JP5773843B2 - Air secondary battery exterior material, method for producing air secondary battery exterior material, and air secondary battery - Google Patents

Description

  The present invention relates to an exterior material for an air secondary battery, a method for producing an exterior material for an air secondary battery, and an air secondary battery.

  As electronic devices such as video cameras, notebook computers, and mobile phones become more portable and smaller, there is an increasing demand for smaller and lighter batteries as driving sources, and high-performance lithium secondary batteries are widely used. Has reached. Recently, in order to apply a lithium secondary battery to an in-vehicle power source of an electric vehicle or a hybrid vehicle, an increase in the size of the lithium secondary battery has been studied.

  By the way, since the mounting space of the in-vehicle power source in the vehicle is limited and the shape of the mounting space is not constant, the lithium secondary battery for in-vehicle use is downsized (thinned) as in the case of electronic devices. There is also a need for weight reduction and freedom of shape. As an exterior material of such a lithium secondary battery, for example, an exterior sheet as disclosed in Patent Document 1 below is known. The exterior sheet of Patent Document 1 is formed by laminating an outer layer made of a resin layer, an inner layer made of an aluminum foil and a resin layer, and heat sealability is imparted to the inner resin layer. Lithium secondary battery with excellent hermeticity and freedom of shape by processing such an outer sheet into a bag shape to form a packaging container, inserting cells into the packaging container, and heat sealing the inner layers of the outer sheet. Is obtained.

  Recently, attention has been paid to an air secondary battery using lithium or aluminum as a negative electrode active material and oxygen in the air as a positive electrode active material. Since oxygen in the air is used as the positive electrode active material, an improvement in energy density per battery volume is expected. For example, a lithium-air secondary battery, which is a type of air secondary battery, has an exterior material in which metallic lithium as a negative electrode active material and an electrolyte are enclosed, and the exterior material is provided with a window for taking in oxygen. An air electrode is bonded to the part (see Patent Document 2). The air electrode is configured to include an oxygen permeable layer and a catalyst layer, and the air permeable layer is joined to the window portion of the exterior material, whereby the air electrode is disposed in the window portion. As the oxygen permeable layer, for example, a porous ceramic material is known. In addition, as an exterior material, adoption of a conventional exterior sheet for a lithium secondary battery has been studied.

Japanese Patent No. 4431822 JP 2011-96492 A

  However, in the conventional air secondary battery, the bonding between the outer sheet and the oxygen permeable layer made of the porous ceramic material is insufficient, and the leakage of the electrolyte or the infiltration of carbon dioxide from the outside Short life has been a problem.

  This invention is made | formed in view of the said situation, and it aims at providing the exterior material for air secondary batteries excellent in the adhesiveness of an exterior sheet and an oxygen permeable layer. Moreover, an object of this invention is to provide the manufacturing method of the exterior material for air secondary batteries which can improve the adhesiveness of an exterior sheet and an oxygen permeable layer. Furthermore, an object of the present invention is to provide an air secondary battery that can prevent leakage of electrolyte and intrusion of carbon dioxide from the outside.

[1] An oxygen capturing opening that is formed by laminating an outer layer including a heat-resistant resin film, a metal foil layer, and an inner layer including a thermoplastic resin film, and penetrates the outer layer, the metal foil layer, and the inner layer. An exterior sheet provided with,
A porous ceramic layer bonded to the inner layer side of the periphery of the opening so as to cover the opening, and
The porous outer portion or joint surface of one or both of the opening periphery of the ceramics layer, air secondary battery, characterized by the silane coupling agent having a reactive functional group is coated Exterior material.
[2] The reactive functional group of the silane coupling agent is selected from the group consisting of vinyl group, epoxy group, styryl group, methacryl group, acrylic group, amino group, ureido group, mercapto group, sulfide group, and isocyanate group. The packaging material for an air secondary battery according to [1], which has any one of the above at the end.
[3] The air secondary battery outer packaging material according to [1] or [2], wherein the inner layer is made of an acid-modified polyolefin resin film.
[4] The porous ceramic layer is a porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, porous oxidized alumina, ceramic particles or carbon particles and polymer particles kneaded. The packaging material for an air secondary battery according to any one of [1] to [3], which is any one selected from the group consisting of kneaded films.
[5] the the outer sheet and the porous ceramics layer, crimping or are bonded [1] to [4] air secondary battery exterior material according to any one of.
[6] on the porous ceramics layer, further, [1] a silane coupling agent is applied with a hydrophobic functional group to [5] exterior material for the air secondary cell according to any one of .
[7] An air secondary battery comprising the outer packaging material for an air secondary battery according to any one of [1] to [6].
[8] The outer layer including the heat-resistant resin film, the metal foil layer, and the inner layer including the thermoplastic resin film are laminated, and an opening for oxygen uptake that penetrates the outer layer, the metal foil layer, and the inner layer opening peripheral portion of the outer sheet which is provided, or the bonding surface of one or both of the outer edge of the porous ceramics layer, a step of applying a silane coupling agent having a reactive functional group ,
The opening periphery of the outer sheet, and joining the porous ceramics layer,
The manufacturing method of the exterior material for air secondary batteries characterized by comprising.
[9] The reactive functional group of the silane coupling agent is selected from the group consisting of vinyl group, epoxy group, styryl group, methacryl group, acrylic group, amino group, ureido group, mercapto group, sulfide group, and isocyanate group. The manufacturing method of the exterior material for air secondary batteries as described in [8] which has any 1 type by the terminal.
[10] The method for producing an exterior material for an air secondary battery according to [8] or [9], wherein the inner layer is made of an acid-modified polyolefin resin film.
[11] The porous ceramic layer is a porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, porous oxidized alumina, ceramic particles or carbon particles and polymer particles kneaded. The method for producing an exterior material for an air secondary battery according to any one of [8] to [10], which is any one selected from the group consisting of a kneaded film.
[12] The method for producing said and the outer sheet wherein the porous ceramics layer, pressure bonding or bonding to [8] to [11] outer casing material for the air secondary cell according to any one of.
[13] on the porous ceramics layer, it is coated with a silane coupling agent having a hydrophobic functional group, applying a silane coupling agent having a reactive functional group of the [8] to [12] The manufacturing method of the exterior material for air secondary batteries as described in any one.

According to an exterior material for use in an air secondary battery of the present invention, when bonding the inner layer and the porous ceramics layer comprising a thermoplastic resin film, on at least one reactive functional group of the inner layer or porous ceramics layer since a silane coupling agent having is applied, together with the bonding strength between the inner layer and the porous ceramics layer is improved, it is possible to increase the resistance to electrolyte.

Further, according to the air secondary battery of the present invention is provided with the inner layer and the porous ceramics layer and the air secondary battery exterior material bonding strength is improved, and leakage of the electrolyte, the carbon dioxide from the outside Can be prevented, and the life of the air secondary battery can be prevented from being shortened.

Furthermore, according to the manufacturing method of an air secondary battery exterior material of the present invention, when bonding the inner layer and the porous ceramics layer comprising a thermoplastic resin film, on at least one of the inner layer or the porous ceramics layer since applying the reactive functional group silane coupling agents having, together with the bonding strength between the inner layer and the porous ceramics layer is improved, it is possible to increase the resistance to electrolyte.

FIG. 1 is a perspective view showing an air secondary battery exterior material according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an air secondary battery exterior material according to an embodiment of the present invention. FIG. 3 is a partial cross-sectional view showing an exterior sheet constituting an exterior material for an air secondary battery according to an embodiment of the present invention. FIG. 4 is a partial cross-sectional view showing an example of an air secondary battery according to an embodiment of the present invention. FIG. 5 is a partial cross-sectional view showing another example of the air secondary battery according to the embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the drawings.
[Exterior material for air secondary battery]
As shown in FIGS. 1 and 2, an exterior sheet 1 for an air secondary battery (hereinafter referred to as an exterior material), which is a preferable aspect of the present embodiment, is an exterior sheet 2 provided with an opening 12 for oxygen uptake. And a porous ceramic layer 3 joined to the opening periphery 12a so as to cover the opening 12. As shown in FIG. 3, the exterior sheet 2 is a laminated body configured by laminating at least an outer layer 21, a metal foil layer 22, and an inner layer 23. In the example shown in FIG. 3, an adhesive layer 24 for laminating is provided between the metal foil layer 22 and the inner layer 23. The opening 12 for oxygen uptake is provided so as to penetrate the outer layer 21, the metal foil layer 22, the adhesive layer 24 and the inner layer 23. The porous ceramic layer 3 is bonded to the inner layer side of the exterior sheet 2.

  More specifically, the exterior sheet 2 is provided with an annular inclined portion 12b protruding to the outer layer side by pressing and an opening peripheral portion 12a connected to the inclined portion 12b. The opening 12 is an opening portion. It is surrounded by the peripheral part 12a. And the porous ceramic layer 3 is joined to the inner layer side of the opening peripheral part 12a over the perimeter of the opening peripheral part 12a. The porous ceramic layer 3 is larger than the opening 12, and the portion protruding from the opening 12 is the outer edge 3a of the porous ceramic layer 3, and this outer edge 3a is the inner layer side of the opening peripheral 12a. It is joined to.

In addition, the bonding surface of either or both of the outer edge portion 3a or the opening periphery 12a of the porous ceramics layer 3, over the entire circumference, a silane coupling agent having a reactive functional group is coated Yes. Further, the porous ceramics layer 3, silane treating agent having a hydrophobic functional group may be applied.

  As an aspect of bonding the porous ceramic layer 3 to the opening peripheral portion 12a, the opening peripheral portion 12a and the porous ceramic layer 3 may be pressure-bonded. An adhesive layer may be formed between them to bond them.

Further, the outer sheet 2 is provided with an annular inclined portion 12b and an opening peripheral portion 12a, and the porous ceramic layer 3 is bonded to the opening peripheral portion 12a, whereby a concave portion is formed on the inner layer side of the outer covering material 1. 1a is formed. The recess 1a accommodates a negative electrode, an air electrode, and the like of the air secondary battery.
Hereinafter, the constituent members of the exterior material 1 will be described in detail.

(Exterior sheet)
As described above, the exterior sheet 2 is configured by laminating the outer layer 21, the metal foil layer 22, and the inner layer 23. An adhesive layer 24 is interposed between the inner layer 23 and the metal foil layer 22. Further, an adhesive layer (not shown) is interposed between the outer layer 21 and the metal foil layer 22.

<Outer layer>
The outer layer 21 includes at least one or two or more heat resistant resin films. When the outer layer 21 is composed of two or more heat resistant resin films, the heat resistant resin films are preferably laminated with an adhesive layer interposed therebetween.

  The heat-resistant resin film constituting the outer layer 21 plays a role of ensuring moldability when the recess 1a is formed in the exterior material 1, and a stretched film of polyamide (nylon) resin or polyester resin is preferably used. The melting point of the heat-resistant resin film constituting the outer layer 21 is preferably higher than the melting point of the thermoplastic resin film constituting the inner layer 23. Thereby, it becomes possible to perform the heat seal of the exterior material 1 at the time of manufacturing an air secondary battery reliably.

  The thickness of the outer layer 21 is preferably about 10 to 50 μm, and more preferably about 15 to 30 μm. If the thickness is 10 μm or more, the stretch of the stretched film will not be insufficient when molding the outer packaging material 1, necking will not occur in the metal foil layer 22, and molding defects will not occur. Moreover, if thickness is 50 micrometers or less, the effect of a moldability can fully be exhibited.

<Metal foil layer>
The metal foil layer 22 plays the role of ensuring the barrier property of the exterior material 1, and aluminum foil, stainless steel foil, copper foil, etc. are used, but aluminum foil is used in consideration of formability and light weight. It is preferable to do. As the material of the aluminum foil, a pure aluminum-based or aluminum-iron-based alloy O material (soft material) is preferably used.

  The thickness of the metal foil layer 22 needs to be 20 to 80 μm in order to ensure workability and to ensure barrier properties that prevent oxygen and moisture from entering the air secondary battery. When the thickness is 20 μm or more, the metal foil layer 22 is not broken during the molding of the outer packaging material 1, and no pinhole is generated, so that intrusion of oxygen and moisture can be prevented. Moreover, if the thickness is 80 μm or less, the effect of improving the fracture during molding and the effect of preventing the occurrence of pinholes are maintained, and the total thickness of the exterior material 1 is not excessively increased, preventing an increase in weight, The volume energy density of the secondary battery can be improved.

  In addition, the metal foil layer 22 is subjected to an undercoat treatment with a silane coupling agent or a titanium coupling agent, a chromate treatment, or the like in order to improve the adhesion with the outer layer 21 and the inner layer 23 or to improve the corrosion resistance. A chemical conversion treatment should be performed.

<Inner layer>
Next, the inner layer 23 includes a thermoplastic resin film. As the thermoplastic resin film used for the inner layer 23, it plays a role of improving chemical resistance against an electrolyte for an air secondary battery having heat sealability and high corrosivity, and the metal foil layer 22 Those that can ensure insulation from the air electrode or negative electrode of the air secondary battery are good. For example, unstretched polyolefin films such as polypropylene and maleic acid-modified polypropylene, and unstretched films such as ethylene-acrylate copolymer or ionomer resin Is preferably used.
In particular, the inner layer 23 is preferably an acid-modified polyolefin film, more preferably a carboxylic acid-modified polyolefin film, such as maleic anhydride-modified polyethylene or maleic anhydride-modified polypropylene. By using an acid-modified polyolefin film for the inner layer 23 and applying a silane coupling agent to the inner layer 23 or the porous ceramic layer 3, the bonding strength of the porous ceramic layer 3 can be further increased.

  As thickness of the inner layer 23, the range of 0.1-200 micrometers is preferable, and the range of 50-100 micrometers is more preferable. If the thickness is 0.1 μm or more, preferably 50 μm or more, the heat seal strength is sufficient, the corrosion resistance to the electrolyte and the like is improved, and the insulation between the metal foil layer 22 and the negative electrode is enhanced. Moreover, if thickness is 200 micrometers or less, Preferably it is 100 micrometers or less, there is no trouble in heat-sealing property and chemical-resistance, and the volume energy density of an air secondary battery can be improved.

  Further, the thermoplastic resin film constituting the inner layer 23 may be composed of a single thermoplastic resin layer, but may be composed of a laminate of a plurality of thermoplastic resin layers. Specific examples of the inner layer composed of a plurality of thermoplastic resin layers include, for example, a three-layer film comprising an intermediate layer and a pair of coating layers laminated on both sides in the thickness direction of the intermediate layer with the intermediate layer interposed therebetween. it can.

  The melting point of the thermoplastic resin film constituting the inner layer 23 is preferably in the range of 130 ° C to 170 ° C, and more preferably in the range of 160 to 165 ° C. When the melting point is within this range, the heat resistance of the inner layer 23 is improved, the thickness of the inner layer 23 during heat sealing is not reduced, and the insulating property of the inner layer 23 is improved.

<Adhesive layer>
The adhesive layer 24 for laminating is disposed between the inner layer 23 and the metal foil layer 22 in order to bond the inner layer 23 and the metal foil layer 22. An adhesive layer is also disposed between the outer layer 21 and the metal foil layer 22.
The adhesive layer is preferably a dry laminate adhesive layer. For example, at least one selected from urethane-based, acid-modified polyolefin, styrene elastomer, acrylic-based, silicone-based, ether-based, and ethylene-vinyl acetate-based materials can be used. .

  The thickness of the adhesive layer is preferably in the range of 0.1 to 10 μm, and more preferably in the range of 1 to 5 μm. If the thickness of the adhesive layer is 0.1 μm or more, the adhesive strength does not decrease, and the insulation of the inner layer 23 can be further enhanced on the inner layer side. Moreover, if the thickness of an adhesive layer is 10 micrometers or less, the fall of adhesive strength can be prevented.

In particular, it is preferable to use adhesive layers made of different materials for the outer layer-side adhesive layer and the inner layer-side adhesive layer 24. As a combination of materials for the adhesive layer, a urethane adhesive is preferably used as the adhesive on the outer layer side when the outer layer 21 is made of PET or nylon, and an inner layer when the inner layer 23 is made of polypropylene or acid-modified polypropylene. An acrylic adhesive or an acid-modified olefin adhesive may be used as the side adhesive.
By using adhesive layers made of different materials as the outer-layer-side adhesive layer and the inner-layer-side adhesive layer 24, it is possible to impart adhesive strength and resistance to electrolytic solution between the materials.

  The inner layer 23 and the metal foil layer 22 may be laminated through the adhesive layer 24 as in the case of the outer layer 21, but a thermoadhesive resin excellent in chemical resistance and electrolytic solution resistance is used. In this case, better adhesion can be obtained between the inner layer 23 and the metal foil layer 22. In this case, a heat-adhesive resin such as maleic anhydride-modified polypropylene modified with maleic anhydride or the like is extruded between the metal foil layer 22 and the inner layer 23 and heat laminated. The method of heat laminating the metal foil layer 22 and the modified polypropylene and the inner layer and the polypropylene by using a polyolefin of the same type as the thermoplastic resin film of the inner layer 23, for example, a co-extruded resin of polypropylene and a modified polypropylene resin is costly. Is superior to.

(Porous ceramic layer)
The porous ceramic layer 3 allows oxygen to pass between the outside air and the air electrode of the air secondary battery. The thickness of the porous ceramic layer 3 is preferably in the range of 100 to 200 μm. The material of the porous ceramic layer 3 is, for example, porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, porous oxyalumina, ceramic particles or carbon particles and polymer particles. Any one selected from the group consisting of the porous kneaded films can be exemplified. Among these, porous alumina is particularly preferable.
Further, even if the material is not porous, an electron mixed conductive ceramic (perovskite oxide or the like) in which oxygen permeation occurs by ion exchange may be used. Examples of the ceramic particles constituting the porous kneaded film include porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, and porous anodic alumina. Furthermore, examples of the polymer particles include fluorine resins such as polytetrafluoroethylene, epoxy resins, silicon resins, and urethane resins.

(Silane coupling agent having a reactive functional group)
Reactive functional group silane coupling agent having a (hereinafter, referred to as silane coupling agent), a bonding surface of the opening peripheral portion 12a of the porous ceramics layer 3 of the outer edge portion 3a or the outer sheet 2 by reforming, improve the bonding strength between the porous ceramics layer 3 and the outer sheet 2. While the bonding surface of the porous ceramic layer 3 has polarity, the inner layer of the exterior sheet 2 has hydrophobicity and the surface properties are greatly different. Therefore, in order to improve the bonding strength, a silane coupling agent is used. Application is extremely effective. Bonding strength of the reactive functional groups of the silane coupling agent, terminal has a polar group, by which the polar group is bonded to the porous ceramic layer 3, a porous ceramics layer 3 and the outer sheet 2 Is thought to improve. In the case of joining by bonding the porous ceramics layer 3 and the outer sheet 2, the silane coupling agent may be applied to any of the porous ceramics layer 3 or the outer sheet 2.

Examples of the polar group at the end of the reactive functional group of the silane coupling agent include a vinyl group, an epoxy group, a styryl group, a methacryl group, an acrylic group, an amino group, a ureido group, a mercapto group, a sulfide group, and an isocyanate group. Any one selected from the group which can be illustrated.
In order to improve the bonding strength, the coated amount of the silane coupling agent is preferably to 0.1 mg / ^{m 2} or more 10000 mg / ^{m 2} or less in the range, 0.1 mg / ^{m 2} or more 100 mg / m A range of ² or less is more preferable, and a range of 0.5 mg / m ² or more and 1 mg / m ² or less is particularly preferable.

  Specific examples of the silane coupling agent include vinyl silane, methacryl silane, epoxy silane, mercapto silane, sulfur silane, amino silane, ureido silane, and isocyanate silane.

(Silane coupling agent having a hydrophobic functional group)
Further, in the outer package 1 is a preferred embodiment of the present embodiment, the joint surface of the porous ceramics layer 3 of the outer edge portion 3a or the outer sheet 2 opening peripheral portion 12a, a silane treating agent having a hydrophobic functional group (Hereinafter referred to as a hydrophobic silane treatment agent) may be applied. By applying a hydrophobic silane treatment agent, hydrophobic groups are introduced into the surface of the joint surface, which prevents moisture from entering the joint surface and into the air secondary battery via the joint portion. Intrusion of moisture can be suppressed and the bonding strength can be increased. It may also be coated with a hydrophobic silane treatment agents throughout the porous ceramics layer 3. Thereby, the penetration | invasion of the water | moisture content in an air secondary battery is suppressed.

Examples of the hydrophobic functional group of the hydrophobic silane treating agent include an alkyl group having 1 or more carbon atoms and having a cyclic, linear or branched chain.
The coating amount of the hydrophobic silane treatment agent is preferably to 0.1 mg / ^{m 2} or more 10000 mg / ^{m 2} or less in the range, be 0.1 mg / ^{m 2} or more 100 mg / ^{m 2} or less of the range More preferably, the range of 0.5 mg / m ^{2 to} 1 mg / m ² is particularly preferable.

  Specific examples of the hydrophobic silane treating agent include chlorosilane, alkoxysilane, silazane and the like.

(Adhesive layer)
Examples of the adhesive for bonding the porous ceramic layer 3 and the exterior sheet 2 by adhesion include, for example, a ethane series, an acid-modified polyolefin, a styrene elastomer, an acrylic series, a silicone series, an ether series, and an ethylene-vinyl acetate series. it can.

  In order to ensure sufficient adhesive strength, the thickness of the adhesive layer is preferably in the range of 0.05 μm to 100 μm, and more preferably in the range of 0.1 μm to 5 μm.

[Method of manufacturing exterior material for air secondary battery]
Next, the manufacturing method of the exterior material 1 is demonstrated.
A preferred manufacturing method of the outer package 1 is an aspect of this embodiment, the opening peripheral portion 12a of the outer sheet 2, or, in one or both bonding surfaces of either the outer edge 3a of the porous ceramics layer 3, silane a step of applying a coupling agent, composed of a step of bonding the porous ceramics layer 3 in the opening peripheral portion 12a of the outer sheet 2, from.
Further, before and after applying the silane coupling agent, the porous ceramics layer 3 may be coated with a hydrophobic silane treatment agent.

The step of coating a silane coupling agent, for example, the solvent to disperse the silane coupling agent as a dispersion, applying the dispersion to the outer edge portion 3a of the opening peripheral portion 12a or a porous ceramics layer 3 or, the dispersion was immersed outer sheet 2 or the porous ceramics layer 3, then carried out by heating the solvent is removed.

As the step of applying a hydrophobic silane treatment agent, for example, the solvent to disperse the hydrophobic silane treatment agent as a dispersion, or coating the dispersion into the porous ceramics layer 3, to the dispersion porous ceramics layer 3 is immersed, then carried out by heating the solvent is removed.

Order when applying both the porous ceramics layer 3 a silane coupling agent and a hydrophobic silane treatment agent may be performed in any of the first, but preferably, when applying a hydrophobic silane treatment agent previously good.

  Further, when a silane coupling agent or a hydrophobic silane treatment agent is applied to the porous ceramic layer 3, the application time or the immersion time is lengthened, so that the peripheral portion of the porous ceramic layer 3 is coated with the silane coupling agent. The pores may be blocked. In particular, the silane coupling agent can be uniformly applied by applying the silane coupling agent after closing the pores in the peripheral portion with the hydrophobic silane treatment agent.

Then, when performing bonding with the opening peripheral portion 12a and the porous ceramics layer 3 of the outer sheet 2 by thermocompression bonding, for example, a crimping start pressure and 0～4MPa, crimping pressure of 2 to 8 MPa, compression The temperature is preferably in the range of 70 to 220 ° C., and the pressure bonding time is preferably in the range of 10 seconds to 3 minutes. Crimping starting pressure With 0～4MPa, it can prevent cracking of the porous ceramics layer 3. Further, the bonding strength can be sufficiently increased by setting the pressure bonding pressure to 2 to 8 MPa, the pressure bonding temperature to 70 to 220 ° C., and the pressure bonding time to 10 seconds to 3 minutes.

Furthermore, bonding between the opening peripheral portion 12a and the porous ceramics layer 3 of the outer sheet 2, when performed by bonding, for example, be dried by applying an acrylic adhesive or an acid-modified olefin-based adhesive on the adhesive surface Can be adhered.

  4 and 5 show an air secondary battery using the above-described exterior material 1. The air secondary battery shown in FIGS. 4 and 5 is a lithium air secondary battery using lithium as a negative electrode active material.

  A lithium air secondary battery 31 shown in FIG. 4 includes an air electrode 32, a negative electrode 33, an electrolyte, and at least an exterior material 1 and 34 for packaging the air electrode 32, the negative electrode 33, and the electrolyte. The exterior material 1 is disposed on the air electrode 32 side, and the porous ceramic layer 3 bonded to the exterior material 1 is superimposed on the air electrode 32. The air electrode 32 is connected to the air electrode lead 32a. The air electrode lead 32a protrudes outside the exterior materials 1 and 34 as a positive electrode terminal. Further, the exterior material 34 is disposed on the negative electrode 33 side. The battery exterior material 34 is formed of the same laminate as the exterior sheet 2 constituting the exterior material 1. The outer peripheral portions 1b and 34b on the inner layer side of the outer packaging materials 1 and 34 are heat-sealed with each other to form a substantially bag shape. The air electrode 32, the negative electrode 33, and the electrolyte are inserted between the exterior materials 1 and 34 and are disposed in the recess 1 a of the exterior material 1. Moreover, a separator is arrange | positioned between the air electrode 32 and the negative electrode 33 as needed.

  The air electrode 32 is configured by laminating a catalyst layer and an oxygen diffusion layer. The oxygen diffusion layer diffuses oxygen that has permeated through the opening 12 and the porous ceramic layer 3 over the entire surface of the catalyst layer. The catalyst layer takes in oxygen and causes an electrode reaction.

  The negative electrode 33 is made of, for example, a metal lithium foil. The negative electrode 33 is pressure-bonded to a current collector 35 made of metal or the like. The current collector 35 is connected to the negative electrode lead 36. The negative electrode lead 36 protrudes outside the exterior materials 1 and 34 as a negative electrode terminal.

  When the lithium air secondary battery 31 shown in FIG. 4 is manufactured, the outer packaging materials 1 and 34 are prepared and heat-sealed to form a bag body, and the current collector 35 and the negative electrode lead 36 are integrated with the negative electrode 33. The separator 33 and the air electrode 32 are superimposed on the negative electrode 33, and the negative electrode 33, the separator, and the air electrode 32 are inserted into the recess 1a of the outer package 1 from the opening of the bag body, and finally the electrolyte is injected. The lithium air secondary battery 31 is obtained by heat-sealing the opening.

5 includes at least an air electrode 42, a negative electrode 43, an electrolyte, an air electrode 42, a negative electrode 43, and an exterior material 1, 1 for packaging the electrolyte. Yes.
In the example shown in FIG. 5, current collectors 45, 45, negative electrodes 43, 43 made of metal lithium foil, and air electrodes 42, 42 are sequentially stacked on both surfaces of the negative electrode lead 46. In addition, the air electrode leads 42a are overlapped and heat-sealed so as to sandwich the air electrode lead 42a.

  When the lithium air secondary battery 41 shown in FIG. 5 is manufactured, the outer packaging materials 1 and 1 are prepared and heat-sealed to form a bag body, and the current collector 45 and the negative electrode lead 46 are integrated with the negative electrode 43. The separator 43 and the air electrode 42 are superposed on the negative electrode 43, and the negative electrode 43, the separator, and the air electrode 42 are inserted into the recesses 1a and 1a of the exterior materials 1 and 1 from the opening of the bag body, and finally the electrolyte is injected. Lithium-air secondary battery 41 is obtained by heat-sealing the opening after liquid.

  In the examples shown in FIGS. 4 and 5, the lithium air secondary battery has been described as an example. However, the present invention is not limited to this, and is applied to, for example, an aluminum air secondary battery in which the negative electrode active material is aluminum. Also good.

As described above, according to the preferred air secondary battery outer package 1 is an aspect of this embodiment, when joining the inner layer 23 and the porous ceramics layer 3 comprising a thermoplastic resin film, the inner layer 23 or because on at least one silane coupling agent of the porous ceramics layer 3 is applied, together with the bonding strength between the inner layer 23 and the porous ceramics layer 3 is improved, it is possible to increase the resistance to electrolyte.
Moreover, further to the porous ceramics layer 3, by hydrophobic silane treatment agent is applied, the permeation of moisture in the porous ceramic layer 3 can be prevented. Moreover, it prevents the adhesion of moisture to the hydrophobic porous ceramics layer 3 of the outer edge portion 3a, to further improve the bonding strength between the inner layer 23 and the porous ceramics layer 3 with a hydrophobic silane treatment agent Can do.

Further, according to the air secondary battery which is a preferred aspect of this embodiment, since the bonding strength is provided with the outer package 1 air secondary battery having improved between the inner layer 23 and the porous ceramics layer 3, the electrolyte Leakage and intrusion of carbon dioxide from the outside can be prevented, and the life of the air secondary battery can be prevented from being shortened.

Furthermore, according to the preferred method of the outer package 1 air secondary cell is an aspect of this embodiment, when joining the inner layer 23 and the porous ceramics layer 3 comprising a thermoplastic resin film, the inner layer 23 or since applying the porous on at least one silane coupling agent of ceramics layer 3, together with the bonding strength between the inner layer 23 and the porous ceramics layer 3 is improved, it is possible to increase the resistance to electrolyte.
Moreover, further to the porous ceramics layer 3, by applying a hydrophobic silane treatment agent, while preventing the permeation of moisture in the porous ceramic layer 3, the bonding strength between the inner layer 23 and the porous ceramics layer 3 It can be improved.

Example 1
As the porous ceramic layer, a commercially available porous alumina substrate (size: 5 cm × 3 cm × 1 mm, porosity: 0.35, average pore size: 100 nm) was prepared.

The porous ceramic layer was hydrophobized. First, hexadecylchlorosilane (hydrophobic silane treating agent): toluene (solvent) = 10: 100 is mixed at a mass ratio to form a mixed solution, and the porous ceramic layer is immersed in this mixed solution. Heated for hours. Thereafter, excess hexadecylchlorosilane and residual toluene were removed by washing with toluene and vacuum drying. By this operation, a bulky functional group (hexadecyl group) was added to the surface of the porous ceramic layer, and hydrophobicity was expressed. The coating amount was 1 mg / m ² .

Next, a silane coupling agent was applied to the outer edge portion of the porous ceramic layer subjected to the hydrophobization treatment and an exterior sheet as shown in FIG. First, a silane coupling agent solution was prepared. The silane coupling agent solution was prepared by diluting an epoxy-based silane coupling agent having a reactive functional group whose end is an epoxy group (Z-6043, manufactured by Dowcorning) to 1% and 5% with ethanol. And using the brush, the silane coupling agent solution was apply | coated to the outer edge part of a porous ceramic layer, and the inner layer side of the opening peripheral part of an exterior sheet. After coating, drying was performed in an oven at 60 ° C. for 1 minute to remove the solvent (ethanol) used for dilution. The coating amount was 1 mg / m ² .

Then, after removing the solvent, the ceramic layer and the exterior sheet were pressure-bonded using a heat sealer. The pressure bonding conditions were such that the outer layer side of the exterior sheet was 200 ° C., the inner layer side was 100 ° C., the seal pressure was 9 kgf / cm ² (0.88 MPa), and the seal time was 1 minute. Thus, the exterior material was manufactured.

(Example 2)
An exterior material was produced in the same manner as in Example 1 except that 3-aminopropyltriethoxysilane (hereinafter referred to as APS) manufactured by Aldrich was used as the silane coupling agent.

(Comparative Example 1)
An exterior material was produced in the same manner as in Example 1 except that the porous alumina substrate was not subjected to surface treatment with a silane coupling agent and a hydrophobic silane treatment agent.

(Example 3)
An exterior material of Example 3 was produced in the same manner as in Example 1 except that the above-described chlorosilane hydrophobization was not performed.

About the obtained exterior material, peeling strength of a ceramic layer and an exterior sheet was evaluated. As conditions, the peel strength was evaluated after the exterior material was immersed in water for 24 hours and after it was immersed in an electrolyte solution for 24 hours, in addition to the condition where no stress was applied. The peel strength was measured based on JIS K 6854-2 under the condition that the ceramic layer was fixed. That is, the exterior sheet to which the ceramic layer was bonded was cut to a width of 15 mm and evaluated by performing a peel test between the ceramic layer and the exterior sheet. In addition, ion-exchanged water was used for immersion in water, and an electrolytic solution in which 1 mol / L LiPF ₆ was dissolved in a mixed solvent of ethylene carbonate: diethyl carbonate = 1: 1 (volume ratio) was used as the nonaqueous electrolytic solution. The results are shown in Table 1.

  As shown in Table 1, the performance with the silane coupling agent was not significantly reduced as compared with the case without the silane coupling agent.

In addition, as shown in FIG. 4, the outer packaging material 1 and the outer packaging material 34 are heat sealed to each other to produce a bag body, and the bag body is filled with a nonaqueous electrolyte solution to which a staining solution is added and sealed. Prepared and evaluated the presence or absence of leakage.
The electrolyte solution was dyed by using 1 wt% rhodamine B ethanol solution and adding 1 vol% of the electrolyte solution. As the electrolytic solution, an electrolytic solution in which 1 mol / L LiPF ₆ was dissolved in a mixed solvent of ethylene carbonate: diethyl carbonate = 1: 1 (volume ratio) was used. The results are shown in Table 2. No leakage of the electrolyte was confirmed even after 30 days for those having a silane coupling agent. In contrast, in Comparative Example 1, liquid leakage occurred in one day. In Example 3, the generation of gas caused by moisture intrusion occurred, and the internal pressure increased and the container expanded slightly.

1 ... air secondary battery exterior material, 2 ... outer sheet, 3 ... outer edge of the porous ceramic layer, 3a ... porous ceramics layer, 12 ... opening, 12a ... opening peripheral portion, 21 ... outer layer 22 ... metal foil layer, 23 ... inner layer, 31, 41 ... air secondary battery.

Claims (13)

An outer layer containing a heat-resistant resin film, a metal foil layer, and an inner layer containing a thermoplastic resin film are laminated, and an opening for oxygen uptake is provided through the outer layer, the metal foil layer, and the inner layer. An exterior sheet,
A porous ceramic layer bonded to the inner layer side of the periphery of the opening so as to cover the opening, and
The porous outer portion or joint surface of one or both of the opening periphery of the ceramics layer, air secondary battery, characterized by the silane coupling agent having a reactive functional group is coated Exterior material.   The reactive functional group of the silane coupling agent is any selected from the group consisting of vinyl group, epoxy group, styryl group, methacryl group, acrylic group, amino group, ureido group, mercapto group, sulfide group, and isocyanate group. The packaging material for an air secondary battery according to claim 1, which has at least one type thereof.   The exterior material for an air secondary battery according to claim 1 or 2, wherein the inner layer is made of an acid-modified polyolefin resin film.   The porous ceramic layer is made of porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, porous oxyalumina, ceramic particles or a porous kneaded film in which carbon particles and polymer particles are kneaded. The exterior material for an air secondary battery according to any one of claims 1 to 3, wherein the exterior material is any one selected from the group consisting of: Wherein the outer sheet and the porous ceramics layer, crimping or air secondary battery exterior material according to any one of claims 1 to 4 is bonded. Wherein the porous ceramics layer, further, an air secondary battery exterior material according to any one of claims 1 to 5 silanizing agent having a hydrophobic functional group is applied.   An air secondary battery comprising the exterior member for an air secondary battery according to any one of claims 1 to 6. An outer layer containing a heat-resistant resin film, a metal foil layer, and an inner layer containing a thermoplastic resin film are laminated, and an opening for oxygen uptake is provided through the outer layer, the metal foil layer, and the inner layer. an opening peripheral portion of the outer sheet are or, in one or both bonding surfaces of either the outer edge of the multi-porous ceramics layer, a step of applying a silane coupling agent having a reactive functional group,
The opening periphery of the outer sheet, and joining the porous ceramics layer,
The manufacturing method of the exterior material for air secondary batteries characterized by comprising.   The reactive functional group of the silane coupling agent is any selected from the group consisting of vinyl group, epoxy group, styryl group, methacryl group, acrylic group, amino group, ureido group, mercapto group, sulfide group, and isocyanate group. The manufacturing method of the exterior material for air secondary batteries of Claim 8 which has such 1 type in the terminal.   The method for producing a packaging material for an air secondary battery according to claim 8 or 9, wherein the inner layer is made of an acid-modified polyolefin resin film.   The porous ceramic layer is made of porous alumina, porous titania, porous zirconia, porous silica, porous zeolite, porous oxyalumina, ceramic particles or a porous kneaded film in which carbon particles and polymer particles are kneaded. The method for producing a packaging material for an air secondary battery according to any one of claims 8 to 10, which is any one selected from the group consisting of: Wherein a and outer sheet wherein the porous ceramics layer, the manufacturing method of the outer package for the air secondary cell according to any one of claims 8 to 11 crimps or adhesion. Wherein the porous ceramics layer, are coated with the silane treating agent having a hydrophobic functional group, any one of claims 8 to 12 for coating a silane coupling agent having a reactive functional group of the The manufacturing method of the exterior material for air secondary batteries as described in 1 ..

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