WO2016047642A1

WO2016047642A1 - Gas diffusion layer to be used in battery, membrane electrode assembly to be used in battery and using gas diffusion layer to be used in battery, member to be used in battery, battery, and method for producing same

Info

Publication number: WO2016047642A1
Application number: PCT/JP2015/076803
Authority: WO
Inventors: 仁司大谷
Original assignee: 大日本印刷株式会社
Priority date: 2014-09-25
Filing date: 2015-09-18
Publication date: 2016-03-31

Abstract

By providing a first conductive porous layer containing a conductive carbon material and a modified polyolefin resin, it is possible to provide a gas diffusion layer to be used in a battery and which suppresses crushing of the pores in the conductive porous layer and exhibits strong adhesion between a separator and a conductive porous substrate.

Description

Battery gas diffusion layer, battery membrane-electrode assembly using battery gas diffusion layer, battery member, battery, and production method thereof

The present invention relates to a gas diffusion layer for a battery, a membrane-electrode assembly for a battery using the gas diffusion layer for a battery, a battery member, a battery, and a method for producing them.

Electrochemical cells that use gas for gas reactions such as fuel cells and metal-air cells are equipped with a gas diffusion layer in order to improve their battery performance.

For example, a membrane-electrode assembly (MEA) constituting a polymer electrolyte fuel cell usually has a structure in which a gas diffusion layer, a catalyst layer, an electrolyte membrane, a catalyst layer, and a gas diffusion layer are sequentially laminated. .

For this gas diffusion layer, a conductive porous substrate such as carbon paper or carbon cloth is generally used. Further, for the purpose of improving the water management characteristics such as conductivity, gas diffusivity, gas permeability, smoothness, water discharge and retention of the conductive porous substrate, the conductive porous substrate is As a support, a conductive porous layer containing a conductive carbon material (carbon black or the like), a polymer (fluorine resin) or the like may be formed on the conductive porous substrate.

Conventional conductive porous layers are usually coated with a conductive porous layer-forming composition on a conductive porous substrate such as carbon paper or carbon cloth, and then dried to form a conductive porous layer. Therefore, there is a possibility that the paste composition may permeate from the surface of the conductive porous substrate and block the voids of the conductive porous substrate (for example, Patent Document 1).

On the other hand, a method of laminating a conductive porous layer formed in advance using a substrate film or the like on a conductive porous substrate is also known.

JP 2001-351537 A

However, when a large amount of fluororesin is used as the high molecular polymer of the conductive porous layer, it is necessary to laminate under high temperature and high pressure conditions in order to ensure adhesion with the conductive porous substrate. There was a possibility that the voids of the conductive porous layer would be crushed. When the voids in the conductive porous layer are crushed, the battery performance is adversely affected.

This also applies to the case where the conductive porous layer is used as a gas diffusion layer and incorporated into a battery without using a conductive porous substrate. Specifically, in order to improve workability before incorporating into a battery. When the conductive porous layer is integrated with the separator, the pores of the conductive porous layer may be crushed.

Therefore, the main object of the present invention is to provide a battery gas diffusion layer that suppresses collapse of voids in the conductive porous layer and has high adhesion to the conductive porous substrate and the separator.

As a result of intensive studies in view of the above problems, the present inventor has included a modified polyolefin resin in at least one conductive porous layer constituting the gas diffusion layer for a battery, so that the voids of the conductive porous layer are included. It was found that a gas diffusion layer for a battery having high adhesion to a conductive porous substrate or a separator can be provided. The present invention has been completed based on such findings. That is, the present invention includes the following configurations.
Item 1. A gas diffusion layer for a battery, comprising a first conductive porous layer containing a conductive carbon material and a modified polyolefin resin.
Item 2. Item 2. The battery gas diffusion layer according to Item 1, wherein a second conductive porous layer containing a conductive carbon material and a polymer is laminated so as to be in contact with the first conductive porous layer.
Item 3. Item 3. The battery gas diffusion layer according to Item 2, wherein the polymer contained in the second conductive porous layer is a fluororesin.
Item 4. Item 4. The battery gas diffusion layer according to any one of Items 1 to 3, wherein the first conductive porous layer further contains a curing agent.
Item 5. Item 5. The battery gas diffusion layer according to any one of Items 1 to 4, wherein a conductive porous substrate is laminated so as to be in contact with the first conductive porous layer.
Item 6. Item 5. The gas diffusion layer for a battery according to any one of Items 1 to 4 is provided on the one or both sides of a catalyst layer-electrolyte membrane laminate in which a catalyst layer, an electrolyte membrane, and a catalyst layer are sequentially laminated. A membrane-electrode assembly for a battery, wherein the layers are laminated so that the outermost layer is the outermost layer.
Item 7. The gas diffusion layer for a battery according to Item 5, wherein the conductive porous substrate is the outermost layer on one or both sides of a catalyst layer-electrolyte membrane laminate in which a catalyst layer, an electrolyte membrane, and a catalyst layer are sequentially laminated. The membrane-electrode assembly for a battery is laminated as described above.
Item 8. Item 8. A battery in which a separator is further laminated so as to be in contact with the first conductive porous layer or the conductive porous substrate which is the outermost layer of the membrane-electrode assembly for a battery according to Item 6 or 7.
Item 9. Item 9. The battery according to Item 8, wherein the separator has a porous region.
Item 10. Item 9. The battery according to Item 8, wherein the separator has no gas flow path and includes a porous body.
Item 11. Item 5. A battery member, wherein a separator is laminated so as to be in contact with the first conductive porous layer of the battery gas diffusion layer according to any one of Items 1 to 4.
Item 12. Item 12. The battery member according to Item 11, wherein the separator has a porous region.
Item 13. Item 12. The battery member according to Item 11, wherein the separator has no gas flow path and includes a porous body.
Item 14. A method for producing a gas diffusion layer for a battery, comprising:
(I) a step of forming a first conductive porous layer on a substrate using a conductive carbon material and a first conductive porous layer-forming composition containing a modified polyolefin resin; and (II) The manufacturing method of the gas diffusion layer for batteries provided with the process of peeling a base material from a 1st electroconductive porous layer.
Item 15. Furthermore, after the step (II),
(III) A second conductive porous layer is formed on the first conductive porous layer using a second conductive porous layer forming composition containing a conductive carbon material and a polymer. Item 15. The method for producing a battery gas diffusion layer according to Item 14, comprising a step.
Item 16. Furthermore, between the step (I) and the step (II),
(III) A second conductive porous layer is formed on the first conductive porous layer using a second conductive porous layer forming composition containing a conductive carbon material and a polymer. Item 15. The method for producing a battery gas diffusion layer according to Item 14, comprising a step.
Item 17. further,
(IV) The method for producing a gas diffusion layer for a battery according to item 14 or 15, comprising a step of laminating a conductive porous substrate so as to be in contact with the first conductive porous layer.
Item 18. Furthermore, after the step (II),
(IV) The method for producing a gas diffusion layer for a battery according to item 16, comprising a step of laminating a conductive porous substrate so as to be in contact with the first conductive porous layer.
Item 19. (1) A step of preparing a gas diffusion layer for a battery including at least a first conductive porous layer by the manufacturing method according to any one of Items 14 to 16, and (2) a separator comprising the first conductive porous layer The manufacturing method of the member for batteries provided with the process laminated | stacked so that a quality layer may be contact | connected.

According to the present invention, since the gas diffusion layer for a battery includes the first conductive porous layer containing the modified polyolefin resin, the conductive porous layer is prevented from collapsing the voids of the conductive porous layer. Adhesiveness with a base material or a separator can be improved.

It is drawing explaining the structure of the gas diffusion layer for batteries of this invention which has a 1st electroconductive porous layer. It is drawing explaining the structure of the gas diffusion layer for batteries of this invention which has a 1st conductive porous layer and a 2nd conductive porous layer. It is drawing explaining the structure of the gas diffusion layer for batteries of this invention which has a 1st conductive porous layer and a conductive porous base material. It is drawing explaining the structure of the gas diffusion layer for batteries of this invention which has a 2nd conductive porous layer, a 1st conductive porous layer, and a conductive porous base material in this order. It is drawing explaining the structure of the battery member of this invention which has a 1st electroconductive porous layer and a separator. It is drawing explaining the structure of the battery member of this invention which has a 2nd conductive porous layer, a 1st conductive porous layer, and a separator in this order. Battery membrane-electrode assembly of the present invention (catalyst layer-battery membrane in which the second conductive porous layer and the first conductive porous layer are laminated in this order on both surfaces of the electrolyte membrane laminate- It is drawing explaining an electrode assembly. One aspect of the battery membrane-electrode assembly of the present invention (the second conductive porous layer, the first conductive porous layer, and the conductive porous substrate are arranged in this order on both sides of the catalyst layer-electrolyte membrane laminate) 1 is a drawing for explaining a laminated battery membrane-electrode assembly). One aspect of battery of the present invention (battery in which a second conductive porous layer, a first conductive porous layer, a conductive porous substrate, and a separator are laminated in this order on both sides of a catalyst layer-electrolyte membrane laminate. Is a drawing for explaining.

Hereinafter, specific embodiments of the present invention will be described. In the present specification, “integrating” or “adhering” the first conductive porous layer and the conductive porous substrate or separator means that the first conductive porous layer is positioned below. In this case, it means that the first conductive porous layer is adhered to the conductive porous substrate or the separator so as not to peel off for 5 minutes or more. When adhered to this degree, the first conductive porous layer can be easily handled and workability can be improved, and peeling from the conductive porous substrate or separator during battery operation can be prevented.

1. Battery gas diffusion layer 1
As shown in FIG. 1, the battery gas diffusion layer of the present invention is a battery gas diffusion layer including a first conductive porous layer 11 containing a conductive carbon material and a modified polyolefin resin. The battery gas diffusion layer 1 of the present invention is a layer different from a catalyst layer described later.

(1-1) First conductive porous layer 11
In the present invention, the first conductive porous layer 11 contains a conductive carbon material and a modified polyolefin resin. In the present invention, the battery gas diffusion layer 1 includes the first conductive porous layer 11 (particularly, a layer in contact with the conductive porous substrate or the separator). It is possible to integrate them while preventing the gaps from being crushed. The first conductive porous layer 11 can be formed on a base material using, for example, a first conductive porous layer forming composition containing a conductive carbon material and a modified polyolefin resin. The thickness of the first conductive porous layer 11 is usually about 1 μm to 300 μm, and preferably about 5 μm to 250 μm, for example. When the thickness of the 1st electroconductive porous layer 11 is less than 1 micrometer, when using together the electroconductive porous base material which has the function which supports the electroconductive porous layer mentioned later, an electroconductive porous base material The catalyst layer and the electrolyte membrane may be damaged due to the influence of the uneven shape due to the surface roughness. Moreover, when thickness exceeds 300 micrometers, while gas diffusibility falls, resistance becomes large and can cause a battery performance fall. From the viewpoint of space saving, the thickness of the first conductive porous layer 11 is preferably 250 μm or less.

Conductive carbon material Examples of the conductive carbon material include conductive carbon particles and conductive carbon fibers.

[Conductive carbon particles]
The conductive carbon particles are not particularly limited as long as they are conductive carbon materials, and known or commercially available materials can be used. Examples thereof include carbon black such as channel black, furnace black, ketjen black, acetylene black and lamp black; graphite; activated carbon and the like. These can be used alone or in combination of two or more. By containing these conductive carbon particles, the conductivity of the battery gas diffusion layer can be improved.

When carbon black is used as the conductive carbon particles, the average particle size (arithmetic average particle size) of carbon black is usually about 5 nm to 200 nm, particularly preferably about 5 nm to 100 nm. When carbon black aggregates are used, the thickness is preferably about 10 nm to 600 nm, particularly about 50 nm to 500 nm. When graphite, activated carbon, or the like is used, the average particle size is preferably about 500 nm to 100 μm, particularly about 1 μm to 80 μm. The average particle diameter of the conductive carbon particles is specified by 20 arithmetic average particle diameters based on an electron microscope observation image.

The average particle diameter (arithmetic average particle diameter) of the conductive carbon particles increases the relatively fine pore volume in the first conductive porous layer 11, and the gas permeation performance, smoothness, water discharge and retention, etc. In the case of imparting water management characteristics, it is usually about 5 nm to 200 nm, and particularly preferably about 5 nm to 100 nm. In addition, when the first conductive porous layer 11 is provided with a function of gas diffusion characteristics, the average is preferably about 5 μm to 100 μm, more preferably about 6 μm to 80 μm.

[Conductive carbon fiber]
By blending the conductive carbon fiber, not only the occurrence of cracks on the coating surface of the first conductive porous layer forming composition can be suppressed, but also a highly strong sheet-like first conductive porous layer 11 is produced. It is also possible to do. Examples of the conductive carbon fiber used in the first conductive porous layer 11 include vapor grown carbon fiber (VGCF (registered trademark)), carbon nanotube, carbon nanocup, and carbon nanowall. Other conductive carbon fibers having a relatively large average fiber diameter include PAN (polyacrylonitrile) -based carbon fibers (carbon fibers using PAN as a raw material), pitch-based carbon fibers (carbon fibers using pitch as a raw material), etc. Can also be used.

The average fiber diameter of the conductive carbon fiber increases the relatively fine pore volume in the first conductive porous layer 11 and gives water management characteristics such as gas permeation performance, smoothness, water discharge and retention. In this case, about 50 nm to 800 nm, particularly about 100 nm to 250 nm is preferable. In this case, for example, the average fiber length is preferably about 4 μm to 500 μm, particularly about 4 μm to 300 μm, more preferably about 4 μm to 50 μm, particularly about 10 μm to 20 μm. The average aspect ratio is preferably about 5 to 600, particularly about 10 to 500. The fiber diameter, fiber length, and aspect ratio of the conductive carbon fiber are measured by an image measured with a scanning electron microscope (SEM) or the like.

In addition, when the first conductive porous layer 11 is provided with a function of gas diffusion characteristics by forming a relatively large pore diameter, the average fiber diameter of the conductive carbon fiber is about 5 μm to 20 μm, particularly 6 μm. It is preferably about 15 μm. In this case, for example, the average fiber length is preferably about 5 μm to 1 mm, particularly about 10 μm to 600 μm. The average aspect ratio is preferably about 2 to 50, and more preferably about 2 to 40. Also in this case, the fiber diameter, fiber length, and aspect ratio of the conductive carbon fiber are measured by an image measured with a scanning electron microscope (SEM) or the like.

Modified polyolefin resin In the present invention, it is easy to integrate with a conductive porous substrate or a separator even under weak conditions (low temperature and low pressure conditions), and is excellent in heat resistance, chemical resistance, water repellency and the like. In addition, the first conductive porous layer 11 contains a modified polyolefin resin. Moreover, when the modified polyolefin resin is contained in the first conductive porous layer 11, the first conductive porous layer 11 is easily peeled from the base material in the step (II) described later. For this reason, when it peels from a base material after forming the 1st electroconductive porous layer 11 on a base material, the 1st electroconductive porous layer 11 remains on a base material, a film | membrane cracks, or a crack generate | occur | produces Can be suppressed. Furthermore, the self-supporting property can be maintained even after the first conductive porous layer 11 is peeled from the substrate.

The polyolefin resin constituting the modified polyolefin resin is a resin containing an olefin component of 50 mol% or more, particularly 80 mol% or more of the whole resin. Examples of the olefin component include ethylene, propylene, isobutylene, 1-butene, 1 Examples thereof include olefins having 2 to 6 carbon atoms such as pentene and 1-hexene, and mixtures thereof may be used. Among these, olefins having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene and 1-butene are preferable, and ethylene and propylene are more preferable. The polyolefin resin constituting the modified polyolefin resin is not a fluororesin from the viewpoint of further suppressing the collapse of the voids of the conductive porous layer and further improving the adhesion with the conductive porous substrate or the separator. It is preferable. Similarly, the modified polyolefin resin preferably does not contain fluorine. The polyolefin resin constituting the modified polyolefin resin may be a homopolymer composed of the above-described components, or a copolymer composed of two or more of the above-described components. When the polyolefin resin constituting the modified polyolefin resin is a copolymer, it may be a random copolymer or a block copolymer, and may be either crystalline or amorphous. Furthermore, the polyolefin resin constituting the modified polyolefin resin may be composed of a single polyolefin resin or may be composed of two or more kinds of polyolefin resins.

As the type of modification of the modified polyolefin resin, dispersibility is improved by acid modification, a uniform first conductive porous layer 11 is obtained, and good performance as the conductive porous layer is obtained. In the invention, it is preferable to use an acid-modified polyolefin resin. As such an acid-modified polyolefin resin, a carboxylic acid-modified polyolefin resin is preferable. Examples of the compound (acid) used for modification include unsaturated carboxylic acids such as (meth) acrylic acid, maleic acid, itaconic acid, fumaric acid and crotonic acid, and salts, acid anhydrides and esters (unsaturated). In the case of a dicarboxylic acid, a derivative such as a half ester) or an amide (in the case of an unsaturated dicarboxylic acid, particularly a half amide) may be used. Of these, acrylic acid or its ester, methacrylic acid or its ester, (maleic anhydride) and the like are preferable, and acrylic acid or its ester and maleic anhydride are more preferable. Moreover, the unsaturated carboxylic acid should just be copolymerized in polyolefin resin, and the form is not limited. The acid-modified polyolefin resin to be used may be a polyolefin resin modified with a single compound (acid) among these compounds (acids) or a polyolefin resin modified with two or more compounds (acids). These acid-modified polyolefin resins are not particularly limited, and known or commercially available materials can be used. Moreover, these acid-modified polyolefin resins may be used alone or in combination of two or more. In the present invention, “(meth) acrylic acid” means “acrylic acid” or “methacrylic acid”. Further, “(maleic anhydride)” means “maleic acid” or “maleic anhydride”.

As the modified polyolefin resin, in addition to the acid-modified polyolefin resin described above, a chlorinated polyolefin resin, a modified polyolefin resin having an alcoholic hydroxyl group, and the like can also be used. The modified polyolefin resin having an alcoholic hydroxyl group is not particularly limited, and examples thereof include a modified polyolefin resin having at least one alcoholic hydroxyl group in the polyolefin main chain. The number of hydroxyl groups bonded to the polyolefin main chain is not particularly limited. For example, a preferable range of the hydroxyl value that is an index of polarity in the polymer is, for example, about 20 to 60 (mgKOH / g), more preferably about 30 to 50 (mgKOH / g). The hydroxyl value is measured according to the method defined in JIS K1557-1. The modified polyolefin resin having an alcoholic hydroxyl group preferably has a hydroxyl group at the end of the polyolefin main chain. The modified polyolefin resin should not contain fluororesin-modified polyolefin from the viewpoint of further suppressing the collapse of the voids of the conductive porous layer and further improving the adhesion to the conductive porous substrate or separator. Is preferred.

The ratio of the compound (acid, etc.) used for modification in the modified polyolefin resin makes it easier to integrate the first conductive porous layer with the conductive porous substrate or separator, as well as heat resistance, From the viewpoint of further improving chemical properties and water repellency, the amount is preferably about 0.1 to 40% by mass, more preferably about 0.1 to 30% by mass. The ratio of the compound (acid etc.) used for modification in the modified polyolefin resin is measured by ¹ H-NMR analysis.

The weight average molecular weight of the modified polyolefin resin makes it easier to integrate the first conductive porous layer with the conductive porous substrate or separator, and further improves heat resistance, chemical resistance, water repellency, etc. In view of the above, about 6000 to 200000 is preferable, and about 8000 to 150,000 is more preferable. The weight average molecular weight of the modified polyolefin resin is a value measured by gel permeation chromatography (GPC) measured under conditions using polystyrene as a standard sample. In addition, the melting point of the modified polyolefin resin makes it easier to integrate the first conductive porous layer with the conductive porous substrate or separator, and further improves heat resistance, chemical resistance, water repellency, etc. In view of the above, each is preferably about 60 to 160 ° C., more preferably about 70 to 140 ° C. In the present invention, the melting point of the modified polyolefin resin refers to an endothermic peak temperature in differential scanning calorimetry.

The method for modifying the polyolefin resin is not particularly limited as long as the compound (acid or the like) used for modification is copolymerized with the polyolefin resin. Examples of such copolymerization include random copolymerization, block copolymerization, and graft copolymerization (graft modification), and graft copolymerization is preferable.

In the present invention, the first conductive porous layer 11 can contain a polymer other than the modified polyolefin resin.

As such a polymer, known or commercially available materials can be used. Specifically, ion conductive polymer resin, polyvinyl alcohol resin, polyvinyl acetate resin, styrene-acrylic copolymer resin, styrene-vinyl acetate copolymer resin, ethylene-vinyl acetate copolymer resin, polyester-acrylic. Examples include copolymer resins, urethane resins, styrene resins, acrylic resins, phenol resins, silicone resins, epoxy resins, melamine resins, and polyolefin resins. In addition, fluorine materials such as polyvinylidene fluoride (PVDF) and vinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), silicone rubber, and the like are also included. These high molecular polymers may be used alone or in combination of two or more. Of these, adhesive resin such as epoxy resin, acrylic resin, urethane resin, silicone resin, etc. can be used to further improve the adhesion to the conductive porous substrate or separator and the adhesion to adjacent members. Is possible.

Examples of the ion conductive polymer resin include a fluorine-based ion conductive polymer, specifically, a perfluorocarbon sulfonic acid (PFS) polymer. Specific examples of such ion conductive polymer resins include “Nafion” (registered trademark) manufactured by DuPont, “Flemion” (registered trademark) manufactured by Asahi Glass Co., Ltd., and the like. The concentration of the ion conductive polymer resin contained in the ion conductive polymer resin-containing solution when purchasing a commercially available product is usually about 5% by mass to 60% by mass, preferably about 20% by mass to 40% by mass. .

Further, if an elastomer such as fluoro rubber is used as the polymer, the flexibility of the first conductive porous layer 11 can be further improved. In addition, as the polymer, a suspension in which polymer polymer particles are dispersed may be used, or a polymer polymer dissolved in a dispersion medium may be used. When using a suspension in which polymer polymer particles are dispersed, it is preferable to prepare by dispersing the polymer in a dispersion medium or use a commercially available product. As the dispersion medium, for example, known or commercially available alcohols, ketones, aromatic hydrocarbons, esters, and other organic solvents can be used in addition to water, for example, having about 1 to 5 carbon atoms. Monohydric or polyhydric alcohols, ketones having a total carbon number of about 3 to 6, aromatic hydrocarbons having a carbon number of about 6 to 10, esters having a total carbon number of about 3 to 6, N-methyl Examples include pyrrolidone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide and the like. Specifically, water, methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol, 1-pentanol; ethylene glycol; methyl ethyl ketone, methyl isobutyl ketone; toluene; ethyl acetate; N-methylpyrrolidone, dimethyl sulfoxide, dimethyl Examples include formamide and dimethylacetamide.

In addition, in order to impart water repellency to the first conductive porous layer 11, it is possible to use a water repellant resin such as a fluororesin as long as the amount does not impair the effects of the present invention. In the present invention, since the modified polyolefin resin having excellent water repellency is used, the first conductive porous layer 11 is not necessarily required to contain the water repellency resin. However, it is effective for improving the water repellency. is there. Examples of such a fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyvinylidene fluoride (PVDF), and vinylidene fluoride-hexafluoropropylene copolymer ( PVDF-HFP), perfluoroalkoxy resin (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, PFA), ethylene-tetrafluoroethylene copolymer (ETFE), and the like.

High molecular polymers other than these modified polyolefin resins may be used alone or in combination of two or more. Among these, it is preferable to use a water repellent resin from the viewpoint of water repellency, acid resistance, alkali resistance, heat resistance, etc. (particularly water repellency).

Content In the first conductive porous layer 11, the blending ratio of each of the above components is preferably 5 to 200 parts by mass, for example, 40 parts by mass to 100 parts by mass of the conductive carbon particles. About 100 parts by mass is more preferable. When the first conductive porous layer 11 contains a polymer other than the modified polyolefin resin, the content is other than the modified polyolefin resin with respect to 100 parts by mass of the conductive carbon particles. The polymer is preferably about 5 to 200 parts by weight (particularly about 40 to 100 parts by weight).

Since the modified polyolefin resin is contained in the first conductive porous layer 11 as described above, the battery gas diffusion layer of the present invention has good dispersibility and the uniform first conductive porous layer 11. In addition to obtaining good performance as the conductive porous layer, it is possible to improve the adhesion to the conductive porous substrate or the separator.

As described above, the battery gas diffusion layer of the present invention is excellent in adhesion to the conductive porous substrate or the separator. Therefore, even under weak conditions (low temperature and low pressure conditions), the conductive porous substrate or It can be fully integrated with the separator. For this reason, it can suppress that the space | gap of the gas diffusion layer 1 for batteries is crushed. Further, the surface of the battery gas diffusion layer 1 opposite to the side in contact with the conductive porous substrate or the separator is deformed by the influence of the roughness of the surface of the conductive porous substrate or the flow path of the separator. Can also be suppressed. Thus, since it can suppress that the gas diffusion layer 1 for batteries deform | transforms, adhesiveness with a catalyst layer becomes favorable and it is also possible to make battery performance favorable.

Furthermore, since the battery gas diffusion layer of the present invention includes the first conductive porous layer 11 containing the modified polyolefin resin, the first conductive porous layer 11 is easily peeled from the base material. For this reason, when it peels from a base material after forming the 1st electroconductive porous layer 11 on a base material, the 1st electroconductive porous layer 11 remains on a base material, a film | membrane cracks, or a crack generate | occur | produces Can be suppressed.

(1-2) Second conductive porous layer 12
In the gas diffusion layer for a battery of the present invention, as shown in FIG. 2, in addition to the first conductive porous layer 11 described above, a second conductive porous containing a conductive carbon material and a polymer is included. The layer 12 may be provided. That is, in the battery gas diffusion layer 1 of the present invention, the second conductive porous layer 12 may be provided on the first conductive porous layer 11. By adopting such a configuration, the battery gas diffusion layer 1 of the present invention has various functions while improving the adhesion between the battery gas diffusion layer 1 of the present invention and the conductive porous substrate or separator. (Water repellency, adhesion with a catalyst layer described later, high diffusibility, water retention, etc.) can also be imparted. The second conductive porous layer 12 is formed on the first conductive porous layer 11 by using, for example, a second conductive porous layer forming composition containing a conductive carbon material and a polymer. can do. The thickness of the second conductive porous layer 12 is usually about 1 μm to 300 μm, and particularly preferably about 5 μm to 250 μm. When the thickness of the second conductive porous layer 12 is less than 1 μm, the conductive porous substrate is used in combination with a conductive porous substrate having a function of supporting the conductive porous layer, which will be described later. The catalyst layer and the electrolyte membrane may be damaged due to the influence of the uneven shape due to the surface roughness. Moreover, when thickness exceeds 300 micrometers, while gas diffusibility falls, resistance becomes large and can cause a battery performance fall. From the viewpoint of space saving, the thickness of the second conductive porous layer 12 is preferably 250 μm or less.

Conductive carbon material The conductive carbon material is not particularly limited, and examples thereof include conductive carbon particles and conductive carbon fibers. As the conductive carbon particles and the conductive carbon fibers, the same materials as those exemplified in the first conductive porous layer 11 can be used.

As the polymer, the same material as the polymer other than the modified polyolefin resin used for the first conductive porous layer 11 can be used. That is, as the polymer, ion conductive polymer resin (Nafion, etc.), polyvinyl alcohol resin, polyvinyl acetate resin, styrene-acrylic copolymer resin, styrene-vinyl acetate copolymer resin, ethylene-vinyl acetate. Examples include copolymer resins, polyester-acrylic copolymer resins, urethane resins, styrene resins, acrylic resins, phenol resins, silicone resins, epoxy resins, melamine resins, and polyolefin resins. In addition, fluorine materials such as polyvinylidene fluoride (PVDF) and vinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), silicone rubber, and the like are also included. These high molecular polymers may be used alone or in combination of two or more. Of these, an adhesive resin such as an epoxy resin, an acrylic resin, a urethane resin, a silicone resin, or a polyolefin resin can be used to improve the adhesion to the catalyst layer.

Examples of the ion conductive polymer resin include a fluorine-based ion conductive polymer, specifically, a perfluorocarbon sulfonic acid (PFS) polymer. By having a fluorine atom with high electronegativity, it is chemically very stable, the dissociation degree of a sulfonic acid group is high, and high ionic conductivity can be realized. Specific examples of such ion conductive polymer resins include “Nafion” (registered trademark) manufactured by DuPont, “Flemion” (registered trademark) manufactured by Asahi Glass Co., Ltd., and the like. The concentration of the ion conductive polymer resin contained in the ion conductive polymer resin-containing solution when purchasing a commercially available product is usually about 5% by mass to 60% by mass, preferably about 20% by mass to 40% by mass. .

Further, if an elastomer such as fluoro rubber is used as the polymer, the flexibility of the second conductive porous layer 12 can be further improved. In addition, as the polymer, a suspension in which polymer polymer particles are dispersed may be used, or a polymer polymer dissolved in a dispersion medium may be used. When using a suspension in which polymer polymer particles are dispersed, it is preferable to prepare by dispersing the polymer in a dispersion medium or use a commercially available product. As the dispersion medium, for example, known or commercially available alcohols, ketones, aromatic hydrocarbons, esters, and other organic solvents can be used in addition to water, for example, having about 1 to 5 carbon atoms. Monohydric or polyhydric alcohols, ketones having a total carbon number of about 3 to 6, aromatic hydrocarbons having a carbon number of about 6 to 10, esters having a total carbon number of about 3 to 6, N-methyl Examples include pyrrolidone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide and the like. Specifically, water, methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol, 1-pentanol; ethylene glycol; methyl ethyl ketone, methyl isobutyl ketone; toluene; ethyl acetate; N-methylpyrrolidone, dimethyl sulfoxide, dimethyl Examples include formamide and dimethylacetamide.

Further, in order to impart water repellency to the second conductive porous layer 12, it is also possible to use a water repellant resin such as a fluororesin as long as the amount does not impair the effects of the present invention. This is particularly effective when a material having poor water repellency is used as the polymer. Examples of such a fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyvinylidene fluoride (PVDF), and vinylidene fluoride-hexafluoropropylene copolymer ( PVDF-HFP), perfluoroalkoxy resin (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, PFA), ethylene-tetrafluoroethylene copolymer (ETFE), and the like.

These polymer polymers may be used alone or in combination of two or more. Among these, it is preferable to use a water repellent resin from the viewpoint of water repellency, acid resistance, alkali resistance, heat resistance, etc. (particularly water repellency).

Content In the second conductive porous layer 12, the blending ratio of each of the above components is preferably 5 parts by mass to 200 parts by mass, for example, 40 parts by mass with respect to 100 parts by mass of the conductive carbon particles. About 100 parts by mass is more preferable.

(1-3) Configuration of Battery Gas Diffusion Layer 1 of the Present Invention The first conductive porous layer 11 described above may have only one layer in the battery gas diffusion layer 1 of the present invention. You may have two or more layers. Further, when the battery gas diffusion layer 1 of the present invention includes the second conductive porous layer 12 described above, the battery gas diffusion layer 1 of the present invention may have only one layer, You may have two or more layers. In the battery gas diffusion layer 1 of the present invention, when the outermost layer in contact with the conductive porous substrate or the separator is the first conductive porous layer 11, It is possible to more strongly integrate the battery gas diffusion layer 1 of the present invention with the conductive porous substrate or separator while further suppressing the collapse of the voids. Further, in the battery gas diffusion layer 1 of the present invention, when the outermost layer on the side opposite to the side in contact with the conductive porous substrate or the separator is the first conductive porous layer 11, the gas diffusion for battery of the present invention. The adhesion between the layer 1 and the catalyst layer can be made better. From these viewpoints, the battery gas diffusion layer 1 of the present invention is composed of the first conductive porous layer 11 alone or a plurality of conductive porous layers, and both outermost layers are the first conductive porous layers. The aspect which is 11 is preferable.

From this point of view, the configuration of the gas diffusion layer 1 of the present invention is that the first conductive porous layer 11 is the first and the second conductive porous layer 12 is the second. Layer; first and second gas diffusion layer; first, first, and first gas diffusion layer; first, second, and first gas diffusion layer; sequentially first, second, and second Examples include a second gas diffusion layer, and the battery gas diffusion layer 1 of the present invention is provided with various functions such as adhesion to a catalyst layer described later, water repellency, high diffusibility, and water retention. From the viewpoint, the first gas diffusion layer, the first and second gas diffusion layers, the first, second and first gas diffusion layers in this order are preferable.

(1-4) Conductive porous substrate 13
The first conductive porous layer 11 and the second conductive porous layer 12 described above are used integrally with other layers having a function of supporting the conductive porous layer, as shown in FIGS. This facilitates handling and improves workability.

As another layer having a function of supporting such a conductive porous layer, for example, a conductive porous substrate 13 can be used (FIGS. 3 to 4). Specifically, in the battery gas diffusion layer 1 of the present invention described above, the outermost first conductive porous layer 11 and the conductive porous base material 13 are integrated, and the entire battery gas diffusion layer is formed. It can be used as layer 1. By adopting such a configuration, the first conductive porous layer 11 and the conductive porous substrate 13 are integrated while suppressing the collapse of the voids of the battery gas diffusion layer 1 of the present invention. be able to. At this time, the surface of the battery gas diffusion layer 1 opposite to the side in contact with the conductive porous substrate 13 is prevented from being deformed by the influence of the roughness of the surface of the conductive porous substrate 13. You can also. Thus, since it can suppress that the gas diffusion layer 1 for batteries deform | transforms, adhesiveness with a catalyst layer becomes favorable and it is also possible to make battery performance favorable.

The conductive porous substrate 13 is not particularly limited as long as it has conductivity and is porous, and a known or commercially available material can be used. Examples thereof include carbon paper, carbon cloth, carbon felt and the like.

The thickness of the conductive porous substrate 13 is usually about 50 μm to 1000 μm, preferably about 100 μm to 400 μm.

The conductive porous substrate 13 may be a porous metal body made of a metal mesh, a metal foam or the like in order to diffuse the oxidant gas to the catalyst layer described later. By using the porous metal body, the conductivity is further improved. As the metal used for the porous metal body, nickel, palladium, silver, stainless steel, or the like can be used. Moreover, in order to improve corrosion resistance and electrical conductivity, the metal mesh and the metal foam surface may be plated. The material of the plating is not particularly limited, and examples thereof include metals such as platinum, ruthenium, rhodium, tungsten, tantalum, and gold or alloys thereof; carbon; composites of corrosion-resistant resins such as epoxy resins and acrylic resins and carbon, and the like. . Among these, gold is preferable from the viewpoint of high water repellency.

The conductive porous substrate 13 is preferably a substrate that has been subjected to a water repellent treatment in advance. Thereby, the water repellency of the conductive porous substrate 13 can be further improved.

Examples of the water repellent treatment include a method of immersing the conductive porous substrate 13 in an aqueous dispersion in which a fluororesin or the like is dispersed. Examples of the fluororesin include the above-described resins. In this case, in order to disperse the fluororesin in water, it is preferable to use a dispersant described later and use it as an aqueous suspension containing the fluororesin and the aqueous dispersant.

The content of the fluororesin in the aqueous dispersion is, for example, preferably about 1 to 30 parts by mass, preferably about 2 to 20 parts by mass with respect to 100 parts by mass of water.

In the battery gas diffusion layer 1 of the present invention, even when the conductive porous substrate 13 is used as another layer having a function of supporting the conductive porous layer, It can suppress that a space | gap is crushed. For example, the collapse rate of the voids is preferably 33.3% or less, and more preferably 25.0% or less. The smaller the void collapse rate, the better. However, the lower limit is usually about 0.3%. The crushing ratio of the voids is determined by integrating the conductive porous substrate 13 by peeling the conductive porous substrate 13 from the battery gas diffusion layer 1 of the present invention and measuring the thickness of the battery gas diffusion layer 1. Compared with the film thickness of the previous battery gas diffusion layer 1,
Crushing rate (%) = 100− (film thickness after integration) / (film thickness before integration) × 100
Calculate as

In the present invention, the thickness of the entire conductive porous layer is preferably 1 μm to 300 μm, more preferably 50 μm to 250 μm when integrated with the conductive porous substrate 13. That is, when only the first conductive porous layer 11 is formed, the thickness of the first conductive porous layer 11 is preferably within the above range, and the first conductive porous layer 11 and the second conductive layer 11 When both the porous layer 12 and the porous layer 12 are formed, the total thickness is preferably within the above range.

2. Battery member 2
The first conductive porous layer 11 and the second conductive porous layer 12 described above are easy to handle and workability by being integrated with another layer having a function of supporting the conductive porous layer. improves.

As another layer having a function of supporting such a conductive porous layer, for example, a separator 21 can be used (FIGS. 5 to 6). Specifically, in the battery gas diffusion layer 1 of the present invention described above, the outermost first conductive porous layer 11 and the separator 21 can be integrated, and the whole can be used as the battery member 2. . By adopting such a configuration, the battery gas diffusion layer 1 of the present invention and the separator 21 can be integrated while suppressing the collapse of the voids of the battery gas diffusion layer of the present invention. At this time, the problem that the battery gas diffusion layer 1 is deformed by the influence of the flow path of the separator 21 and the surface opposite to the side in contact with the separator 21 is deformed can also be suppressed. Thus, since it can suppress that the gas diffusion layer 1 for batteries deform | transforms, adhesiveness with a catalyst layer becomes favorable and it is also possible to make battery performance favorable. However, in the battery gas diffusion layer 1 of the present invention, when the first conductive porous layer 11 and the conductive porous substrate 13 are integrated (when the conductive porous substrate 13 is the outermost layer). ), The separator 21 may be formed on the conductive porous substrate 13.

As the separator 21, any known or commercially available separator can be used.

The material of the separator 21 is not particularly limited and can be appropriately selected depending on the purpose. For example, metals such as stainless steel, copper, titanium, aluminum, rhodium, tantalum, and tungsten, or an alloy containing at least one of them; graphite; a carbon compound in which carbon is kneaded into a resin, and the like. Among these, from the viewpoints of strength, thinning of a battery (fuel cell, metal-air battery, etc.) and conductivity, the metal or an alloy containing at least one of these is preferable, and titanium and stainless steel are more preferable.

Also, the surface of the separator 21 may be plated in order to improve corrosion resistance and conductivity. Examples of the plating material include metals such as platinum, ruthenium, rhodium, tungsten, tantalum, and gold or alloys thereof; carbon; a composite of corrosion resistant resin such as epoxy resin and acrylic resin and carbon, and the like. Among these, gold is preferable from the viewpoint of high corrosion resistance, and in terms of cost, carbon or a composite of carbon and the above metal or an alloy thereof is preferable.

The separator 21 may be a separator with a flow path in which a gas flow path (rib) is formed, or may be a separator without a flow path in which a gas flow path is not formed in itself. . Moreover, the separator which made the porous body which plays the role of a gas flow path adjoined may be sufficient. Moreover, the separator which has a porous body area | region in itself may be sufficient. In the case of a separator without a flow channel in which the gas channel is not formed in the separator 21 itself, a combination with a porous body serving as a gas flow channel or a separator having a porous region in itself is preferable. Further, the gas flow path is not formed in the separator 21 itself, and the separator 21 itself has a porous region and may be combined with the porous material.

In a separator with a flow path in which a gas flow path (rib) is formed, the gas flow path flows hydrogen, air, etc., which are fuel of the fuel cell, and discharges water generated by the reaction of the fuel cell to the outside of the cell If it is a thing, the width | variety, depth, shape, etc. of a flow path are not restrict | limited in particular, According to the objective, it selects suitably. Usually, the width is 0.05 mm to 2 mm (preferably 0.05 mm to 1.5 mm), and the depth is 0.05 mm to 2 mm (preferably 0.1 mm to 1 mm).

In the separator having a flow path in which a gas flow path (rib) is formed, the surface of the gas flow path may have irregularities or may be flat. The surface of the flow path preferably has irregularities.

From the viewpoint of drainage, it is preferable that a water repellent layer is formed on part or all of the separator 21. Examples of the water repellent layer include at least one of sulfur and its compounds.

For example, nickel, palladium, silver, stainless steel, etc. can be used as the material of the porous body in the separator in which the porous body serving as a gas flow path is adjacent. Moreover, in order to improve corrosion resistance and electroconductivity, you may perform a plating process to the said porous body surface. The material of the plating is not particularly limited, and examples thereof include metals such as platinum, ruthenium, rhodium, tungsten, tantalum, and gold or alloys thereof; carbon; composites of corrosion-resistant resins such as epoxy resins and acrylic resins and carbon, and the like. . Among these, gold is preferable from the viewpoint of high corrosion resistance, and in terms of cost, carbon or a composite of carbon and the above metal or an alloy thereof is preferable.

The separator having a porous region is not particularly limited as long as the separator has a structure in which the porous region can serve as the gas flow path.

The separator 21 has a phosphorus-containing layer formed on at least one surface of the metal plate constituting the separator, preferably on both surfaces of the metal plate, more preferably on the entire surface of the metal plate. The phosphorus-containing layer can protect the surface of the metal plate from corrosion by the superacid (superacid) of the solid polymer electrolyte.

The substance constituting the phosphorus-containing layer varies depending on the type of metal plate, the type of phosphorus compound used in forming the phosphorus-containing layer, and the like.

As the phosphorus compound used for forming the phosphorus-containing layer, known inorganic phosphorus compounds can be widely used, and examples thereof include condensed phosphoric acid such as phosphoric acid and polyphosphoric acid, and salts thereof. Examples of the salt include alkali metal salts such as sodium salt and potassium salt, metal salts, and ammonium salts.

In the present invention, the phosphorus-containing layer may further contain a resin, a metal compound, or the like.

As the resin, known resins can be widely used, and examples thereof include acrylic resin, phenol resin, and urethane resin.

In the present invention, these resins can be used singly or in combination of two or more.

As the metal compound, known compounds can be widely used as long as they can be bonded to the resin when the phosphorus-containing layer is formed. Examples of such metal compounds include transition elements such as zirconium, titanium, molybdenum, tungsten, vanadium, manganese, cobalt, and cerium, salts of inner transition elements, oxo acids or salts thereof, complex fluoride acids or salts thereof, and the like. Can be mentioned.

These metal compounds are used singly or in combination of two or more.

Considering cost and bond strength (crosslinking strength) with the above resin, a zirconium compound is preferable. Examples of the zirconium compound include zirconium fluoride (zirconium hydrofluoric acid), zirconium fluoride ammonium, zirconium acetate, zirconium carbonate ammonium, zirconium nitrate and the like.

When the phosphorus-containing layer further contains a resin, a metal compound, etc., the thickness of the phosphorus-containing layer is usually about 100 nm to 500 nm.

The content of the resin and the metal compound in the phosphorus-containing layer is appropriately selected in consideration of corrosion resistance and the like.

When the separator 21 is used as another layer having a function of supporting the battery gas diffusion layer 1 of the present invention, the separator is more likely to collapse the voids of the conductive porous layer than a separator having a large flow path. From the viewpoint of suppressing and improving adhesion, a separator having a narrow channel width and a separator having no porous channel and a porous region are preferable.

In the battery member 2 of the present invention, even when the separator 21 is used as another layer having a function of supporting the conductive porous layer, it is possible to prevent the void of the battery member 2 of the present invention from being crushed. it can. For example, the collapse rate of the voids is preferably 33.3% or less, and more preferably 25.0% or less. The smaller the void collapse rate, the better. However, the lower limit is usually about 0.3%. The crushing rate of the gap is determined by measuring the film thickness of the battery gas diffusion layer 1 by peeling the separator 21 from the battery member 2 of the present invention. Compare and
Crushing rate (%) = 100− (film thickness after integration) / (film thickness before integration) × 100
Calculate as

In the present invention, the thickness of the entire conductive porous layer is preferably 10 μm to 300 μm, more preferably 20 μm to 250 μm, when integrated with the separator 21. That is, when only the first conductive porous layer 11 is formed, the thickness of the first conductive porous layer 11 is preferably within the above range, and the first conductive porous layer 11 and the second conductive layer 11 When both the porous layer 12 and the porous layer 12 are formed, the total thickness is preferably within the above range.

3. Method for Manufacturing Battery Gas Diffusion Layer and Battery Member (3-1) Method for Manufacturing Battery Gas Diffusion Layer 1 Provided with at least First Conductive Porous Layer 11 First Conductive Porous Layer 11 of the Present Invention The battery gas diffusion layer 1 comprising, for example,
(I) forming a first conductive porous layer 11 on a substrate using a conductive carbon material and a first conductive porous layer forming composition containing a modified polyolefin resin; and (II) It can be manufactured by a method comprising a step of peeling the substrate from the first conductive porous layer 11.

Process (I)
In step (I), the conductive carbon material and the modified polyolefin resin described above can be used.

In the present invention, the first conductive porous layer forming composition includes, in addition to the conductive carbon material and the modified polyolefin resin, a polymer other than the modified polyolefin resin as long as the effects of the present invention are not impaired. A polymer, a dispersant, a dispersion medium, a foaming agent, a curing agent, and the like can be included. In addition, although the high molecular polymer used by this invention may be melt | dissolving or disperse | distributing in a solvent, the dispersion medium used here is used separately from such a solvent. As for resins other than the modified polyolefin resin, those described above can be adopted.

The dispersant is not limited as long as it is a dispersant that can disperse the conductive carbon material and the modified polyolefin resin in a dispersion medium such as water, and a known or commercially available dispersant can be used. Examples of such a dispersant include nonionic dispersants such as polyoxyethylene distyrenated phenyl ether, polyoxyethylene alkyl ether, and polyethylene glycol alkyl ether; alkyltrimethylammonium salts, dialkyldimethylammonium chloride, and alkylpyridium chloride. And anionic dispersants such as polyoxyethylene fatty acid esters and acidic group-containing structurally modified polyacrylates. These dispersing agents can be used alone or in combination of two or more.

The dispersion medium is not particularly limited, and water or other known or commercially available alcohols, ketones, aromatic hydrocarbons, esters, and other organic solvents can be used. Monohydric or polyhydric alcohols having about 1 to 5 carbon atoms, ketones having about 3 to 6 carbon atoms, aromatic hydrocarbons having about 6 to 10 carbon atoms, 3 to 6 carbon atoms Degree esters, N-methylpyrrolidone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide and the like. Specifically, water, methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 1-pentanol; methyl ethyl ketone, methyl isobutyl ketone; toluene; vinyl acetate; N-methylpyrrolidone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide Etc.

The foaming agent foaming agent is not particularly limited, and a material capable of forming pores in the first conductive porous layer 11 can be used. For example, a heating foaming agent that decomposes and foams by heating can be suitably used.

As the heating foaming agent, a compound having a decomposition temperature of 80 ° C. or higher, particularly about 120 ° C. to 250 ° C. is preferable. The amount of gas generated by the blowing agent is not particularly limited, and is usually about 50 ml / g to 500 ml / g, preferably about 200 ml / g to 300 ml / g. The average particle size is not particularly limited, and is usually about 1 μm to 50 μm, preferably about 2 μm to 5 μm. As the heating foaming agent, known organic foaming agents and inorganic foaming agents having the above decomposition temperature can be widely used.

Examples of the organic foaming agent include N, N′-dinitrosopentamethylenetetramine (DPT), azodicarbonamide (ADCA), 4,4′-oxybisbenzenesulfonylhydrazide (OBSH), and hydrazodicarbonamide (HDCA). Etc. Among these, it is preferable to use azodicarbonamide (ADCA) having a low temperature foaming property, 4,4'-oxybisbenzenesulfonyl hydrazide (OBSH) or the like. When an organic foaming agent is used, a urea aid can be used in combination as a foaming aid in order to lower the foaming temperature of the foaming agent.

無機 Examples of inorganic foaming agents include sodium bicarbonate.

When the composition for forming a hardener first conductive porous layer contains a hardener, the mechanical strength, heat resistance, and durability of the first conductive porous layer can be further increased.

The curing agent is not particularly limited as long as it is a curing agent capable of curing the modified polyolefin resin. As a hardening | curing agent, a polyfunctional isocyanate compound, a carbodiimide compound, an epoxy compound, an oxazoline compound etc. are mentioned, for example.

The polyfunctional isocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups. Specific examples of the polyfunctional isocyanate compound include, for example, diisocyanates such as isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and derivatives thereof (biuret, isocyanurate). , Adducts), polyisocyanates obtained by modifying these diisocyanates and derivatives thereof with polyester polyols, polyether polyols, acrylic polyols, polycarbonate polyols, and mixtures thereof.

The carbodiimide compound is not particularly limited as long as it is a compound having at least one carbodiimide group (—N═C═N—). As the carbodiimide compound, for example, a polycarbodiimide compound having at least two carbodiimide groups is preferable. Specific examples of particularly preferred carbodiimide compounds include those represented by the general formula (1):

[Wherein n is an integer of 2 or more. ]
A polycarbodiimide compound having a repeating unit represented by the general formula (2):

[Wherein n is an integer of 2 or more. ]
A polycarbodiimide compound having a repeating unit represented by the general formula (3):

[Wherein n is an integer of 2 or more. ]
The polycarbodiimide compound represented by these is mentioned. In the general formulas (1) to (3), n is an integer of 2 or more, preferably an integer of 2 to 30, and more preferably an integer of 3 to 20.

The epoxy compound is not particularly limited as long as it is a compound having two or more epoxy groups. Examples of the epoxy compound include bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, and tripropylene glycol diglycidyl ether. Polypropylene glycol diglycidyl ether, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, polyglycerin polyglycidyl ether, epoxy resin obtained by glycidyl etherification of phenol novolac or cresol novolac, and the like.

The oxazoline compound is not particularly limited as long as it is a compound having an oxazoline skeleton. Specific examples of the oxazoline compound include Epocros series manufactured by Nippon Shokubai Co., Ltd.

From the viewpoint of increasing the mechanical strength of the first conductive porous layer, the curing agent may be composed of two or more kinds of compounds.

Content In the composition for forming a first conductive porous layer, the above-described components can be adopted as the blending ratio of each component. In addition, in the case where a dispersant, a dispersion medium, a foaming agent, and the like are included in the first conductive porous layer forming composition, the content thereof is based on 100 parts by mass of the conductive carbon particles. Dispersant 0 to 100 parts by weight (particularly about 5 to 50 parts by weight), dispersion medium 0 to 1100 parts by weight (particularly about 100 to 1000 parts by weight), foaming agent 0 to part by weight About 200 parts by mass (particularly about 20 to 100 parts by mass) is preferable. Further, when the curing agent is included in the first conductive porous layer forming composition, the content thereof is 0.1 parts by mass to 50 parts by mass with respect to 100 parts by mass of the modified polyolefin resin. Preferably, 0.1 to 30 parts by mass is more preferable. In the first conductive porous layer forming composition, the content of the curing agent is preferably 1 equivalent to 30 equivalents as a reactive group in the curing agent with respect to 1 equivalent of the carboxy group in the modified polyolefin resin. 1 to 20 equivalents are more preferred. Thereby, the heat resistance of the gas diffusion layer for batteries of the present invention, durability, etc. can be raised more.

The first conductive porous layer forming composition can be obtained, for example, by mixing and dispersing the conductive carbon particles, the modified polyolefin resin, and other components. As a dispersion method, for example, known ultrasonic dispersion, homogenizer, media dispersion, stirrer dispersion, or the like can be used.

A base material will not be specifically limited if it is a base material which can form the 1st electroconductive porous layer 11 using the composition for 1st electroconductive porous layer formation, It uses a well-known or commercially available base material widely. Can do. Examples of such a substrate include polyimide, polyethylene terephthalate, aramid, polyamide (nylon), polysulfone, polyethersulfone, polyphenylene sulfide, polyether etherketone, polyetherimide, polyarylate, polyethylene naphthalate, polypropylene. And the like. In addition, ethylene tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), etc. Can also be used. Among these, a polymer film excellent in heat resistance and easily available is preferable. For example, films of polyethylene terephthalate, polyethylene naphthalate, polytetrafluoroethylene (PTFE), polyimide, and the like are preferable.

It is preferable that a release layer is laminated on the substrate. Examples of the release layer include those composed of known waxes. Moreover, you may use the film etc. which were coated with SiOx, a fluororesin, etc. as a base material with which the release layer was laminated | stacked.

The thickness of the base material is preferably about 6 μm to 100 μm, particularly preferably about 10 μm to 60 μm, from the viewpoints of handleability and economy.

As a method for forming the first conductive porous layer 11 on the substrate using the first conductive porous layer forming composition, for example, a coating method, a spray method, a dipping method, or the like can be adopted. From the viewpoint of obtaining a more uniform first conductive porous layer 11 and better performance as the conductive porous layer, the coating method is preferred in the present invention. Specifically, the first conductive porous layer is formed by coating and drying the composition for forming the first conductive porous layer on the substrate, and further through a foaming step when a foaming agent is contained. 11 is preferably formed.

As a method for applying the first conductive porous layer forming composition, it is applied using a blade such as a known or commercially available doctor blade, a device such as a wire bar or a squeegee, an applicator, die coating, screen printing, comma coating, or the like. It is preferable.

When the coating method is employed, the coating amount of the first conductive porous layer forming composition is, for example, such as gas permeation performance, smoothness, water discharging property and retention property to the first conductive porous layer 11. In order to impart water management characteristics, the first conductive porous layer 11 after drying is preferably applied so that the thickness thereof is about 1 μm to 150 μm, preferably about 5 μm to 100 μm. When it is desired to give gas diffusion performance effect to the first conductive porous layer 11, the thickness of the first conductive porous layer 11 after drying is about 1 μm to 300 μm, preferably about 20 μm to 250 μm. It is good to apply to. In addition, from the viewpoint of space saving, it is preferable to adjust the thickness of the first conductive porous layer 11 to be 250 μm or less. In addition, it absorbs more pressure from other members (conductive porous substrate, separator, etc.), and when the processing accuracy of the separator is poor and there are variations in shape, thickness, etc., the entire cell can be absorbed From the viewpoint of improving the accuracy, it is preferable to increase the thickness of the conductive porous layer (about 20 μm to 300 μm).

Further, when the coating method is adopted, it is preferable that the drying temperature is appropriately changed depending on conditions such as the volatilization temperature of the solvent (dispersion medium or the like) used.

After drying to obtain the first conductive porous layer 11, drying treatment may be performed at a higher temperature (for example, about 150 ° C. to 500 ° C.) as necessary.

Furthermore, the surface of the first conductive porous layer 11 may be subjected to a surface treatment in order to improve adhesion with other members, impart water repellency, or the like. Examples of the surface treatment include mechanical treatment that physically forms surface irregularities with a metal brush, sandblast, etc., mat treatment, corona discharge treatment, plasma discharge treatment, ultraviolet treatment, flame treatment, and the like.

Process (II)
After forming the first conductive porous layer 11 on the base material by the step (I), the base material is peeled from the first conductive porous layer 11. The peeling method is not particularly limited, and a method used in a conventional method may be adopted.

In addition, when forming multiple layers of the 1st electroconductive porous layer 11, what is necessary is just to perform said process (I) in multiple times so that a desired structure may be obtained. The first conductive porous layer 11 is formed on the one conductive porous layer 11). At this time, the order of the steps is not particularly limited as long as the steps (I) are performed after the first step, after the first step (I).

(3-2) Method for Producing Battery Gas Diffusion Layer 1 Comprising at least First Conductive Porous Layer 11 and Second Conductive Porous Layer 12 The battery gas diffusion layer 1 of the present invention is a second conductive porous layer. When the porous layer 12 is provided (for example, when the second conductive porous layer 12 is formed on the first conductive porous layer 11), the process (I) described in (3-1) above is performed. ) And (II),
(III) A second conductive porous layer 12 is formed on the first conductive porous layer 11 by using a second conductive porous layer forming composition containing a conductive carbon material and a polymer. It can manufacture by the manufacturing method also provided with the process to form.

Process (III)
In the step (III), the conductive carbon material and the high molecular polymer can employ the above-described ones.

In the present invention, the second conductive porous layer forming composition includes, in addition to the conductive carbon material and the polymer, the dispersant, the dispersion medium, A foaming agent or the like can be included. As the dispersant, the dispersion medium, and the foaming agent, those similar to the first conductive porous layer forming composition can be employed.

Content In the composition for forming the second conductive porous layer, the above-described components can be adopted as the blending ratio of each component. In addition, when the dispersant, the dispersion medium, the foaming agent, and the like are included in the second conductive porous layer forming composition, the content thereof is based on 100 parts by mass of the conductive carbon particles. Dispersant 0 to 100 parts by weight (particularly about 5 to 50 parts by weight), dispersion medium 0 to 1100 parts by weight (particularly about 10 to 1000 parts by weight), foaming agent 0 to part by weight About 200 parts by mass (particularly about 20 to 100 parts by mass) is preferable.

The second conductive porous layer forming composition can be obtained, for example, by mixing and dispersing the conductive carbon particles, the polymer, and other components. The dispersion method is not particularly limited, and for example, known ultrasonic dispersion, homogenizer, media dispersion, stirrer dispersion, and the like can be used.

Examples of the method for forming the second conductive porous layer 12 on the first conductive porous layer 11 using the second conductive porous layer forming composition include a coating method, a spray method, and an immersion method. In the present invention, a coating method is preferable. Specifically, the composition for forming the second conductive porous layer on the first conductive porous layer 11 is coated and dried, and when a foaming agent is contained, a foaming step is further performed, Two conductive porous layers 12 are preferably formed.

As a method for applying the second conductive porous layer forming composition, it is applied using a blade such as a known or commercially available doctor blade, a device such as a wire bar or a squeegee, an applicator, die coating, screen printing, comma coating, or the like. It is preferable.

When the coating method is adopted, the coating amount of the second conductive porous layer forming composition is, for example, such as gas permeation performance, smoothness, water discharging property and retaining property to the second conductive porous layer 12. In order to impart water management characteristics, the second conductive porous layer 12 after drying is preferably applied so that the thickness thereof is about 1 μm to 150 μm, preferably about 5 μm to 100 μm. When it is desired to give the gas diffusion performance effect to the second conductive porous layer 12, the thickness of the second conductive porous layer 12 after drying is about 1 μm to 300 μm, preferably about 20 μm to 250 μm. It is good to apply to. In addition, from the viewpoint of space saving, it is preferable to adjust the thickness of the first conductive porous layer 11 to be 250 μm or less. In addition, it absorbs more pressure from other members (conductive porous substrate, separator, etc.), and when the processing accuracy of the separator is poor and there are variations in shape, thickness, etc., the entire cell can be absorbed From the viewpoint of improving the accuracy, it is preferable to increase the thickness of the conductive porous layer (about 20 μm to 300 μm).

In addition, when the coating method is adopted, it is preferable that the drying temperature is appropriately changed depending on conditions such as a volatilization temperature of a solvent to be used (dispersion medium or the like).

After drying to obtain the second conductive porous layer 12, a drying treatment may be performed at a higher temperature (for example, about 150 ° C. to 500 ° C.) as necessary.

Furthermore, the surface of the second conductive porous layer 12 may be subjected to a surface treatment for improving adhesion with other members, imparting water repellency, and the like. Examples of the surface treatment include mechanical treatment that physically forms surface irregularities with a metal brush, sandblast, etc., mat treatment, corona discharge treatment, plasma discharge treatment, ultraviolet treatment, flame treatment, and the like.

In this embodiment, any of the order of step (I), step (II) and step (III); and the order of step (I), step (III) and step (II) can be adopted. From the viewpoint of the handleability of the layer, step (I), step (III),
The order of step (II) is preferred.

In addition, when forming multiple layers of the 1st electroconductive porous layer 11, what is necessary is just to perform said process (I) in multiple times so that a desired structure may be obtained. The first conductive porous layer 11 is formed on the first conductive porous layer 11 or the second conductive porous layer 12). Further, when a plurality of layers of the second conductive porous layer 12 are formed, the above-described step (III) may be performed a plurality of times so that a desired configuration is obtained (from the second time on, the already formed first The second conductive porous layer 12 is formed on the first conductive porous layer 11 or the second conductive porous layer 12). At this time, the order of the steps is not particularly limited as long as the steps (I) are performed after the first step, after the first step (I).

(3-3) Method for Producing Battery Gas Diffusion Layer 1 Comprising at least First Conductive Porous Layer 11 and Conductive Porous Base Material 13 The battery gas diffusion layer 1 of the present invention is a conductive porous substrate. 13 (for example, the case where the first conductive porous layer 11 and the conductive porous base material 13 are provided), the battery gas diffusion layer 1 of the present invention is the above (3-1). In addition to the steps (I) and (II) described,
(IV) The conductive porous substrate 13 can be manufactured by a manufacturing method including a step of laminating the conductive porous substrate 13 so as to be in contact with the first conductive porous layer 11.

Further, when the battery gas diffusion layer 1 of the present invention includes the conductive porous substrate 13 (for example, the first conductive porous layer 11, the second conductive porous layer 12, and the conductive porous group). In the case where the material 13 is provided), the battery gas diffusion layer 1 of the present invention includes the step (IV) in addition to the steps (I), (II) and (III) described in the above (3-2). It can manufacture with the manufacturing method provided.

Process (IV)
In the step (IV), the conductive porous substrate 13 may be the above-described one.

In step (IV), the conductive porous substrate 13 is laminated so as to be in contact with the first conductive porous layer 11. At this time, the conductive porous substrate 13, the first conductive porous layer 11, It is preferable to laminate so as to be integrated.

Specifically, it is preferable that the conductive porous substrate 13 and the first conductive porous layer 11 are arranged so as to be in contact with each other and then integrated by applying pressure. Further, during the pressurizing operation, it is preferable to heat press the heated pressure surface in order to further improve the adhesion under a lower pressure condition.

In the present invention, since the first conductive porous layer 11 contains the modified polyolefin resin, the hot press conditions are weak in order to further prevent the voids in the first conductive porous layer 11 from being crushed. Even under the conditions (low temperature and low pressure conditions), the conductive porous substrate 13 and the conductive porous substrate A11 can be sufficiently integrated. Moreover, it can also suppress that the surface on the opposite side to the side which contact | connects the conductive porous base material 13 of the battery gas diffusion layer 1 receives the influence of the roughness of the surface of the conductive porous base material 13, and deform | transforms. . On the other hand, when the hot pressing condition is a strong condition (high temperature and high pressure condition), the gap of the first conductive porous layer 11 is crushed and the side of the battery gas diffusion layer 1 in contact with the conductive porous substrate 13 The surface on the opposite side may be deformed under the influence of the roughness of the surface of the conductive porous substrate 13. In addition, the appearance of the catalyst layer side surface may be affected. From this point of view, the conditions for hot pressing are as follows: heating temperature is 40 ° C. to 150 ° C. (especially 60 ° C. to 120 ° C.), applied pressure is 0.5 MPa to 10 MPa (especially 1 MPa to 5 MPa), and hot pressing time is 10 seconds. It is preferable to set it to ~ 300 seconds (particularly 30 seconds to 200 seconds).

In this aspect, when manufacturing the battery gas diffusion layer 1 including the first conductive porous layer 11 and the conductive porous substrate 13, the order of the step (I), the step (II), and the step (IV). And any of the steps (I), (IV) and (II) can be employed, but from the viewpoint of adhesion (the adhesion can be improved because a smooth surface on the substrate surface side can be used); It is preferable to carry out in the order of (I), step (II) and step (IV). Moreover, in this aspect, when manufacturing the gas diffusion layer 1 for batteries provided with the 1st conductive porous layer 11, the 2nd conductive porous layer 12, and the conductive porous base material 13, process (I), Step (II), Step (III) and Step (IV) in order; Step (I), Step (II), Step (IV) and Step (III) in order; Step (I), Step (IV), Step Any of the order of (II) and step (III); and the order of step (I), step (III), step (II) and step (IV) can be adopted, but from the viewpoint of handling and adhesion, It is preferable to carry out in the order of I), step (III), step (II) and step (IV). In addition, when performing a process (I) and / or a process (III) in multiple times, especially if the order of each process is performed after the 1st process (I) when performing the process (I) after the 2nd time, it will restrict | limit. Not.

(3-4) Method for producing battery member 2 including at least first conductive porous layer 11 and separator 21 Battery member 2 of the present invention including first conductive porous layer 11 (for example, first conductive Battery member comprising the porous porous layer 11 and the separator 21), in addition to the steps (I) and (II) described in (3-1) above,
(V) The separator 21 can be manufactured by a manufacturing method including a step of laminating the separator 21 so as to be in contact with the first conductive porous layer 11.

Further, the battery member 2 of the present invention including the first conductive porous layer 11 and the second conductive porous layer 12 (for example, the first conductive porous layer 11 and the second conductive porous layer 12). And the battery member 2 including the separator 21 are manufactured by the manufacturing method including the step (V) in addition to the steps (I), (II), and (III) described in the above (3-2). be able to.

Process (V)
In the step (V), the separator 21 can employ the above-described one.

In the step (V), the separator 21 is laminated so as to be in contact with the first conductive porous layer 11. At this time, the separator 21 and the first conductive porous layer 11 may be laminated so as to be integrated. preferable.

Specifically, it is preferable that the separator 21 and the first conductive porous layer 11 be arranged so as to be in contact with each other and then integrated by performing a heat press. Under the present circumstances, it is preferable to arrange | position so that the separator 21 may contact | connect the 1st electroconductive porous layer 11 which was in contact with the base material in process (I) among the layers which comprise the gas diffusion layer 1 for batteries.

In the present invention, since the first conductive porous layer 11 contains a modified polyolefin resin, the hot press conditions are set in order to further prevent the voids in the first conductive porous layer 11 from being crushed. Even under weak conditions (low temperature and low pressure conditions), the separator 21 and the first conductive porous layer 11 can be sufficiently integrated. On the other hand, if the hot pressing condition is a strong condition (high temperature and high pressure condition), the voids of the first conductive porous layer 11 may be crushed. Further, the first conductive porous layer 11 may be deformed and affect the appearance of the catalyst layer side surface. From this point of view, the conditions for hot pressing are as follows: heating temperature is 40 ° C. to 150 ° C. (especially 60 ° C. to 120 ° C.), applied pressure is 0.5 MPa to 10 MPa (especially 1 MPa to 5 MPa), and hot pressing time is 10 seconds. It is preferable to set it to ~ 300 seconds (particularly 30 seconds to 200 seconds).

In this aspect, when manufacturing the battery member 2 including the first conductive porous layer 11 and the separator 21, the order of the step (I), the step (II) and the step (V); and the step (I), Any of the order of the step (V) and the step (II) can be adopted, but from the viewpoint of adhesion, it is preferable to carry out in the order of the step (I), the step (II) and the step (V). Moreover, in this aspect, when manufacturing the battery member 2 provided with the 1st electroconductive porous layer 11, the 2nd electroconductive porous layer 12, and the separator 21, process (I), process (II), process ( III) and step (V); step (I), step (II), step (V) and step (III) in order; step (I), step (V), step (II) and step (III) ); And step (I), step (III), step (II) and step (V) can be employed, but from the viewpoint of handling and adhesion, step (I) and step (III) It is preferable to carry out in the order of step (II) and step (V). In addition, when performing a process (I) and / or a process (III) in multiple times, especially if the order of each process is performed after the 1st process (I) when performing the process (I) after the 2nd time, it will restrict | limit. Not.

Further, when the battery gas diffusion layer 1 of the present invention includes the conductive porous substrate 13, the separator 21 may be laminated on the conductive porous substrate 13. Moreover, when manufacturing the battery member 2 provided with the 1st electroconductive porous layer 11, the electroconductive porous base material 13, and the separator 21, process (I), process (II), process (IV), and process ( V) order; step (I), step (IV), step (II) and step (V) order; and step (I), step (IV), step (V) and step (II) order However, from the viewpoint of adhesion, it is preferable to perform the steps (I), (II), (IV), and (V) in this order. In this embodiment, when producing a battery member comprising the first conductive porous layer 11, the second conductive porous layer 12, the conductive porous substrate 13, and the separator 21, the step (I), Step (II), Step (III), Step (IV) and Step (V) in order; Step (I), Step (II), Step (IV), Step (III) and Step (V) in order; Step (I), Step (II), Step (IV), Step (V) and Step (III) in this order; Step (I), Step (IV), Step (II), Step (III) and Step (V) In the order of step (I), step (IV), step (II), step (V) and step (III); step (I), step (IV), step (V), step (II) and Any of the order of step (III); and step (I), step (III), step (II), step (IV) and step (V) can be adopted, but from the viewpoint of handling and adhesion, (I), step (III), step It is preferable to carry out in the order of (II), step (IV) and step (V). In addition, when performing a process (I) and / or a process (III) in multiple times, especially if the order of each process is performed after the 1st process (I) when performing the process (I) after the 2nd time, it will restrict | limit. Not.

4). Battery membrane-electrode assembly 3 and battery 4
Using the gas diffusion layer 1 for a battery or the battery member 2 of the present invention as a gas diffusion layer for a fuel cell or a gas diffusion layer for a metal-air battery, as shown in FIGS. 3 or battery 4 (solid polymer fuel cell, metal-air battery, etc.) can be produced. Specifically, one side or both sides of a catalyst layer-electrolyte membrane laminate 31 composed of a laminate of the catalyst layer 312 and the electrolyte membrane 311 or a laminate in which the catalyst layer 312, the electrolyte membrane 311 and the catalyst layer 312 are formed in this order. Furthermore, it is preferable that the battery gas diffusion layer 1 or the battery member 2 of the present invention is laminated so that the first conductive porous layer 11 or the second conductive porous layer 12 and the catalyst layer are in contact with each other. A representative example of such a membrane-electrode assembly 3 for a battery according to the present invention is as shown in FIGS. 7 to 8. However, the configuration is not limited to this. For example, “catalyst layer-electrolyte membrane” Battery membrane-electrode assembly 3 in which the first conductive porous layer 11 is laminated on one side of the laminate 31, “Catalyst layer-electrolyte membrane laminate 31, the second conductive porous layer 12 on one side of the laminate 31. In addition, the first conductive porous layer 11 was laminated on both surfaces of the battery membrane-electrode assembly 3 in which the first conductive porous layer 11 was laminated in this order and the “catalyst layer-electrolyte membrane laminate 31”. Battery membrane-electrode assembly 3 "," catalyst layer-battery membrane in which the second conductive porous layer 12 and the first conductive porous layer 11 are laminated in this order on both surfaces of the electrolyte membrane laminate 31- Electrode assembly 3 ”,“ Catalyst layer-electrolyte membrane laminate 31 on one side, first conductive porous layer 11 and conductive porous layer ” Battery membrane-electrode assembly 3 in which materials 13 are laminated in this order ”and“ catalyst layer-electrolyte membrane laminate 31 ”on one side of second conductive porous layer 12, first conductive porous layer 11 and conductive layer 13. Battery porous membrane 13 in which the porous porous substrate 13 is laminated in this order ”and“ catalytic layer-electrolyte membrane laminated body 31 on both sides of the first conductive porous layer 11 and the conductive porous substrate. 13 are laminated in this order on the battery membrane-electrode assembly 3 ”and the“ catalyst layer-electrolyte membrane laminate 31 ”on both sides of the second conductive porous layer 12, the first conductive porous layer 11, and the conductive layer. Any battery membrane-electrode assembly 3 ”in which the porous porous substrate 13 is laminated in this order can be employed. In the case of producing a battery, the battery 4 of the present invention may be produced by laminating the obtained battery membrane-electrode assembly 3 with a separator 21 as necessary. At this time, the separator described above can be used as the separator 21. A typical example of such a battery 4 of the present invention is as shown in FIG. 9, but the configuration thereof is not limited to this. For example, “the first layer on the one side of the catalyst layer-electrolyte membrane laminate” A battery in which a conductive porous layer and a separator are laminated in this order ”,“ a second conductive porous layer, a first conductive porous layer, and a separator are laminated in this order on one side of a catalyst layer-electrolyte membrane laminate. Battery ”,“ battery in which the first conductive porous layer, the conductive porous substrate and the separator are laminated in this order on one side of the catalyst layer-electrolyte membrane laminate ”,“ catalyst layer-electrolyte membrane laminate A battery in which a second conductive porous layer, a first conductive porous layer, a conductive porous substrate and a separator are laminated in this order on one side ”,“ a first conductive on both sides of a catalyst layer-electrolyte membrane laminate ” A separator is placed on one side of the battery membrane-electrode assembly on which a porous porous layer is laminated. Layered battery ”,“ Catalyst layer-electrolyte membrane laminate on both sides of second conductive porous layer and first conductive porous layer in this order laminated on one side of membrane-electrode assembly for battery separator A battery in which a first conductive porous layer and a conductive porous substrate are laminated in this order on both sides of the catalyst layer-electrolyte membrane laminate, and a separator on one side of the membrane-electrode assembly. A battery in which a second conductive porous layer, a first conductive porous layer, and a conductive porous substrate are laminated in this order on both sides of the electrolyte membrane laminate. "Battery with separator laminated on one side of electrode assembly", "Battery with first conductive porous layer and separator laminated on both sides of catalyst layer-electrolyte membrane laminate", "Catalyst layer-electrolyte" A second conductive porous layer, a first conductive porous layer, and a separator are formed on both sides of the film laminate. A battery in which a first conductive porous layer, a conductive porous substrate and a separator are laminated in this order on both surfaces of a catalyst layer-electrolyte membrane laminate, and a catalyst. Any battery in which the second conductive porous layer, the first conductive porous layer, the conductive porous substrate, and the separator are stacked in this order on both surfaces of the layer-electrolyte membrane laminate can be employed.

In the present invention, once the produced gas diffusion layer 1 or battery member 2 of the present invention is laminated on one or both sides of a catalyst layer-electrolyte membrane laminate 31 described later, the membrane-electrode assembly 3 or The battery 4 can be produced. In this case, the battery gas diffusion layer 1 or the battery member 2 is preferably integrated with the catalyst layer-electrolyte membrane laminate 31. Also in this case, when the battery gas diffusion layer 1 or the battery member 2 is positioned downward, the battery gas diffusion layer 1 or the battery member 2 is not less than 5 minutes from the catalyst layer-electrolyte membrane laminate 31. It is preferable to adhere to such an extent that it does not peel off.

(4-1) Catalyst layer-electrolyte membrane laminate 31
Electrolyte membrane 311
The electrolyte membrane 311 may be a hydrogen ion conductive or hydroxide ion conductive electrolyte membrane, and a known or commercially available electrolyte membrane such as a hydrogen ion conductive electrolyte membrane or a hydroxide ion conductive electrolyte membrane may be used. . Specific examples of the hydrogen ion conductive electrolyte membrane include, for example, “Nafion” (registered trademark) membrane manufactured by DuPont, “Flemion” (registered trademark) membrane manufactured by Asahi Glass Co., Ltd., and “Aciplex” manufactured by Asahi Kasei Corporation. ”(Registered trademark) membrane,“ Gore Select ”(registered trademark) membrane manufactured by Gore, and the like. Specific examples of the hydroxide ion conductive electrolyte membrane include a hydrocarbon electrolyte membrane such as Aciplex (registered trademark) A-201, 211, 221 and the like manufactured by Asahi Kasei Co., Ltd., and Tokuyama Corp. Neoceptor (registered trademark) AM-1, AHA, and the like. As a fluororesin-based electrolyte membrane, Tosflex (registered trademark) IE-SF34 manufactured by Tosoh Corporation, and fumapem manufactured by FuMA-Tech ( (Registered trademark) FAA and the like.

The thickness of the electrolyte membrane 311 is usually about 20 μm to 250 μm, and particularly preferably about 20 μm to 150 μm.

Further, when the membrane-electrode assembly 3 for a battery according to the present invention is used for a metal-air battery, it is not limited to a solid electrolyte membrane, and a gel-like or liquid electrolyte can also be used. The material used for the electrolytic solution in this case is not particularly limited, and known or commercially available materials conventionally used for metal-air batteries can be used. For example, the electrolytic solution is selected corresponding to the metal of the negative electrode, but water, saline, an alkaline solution, a metal salt solution of the metal of the negative electrode, and the like are appropriately used.

Catalyst layer 312
The catalyst layer 312 only needs to contain a catalyst. For example, a catalyst layer in which catalyst particles are supported on carbon particles may be used. Further, the catalyst layer 312 may contain a polymer in addition to the catalyst.

Examples of the catalyst include platinum and platinum compounds. Examples of the platinum compound include an alloy of platinum and at least one metal selected from the group consisting of ruthenium, palladium, nickel, molybdenum, iridium, iron, cobalt, and the like. In general, the catalyst contained in the catalyst layer is platinum.

The carbon particles only need to have conductivity, and known or commercially available carbon particles can be widely used. For example, carbon black, graphite, activated carbon, or the like can be used alone or in combination. Examples of carbon black include channel black, furnace black, ketjen black, acetylene black, and lamp black. The arithmetic average particle diameter of the carbon particles is usually about 5 nm to 200 nm, preferably about 20 nm to 80 nm. The average particle diameter of the carbon particles is specified by 20 arithmetic average particle diameters based on an electron microscope observation image.

As the polymer, known materials can be used. Specifically, ion conductive polymer electrolyte, polyvinyl alcohol resin, polyvinyl acetate resin, styrene-acrylic copolymer resin, styrene-vinyl acetate copolymer resin, ethylene-vinyl acetate copolymer resin, polyester-acrylic Examples thereof include copolymer resins, urethane resins, styrene resins, acrylic resins, phenol resins, silicone resins, epoxy resins, melamine resins, polyolefin resins, and fluorine resins. In addition, fluorine-based materials such as polyvinylidene fluoride (PVDF) and vinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), silicone rubber, and the like are also included. These high molecular polymers may be used alone or in combination of two or more.

Examples of the ion conductive polymer electrolyte include perfluorosulfonic acid-based fluorine ion exchange resins, and more specifically, perfluorocarbon sulfonic acid polymer (PFS polymer). By introducing a fluorine atom having high electronegativity, it is chemically very stable, the dissociation degree of the sulfonic acid group is high, and high ion conductivity can be realized. Specific examples of such an ion conductive polymer electrolyte include “Nafion” (registered trademark) manufactured by DuPont, “Flemion” (registered trademark) manufactured by Asahi Glass Co., Ltd., and “Aciplex” manufactured by Asahi Kasei Corporation. (Registered trademark), “Gore Select” (registered trademark) manufactured by Gore, and the like. The concentration of the ion conductive polymer electrolyte contained in the ion conductive polymer electrolyte-containing solution is usually about 5% to 60% by mass, preferably about 20% to 40% by mass.

The thickness of the catalyst layer 312 is, for example, usually about 1 μm to 100 μm, preferably about 2 μm to 50 μm.

The catalyst layer 312 may be added with a non-polymer fluorine material such as fluorinated pitch, fluorinated carbon, and fluorinated graphite in addition to a fluororesin as a water repellent.

In the case of a metal-air battery, the catalyst used for the positive electrode includes manganese dioxide, gold, activated carbon, iridium oxide, perovskite complex oxide, metal-containing pigment, etc. in addition to the catalyst used in the anode catalyst or cathode catalyst. Can be used. The catalyst layer 312 can be formed by dispersing and applying these catalyst powders using the above water repellent as a binder. Alternatively, the catalyst layer 312 can be formed by vapor deposition of a material that can be vapor deposited. Alternatively, the catalyst layer 312 can be formed by reducing the metal salt solution on the electrode to precipitate the metal in a fine shape.

Also, the metal of the negative electrode is selected depending on what type of air battery is configured. Metals, alloys or metal compounds such as lithium (Li), sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), zinc (Zn), aluminum (Al), and iron (Fe) are negative electrodes. It can be used as an active material. In order to increase the contact area between the negative electrode and the electrolytic solution, the negative electrode preferably has fine pores.

Method for Producing Catalyst Layer-Electrolyte Membrane Laminate 31 The catalyst layer-electrolyte membrane laminate 31 is composed of, for example, a catalyst layer 312 and an electrolyte using a transfer film for forming a catalyst layer having a catalyst layer 312 formed on one side of a substrate. It can be manufactured by disposing a transfer film for forming a catalyst layer so as to face the film 311, applying pressure under heating conditions to transfer the catalyst layer 312 to the electrolyte film 311, and then peeling the transfer film. . If this operation is repeated twice, the catalyst layer-electrolyte membrane laminate 31 in which the catalyst layer 312 is laminated on both surfaces of the electrolyte membrane 311 can be manufactured. It is preferable to laminate the electrolyte membrane 311 on both surfaces simultaneously. One of the catalyst layers 312 formed at this time is an anode catalyst layer, and the other is a cathode catalyst layer. The anode catalyst layer and the cathode catalyst layer may be the same or different. When the gas diffusion layer 1 or battery member 2 of the present invention is laminated on one side of the catalyst layer-electrolyte membrane laminate 31, it may be laminated on the anode catalyst layer or on the cathode catalyst layer. Also good.

When transferring, it is preferable to apply pressure from the base film side of the transfer film for forming a catalyst layer using a known press machine or the like. The pressure level at that time is preferably about 0.5 MPa to 10 MPa, particularly preferably about 1 MPa to 8 MPa, in order to avoid poor transfer. Further, it is preferable to heat the pressure surface during this pressure operation in order to avoid transfer failure. The heating temperature is preferably changed as appropriate depending on the type of electrolyte membrane to be used.

The base film is not particularly limited, and the same base as the above base can be used. For example, polymer films such as polyimide, polyethylene terephthalate (PET), polysulfone, polyethersulfone, polyphenylene sulfide, polyether ether ketone, polyetherimide, polyarylate, polyethylene naphthalate (PEN), polyethylene, polypropylene, polyolefin, etc. Can be mentioned. In addition, ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE) It is also possible to use a heat-resistant fluororesin such as Among these, a polymer film that is inexpensive and easily available is preferable, and polyethylene terephthalate or the like is more preferable.

The thickness of the base film is usually about 6 μm to 150 μm, particularly about 12 μm to 75 μm, from the viewpoints of workability and economical efficiency for forming the catalyst layer 312 on the base film.

The base film may be a base film on which a release layer is laminated. Examples of the release layer include a layer composed of a known wax, a known SiOx, a plastic film coated with a fluororesin, and the like. Moreover, what was comprised by laminating | stacking a film with high mold release property on a base film, for example, what has structures, such as a laminated body of a PET base material and a heat resistant fluororesin base material, may be used.

Further, as a method of forming the catalyst layer 312 on the electrolyte membrane 311, in addition to the method of forming the catalyst layer 312 by the transfer described above, the catalyst layer forming composition is applied to the electrolyte membrane 311. It may be formed. Known conditions can be used for this.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. The present invention is not limited to the following examples.

<Material>
The following materials were used for the preparation of the first conductive porous layer forming composition and the second conductive porous layer forming composition.
Conductive carbon particles: average particle size 30 nm
Modified polyolefin resin: Aurorene 350S (manufactured by Nippon Paper Industries Co., Ltd .; modified polyolefin resin content of 10% by mass as solute)
Polymer: Solef 21216/1001 (manufactured by Solvay Solexis Corp .; PVDF; dissolved in methyl ethyl ketone so that the polymer content is 10% by mass).

Example 1
A composition for forming a first conductive porous layer is obtained by dispersing 100 parts by mass of conductive carbon particles, 500 parts by mass of a modified polyolefin resin (50 parts by mass of melt), and 1000 parts by mass of methylcyclohexane (MCH) by media dispersion. Was formulated. This composition for forming a first conductive porous layer was applied on a polyethylene terephthalate (PET) film on which a release layer was formed using an applicator so as to have a thickness of about 50 μm. Then, it was made to dry for about 15 minutes in the drying furnace set to 95 degreeC, and the 1st electroconductive porous layer (1) was produced on PET film. Then, the 1st electroconductive porous layer (1) was peeled from the PET film in which the release layer was formed, and the 1st electroconductive porous layer (1) (The gas diffusion layer for batteries of Example 1) was obtained. .

Next, the obtained first conductive porous layer (1) was formed in a metal mesh (SUS304 φ0.05 × 180 m / s; φ was wire diameter (mm), m / s was in 1 inch × 1 inch. The first conductive porous layer (1) and the metal mesh are subjected to hot pressing under the conditions of a pressing temperature of 60 ° C., a pressing pressure of 2 MPa, and a pressing time of 180 seconds. Produced a gas diffusion layer for battery (battery gas diffusion layer of Example 1 including a metal mesh). In this gas diffusion layer for a battery, when the first conductive porous layer (1) is positioned below the metal mesh, the first conductive porous layer (1) is 5 minutes after the metal mesh. Did not come off.

Example 2
In the same manner as in Example 1, a first conductive porous layer (1) was produced.

Next, the second conductive porous layer is formed by dispersing 100 parts by mass of conductive carbon particles, 500 parts by mass of the polymer (melting mass 50 parts by mass), and 1000 parts by mass of methyl ethyl ketone (MEK) by media dispersion. A composition for preparation was prepared. The composition for forming the second conductive porous layer was applied on the first conductive porous layer (1) so as to have a thickness of about 50 μm using an applicator. Then, it is dried for about 15 minutes in a drying oven set at 95 ° C. to produce the second conductive porous layer (1) on the first conductive porous layer (1), and the first conductive porous layer A laminate of the layer (1) and the second conductive porous layer (1) (battery gas diffusion layer of Example 2) was obtained.

Next, the obtained first conductive porous layer (1) included in the battery gas diffusion layer of Example 2 was placed in contact with a metal mesh (SUS304 φ0.05 × 180 m / s), and the press temperature By performing hot pressing under the conditions of 60 ° C., pressing pressure of 2 MPa, and pressing time of 180 seconds, the laminate of the first conductive porous layer (1) and the second conductive porous layer (1) and the metal mesh are obtained. An integrated battery gas diffusion layer (battery gas diffusion layer of Example 2 including a metal mesh) was produced. In this gas diffusion layer for a battery, when the first conductive porous layer (1) is positioned below the metal mesh, the first conductive porous layer (1) is 5 minutes after the metal mesh. Did not come off.

Comparative Example 1
A composition for forming a second conductive porous layer is obtained by dispersing 100 parts by mass of conductive carbon particles, 500 parts by mass of a polymer (melting mass of 50 parts by mass), and 1000 parts by mass of methyl ethyl ketone (MEK) by media dispersion. Was formulated. This composition for forming a second conductive porous layer was applied on a polyethylene terephthalate (PET) film on which a release layer was formed using an applicator so as to have a thickness of about 50 μm. Then, it was made to dry for about 15 minutes in the drying furnace set to 95 degreeC, and the 2nd electroconductive porous layer (1) was produced on PET film. Thereafter, the second conductive porous layer (1) was peeled off from the PET film on which the release layer was formed to obtain the second conductive porous layer (1) (the battery gas diffusion layer of Comparative Example 1). .

Next, the obtained 2nd electroconductive porous layer (1) is arrange | positioned on the surface of a metal mesh (SUS304 (phi) 0.05 * 180 m / s), press temperature of 200 degreeC, press pressure of 10 MPa, and press time of 180 second. By performing hot pressing under conditions, a battery gas diffusion layer (battery gas diffusion layer of Comparative Example 1 including a metal mesh) in which the second conductive porous layer (1) and the metal mesh were laminated was produced. When the second conductive porous layer (1) was placed below the metal mesh, the second conductive porous layer (1) did not peel off from the metal mesh even after 5 minutes.

Comparative Example 2
In the same manner as in Comparative Example 1, a second conductive porous layer (1) was obtained.

Next, the obtained 2nd electroconductive porous layer (1) is arrange | positioned on the surface of a metal mesh (SUS304 (phi) 0.05 * 180 m / s), the press temperature of 60 degreeC, the press pressure of 2 MPa, and the press time of 180 second. By hot pressing under the conditions, a battery gas diffusion layer (battery gas diffusion layer of Comparative Example 2 including a metal mesh) in which the second conductive porous layer (1) and the metal mesh were laminated was produced. However, the second conductive porous layer (1) is hardly adhered to the metal mesh, and immediately after the second conductive porous layer (1) is positioned below the metal mesh. Peeled off.

Example 3
In the same manner as in Example 1, a first conductive porous layer (1) was produced.

Next, the obtained 1st electroconductive porous layer (1) is arrange | positioned on the surface of the side in which the flow path of the commercially available metal separator was formed, press temperature 60 degreeC, press pressure 2MPa, press time 180 seconds. Example 3 provided with a battery member (first conductive porous layer (1) and metal separator) in which the first conductive porous layer (1) and the metal separator are integrated by hot pressing under conditions Battery member). In this battery member, when the first conductive porous layer (1) is positioned below the metal separator, the first conductive porous layer (1) peels off from the metal separator even after 5 minutes. It did not fall.

Example 4
In the same manner as in Example 1, a laminate of the first conductive porous layer (1) and the second conductive porous layer (1) was produced.

Next, the 1st electroconductive porous layer (1) which the obtained laminated body has is arrange | positioned so that the flow path of the commercially available metal separator may be formed, press temperature 60 degreeC, press pressure For a battery in which the laminate of the first conductive porous layer (1) and the second conductive porous layer (1) and the metal separator are integrated by hot pressing under conditions of 2 MPa and a press time of 180 seconds. A gas member (a battery member of Example 4 provided with a first conductive porous layer (1), a second conductive porous layer (1), and a metal separator) was produced. In this battery member, the conductive porous layers (the first conductive porous layer (1) and the second conductive porous layer (1)) are electrically conductive when placed below the metal separator. The porous layers (the first conductive porous layer (1) and the second conductive porous layer (1)) did not peel off after 5 minutes from the metal separator.

Comparative Example 3
In the same manner as in Comparative Example 1, a second conductive porous layer (1) was obtained.

Next, the obtained 2nd electroconductive porous layer (1) is arrange | positioned on the surface of the side in which the flow path of the commercially available metal separator was formed, press temperature 200 degreeC, press pressure 10MPa, press time 180 seconds. By performing hot pressing under the conditions, the battery member (second conductive porous layer (1) and metal separator) in which the second conductive porous layer (1) and the metal separator are laminated is used. Battery member) was prepared. When the second conductive porous layer (1) was placed below the metal separator, the second conductive porous layer (1) did not peel off after 5 minutes from the metal separator.

Comparative Example 4
In the same manner as in Comparative Example 1, a second conductive porous layer (1) was obtained.

Next, the obtained 2nd electroconductive porous layer (1) is arrange | positioned on the surface of the side in which the flow path of the commercially available metal separator was formed, press temperature 60 degreeC, press pressure 2MPa, press time 180 seconds. By performing hot pressing under conditions, a battery member (second conductive porous layer (1) and metal separator) in which the second conductive porous layer (1) and the metal separator are laminated is used. Battery member) was prepared. However, the second conductive porous layer (1) is hardly adhered to the metal separator, and immediately after the second conductive porous layer (1) is positioned below the metal separator. Peeled off.

Adhesion Evaluation In the gas diffusion layer or battery member for a battery comprising the metal mesh or metal separator obtained in Examples 1 to 4 and Comparative Examples 1 to 4, the adhesion between the conductive porous layer and the metal mesh or metal separator Evaluated. In particular,
A: The conductive porous layer did not peel off after 5 minutes from the metal mesh or metal separator when the conductive porous layer side was positioned below the metal mesh or metal separator. C: Conductivity When the porous layer side was positioned below the metal mesh or metal separator, it was judged that the time until the conductive porous layer peeled off from the metal mesh or metal separator was less than 5 minutes. The results are shown in Table 1.

Evaluation of change in thickness In the battery gas diffusion layer or battery member provided with the metal mesh or metal separator obtained in Examples 1 to 4 and Comparative Examples 1 to 4, the conductive porous layer was crushed in the thickness direction. Thus, it was evaluated whether or not voids were crushed. Specifically, the metal mesh or metal separator is peeled off from the battery gas diffusion layer or battery member provided with the metal mesh or metal separator obtained in Examples 1 to 4 and Comparative Examples 1 to 4, and the conductive porous layer Are observed with a scanning electron microscope (SEM),
A: Little or no change in the thickness of the conductive porous layer in contact with the metal mesh or metal separator B: 1 change in the thickness of the conductive porous layer in contact with the metal mesh or metal separator C: less than / 3: It was determined that the change in thickness of the conductive porous layer at the portion in contact with the metal mesh or metal separator was 1/3 or more. The results are shown in Table 1.

In addition, the metal mesh was peeled from the battery gas diffusion layer provided with the metal mesh obtained in Examples 1 and 2 and Comparative Example 1, and the cross section of each battery gas diffusion layer was SEM (JSM-6700F manufactured by JEOL Ltd.). ), Measure the thickness,
Crushing rate (%) = 100− (film thickness after integration) / (film thickness before integration) × 100
The crushing rate was calculated as The results are shown in Table 2.

Change in appearance of catalyst layer side surface In the battery gas diffusion layer or battery member comprising the metal mesh or metal separator obtained in Examples 1 to 4 and Comparative Examples 1 to 4, the surface of the conductive porous layer is a metal mesh or metal. It was evaluated whether it was deformed under the influence of the separator. Specifically, in the battery gas diffusion layer or battery member provided with the metal mesh or metal separator obtained in Examples 1 to 4 and Comparative Examples 1 to 4, the metal mesh or metal separator of the conductive porous layer was in contact. The surface that was not observed was observed with a scanning electron microscope (SEM),
A: There is almost no change in the appearance compared to the surface of the conductive porous layer before being integrated with the metal mesh or the metal separator. C: The conductive porous before being integrated with the metal mesh or the metal separator The change in appearance was judged to be large compared to the surface of the layer. The results are shown in Table 1.

Appearance change after substrate peeling The conductive porous layers obtained in Examples 1 to 4 and Comparative Examples 1 to 4 were evaluated for ease of peeling from the substrate. Specifically, in Examples 1 to 4 and Comparative Examples 1 to 4, when each conductive porous layer was formed on the substrate and then the substrate was peeled off,
A: No cracking occurred in the conductive porous layer C: It was judged that cracking occurred in the conductive porous layer. The results are shown in Table 1.

As a result of the above, in Examples 1 to 4, it was possible to suppress crushing of the voids of the conductive porous layer, and to be suitably integrated with the metal mesh or the metal separator. In particular, in Examples 1 and 2, the crushing ratio before and after the integration can be within the range of 0.3 to 33.3%, and the voids are crushed as compared with 48.2% in Comparative Example 1. It is suggested that it is difficult. Further, the surface of the conductive porous layer was not affected by the metal mesh or the metal separator, and cracks were not generated after the substrate was peeled off.

On the other hand, in Comparative Examples 1 and 3, the voids in the conductive porous layer are crushed because it is hot pressed under strong conditions in order to reliably integrate the conductive porous layer and the metal mesh or metal separator. In addition, the surface of the conductive porous layer is affected by the metal mesh or metal separator, and the metal mesh mark or metal separator mark is generated up to the surface of the conductive porous layer in contact with the catalyst layer, resulting in the appearance surface. Was.

In Comparative Examples 2 and 4, the conductive porous layer is sufficiently integrated with the metal mesh or the metal separator because it is hot-pressed under weak conditions to suppress the collapse of the voids of the conductive porous layer. I couldn't.

DESCRIPTION OF SYMBOLS 1 Battery gas diffusion layer 11 1st electroconductive porous layer 12 2nd electroconductive porous layer 13 Conductive porous base material 2 Battery member 21 Separator 3 Battery membrane-electrode assembly 31 Catalyst layer-electrolyte layer lamination Body 311 Electrolyte membrane 312 Catalyst layer 4 Battery

Claims

A gas diffusion layer for a battery, comprising a first conductive porous layer containing a conductive carbon material and a modified polyolefin resin.
The gas diffusion layer for a battery according to claim 1, wherein a second conductive porous layer containing a conductive carbon material and a polymer is laminated so as to be in contact with the first conductive porous layer.
The battery gas diffusion layer according to claim 2, wherein the high molecular polymer contained in the second conductive porous layer is a fluororesin.
The battery gas diffusion layer according to any one of claims 1 to 3, wherein the first conductive porous layer further contains a curing agent.
The gas diffusion layer for a battery according to any one of claims 1 to 4, wherein a conductive porous substrate is laminated so as to be in contact with the first conductive porous layer.
The battery gas diffusion layer according to any one of claims 1 to 4 is provided on one or both sides of a catalyst layer-electrolyte membrane laminate in which a catalyst layer, an electrolyte membrane, and a catalyst layer are sequentially laminated. A membrane-electrode assembly for a battery, which is laminated so that the porous layer is the outermost layer.
The gas diffusion layer for a battery according to claim 5, wherein the conductive porous substrate is an outermost layer on one side or both sides of a catalyst layer-electrolyte membrane laminate in which a catalyst layer, an electrolyte membrane, and a catalyst layer are sequentially laminated. A membrane-electrode assembly for a battery laminated in such a manner.
A battery in which a separator is further laminated so as to be in contact with the first conductive porous layer or the conductive porous substrate which is the outermost layer of the battery membrane-electrode assembly according to claim 6 or 7. .
The battery according to claim 8, wherein the separator has a porous body region.
The battery according to claim 8, wherein the separator has no gas flow path and includes a porous body.
A battery member in which a separator is laminated so as to be in contact with the first conductive porous layer of the battery gas diffusion layer according to any one of claims 1 to 4.
The battery member according to claim 11, wherein the separator has a porous body region.
The battery member according to claim 11, wherein the separator has no gas flow path and includes a porous body.
A method for producing a gas diffusion layer for a battery, comprising:
(I) a step of forming a first conductive porous layer on a substrate using a conductive carbon material and a first conductive porous layer-forming composition containing a modified polyolefin resin; and (II) The manufacturing method of the gas diffusion layer for batteries provided with the process of peeling a base material from a 1st electroconductive porous layer.
Furthermore, after the step (II),
(III) A second conductive porous layer is formed on the first conductive porous layer using a second conductive porous layer forming composition containing a conductive carbon material and a polymer. The manufacturing method of the gas diffusion layer for batteries of Claim 14 provided with a process.
Furthermore, between the step (I) and the step (II),
(III) A second conductive porous layer is formed on the first conductive porous layer using a second conductive porous layer forming composition containing a conductive carbon material and a polymer. The manufacturing method of the gas diffusion layer for batteries of Claim 14 provided with a process.
further,
(IV) The manufacturing method of the gas diffusion layer for batteries of Claim 14 or 15 provided with the process of laminating | stacking a conductive porous base material so that the said 1st conductive porous layer may be contact | connected.
Furthermore, after the step (II),
The manufacturing method of the gas diffusion layer for batteries of Claim 16 provided with the process of laminating | stacking (IV) a conductive porous base material so that the said 1st conductive porous layer may be contact | connected.
(1) A step of preparing a gas diffusion layer for a battery comprising at least a first conductive porous layer by the manufacturing method according to any one of claims 14 to 16, and (2) a separator comprising the first conductive The manufacturing method of the member for batteries provided with the process laminated | stacked so that a porous layer may be contact | connected.