the gas-liquid separation membrane chamber 815 are both It is collected and discharged as exhaust gas 1705 from the casing 1203 to the fuel cartridge 1220 via the pump 1757.

  In this manner, the exhaust gas 1705 generated in the housing 1203 is recovered in the recovery chamber 1703 of the fuel cartridge 1220, and the by-product contained in the exhaust gas 1705 is recovered in the recovery chamber 1703 as described in the above embodiment. The detoxified carbon dioxide is released to the outside of the fuel cell system 1740 through the fuel cartridge 1220. According to the fuel cell system 1740 of the present embodiment, not only the exhaust gas generated from the fuel electrode but also the exhaust gas generated from the oxidant electrode can be recovered, so that unreacted fuel gas or carbon dioxide crossing over to the oxidant electrode can be recovered. Carbon and its by-products can also be recovered.

  As described above, the by-product generated in the fuel cell is recovered with a simple configuration, and detoxified carbon dioxide is released to the outside of the battery, thereby improving the maintainability and reliability of the fuel cell system. Can do.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  For example, in the fuel cell system 1740 of FIG. 5, the fuel cell gas recovery system is provided between the discharge port of the fuel cell and the diaphragm 1709 of the recovery port 1707 of the fuel cartridge 1220 in FIG. An oxidation part that oxidizes the recovered exhaust gas can be included.

  Here, the oxidation unit may be a catalyst provided between the exhaust port of the fuel cell gas recovery system and the recovery port 1707 of the fuel cell cartridge 1220. Examples of the catalyst used here include Pt, Ti, Cr, Fe, Co, Ni, Cu, Zn, Nb, Mo, Ru, Pd, Ag, In, Sn, Sb, W, Au, Pb, and Bi. A metal, an alloy, or an oxide thereof containing at least one of the above can be used. These catalysts can oxidize exhaust gas efficiently.

  Further, the oxidation part may be provided with an oxidation promoting means for promoting the oxidation of the exhaust gas by the catalyst. The oxidation accelerating means can be configured to include, for example, a heating unit for heating a gas or a catalyst. In this way, it is possible to efficiently and reliably oxidize unreacted fuel gas and by-products contained in the exhaust gas before passing through the liquid in the recovery chamber 1703 of the fuel cartridge 1220. In addition, even after the fuel cell has been used for a long time, even if components that could not be oxidized by the catalyst or liquefied components adhered to the catalyst, such components would be oxidized efficiently and more reliably and completely. The performance can be maintained. In addition, the oxidation promoting means can have an oxygen supply part that supplies a gas containing oxygen.

  Further, the recovery chamber 1703 is preferably made of a material that forms a partition wall between the fuel chamber 1221 and has elasticity and stretchability and does not transmit the fuel 124 and the water 1701. According to the fuel cartridge 1220 configured as described above, it is possible to increase the volume of the recovery chamber 1703 as the amount of water 1701 in the recovery chamber 1703 increases due to the recovery of water generated during the operation of the fuel cell. Become.

  For example, when water generated at the oxidant electrode of the fuel cell is converted into water vapor and contained in the exhaust gas 1705 and recovered in the recovery chamber 1703, the volume of the water 1701 in the recovery chamber 1703 increases, and the water in the fuel chamber 1221 increases. Fuel 124 is used and the volume of fuel 124 decreases. If the portion constituting the partition wall between the fuel chamber 1221 and the recovery chamber 1703 is made of a material having elasticity and elasticity, the increase in the volume of the water 1701 can be slightly compensated by the decrease in the volume of the fuel 124. it can. Thereby, the volume of the whole fuel cartridge 1220 can be reduced. Alternatively, the amount of water 1701 accommodated in the recovery chamber 1703 can be reduced in advance in consideration of the increase in the water 1701 in the recovery chamber 1703 due to the recovery of the water generated during the operation of the fuel cell.

It is the figure which showed typically the structure of the cartridge for fuel cells which concerns on embodiment. It is sectional drawing which shows the attachment part of the cartridge for fuel cells. It is a figure which shows other embodiment of the cartridge for fuel cells. It is a figure which shows other embodiment of the cartridge for fuel cells. 1 is a block configuration diagram of a fuel cell system according to an embodiment.

Explanation of symbols

124 Fuel 126 Oxidant 310 Fuel channel 312 Oxidant channel 811 Fuel container 815 Gas-liquid separation membrane 831 Discharge channel 835 Catalyst 1000 Fuel cell group 1203 Case 1207 Fuel supply channel 1220 Fuel cartridge 1221 Fuel chamber 1223 Inlet 1245 Diaphragm 1257 Hollow needle 1701 Water 1703 Recovery chamber 1705 Exhaust gas 1707 Recovery port 1709 Separation membrane 1711 Gas-liquid separation membrane 1713 Exhaust port 1715 Gas adsorption filter 1717 Exhaust gas 1721 Exhaust gas recovery flow path 1723 Hollow needle 1725 Protrusion 1726 Spring 1727 Spring mounting portion 1729 Recess 1731 Air stone 1733 Air bubbles 1740 Fuel cell system 1741 Fuel gas 1742 Exhaust gas 1743 Exhaust gas 1745 Exhaust gas 1751 Pump 1753 Pump 1755 Pump 1757 Pump

Claims (12)

A fuel cell cartridge that is detachably attached to the fuel cell and supplies liquid fuel to the fuel cell,
A fuel supply port for supplying the liquid fuel to the fuel cell, and a fuel chamber for storing the liquid fuel;
An exhaust gas having an exhaust gas recovery port for recovering exhaust gas discharged from the fuel cell and a gas exhaust port for discharging the exhaust gas to the outside, and containing a liquid for dissolving a chemical substance contained in the exhaust gas inside A collection room;
A fuel cell cartridge comprising: The fuel cell cartridge according to claim 1, wherein
A fuel cell cartridge, wherein the liquid has a pH of 2 or more and 9 or less. The fuel cell cartridge according to claim 1 or 2,
The fuel cell cartridge, wherein the exhaust gas recovery port recovers exhaust gas discharged from an oxidant electrode of the fuel cell. The fuel cell cartridge according to any one of claims 1 to 3,
A cartridge for a fuel cell, wherein the exhaust gas is guided into the liquid. The fuel cell cartridge according to claim 4, wherein
A cartridge for a fuel cell, comprising a porous bubble foaming portion provided in the exhaust gas recovery port, wherein the exhaust gas is introduced as bubbles into the exhaust gas recovery chamber through the bubble foaming portion. The fuel cell cartridge according to any one of claims 1 to 5,
The interior of the exhaust gas recovery chamber is divided into two chambers, a chamber having the exhaust gas recovery port and a chamber having the gas exhaust port, by a gas-liquid separation membrane, and the liquid is supplied to the chamber having the exhaust gas recovery port. A cartridge for a fuel cell, characterized by being housed. The fuel cell cartridge according to any one of claims 1 to 6,
A fuel cell comprising a gas adsorption filter provided at the gas discharge port, wherein the exhaust gas that has passed through the gas-liquid separation membrane is discharged to the outside through the gas adsorption filter cartridge. The fuel cell cartridge according to any one of claims 1 to 7,
A cartridge for a fuel cell, comprising an oxidation part provided at the gas discharge port for oxidizing the exhaust gas that has passed through the gas-liquid separation membrane. The fuel cell cartridge according to any one of claims 1 to 8,
The cartridge for fuel cells, wherein the liquid is water. A fuel cell comprising a fuel electrode, an oxidant electrode and an electrolyte membrane sandwiched between them,
A fuel supply system for supplying liquid fuel to the fuel electrode;
A gas recovery system for recovering a gas generated at the fuel electrode or the oxidant electrode;
A fuel cell cartridge provided detachably with respect to the fuel supply system and the gas recovery system;
With
9. A fuel cell system, wherein the fuel cell cartridge is the fuel cell cartridge according to claim 1. The fuel cell system according to claim 10, wherein
An exhaust port for discharging the gas recovered by the gas recovery system;
A diaphragm provided to cover either the exhaust gas recovery port of the fuel cell cartridge or the exhaust port of the gas recovery system of the fuel cell, and a hollow needle provided on the other, When the cartridge is connected to the fuel cell, the hollow needle penetrates the diaphragm, and the exhaust gas recovery port and the exhaust port communicate with each other. The fuel cell system according to claim 11, wherein
An oxidation unit is provided between the exhaust port of the gas recovery system of the fuel cell and the exhaust gas recovery port of the fuel cell cartridge and oxidizes exhaust gas recovered by the gas recovery system of the fuel cell. A fuel cell system.

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