JP5968686B2 - Selective oxygen permeable substrate, positive electrode for air battery and air battery - Google Patents

Description

  The present invention relates to a selective oxygen permeable substrate, a positive electrode for an air battery, and an air battery. More specifically, the present invention relates to a selective oxygen permeable substrate that can selectively introduce oxygen in the air and has high resistance to an electrolytic solution. The present invention also relates to an air battery positive electrode provided with the selective oxygen permeable substrate and an air battery provided with the air battery positive electrode.

  Since an air battery uses a metal as a negative electrode active material and oxygen as a positive electrode active material, the discharge capacity per “unit mass of the positive electrode active material” is extremely large. In recent years, there has been a demand for higher capacity and higher output of batteries in electric vehicles and portable devices, and high performance of air batteries is expected.

  As described above, since the positive electrode active material of the air battery is oxygen, oxygen in the air can be used as the positive electrode active material. However, if air is directly introduced into the air battery, carbon dioxide in the air is also introduced. Since carbon dioxide may react with the electrolytic solution used in the air battery and deteriorate the battery performance, it is desirable not to introduce it into the air battery. Thus, when oxygen in the air is used as the positive electrode of the air battery, carbon dioxide, which is preferably not introduced into the positive electrode of the air battery, is also supplied to the air battery.

  In order to solve such a problem, a method of removing carbon dioxide from air supplied to an air battery has been studied (for example, see Patent Document 1).

  On the other hand, oxygen selective permeable membranes (oxygen-enriched membranes) in which magnetic particles are dispersed, which can concentrate oxygen contained in the air, have been studied (see, for example, Patent Document 2).

JP 10-99629 A JP 2007-237138 A

  In the air battery described in Patent Document 1, a gas separator including a ferrite magnet and stainless steel is used as an apparatus for selectively permeating oxygen. Therefore, it is assumed that the air battery as a whole has a large volume and mass.

  In addition, the oxygen-enriched film described in Patent Document 2 uses a silicone film. In an organic polymer film such as silicone, gas permeation is performed by a dissolution / diffusion mechanism derived from a flexible molecular chain, so that dissolution of carbon dioxide into the film cannot be suppressed. Therefore, if a silicone-based membrane is used as a membrane for oxygen concentration when oxygen in the air is used as the positive electrode active material of an air battery, sufficient oxygen concentration is required to dissolve carbon dioxide in the membrane. It is assumed that it cannot be done. In addition, it is assumed that the silicone film does not have sufficient resistance to the electrolyte used in the air battery.

  The present invention has been made in view of the above-described problems. That is, an object of the present invention is to provide a selective oxygen permeable substrate that can selectively introduce oxygen in the air and has high resistance to an electrolytic solution. Furthermore, it aims at providing the positive electrode for air batteries provided with the said selective oxygen permeable base | substrate, and the air battery provided with the said positive electrode for air batteries.

[1] and the magnetic material-dispersed layer to which the magnetic material is dispersed as a main component of carbon, and a porous substrate, wherein the magnetic material-dispersed layer, have a gas introduction surface for introducing gas therein the material of the porous substrate, Ru ceramic der, selective oxygen permeable substrate.

[2] The selective oxygen permeable substrate according to [1], wherein the magnetic material dispersion layer is obtained by dispersing a magnetic material in a porous carbon film.

[ 3 ] A positive electrode for an air battery comprising the selective oxygen permeable substrate according to [1] or [2] .

[ 4 ] The air battery positive electrode according to [ 3 ], further comprising an air battery catalyst supported on the selective oxygen permeable substrate.

[ 5 ] A positive electrode, a negative electrode using a metal as a negative electrode active material, and an electrolyte solution interposed between the positive electrode and the negative electrode, wherein the positive electrode is for an air battery according to [ 3 ] or [ 4 ] An air battery that is a positive electrode.

  According to the selective oxygen permeable substrate of the present invention, since it has a “magnetic material dispersion layer in which carbon is a main component and in which a magnetic material is dispersed”, oxygen, which is a paramagnetic material, is affected by the magnetic field formed by the magnetic material. Can be selectively introduced (incorporated) into the selective oxygen permeable substrate. On the other hand, molecules such as carbon dioxide and water that are not paramagnetic substances can be excluded. Further, the magnetic material dispersion layer is mainly composed of carbon, which has a rigid molecular structure and has a strong resistance to acids and alkalis. Therefore, when the selective oxygen permeable substrate is used for a positive electrode for an air battery, the positive electrode for an air battery has high resistance to an electrolytic solution.

  According to the positive electrode for an air battery of the present invention, since the selective oxygen permeable substrate of the present invention is provided, oxygen in the air can be selectively introduced into the positive electrode for the air battery (in the selective oxygen permeable substrate). it can. Moreover, since the positive electrode for air batteries of this invention is equipped with the selective oxygen permeable base | substrate of the said invention, it has high tolerance with respect to electrolyte solution.

  According to the air battery of the present invention, since the air battery positive electrode of the present invention is used as a positive electrode, oxygen in the air can be selectively introduced into the air battery positive electrode (selective oxygen permeable substrate). . Moreover, since the air battery of this invention uses the said positive electrode for air batteries of this invention as a positive electrode, it has high tolerance with respect to electrolyte solution.

It is a schematic diagram which shows the cross section of one Embodiment of the selective oxygen permeation | transmission base | substrate of this invention. It is a schematic view showing a cross section of another embodiment of a selection択的oxygen transmissive substrates. It is a schematic diagram which shows the cross section of one Embodiment of the air battery of this invention.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the following embodiments. It should be understood that modifications and improvements as appropriate to the following embodiments are also included in the scope of the present invention based on ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. It is.

(1) Selective oxygen permeable substrate:
As shown in FIG. 1, an embodiment of the selective oxygen permeable substrate of the present invention has a magnetic material dispersion layer 2 in which a magnetic material 3 is mainly composed of carbon, and the magnetic material dispersion layer 2 is It has a gas introduction surface 5 for introducing gas into the interior. FIG. 1 is a schematic view showing a cross section of an embodiment of the selective oxygen permeable substrate of the present invention.

  As described above, the selective oxygen permeable substrate of the present embodiment has “a magnetic material dispersion layer in which carbon is a main component and a magnetic material is dispersed”. Therefore, oxygen, which is a paramagnetic substance, can be selectively introduced (taken in) into the selective oxygen permeable substrate under the influence of a magnetic field formed by the magnetic substance. At this time, oxygen is taken into the selective oxygen permeable substrate from the gas introduction surface. In addition, since the magnetic material dispersion layer is mainly composed of carbon, when the selective oxygen permeable substrate of this embodiment is used for an air battery positive electrode, the air battery positive electrode And has high resistance. Further, when the selective oxygen permeable substrate of this embodiment is used for a positive electrode for a fuel cell, the same effect can be obtained.

  In the selective oxygen permeable substrate 1 of the present embodiment, as shown in FIG. 1, a “porous carbon film in which a magnetic material is dispersed” (magnetic material dispersed layer 2) is disposed on a porous substrate 6. It is a thing. Therefore, the magnetic material dispersion layer is also porous. A selective oxygen permeable substrate 1 is formed by the magnetic material dispersion layer 2 and the porous substrate 6. Therefore, the entire selective oxygen permeable substrate 1 is porous. “Porous” means that at least oxygen can permeate. The magnetic substance dispersion layer 2 is a porous carbon film in which a magnetic substance is dispersed, but may have other elements. Further, the selective oxygen permeable substrate 1 has the magnetic material dispersion layer 2 and the porous substrate 6, but may have other elements.

  The selective oxygen permeable substrate 1 of the present embodiment introduces (takes in) oxygen in the air from the gas introduction surface 5 of the magnetic material dispersion layer 2. The oxygen introduced into the magnetic material dispersion layer 2 passes through the magnetic material dispersion layer 2 and moves into the porous substrate 6. Therefore, when the selective oxygen permeable substrate 1 of the present embodiment is used as a base material (component) of a positive electrode for an air battery, oxygen in the air can be efficiently supplied to the positive electrode of the air battery. In this case, a positive electrode reaction (for example, a reaction between lithium ions and oxygen) is caused in the porous substrate 6.

  The magnetic material dispersion layer 2 is mainly composed of carbon. Here, “consisting mainly of carbon” means that the carbon content is 50% by mass or more in the components excluding the magnetic substance. As components other than carbon, oxygen, nitrogen, hydrogen, metal elements, and the like may be contained. The magnetic material dispersion layer 2 is mainly composed of carbon. Therefore, when the selective oxygen permeable substrate 1 of this embodiment is used as a component of the positive electrode for an air battery, it is possible to prevent the positive electrode for an air battery from being deteriorated by the electrolytic solution.

  The shape of the magnetic material dispersion layer 2 is not particularly limited, but for example, a plate shape, a film shape, a sheet shape, a film shape, a rod shape, a tube shape, a monolith shape and the like are preferable. When the magnetic material dispersion layer 2 is plate-shaped, the gas introduction surface 5 has “a pair of parallel surfaces (front surface and back surface)” having the maximum area in the “plate” (for example, a pair of parallel plates when the “plate” is a rectangular parallelepiped. It is preferable that it is one side in (side). Further, when the magnetic material dispersion layer 2 is in the form of a film, a sheet, or a film, one side of the “film, sheet, or film” (one side of a pair of parallel surfaces (front surface and back surface)) Preferably there is.

  The thickness of the magnetic material dispersion layer 2 (distance from the gas introduction surface 5 to the other parallel surface) is preferably 0.1 to 1000 μm, and more preferably 0.5 to 100 μm. If the thickness is less than 0.1 μm, defects such as pinholes may occur, and the effect of selectively taking in oxygen may be reduced. If it is thicker than 1000 μm, it may be difficult for oxygen to move to the porous substrate 6. Further, the area of the gas introduction surface 5 of the magnetic material dispersion layer 2 is not particularly limited, and can be appropriately determined according to the application.

  The average pore diameter of the magnetic material dispersion layer 2 (porous carbon film) is preferably 0.3 to 5 nm, and more preferably 0.4 to 1 nm. If it is smaller than 0.3 nm, the oxygen uptake speed may decrease because of the proximity to the oxygen molecular diameter. If it is larger than 5 nm, the effect of selectively taking in oxygen may be reduced because it is sufficiently larger than the oxygen molecular diameter.

  The magnetic substance 3 contained in the magnetic substance dispersion layer 2 in the present invention indicates a magnetized ferromagnetic substance or ferrimagnetic substance. The type of magnetic material is not particularly limited as long as it has spontaneous magnetization even without an external magnetic field. Specific examples of the magnetic material include iron oxide, metallic iron, an alloy containing iron, a rare earth magnet, a ferrite magnet, and magnetite. The magnetic material is preferably magnetic particles. The average particle diameter of the magnetic particles is preferably 0.01 to 10 μm, and more preferably 0.1 to 5 μm. If it is smaller than 0.01 μm, the magnetic force of the magnetic material may be insufficient. If it is larger than 10 μm, the mechanical strength of the magnetic material dispersion layer 2 may be lowered.

  It is preferable that the magnetic substance 3 is uniformly dispersed in the magnetic substance dispersion layer 2. The content of the magnetic material 3 contained in the magnetic material dispersion layer 2 is preferably 1 to 90% by mass, but the content can be appropriately adjusted depending on the strength of the magnetic force of the magnetic material. If it is less than 1% by mass, the effect of selectively taking in oxygen may be reduced. If it is more than 90% by mass, the mechanical strength of the magnetic material dispersion layer 2 may be lowered.

In selecting択的oxygen transmissive substrates 1, as the material of the porous substrate 6 (material), a ceramic, an inorganic oxide, inorganic nitride, at least an inorganic carbide, glass, is selected from the group consisting of carbon, and metal 1 Preferably it is a seed. In the selective oxygen permeable substrate 1 of the present embodiment, the material (material) of the porous substrate 6 is ceramic. As the ceramic, silica, titania, alumina, or zirconia is preferable. As the metal, stainless steel or noble metal is preferable. By using at least one material selected from the group consisting of ceramic, inorganic oxide, inorganic nitride, inorganic carbide, glass, carbon, and metal as the material, the selective oxygen permeable substrate 1 of this embodiment is used for an air battery. When used as a component of the positive electrode, it is possible to prevent the positive electrode for an air battery from being deteriorated by the electrolytic solution. Moreover, when the material of the porous substrate 6 is carbon or metal, the porous substrate 6 becomes conductive. Therefore, when the selective oxygen permeable substrate 1 of this embodiment is used as a component of the positive electrode for an air battery, the conductivity of the positive electrode is ensured. When the porous substrate 6 is made of ceramic and the selective oxygen permeable substrate 1 of this embodiment is used as a component of the positive electrode for an air battery, the ceramic is used to ensure the conductivity of the positive electrode. A conductive member may be combined.

  The porous substrate 6 is preferably disposed (laminated) on a surface parallel to the gas introduction surface 5 of the magnetic material dispersion layer 2 (a surface located behind the gas introduction surface 5).

  Although it does not specifically limit as a shape of the porous base material 6, For example, plate shape, film | membrane shape, sheet shape, film shape, rod shape, tube shape, monolith shape, etc. are preferable.

  The thickness of the porous substrate 6 is preferably 0.1 to 500 μm, more preferably 1 to 100 μm, and particularly preferably 2 to 50 μm. When the thickness is less than 0.1 μm, when the selective oxygen permeable substrate 1 of the present embodiment is used as a component of the positive electrode for an air battery, the discharge capacity of the air battery may be reduced. If the thickness is greater than 500 μm, oxygen introduced through the magnetic material dispersion layer 2 and introduced into the porous substrate 6 may be difficult to be supplied to the entire porous substrate 6. The “thickness of the porous substrate 6” is located on the back side of the “bonding surface A” from the surface bonded to the magnetic material dispersion layer 2 (sometimes referred to as “bonding surface A”). It is the distance to the surface. Further, the area of the “joining surface A” of the porous substrate 6 is not particularly limited, and can be appropriately determined according to the application.

  The selective oxygen permeable substrate of this embodiment may further have a water repellent layer (water repellent layer) (not shown). The selective oxygen permeable substrate of the present embodiment has a water-repellent layer, thereby preventing water from entering inside or leaking outside. As a result, when the selective oxygen permeable substrate of the present embodiment is used as the base material (component) of the positive electrode for an air battery, it is possible to prevent the influence of water on the positive electrode for the air battery.

  The material of the water repellent layer is preferably a fluororesin or the like. The water repellent layer may be disposed on the gas introduction surface side of the porous substrate (magnetic dispersion layer), or may be disposed between the magnetic dispersion layer and the porous substrate. . When the water repellent layer is disposed on the gas introduction surface side of the magnetic material dispersion layer, the gas introduction surface is not exposed to the outside. The gas introduction surface may be exposed to the outside or may not be exposed to the outside. The shape of the water repellent layer is preferably a plate shape, a film shape, a sheet shape, a film shape, a rod shape, or the like. The thickness of the water repellent layer is not particularly limited as long as water permeation can be suppressed.

Selection択的oxygen permeability substrate, as shown in FIG. 2, a main component of carbon entire selective oxygen permeable substrate, the entire selective oxygen permeable substrate may be a magnetic material-dispersed layer 2. Figure 2 is a schematic view showing a cross section of another embodiment of a selection択的oxygen transmissive substrates (selective oxygen permeable substrate 21).

Thus, selection択的oxygen transmissive substrates 21 are those overall selective oxygen permeable substrate is mainly composed of carbon. Therefore, the entire selective oxygen permeable substrate 21 becomes conductive, and when the selective oxygen permeable substrate 21 is used as a positive electrode for an air battery, it is not necessary to add a conductive member or the like. Moreover, since carbon can function as a catalyst for an air battery by selecting a structure, when the selective oxygen permeable substrate 21 is used as a positive electrode for an air battery, the amount of catalyst supported can be reduced. . Furthermore, you may have a catalyst layer, such as manganese dioxide, as needed.

Selection択的the oxygen transmission substrate 21, since the magnetic body 3 is dispersed throughout selectively oxygen transmission substrate, it is possible to improve the selective capture effect of oxygen.

Selection択的oxygen transmission substrate 21 (distributed across the magnetic body 3 is selectively oxygen transmissive substrates) whole with its primary component a carbon entirely of a magnetic material dispersion layer 2. The selective oxygen permeable substrate 21 of the present embodiment is preferably the same as the selective oxygen permeable substrate 1 of the above-described embodiment of the present invention except for this.

(2) Method for producing selective oxygen permeable substrate:
Next, a method for producing an embodiment of the selective oxygen permeable substrate of the present invention (selective oxygen permeable substrate 1 (see FIG. 1)) will be described.

  The selective oxygen permeable substrate of the present embodiment is preferably produced by first producing a porous substrate and then disposing a magnetic material dispersion layer on one surface of the porous substrate.

(2-1)
Although it does not specifically limit as a manufacturing method of a porous base material, For example, the following methods are preferable.

  When the material of the porous substrate 6 is ceramic, first, a forming raw material containing a powdered ceramic raw material is prepared. As the ceramic raw material, those preferred as the material (material) of the porous substrate in the embodiment of the selective oxygen permeable substrate of the present invention are preferable. It is preferable to prepare a slurry-like forming raw material by mixing a ceramic raw material with a binder, a pore former, a plasticizer, a dispersant, a dispersion medium, and the like as necessary. Next, the obtained slurry-like forming raw material is formed into a sheet to form a green sheet for a porous substrate. It is preferable to obtain a porous substrate by drying, degreasing and then firing the obtained green sheet. Alternatively, the ceramic powder raw material can be formed into a block shape using a mold or the like and sintered in an electric furnace or the like, and then a sheet-like porous substrate can be obtained by cutting or the like.

  When the material of the porous substrate 6 is made of carbon, for example, a powdery or fibrous carbon raw material (amorphous carbon, graphite, carbon nanotube, fullerene, mesoporous carbon, etc.) is prepared. And it is preferable to produce a slurry-like forming raw material by mixing the carbon raw material with a binder, a pore former, a plasticizer, a dispersant, a dispersion medium and the like, if necessary. Next, it is preferable that the obtained slurry-shaped molding raw material is molded into a sheet to obtain a porous substrate. As another production method, it is also preferable to obtain a porous substrate by carbonizing a polymer raw material that has been molded into a sheet. Or after carbonizing block-shaped resin, such as a polyimide resin and a phenol resin, a sheet-like porous base material can also be obtained by cutting.

  When the material of the porous substrate 6 is made of metal, for example, it is preferable to form a powdery or fibrous metal raw material into a sheet and then sinter it to obtain a porous substrate. As another manufacturing method, it is also preferable to obtain a porous substrate by subjecting the foamed resin to metal plating treatment and heat treatment. Furthermore, as another production method, it is also preferable to form a porous metal substrate by forming a fibrous metal raw material into a mesh shape. Alternatively, it is possible to obtain a sheet-like porous substrate by cutting or the like after the metal powder is formed into a block shape by a mold or the like and sintered in an electric furnace or the like. Alternatively, a porous substrate can be obtained by anodic oxidation of aluminum or the like.

  Each condition in the production process can be appropriately determined so that a desired porous substrate is obtained.

(2-2)
The method for disposing the magnetic material dispersion layer on one surface of the porous substrate is as follows.

  Next, a magnetic material dispersion layer is laminated on the porous substrate to produce a selective oxygen permeable substrate. For example, a raw material solution is prepared by mixing a polymer material that is a raw material of the porous carbon film and magnetic particles in a solvent. And it is preferable to coat | cover a raw material solution by methods, such as a dip coat, a spin coat, a drip coat, a spray coat, and a filtration coat, on a porous base material, and obtain a coating body. Next, it is preferable that the obtained coated body is dried and carbonized by heat treatment in a vacuum or in an inert atmosphere to obtain a selective oxygen permeable substrate. The magnetic material may be magnetized in advance, or may be magnetized after obtaining a selective oxygen permeable substrate.

(2-3)
The method for producing the selective oxygen permeable substrate 21 of the present invention shown in FIG. 2 is as follows.

  For example, first, a raw material solution is prepared by mixing a polymer material as a raw material for a porous carbon film and magnetic particles in a solvent. And it is preferable to cast a raw material solution on plates, such as Teflon (trademark), and to obtain a sheet-like molded object. Next, the obtained sheet-like molded body is dried and peeled from a plate such as Teflon (registered trademark). Thereafter, the dried sheet-like molded body is preferably carbonized by heat treatment in vacuum or in an inert atmosphere to obtain a selective oxygen permeable substrate. Alternatively, a magnetic powder can be dispersed in a varnish-like polyimide resin or a phenol resin, solidified into a block shape, carbonized, and then a sheet-like porous substrate can be obtained by cutting or the like. The magnetic material may be magnetized in advance, or may be magnetized after obtaining a selective oxygen permeable substrate.

(3) Positive electrode for air battery:
One embodiment of the positive electrode for an air battery of the present invention comprises one embodiment of the selective oxygen permeable substrate of the present invention (selective oxygen permeable substrate 1 (see FIG. 1)). Moreover, it is preferable that the positive electrode 10 for air batteries (refer FIG. 3) of this embodiment is further equipped with the catalyst for air batteries carry | supported by the selective oxygen permeation | transmission base | substrate.

  The positive electrode for an air battery according to this embodiment includes one embodiment of the selective oxygen permeable substrate of the present invention (selective oxygen permeable substrate 1 (see FIG. 1)). Therefore, the positive electrode for an air battery of the present embodiment can selectively introduce oxygen in the air into the positive electrode for an air battery (in a selective oxygen permeable substrate). Moreover, since the positive electrode for air batteries of this invention is equipped with the selective oxygen permeable base | substrate of the said invention, it has high tolerance with respect to electrolyte solution.

  The air battery catalyst is preferably supported on a porous substrate. Further, it may be carried on the magnetic material dispersion layer.

As an air battery catalyst, manganese-containing compounds, Au, Co ₃ O ₄ , NiO, Fe ₂ O ₃ , Pt, Pd, RuO ₂ , CuO, V ₂ O ₅ , MoO ₃ , Y ₂ O ₃ , carbon Etc. can be used. Among these, a compound containing manganese is particularly preferable, and a manganese oxide is more preferable. Examples of the manganese oxide include manganese dioxide (α-MnO ₂ , β-MnO _{2 and the} like).

  In the positive electrode for an air battery of the present embodiment, a conductive member may be disposed in order to improve the conductivity. As the conductive member, one made of carbon or metal can be used.

(4) Air battery:
As shown in FIG. 3, one embodiment of the air battery of the present invention includes a positive electrode 11, a negative electrode 12 using metallic lithium as a negative electrode active material, and an electrolyte solution 13 interposed between the positive electrode 11 and the negative electrode 12. Is provided. And the air battery 100 of this embodiment WHEREIN: The positive electrode 11 is the positive electrode 10 for air batteries of this invention. FIG. 3 is a schematic view showing a cross section of one embodiment (air battery 100) of the air battery of the present invention.

  Since the air battery of this embodiment uses one embodiment of the positive electrode for an air battery of the present invention as the positive electrode, oxygen in the air is selectively introduced into the positive electrode for the air battery (in a selective oxygen permeable substrate). Can do. Moreover, since the air battery of this invention uses the said positive electrode for air batteries of this invention as a positive electrode, it has high tolerance with respect to electrolyte solution.

  As shown in FIG. 3, in the air battery 100 of this embodiment, the positive electrode 11 has one surface (electrolyte introduction surface 11b) in contact with the electrolyte solution 13 and the other surface (air introduction surface 11a) in contact with air. It is preferable that they are arranged as described above. In addition, when the water repellent layer is arrange | positioned on the surface of the air introduction surface 11a, it is preferable to arrange | position so that the surface of a water repellent layer may contact air. Here, the gas introduction surface 5 of the magnetic material dispersion layer of the selective oxygen permeable substrate becomes the air introduction surface 11a of the positive electrode of the air battery. The “one surface” and the “other surface” of the positive electrode 11 are, for example, “surfaces” of the plate, film, sheet, film, etc. when the positive electrode 11 is plate-shaped, film-shaped, sheet-shaped, film-shaped, etc. And “back side” are preferable.

  In the air battery 100 of the present embodiment, the electrolytic solution 13 is a non-aqueous electrolytic solution, an aqueous electrolytic solution, or a combination of both (rather than mixing, a plurality of layers are formed via a separator or the like). Is preferred. As the electrolytic solution, a known one can be used.

  The air battery 100 of the present embodiment may include a separator (not shown) between the positive electrode and the negative electrode. The separator is not particularly limited as long as it is a material that can withstand the use of an air battery.

  As shown in FIG. 3, in the air battery 100 of the present embodiment, the positive electrode 11, the negative electrode 12, and the electrolytic solution 13 are stored in a protector 16 and further disposed in an air battery container (casing) 14. Is. The protector 16 for directly storing a battery structure composed of a positive electrode, a negative electrode, an electrolytic solution and the like is preferably insulated by a material having no conductivity. The shape of the protector 16 can be a desired shape. As shown in FIG. 3, the shape of the protector 16 is such that the periphery of the positive electrode 11, the negative electrode 12, and the electrolytic solution 13 is isolated (hermetically sealed) to ensure insulation, and the air introduction surface 11a of the positive electrode 11 is provided. Furthermore, it is preferable that the outside air (air) is supplied. For example, as shown in FIG. 3, it is preferable that the air introduction surface 11a of the positive electrode 11 has a shape that can be exposed to the outside. The air battery container (casing) 14 disposed in the protector 16 for the purpose of further mechanical strength and protection from water or the like is preferably made of a rigid material such as metal. Further, the thickness of the air battery container 14 can be appropriately determined according to the size of the air battery. In the air battery 100 of the present embodiment, it is preferable that the current collector 15 is disposed on each of the positive electrode 11 and the negative electrode 12. Moreover, it is preferable that the air battery container 14 has a shape such that, for example, the air introduction surface 11a of the positive electrode 11 is exposed to the outside as shown in FIG. However, the surface of the air introduction surface 11a can be protected by a mesh, a plate with a hole, or the like as long as it has a shape to which outside air (air) is supplied.

Example 1
A barium ferrite (magnetic body) powder having an average particle diameter of about 1 μm is added to a polyamic acid solution having a polyamic acid concentration of 10% by mass using N-methyl-2-pyrrolidone (NMP) as a solvent, and a polyamic acid solution-magnetic body is added. A mixture was obtained. And the raw material solution for film-forming was produced by stirring the obtained polyamic-acid solution-magnetic substance mixture for 24 hours. U-Varnish-A (trade name) manufactured by Ube Industries, Ltd. was used as the polyamic acid solution. Moreover, 5 mass parts of barium ferrite powder was added with respect to 100 mass parts of polyamic acid. The obtained raw material solution was applied onto a porous alumina plate (porous substrate), dried by heating at 150 ° C. for 60 minutes, and then imidized by heating at 250 ° C. for 30 minutes (a polyimide film was obtained). ) The above steps from application to heating were repeated 3 times in total. Thereafter, the porous alumina plate was heat-treated at 800 ° C. in a vacuum box furnace to carbonize the polyimide film obtained by the imidization. As a result, a “carbon film in which barium ferrite was dispersed” having a film thickness of about 1 μm was obtained. The obtained carbon film was magnetized by applying a magnetic field of 1 Tesla so that the magnetic flux direction was perpendicular to the porous alumina plate. As a result, a selective oxygen permeable substrate having a selective oxygen permeable membrane disposed on the surface of the porous substrate was obtained.

  The resulting selective oxygen permeable substrate was subjected to a “gas permeation test” by the following method. The obtained results are shown in Table 1.

(Gas permeation test)
Dry air is supplied at 100 cm ³ / min to one side of the membrane disposed on the porous substrate. And the component of the gas (permeate gas) which permeate | transmitted the film | membrane and flowed out to the other surface side is analyzed by a gas chromatography, and the oxygen concentration of permeate gas is calculated | required.

(Comparative Example 1)
A laminate in which a carbon film was disposed on the surface of a porous substrate was prepared in the same manner as in Example 1 except that a raw material solution for film formation was prepared without adding barium ferrite powder. The thickness of the film was 1 μm.

  It can be seen from Table 1 that the film containing the magnetic substance functions as a selective oxygen permeable film. It can also be seen that the film not containing a magnetic substance does not have a function of selectively transmitting oxygen.

  The selective oxygen permeable substrate of the present invention can be suitably used as a positive electrode substrate of an air battery. The air battery of the present invention can be suitably used in industries where batteries are used, such as the electric vehicle industry.

1, 2: 1: Selective oxygen permeable substrate, 2: Magnetic dispersion layer, 3: Magnetic material, 5: Gas introduction surface, 6: Porous substrate, 10: Positive electrode for air battery, 11: Positive electrode, 11a: Air introduction Surface, 11b: electrolyte introduction surface, 12: negative electrode, 13: electrolyte, 14: air battery container, 15: current collector, 16: protector, 100: air battery, A: bonding surface.

Claims (5)

A magnetic material dispersion layer in which a magnetic material is mainly composed of carbon, and a porous substrate ;
The magnetic material-dispersed layer, have a gas introduction surface for introducing gas therein,
The material of the porous substrate, Ru ceramic der, selective oxygen permeable substrate.   2. The selective oxygen permeable substrate according to claim 1, wherein the magnetic material dispersion layer is a porous carbon film in which a magnetic material is dispersed. The positive electrode for air batteries provided with the selective oxygen permeable base | substrate of Claim 1 or 2 . The positive electrode for an air battery according to claim 3 , further comprising an air battery catalyst supported on the selective oxygen permeable substrate. A positive electrode;
A negative electrode using a metal as a negative electrode active material;
An electrolyte solution interposed between the positive electrode and the negative electrode,
An air battery, wherein the positive electrode is the positive electrode for an air battery according to claim 3 or 4 .

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