JP2008300195A - Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell - Google Patents

Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell Download PDF

Info

Publication number
JP2008300195A
JP2008300195A JP2007145066A JP2007145066A JP2008300195A JP 2008300195 A JP2008300195 A JP 2008300195A JP 2007145066 A JP2007145066 A JP 2007145066A JP 2007145066 A JP2007145066 A JP 2007145066A JP 2008300195 A JP2008300195 A JP 2008300195A
Authority
JP
Japan
Prior art keywords
fuel cell
porous substrate
diffusion layer
water repellent
drying
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2007145066A
Other languages
Japanese (ja)
Inventor
Manabu Takahashi
学 高橋
Kenichi Tokuda
健一 徳田
Tsunemasa Nishida
恒政 西田
Tsutomu Ochi
勉 越智
Takahiro Nitta
高弘 新田
Shinji Matsuo
真司 松尾
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Priority to JP2007145066A priority Critical patent/JP2008300195A/en
Publication of JP2008300195A publication Critical patent/JP2008300195A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a diffusion layer for a fuel cell with high water drainage performance, and to provide a manufacturing method of a fuel cell having the diffusion layer for fuel cell. <P>SOLUTION: The manufacturing method of the diffusion layer for the fuel cell includes a coating process to coat a water repellent on a porous substrate and a drying process to dry the porous substrate coated with the water repellent. In the drying process, different drying conditions are established between one face and the other face of the porous substrate, and the concentration distribution of the water repellent in the porous substrate is controlled. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、燃料電池用拡散層の製造方法及び燃料電池の製造方法の技術に関する。   The present invention relates to a method for manufacturing a diffusion layer for a fuel cell and a technique for a method for manufacturing a fuel cell.

一般的に燃料電池は、電解質膜と電解質膜を介して配置される一対の触媒層（アノード極触媒層及びカソード極触媒層）とを含む膜−電極アッセンブリと、膜−電極アッセンブリを挟持する一対の燃料電池用拡散層（アノード極拡散層、カソード極拡散層）と、燃料電池用拡散層の両外側を挟持する一対の燃料電池用セパレータとを有する。燃料電池の発電時には、アノード極触媒層に供給するアノードガスを水素ガス、カソード極触媒層に供給するカソードガスを酸素ガスとした場合、アノード極触媒層では、水素イオンと電子とにする反応が行われ、水素イオンは電解質膜中を通りカソード極触媒層に、電子は外部回路を通じてカソード極触媒層に到達する。そして、カソード極触媒層では、水素イオン、電子及び酸素ガスが反応して水分を生成する反応が行われ、エネルギを放出する。   Generally, a fuel cell includes a membrane-electrode assembly including an electrolyte membrane and a pair of catalyst layers (an anode electrode catalyst layer and a cathode electrode catalyst layer) disposed via the electrolyte membrane, and a pair sandwiching the membrane-electrode assembly. The fuel cell diffusion layer (anode electrode diffusion layer, cathode electrode diffusion layer) and a pair of fuel cell separators sandwiching both outer sides of the fuel cell diffusion layer. During power generation of the fuel cell, when the anode gas supplied to the anode electrode catalyst layer is hydrogen gas and the cathode gas supplied to the cathode electrode catalyst layer is oxygen gas, the anode electrode catalyst layer undergoes a reaction to convert hydrogen ions and electrons. The hydrogen ions pass through the electrolyte membrane to the cathode electrode catalyst layer, and the electrons reach the cathode electrode catalyst layer through an external circuit. In the cathode electrode catalyst layer, a reaction in which hydrogen ions, electrons, and oxygen gas react to generate moisture is performed, and energy is released.

燃料電池では、電解質膜のイオン伝導性を維持するために、電解質膜に水分を含ませておく必要があり、反応ガス（アノードガス、カソードガス）は予め水分を含んだ状態で触媒層（アノード極触媒層、カソード極触媒層）に供給される。また、発電時には、上述したようにカソード極触媒層から水分が生成される。   In the fuel cell, in order to maintain the ionic conductivity of the electrolyte membrane, it is necessary to contain moisture in the electrolyte membrane, and the reaction gas (anode gas, cathode gas) is preliminarily contained in the catalyst layer (anode gas). Electrode catalyst layer, cathode electrode catalyst layer). Further, at the time of power generation, moisture is generated from the cathode electrode catalyst layer as described above.

触媒層に供給される水分及びカソード極触媒層から生成される水分のうちの一部は、燃料電池の系外へ排水されるが、上記水分のうちの一部は、触媒層及び燃料電池用拡散層に滞留する。触媒層及び燃料電池用拡散層に滞留する水分の量が多くなると、触媒層への反応ガスの供給が妨げられ、燃料電池の発電性能の低下が引き起こされる（この現象は、一般にフラッディングと呼ばれる）。そこで、触媒層又は燃料電池用拡散層の排水性を高め、触媒層又は燃料電池用拡散層内の水分の滞留を防ぎ、フラッディングの発生を抑制する必要がある。   A part of the water supplied to the catalyst layer and the water generated from the cathode electrode catalyst layer is drained out of the fuel cell system, but a part of the water is used for the catalyst layer and the fuel cell. It stays in the diffusion layer. When the amount of moisture staying in the catalyst layer and the fuel cell diffusion layer is increased, the supply of the reaction gas to the catalyst layer is hindered and the power generation performance of the fuel cell is deteriorated (this phenomenon is generally called flooding). . Therefore, it is necessary to improve the drainage of the catalyst layer or the fuel cell diffusion layer, to prevent the retention of moisture in the catalyst layer or the fuel cell diffusion layer, and to suppress the occurrence of flooding.

燃料電池用拡散層は、反応ガスを触媒層に供給するため、触媒層で生成した水分を燃料電池用セパレータに排水するために多孔質基材が用いられている。   In the fuel cell diffusion layer, a porous substrate is used to drain the water generated in the catalyst layer to the fuel cell separator in order to supply the reaction gas to the catalyst layer.

例えば、特許文献１〜４には、燃料電池用拡散層に使用される多孔質基材にポリテトラフルオロエチレン等の撥水性樹脂を塗布し、撥水性樹脂を塗布した多孔質基材を乾燥させることにより、撥水性を付与した燃料電池用拡散層の製造方法が提案されている。   For example, in Patent Documents 1 to 4, a water-repellent resin such as polytetrafluoroethylene is applied to a porous substrate used for a diffusion layer for a fuel cell, and the porous substrate coated with the water-repellent resin is dried. Thus, a method for producing a diffusion layer for a fuel cell having water repellency has been proposed.

特開２００４−１７９０９５号公報JP 2004-179095 A 特開平８−１３００１９号公報JP-A-8-130019 特開２００４−２２１０５６号公報JP 2004-221056 A 特開２００５−２３５５５６号公報JP 2005-235556 A

しかし、特許文献１〜４の燃料電池用拡散層の製造方法では、多孔質基材内の撥水性樹脂の濃度分布が制御されていないため、高い排水性を有する燃料電池用拡散層を製造することは困難である。   However, in the manufacturing method of the diffusion layer for fuel cells of Patent Documents 1 to 4, the concentration distribution of the water-repellent resin in the porous substrate is not controlled, so that the diffusion layer for fuel cells having high drainage is manufactured. It is difficult.

本発明は、排水性の高い燃料電池用拡散層の製造方法及び燃料電池の製造方法を提供することにある。   An object of the present invention is to provide a method for manufacturing a diffusion layer for a fuel cell and a method for manufacturing a fuel cell having high drainage.

本発明の燃料電池用拡散層の製造方法は、多孔質基材に撥水剤を塗布する塗布工程と、前記撥水剤を塗布した多孔質基材を乾燥する乾燥工程とを含み、前記乾燥工程において、前記多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、前記多孔質基材内の撥水剤の濃度分布を制御する。   The method for producing a diffusion layer for a fuel cell of the present invention includes a coating step of coating a porous substrate with a water repellent, and a drying step of drying the porous substrate coated with the water repellent. In the step, different drying conditions are set for one surface and the other surface of the porous substrate to control the concentration distribution of the water repellent in the porous substrate.

また、前記燃料電池用拡散層の製造方法において、前記多孔質基材内の撥水剤の濃度分布は、前記多孔質基材の一方の面から他方の面に向かって高くなるように制御されることが好ましい。   In the method for producing a diffusion layer for a fuel cell, the concentration distribution of the water repellent in the porous substrate is controlled so as to increase from one surface to the other surface of the porous substrate. It is preferable.

また、前記燃料電池用拡散層の製造方法において、前記多孔質基材の乾燥温度、前記多孔質基材に供給する風量、前記多孔質基材を乾燥する熱源と前記多孔質基材との距離のうち少なくともいずれか１つの乾燥条件が異なることが好ましい。   Further, in the method for producing a diffusion layer for a fuel cell, the drying temperature of the porous substrate, the air volume supplied to the porous substrate, the distance between the heat source for drying the porous substrate and the porous substrate It is preferable that at least any one of the drying conditions is different.

また本発明は、多孔質基材に撥水剤を塗布する塗布工程及び前記撥水剤を塗布した多孔質基材を乾燥する乾燥工程を有する燃料電池用拡散層の製造工程と、膜−電極アッセンブリの両側に前記燃料電池用拡散層の製造工程において製造された燃料電池用拡散層を配置し、前記燃料電池用拡散層の両外側に燃料電池用セパレータを配置する配置工程とを含む燃料電池の製造方法であって、前記乾燥工程において、前記多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、前記多孔質基材内の撥水剤の濃度分布を制御する。   The present invention also provides a process for producing a diffusion layer for a fuel cell comprising a coating step of applying a water repellent to a porous substrate, and a drying step of drying the porous substrate coated with the water repellent, and a membrane-electrode A fuel cell comprising: a fuel cell diffusion layer manufactured in the fuel cell diffusion layer manufacturing process on both sides of the assembly; and a fuel cell separator disposed on both outer sides of the fuel cell diffusion layer. In the drying step, different drying conditions are set on one surface and the other surface of the porous substrate to control the concentration distribution of the water repellent in the porous substrate. .

また、前記燃料電池の製造方法において、前記多孔質基材内の撥水剤の濃度分布は、前記多孔質基材の膜−電極アッセンブリ側から燃料電池用セパレータ側に向かって高くなるように制御されることが好ましい。   Further, in the fuel cell manufacturing method, the concentration distribution of the water repellent in the porous substrate is controlled to increase from the membrane-electrode assembly side of the porous substrate toward the fuel cell separator side. It is preferred that

また、前記燃料電池の製造方法において、前記多孔質基材の乾燥温度、前記多孔質基材に供給する風量、前記多孔質基材を乾燥する熱源と前記多孔質基材との距離のうち少なくともいずれか１つの乾燥条件が異なることが好ましい。   In the fuel cell manufacturing method, at least one of a drying temperature of the porous substrate, an air volume supplied to the porous substrate, and a distance between a heat source for drying the porous substrate and the porous substrate. It is preferable that any one of the drying conditions is different.

本発明によれば、多孔質基材に撥水剤を塗布する塗布工程と、撥水剤を塗布した多孔質基材を乾燥する乾燥工程とを含み、乾燥工程において、多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、多孔質基材内の撥水剤の濃度分布を制御することによって、排水性の高い燃料電池用拡散層の製造方法を提供することができる。   According to the present invention, the method includes an application step of applying a water repellent to the porous substrate, and a drying step of drying the porous substrate coated with the water repellent. By providing different drying conditions on one surface and the other surface and controlling the concentration distribution of the water repellent in the porous substrate, a method for producing a highly drainable fuel cell diffusion layer can be provided. it can.

また、本発明によれば、多孔質基材に撥水剤を塗布する塗布工程及び撥水剤を塗布した多孔質基材を乾燥する乾燥工程を有する燃料電池用拡散層の製造工程と、膜−電極アッセンブリの両側に燃料電池用拡散層の製造工程において製造された燃料電池用拡散層を配置し、燃料電池用拡散層の両外側に燃料電池用セパレータを配置する配置工程とを含む燃料電池の製造方法であって、乾燥工程において、多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、多孔質基材内の撥水剤の濃度分布を制御することによって、排水性の高い燃料電池の製造方法を提供することができる。   In addition, according to the present invention, a manufacturing process of a diffusion layer for a fuel cell having a coating step of applying a water repellent to a porous substrate and a drying step of drying the porous substrate coated with the water repellent, and a membrane A fuel cell comprising: a fuel cell diffusion layer manufactured in the fuel cell diffusion layer manufacturing process on both sides of the electrode assembly; and a fuel cell separator disposed on both outer sides of the fuel cell diffusion layer. In the drying process, by setting different drying conditions on one side and the other side of the porous substrate, and controlling the concentration distribution of the water repellent in the porous substrate, A method for producing a highly drainable fuel cell can be provided.

本発明の実施の形態について以下説明する。   Embodiments of the present invention will be described below.

図１は、本発明の実施形態に係る燃料電池用拡散層の製造方法の一例を説明するための図である。図１に示すように、本発明の実施形態に係る燃料電池用拡散層１の製造方法は、多孔質基材１０に撥水剤を塗布する塗布工程と、撥水剤を塗布した多孔質基材１０を乾燥する乾燥工程とを有するものである。   FIG. 1 is a diagram for explaining an example of a method for manufacturing a diffusion layer for a fuel cell according to an embodiment of the present invention. As shown in FIG. 1, the manufacturing method of the fuel cell diffusion layer 1 according to the embodiment of the present invention includes a coating step of applying a water repellent to the porous substrate 10 and a porous substrate coated with the water repellent. A drying step of drying the material 10.

＜塗布工程＞
塗布工程では、多孔質基材１０に撥水剤が塗布される。撥水剤は、撥水性を有する液体であれば特に制限されるものではないが、例えば、カーボン粒子及びフッ素樹脂を、水、パーフルオロベンゼン、ジクロロペンタフルオロプロパン、メタノール、エタノール等の有機溶媒等の溶媒中に分散することにより調製される。撥水剤は、撥水性樹脂が含有されていればよいが、本実施形態の製造方法により得られる燃料電池用拡散層１の電子伝導性を維持することができる点で、カーボン粒子等が含有されていることが好ましい。 <Application process>
In the application step, a water repellent is applied to the porous substrate 10. The water repellent is not particularly limited as long as it is a liquid having water repellency. For example, carbon particles and fluororesin may be used as an organic solvent such as water, perfluorobenzene, dichloropentafluoropropane, methanol, and ethanol. It is prepared by dispersing in a solvent. The water-repellent agent only needs to contain a water-repellent resin, but carbon particles and the like are contained in that the electron conductivity of the fuel cell diffusion layer 1 obtained by the production method of the present embodiment can be maintained. It is preferable that

撥水性樹脂は、燃料電池用拡散層１において一般的に用いられるものであれば特に制限されるものではないが、撥水性、耐腐食性等を有するフッ素樹脂が好ましい。フッ素樹脂は、例えば、ポリテトラフルオロエチレン、ポリフッ化ビニリデン、ポリヘキサフルオロプロピレン、テトラフルオロエチレン−ヘキサフルオロプロピレン共重合体等が挙げられる。   The water-repellent resin is not particularly limited as long as it is generally used in the diffusion layer 1 for fuel cells, but a fluororesin having water repellency, corrosion resistance and the like is preferable. Examples of the fluororesin include polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, tetrafluoroethylene-hexafluoropropylene copolymer, and the like.

カーボン粒子等は、燃料電池用拡散層１において一般的に用いられるものであれば特に制限されるものではない。カーボン粒子は、例えば、オイルファーネスブラック、チャネルブラック、ランプブラック、サーマルブラック等のカーボンブラック、黒鉛、カーボンナノチューブ等が挙げられる。また、カーボン粒子に限られるものではなく、カーボン繊維等であってもよい。   The carbon particles and the like are not particularly limited as long as they are generally used in the fuel cell diffusion layer 1. Examples of the carbon particles include carbon black such as oil furnace black, channel black, lamp black, and thermal black, graphite, and carbon nanotube. Moreover, it is not restricted to a carbon particle, A carbon fiber etc. may be sufficient.

撥水性樹脂の含有量は、特に制限されるものではないが、カーボン粒子等の重量に対して５〜４０重量％の範囲であることが好ましい。   The content of the water repellent resin is not particularly limited, but is preferably in the range of 5 to 40% by weight with respect to the weight of the carbon particles and the like.

また、本実施形態に用いられる撥水剤には、界面活性剤等が含まれていてもよい。界面活性剤は、例えば、アルキルエーテル、アルキルフェニルエーテル、ポリオキシエチレンアルキルエーテル等の非イオン性界面活性剤等が挙げられる。   Further, the water repellent used in this embodiment may contain a surfactant or the like. Examples of the surfactant include nonionic surfactants such as alkyl ether, alkylphenyl ether, and polyoxyethylene alkyl ether.

多孔質基材１０は、燃料電池用拡散層１において一般的に用いられるものであれば特に制限されるものではないが、燃料電池に供給される反応ガス（アノードガス、カソードガス）の透過性、導電性等の点で、カーボンペーパ等のカーボン不織布、カーボンクロス等のカーボン織布等が好ましい。   The porous substrate 10 is not particularly limited as long as it is generally used in the fuel cell diffusion layer 1, but the permeability of the reaction gas (anode gas, cathode gas) supplied to the fuel cell is not limited. From the viewpoint of conductivity, carbon non-woven fabric such as carbon paper, carbon woven fabric such as carbon cloth and the like are preferable.

多孔質基材１０に撥水剤を塗布する方法は、フローコーティング法、スプレー法、スクリーン印刷法、ドクターブレード法等公知の方法が挙げられる。また、塗布回数、塗布速度等は適宜設定すればよい。   Examples of the method for applying the water repellent to the porous substrate 10 include known methods such as a flow coating method, a spray method, a screen printing method, and a doctor blade method. Moreover, what is necessary is just to set suitably the frequency | count of application | coating, a coating speed, etc.

＜乾燥工程＞
乾燥工程では、上記撥水剤を塗布した多孔質基材１０の一方の面（図１に示すＡ面）と他方の面（図１に示すＢ面）とで異なる乾燥条件を設定し、多孔質基材１０内の撥水剤の濃度分布を制御して、撥水剤を塗布した多孔質基材１０を乾燥させる。 <Drying process>
In the drying step, different drying conditions are set on one surface (surface A shown in FIG. 1) and the other surface (surface B shown in FIG. 1) of the porous substrate 10 coated with the water repellent agent, The porous substrate 10 coated with the water repellent is dried by controlling the concentration distribution of the water repellent in the porous substrate 10.

撥水剤を塗布した多孔質基材１０の乾燥は、赤外線照射、電磁波照射、ドライエア、ヒータ等による乾燥等の公知の方法により行われる。   The porous substrate 10 coated with the water repellent is dried by a known method such as infrared irradiation, electromagnetic wave irradiation, dry air, drying with a heater or the like.

本実施形態では、多孔質基材１０の一方の面（例えば、図１に示すＡ面）と他方の面（例えば、図１に示すＢ面）とで、後述する異なる乾燥条件を設定し乾燥させる。例えば、図１に示す多孔質基材１０のＡ面とＢ面とで異なる乾燥温度を設定することによって、多孔質基材１０のＡ面とＢ面との乾燥状態を異ならせることができる。多孔質基材１０のＡ面とＢ面とで乾燥状態が異なると、乾燥状態の遅い方から乾燥状態の早い方に向かって、撥水剤（主に撥水性樹脂）がマイグレーションするため、撥水剤の濃度分布が生じる。すなわち、多孔質基材１０のＡ面とＢ面とで異なる乾燥条件を設定することにより、多孔質基材１０のＡ面とＢ面との乾燥状態を異ならせ、多孔質基材１０内の撥水剤の濃度分布（主に撥水性樹脂の濃度分布）を制御することができる。   In the present embodiment, drying is performed by setting different drying conditions to be described later on one surface (for example, the A surface shown in FIG. 1) and the other surface (for example, the B surface shown in FIG. 1) of the porous substrate 10. Let For example, by setting different drying temperatures for the A surface and the B surface of the porous substrate 10 shown in FIG. 1, the drying states of the A surface and the B surface of the porous substrate 10 can be made different. Since the water repellent (mainly water repellent resin) migrates from the slower dry state to the faster dry state when the dry state is different between the A surface and the B surface of the porous substrate 10, A concentration distribution of liquid medication occurs. That is, by setting different drying conditions for the A surface and the B surface of the porous base material 10, the dry state of the A surface and the B surface of the porous base material 10 is made different. The concentration distribution of the water repellent (mainly the concentration distribution of the water repellent resin) can be controlled.

本実施形態では、多孔質基材１０の一方の面から他方の面に向かって撥水剤の濃度（主に撥水性樹脂）が高くなるように、多孔質基材１０の一方の面と他方の面とで異なる乾燥条件を設定することが好ましい。例えば、図１に示す多孔質基材１０のＡ面からＢ面に向かって撥水剤の濃度分布を高くすることによって、多孔質基材１０のＡ面側にある水分の吸い上げ効果を向上させることができる。また、撥水剤濃度の高い多孔質基材１０のＢ面では、接触角、転落角も高いため、多孔質基材１０のＢ面付近で水分が滞留することを抑制することができる。   In the present embodiment, the one surface and the other surface of the porous substrate 10 are so arranged that the concentration of the water repellent (mainly water-repellent resin) increases from one surface of the porous substrate 10 to the other surface. It is preferable to set different drying conditions depending on the surface. For example, by increasing the concentration distribution of the water repellent from the A surface to the B surface of the porous substrate 10 shown in FIG. 1, the effect of sucking up moisture on the A surface side of the porous substrate 10 is improved. be able to. Further, since the contact angle and the falling angle are high on the B surface of the porous substrate 10 having a high water repellent concentration, it is possible to suppress moisture from being retained near the B surface of the porous substrate 10.

上記でも説明したように、本実施形態では異なる乾燥条件を設定し、多孔質基材１０内の撥水剤の濃度分布を制御する。例えば、一方の面と他方の面とで異なる乾燥温度、昇温速度、供給する風量、多孔質基材１０を乾燥させるための熱源と多孔質基材との距離等のうち少なくともいずれか１つの乾燥条件を設定し、多孔質基材１０内の撥水剤の濃度分布を制御する。撥水剤の濃度分布の制御が容易である等の点で、異なる乾燥条件は、上記乾燥温度、風量、熱源と多孔質基材との距離であることが好ましい。   As described above, in this embodiment, different drying conditions are set to control the concentration distribution of the water repellent in the porous substrate 10. For example, at least one of a drying temperature, a heating rate, an air flow to be supplied, a distance between a heat source for drying the porous substrate 10 and the porous substrate, and the like, which are different between one surface and the other surface Drying conditions are set, and the concentration distribution of the water repellent in the porous substrate 10 is controlled. In terms of easy control of the concentration distribution of the water repellent, the different drying conditions are preferably the drying temperature, the air volume, and the distance between the heat source and the porous substrate.

上記乾燥条件のうち、多孔質基材１０の一方の面と他方の面とで異なる乾燥温度は、一方の面と他方の面とで乾燥状態を異ならせることができる温度差に設定されるものであればよいが、撥水剤のマイグレーションが発生し易い等の点で、乾燥温度差が、常温〜２３０℃の範囲であることが好ましく、６０〜２３０℃の範囲であることがより好ましい。上記でも説明したように、撥水剤のマイグレーションは、乾燥状態の遅い方から速い方に向かって起こる。したがって、異なる乾燥温度の場合における撥水剤のマイグレーションは、乾燥温度の低い面から高い面に向かって起こる。すなわち、乾燥温度の低い面から高い面に向かって撥水剤の濃度分布が高くなる。   Among the above drying conditions, the drying temperature that is different between one surface and the other surface of the porous substrate 10 is set to a temperature difference that allows the drying state to be different between the one surface and the other surface. However, the drying temperature difference is preferably in the range of room temperature to 230 ° C., more preferably in the range of 60 to 230 ° C. in terms of easy migration of the water repellent. As described above, the migration of the water repellent occurs from the slower to the faster dry state. Therefore, the migration of the water repellent at different drying temperatures occurs from the lower surface to the higher surface. That is, the concentration distribution of the water repellent increases from the surface having a low drying temperature toward the surface having a high drying temperature.

また、一方の面及び他方の面での乾燥温度の範囲（上限、下限）は、特に制限されるものではないが、撥水剤中の水、有機溶媒が蒸発する温度以上かつ撥水剤中の撥水性樹脂の溶融温度未満の範囲が好ましい。   Moreover, the range (upper limit, lower limit) of the drying temperature on one side and the other side is not particularly limited, but is higher than the temperature at which water in the water repellent, the organic solvent evaporates and in the water repellent. A range below the melting temperature of the water repellent resin is preferred.

また、上記乾燥条件のうち、多孔質基材１０の一方の面と他方の面とで異なる昇温速度は、多孔質基材１０の一方の面と他方の面とで乾燥状態を異ならせることができる昇温速度の差に設定されるものであればよい。撥水剤のマイグレーションは、昇温速度の遅い面から早い面に向かって起こる。   Further, among the above drying conditions, the heating rate that is different between one surface and the other surface of the porous substrate 10 is such that the dry state differs between the one surface and the other surface of the porous substrate 10. As long as it is set to the difference in the rate of temperature increase that can be achieved. The migration of the water repellent agent occurs from the slow surface to the fast surface.

また、ドライエアを供給することにより多孔質基材１０を乾燥させる場合等では、上記乾燥条件のうち、多孔質基材１０の一方の面と他方の面とで異なる風量は、多孔質基材１０の一方の面と他方の面とで乾燥状態を異ならせることができる風量差に設定されるものであればよい。撥水剤のマイグレーションは、風量の小さい方から大きいほうに向かって起こる。   Further, in the case of drying the porous substrate 10 by supplying dry air, etc., the air volume that is different between one surface and the other surface of the porous substrate 10 among the above drying conditions is the porous substrate 10. What is necessary is just to set it as the air volume difference which can make a dry state different in one side and the other side. Migration of the water repellent occurs from the smaller air volume to the larger air volume.

また、赤外線照射等により多孔質基材１０を乾燥させる場合等では、上記乾燥条件のうち、図１に示す熱源１２（多孔質基材１０を乾燥させるために赤外線照射等をするもの）と多孔質基材１０の一方の面との距離Ｌ１と、熱源１２と多孔質基材１０の他方の面との距離Ｌ２は、多孔質基材１０の一方の面と他方の面とで乾燥状態を異ならせることができる差であればよい。なお、撥水剤のマイグレーションは、距離が長い方から短い方に向かって起こる。   In the case of drying the porous substrate 10 by infrared irradiation or the like, among the above drying conditions, the heat source 12 shown in FIG. 1 (which performs infrared irradiation or the like to dry the porous substrate 10) and porous The distance L1 between one surface of the porous base material 10 and the distance L2 between the heat source 12 and the other surface of the porous base material 10 indicate a dry state between the one surface and the other surface of the porous base material 10. Any difference that can be made different is acceptable. The migration of the water repellent occurs from the longer distance to the shorter distance.

上記乾燥工程後に、多孔質基材１０を焼成等することによって、燃料電池用拡散層１が得られる。多孔質基材１０の焼成は、必ずしも必要ではないが、多孔質基材１０中に撥水剤を安定に保持させることができる点で好ましい。多孔質基材１０への焼成温度は、特に制限されるものではないが、撥水剤中の撥水性樹脂の溶融温度以上かつ分解温度未満であることが好ましい。   After the drying step, the fuel cell diffusion layer 1 is obtained by firing the porous substrate 10 or the like. Firing of the porous substrate 10 is not always necessary, but is preferable in that the water repellent can be stably held in the porous substrate 10. The firing temperature for the porous substrate 10 is not particularly limited, but is preferably not less than the melting temperature and less than the decomposition temperature of the water-repellent resin in the water-repellent agent.

次に、撥水剤を有する多孔質基材を複数積層した場合の本実施形態に係る燃料電池用の燃料電池用拡散層の製造方法の一例について説明する。   Next, an example of a method for producing a fuel cell diffusion layer for a fuel cell according to this embodiment when a plurality of porous substrates having a water repellent agent are laminated will be described.

図２は、本発明の他の実施形態に係る燃料電池用拡散層の製造方法の一例を説明するための図である。まず、1層目の多孔質基材１０ａに、上記説明した塗布工程、乾燥工程を行う。乾燥工程において、多孔質基材１０ａのＡ面からＢ面に向かって撥水剤の濃度分布を高くする場合には、多孔質基材１０ａのＡ面の温度よりＢ面の温度を高くする（昇温速度、風量等であってもよい）。次に、２層目の多孔質基材１０ｂを１層目の多孔質基材１０ａのＡ面に配置した後、上記説明した塗布工程、乾燥工程を行う。乾燥工程において、多孔質基材１０ａ，１０ｂを積層した多孔質基材１０ｃのＣ面からＤ面（Ｄ面は、多孔質基材１０ａのＢ面）に向かって撥水剤の濃度分布を高くする場合には、多孔質基材１０ｃのＣ面の温度よりＤ面の温度を高くする（昇温速度、風量等であってもよい）。なお、１層目の多孔質基材１０ａに加える温度及び多孔質基材１０ｃに加える温度は、Ｃ面＜Ａ面＜Ｄ面＜Ｂ面の順で高くする。好ましくは、Ｃ面とＤ面との温度差が６０℃以上である。   FIG. 2 is a diagram for explaining an example of a method for manufacturing a diffusion layer for a fuel cell according to another embodiment of the present invention. First, the coating process and the drying process described above are performed on the first porous substrate 10a. In the drying step, when the concentration distribution of the water repellent is increased from the A surface to the B surface of the porous substrate 10a, the temperature of the B surface is set higher than the temperature of the A surface of the porous substrate 10a ( It may be a heating rate, an air volume, etc.). Next, after the second-layer porous substrate 10b is disposed on the A surface of the first-layer porous substrate 10a, the above-described application step and drying step are performed. In the drying step, the concentration distribution of the water repellent is increased from the C surface of the porous substrate 10c in which the porous substrates 10a and 10b are laminated to the D surface (the D surface is the B surface of the porous substrate 10a). When doing so, the temperature of the D surface is made higher than the temperature of the C surface of the porous substrate 10c (may be a temperature rise rate, an air volume, etc.). Note that the temperature applied to the porous substrate 10a of the first layer and the temperature applied to the porous substrate 10c are increased in the order of C plane <A plane <D plane <B plane. Preferably, the temperature difference between the C plane and the D plane is 60 ° C. or more.

塗布工程、乾燥工程は、必ずしも上記に限定されるものではなく、例えば、1層目の多孔質基材１０ａ、２層目の多孔質基材１０ｂに撥水剤を塗布した（上記説明した塗布工程）後、1層目の多孔質基材１０ａ、２層目の多孔質基材１０ｂを積層して、積層した多孔質基材１０ｃを乾燥させる（上記説明した乾燥工程）ものであってもよい。   The application step and the drying step are not necessarily limited to the above. For example, a water repellent agent is applied to the first porous substrate 10a and the second porous substrate 10b (the application described above). Step) After that, the first-layer porous substrate 10a and the second-layer porous substrate 10b are laminated, and the laminated porous substrate 10c is dried (the above-described drying step). Good.

通常、撥水剤を有する多孔質基材を複数積層した燃料電池用拡散層では、積層される多孔質基材毎に、撥水性樹脂、カーボン粒子の含有量を変えた撥水剤を含有させることにより、層毎の撥水剤の濃度分布を制御するものである。本実施形態では、層毎の撥水剤の濃度分布を制御するだけでなく、各多孔質基材内の撥水剤の濃度分布を制御することができる。   Usually, in a fuel cell diffusion layer in which a plurality of porous base materials having a water repellent agent are laminated, a water repellent agent in which the water repellent resin and the carbon particle content are changed is included in each laminated porous base material. Thus, the concentration distribution of the water repellent agent for each layer is controlled. In this embodiment, not only the concentration distribution of the water repellent agent for each layer but also the concentration distribution of the water repellent agent in each porous substrate can be controlled.

以上のように、本実施形態に係る燃料電池用拡散層の製造方法では、撥水剤を塗布した多孔質基材を乾燥する乾燥工程において、多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、多孔質基材内の撥水剤の濃度分布を制御することにより、排水性の高い燃料電池用拡散層を製造することができる。特に、多孔質基材の一方の面から他方の面に向かって撥水剤の濃度分布が高くなるように制御することによって、多孔質基材の一方の面から他方の面に向かって撥水性を高くすることができる。これによって、水分の吸い上げ効果を高くすることができ、また、多孔質基材内の水分の滞留を抑制することができる。   As described above, in the method for manufacturing a diffusion layer for a fuel cell according to the present embodiment, in the drying step of drying the porous substrate coated with the water repellent agent, one surface and the other surface of the porous substrate are By setting different drying conditions and controlling the concentration distribution of the water repellent in the porous substrate, a fuel cell diffusion layer with high drainage can be produced. In particular, by controlling so that the concentration distribution of the water repellent increases from one surface of the porous substrate toward the other surface, the water repellency from one surface of the porous substrate toward the other surface. Can be high. Thereby, the effect of sucking up moisture can be increased, and the retention of moisture in the porous substrate can be suppressed.

次に、本実施形態に係る燃料電池の製造方法について説明する。   Next, a method for manufacturing the fuel cell according to this embodiment will be described.

図３は、本実施形態に係る燃料電池の製造方法の一例を説明するための図である。図３に示すように、本実施形態に係る燃料電池２の製造方法は、上記説明した多孔質基材１０に撥水剤を塗布する塗布工程及び前記撥水剤を塗布した多孔質基材１０を乾燥する乾燥工程を有する燃料電池用拡散層の製造工程と、膜−電極アッセンブリ１４の両側に上記燃料電池用拡散層の製造工程において製造された燃料電池用拡散層１を配置し、燃料電池用拡散層１の両外側に燃料電池用セパレータ１６を配置する配置工程とを含むものである。   FIG. 3 is a diagram for explaining an example of a method for manufacturing a fuel cell according to the present embodiment. As shown in FIG. 3, the manufacturing method of the fuel cell 2 according to the present embodiment includes a coating step of applying a water repellent to the porous substrate 10 described above, and a porous substrate 10 coated with the water repellent. The fuel cell diffusion layer 1 manufactured in the fuel cell diffusion layer manufacturing process is disposed on both sides of the membrane-electrode assembly 14 and the fuel cell diffusion layer 1 is dried. And a disposing step of disposing the fuel cell separator 16 on both outer sides of the diffusion layer 1.

＜塗布工程＞
塗布工程は、上記同様に多孔質基材１０に撥水剤が塗布される。撥水剤の組成、塗布方法等は上記説明した通りである。 <Application process>
In the application step, a water repellent is applied to the porous substrate 10 as described above. The composition and application method of the water repellent are as described above.

＜乾燥工程＞
乾燥工程では、上記同様に上記撥水剤を塗布した多孔質基材１０の一方の面と他方の面とで異なる乾燥条件を設定し、多孔質基材１０内の撥水剤の濃度分布を制御して、撥水剤を塗布した多孔質基材１０を乾燥させる。 <Drying process>
In the drying step, different drying conditions are set for one surface and the other surface of the porous substrate 10 coated with the water repellent as described above, and the concentration distribution of the water repellent in the porous substrate 10 is determined. The porous substrate 10 coated with the water repellent is dried by controlling.

燃料電池の発電時に生成する水分は、触媒層２０から燃料電池用拡散層１を通り、燃料電池用セパレータ１６へ排水される。したがって、燃料電池用拡散層１は、触媒層２０内の水分を吸い上げて、吸い上げた水分を燃料電池用セパレータ１６側付近の燃料電池用拡散層１内で滞留させることなく、燃料電池用セパレータ１６へ排水させる必要がある。   Moisture generated during power generation of the fuel cell passes through the fuel cell diffusion layer 1 from the catalyst layer 20 and is drained to the fuel cell separator 16. Therefore, the fuel cell diffusion layer 1 sucks up the moisture in the catalyst layer 20, and does not retain the sucked up moisture in the fuel cell diffusion layer 1 near the fuel cell separator 16 side. It is necessary to drain the water.

例えば、図３に示すように、多孔質基材１０のＡ面に、触媒層２０が配置され、多孔質基材１０のＢ面に燃料電池用セパレータ１６が配置される（後述する配置工程）場合、触媒層２０側の多孔質基材１０のＡ面から燃料電池用セパレータ１６側の多孔質基材１０のＢ面に向かって、撥水剤の濃度分布が高くなるように乾燥条件を設定することが好ましい。乾燥条件は上記説明した通りであるが、例えば、多孔質基材１０のＡ面より多孔質基材１０のＢ面の乾燥温度を高くする（例えば、Ａ面よりＢ面の乾燥温度を６０℃高くする）ことによって、多孔質基材１０のＡ面から多孔質基材１０のＢ面に向かって、撥水剤がマイグレーションし、撥水剤の濃度を高くすることができる。   For example, as shown in FIG. 3, the catalyst layer 20 is disposed on the A surface of the porous substrate 10, and the fuel cell separator 16 is disposed on the B surface of the porous substrate 10 (arrangement step described later). In this case, the drying condition is set so that the concentration distribution of the water repellent increases from the A surface of the porous substrate 10 on the catalyst layer 20 side toward the B surface of the porous substrate 10 on the fuel cell separator 16 side. It is preferable to do. The drying conditions are as described above. For example, the drying temperature of the B surface of the porous substrate 10 is set higher than the A surface of the porous substrate 10 (for example, the drying temperature of the B surface is set to 60 ° C. from the A surface). The water repellent migrates from the A surface of the porous substrate 10 toward the B surface of the porous substrate 10, thereby increasing the concentration of the water repellent.

触媒層２０側の多孔質基材１０の面から燃料電池用セパレータ１６側の多孔質基材１の面に向かって、撥水剤の濃度を高くし、撥水性を向上させることによって、触媒層２０内の水分の吸い上げ効果を高くすることができる。さらに、燃料電池用セパレータ１６側の多孔質基材１０の面は撥水性が高いため、接触角、転落角も高い。したがって、燃料電池用セパレータ１６側付近の燃料電池用拡散層１内で水分が滞留することを抑制することができる。   By increasing the water repellent concentration and improving the water repellency from the surface of the porous substrate 10 on the catalyst layer 20 side toward the surface of the porous substrate 1 on the fuel cell separator 16 side, the catalyst layer is improved. The effect of sucking up moisture in 20 can be increased. Furthermore, since the surface of the porous substrate 10 on the fuel cell separator 16 side has high water repellency, the contact angle and the falling angle are also high. Therefore, it is possible to suppress moisture from staying in the fuel cell diffusion layer 1 near the fuel cell separator 16 side.

＜配置工程＞
配置工程では、膜−電極アッセンブリ１４の両側に上記塗布工程、乾燥工程を有する燃料電池用拡散層の製造工程において製造された燃料電池用拡散層１を配置し、さらに燃料電池用拡散層１の両外側に燃料電池用セパレータ１６を配置する。 <Arrangement process>
In the disposing step, the fuel cell diffusion layer 1 manufactured in the manufacturing step of the fuel cell diffusion layer having the coating step and the drying step is disposed on both sides of the membrane-electrode assembly 14. Fuel cell separators 16 are disposed on both outer sides.

膜−電極アッセンブリ１４は、電解質膜１８と、電解質膜１８を挟持する一対の触媒層２０とを有する。   The membrane-electrode assembly 14 includes an electrolyte membrane 18 and a pair of catalyst layers 20 that sandwich the electrolyte membrane 18.

電解質膜１８は、プロトン伝導性を有する膜であり、例えば、パーフルオロスルホン酸膜、エチレン−四フッ化エチレン共重合体樹脂膜、トリフルオロスチレンをベースポリマーとする樹脂膜などのフッ素系高分子電解質膜や、スルホン酸基を有する炭化水素系樹脂系膜等が挙げられる。   The electrolyte membrane 18 is a membrane having proton conductivity. For example, a fluorine-based polymer such as a perfluorosulfonic acid membrane, an ethylene-tetrafluoroethylene copolymer resin membrane, or a resin membrane containing trifluorostyrene as a base polymer. Examples thereof include an electrolyte membrane and a hydrocarbon resin membrane having a sulfonic acid group.

触媒層２０には、アノード極側に配置されるアノード極触媒層と、カソード極側に配置されるカソード極触媒層とがある。触媒層２０（アノード極触媒層、カソード極触媒層）は、例えば、白金、ルテニウム等の金属触媒を担持したカーボンと電解質等とを混合して、燃料電池用拡散層１又は電解質膜１８上に成膜することにより形成される。本実施形態で使用される電解質としては、プロトン電導性を有するものであり、例えば、パーフルオロカーボンスルホン酸系ポリマー、ポリトリフルオロスチレンスルフォン酸系ポリマー、パーフルオロスルホン酸系ポリマー、パーフルオロカーボンホスホン酸系ポリマー、トリフルオロスチレンスルホン酸系ポリマー等が挙げられる。   The catalyst layer 20 includes an anode electrode catalyst layer disposed on the anode electrode side and a cathode electrode catalyst layer disposed on the cathode electrode side. The catalyst layer 20 (anode electrode catalyst layer, cathode electrode catalyst layer) is formed on the fuel cell diffusion layer 1 or the electrolyte membrane 18 by mixing, for example, carbon carrying a metal catalyst such as platinum or ruthenium and an electrolyte. It is formed by forming a film. The electrolyte used in the present embodiment has proton conductivity, for example, perfluorocarbon sulfonic acid polymer, polytrifluorostyrene sulfonic acid polymer, perfluorosulfonic acid polymer, perfluorocarbon phosphonic acid. Examples thereof include polymers and trifluorostyrene sulfonic acid polymers.

燃料電池用拡散層１には、アノード極側に配置されるアノード極拡散層と、カソード極側に配置されるカソード極拡散層とがある。本実施形態において、上記説明した塗布工程、乾燥工程を有する燃料電池用拡散層の製造方法により得られる燃料電池用拡散層１は、アノード極拡散層又はカソード極拡散層のうち少なくともいずれか一方でよい。しかし、燃料電池の発電により生成する水分は、主にカソード極側であるため、少なくともカソード極拡散層は、本実施形態に掛かる燃料電池用拡散層の製造方法により得られたものであることが好ましく、また、燃料電池の排水性の点で、アノード極拡散層及びカソード極拡散層の両方とも、本実施形態に掛かる燃料電池用拡散層の製造方法により得られたものであることがより好ましい。   The fuel cell diffusion layer 1 includes an anode electrode diffusion layer disposed on the anode electrode side and a cathode electrode diffusion layer disposed on the cathode electrode side. In the present embodiment, the fuel cell diffusion layer 1 obtained by the method for producing a fuel cell diffusion layer having the application step and the drying step described above is at least one of an anode electrode diffusion layer and a cathode electrode diffusion layer. Good. However, since the water generated by the power generation of the fuel cell is mainly on the cathode side, at least the cathode diffusion layer is obtained by the method for manufacturing a diffusion layer for a fuel cell according to this embodiment. Preferably, both the anode electrode diffusion layer and the cathode electrode diffusion layer are more preferably obtained by the method for manufacturing a fuel cell diffusion layer according to the present embodiment in terms of drainage of the fuel cell. .

燃料電池用セパレータ１６には、アノード極側に配置されるアノード極セパレータと、カソード極側に配置されるカソード極セパレータとがある。燃料電池用セパレータ１６（アノード極セパレータ、カソード極セパレータ）の空洞部は、反応ガスが流れる反応ガス流路２２である。なお、アノード極セパレータの反応ガス流路には、アノードガスが流れ、カソード極セパレータの反応ガス流路には、カソードガスが流れる。燃料電池用セパレータ１６は、例えば、ステンレス板等の金属系セパレータ、黒鉛板等のカーボン系セパレータ等が使用される。   The fuel cell separator 16 includes an anode electrode separator disposed on the anode electrode side and a cathode electrode separator disposed on the cathode electrode side. The cavity of the fuel cell separator 16 (anode electrode separator, cathode electrode separator) is a reaction gas flow path 22 through which reaction gas flows. The anode gas flows in the reaction gas flow path of the anode separator, and the cathode gas flows in the reaction gas flow path of the cathode separator. As the fuel cell separator 16, for example, a metal separator such as a stainless steel plate, a carbon separator such as a graphite plate, or the like is used.

以上のように、本実施形態に係る燃料電池の製造方法では、撥水剤を塗布した多孔質基材を乾燥する乾燥工程において、多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、多孔質基材内の撥水剤の濃度分布を制御することにより、排水性の高い燃料電池を製造することができる。特に、多孔質基材の触媒層側の面から燃料電池用セパレータ側の面に向かって、撥水剤の濃度分布が高くなるように制御することによって、触媒層側の面から燃料電池用セパレータ側の面に向かって排水性を高くすることができる。これによって、触媒層内の水分の吸い上げ効果を高くすることができる。また、多孔質基材の燃料電池用セパレータ側の面は撥水性が高いため、接触角、転落角も高い。したがって、燃料電池用セパレータ側付近で水分が滞留することを抑制することができる。   As described above, in the fuel cell manufacturing method according to the present embodiment, in the drying step of drying the porous substrate coated with the water repellent, different drying is performed on one surface of the porous substrate and the other surface. By setting the conditions and controlling the concentration distribution of the water repellent in the porous substrate, a fuel cell with high drainage can be produced. In particular, by controlling the concentration distribution of the water repellent from the surface on the catalyst layer side of the porous substrate toward the surface on the fuel cell separator side, the separator for the fuel cell from the surface on the catalyst layer side. The drainage can be increased toward the side surface. Thereby, the effect of sucking up moisture in the catalyst layer can be enhanced. Further, since the surface of the porous substrate on the fuel cell separator side has high water repellency, the contact angle and the falling angle are also high. Therefore, it is possible to suppress moisture from being retained in the vicinity of the fuel cell separator side.

本実施形態の燃料電池の製造方法により得られる燃料電池は、例えば、携帯電話、携帯用パソコン等のモバイル機器用小型電源、自動車用電源、家庭用電源等として使用することができる。   The fuel cell obtained by the fuel cell manufacturing method of the present embodiment can be used as, for example, a small power source for mobile devices such as a mobile phone and a portable personal computer, a power source for automobiles, and a household power source.

本発明の実施形態に係る燃料電池用拡散層の製造方法の一例を説明するための図である。It is a figure for demonstrating an example of the manufacturing method of the diffusion layer for fuel cells which concerns on embodiment of this invention. 本発明の他の実施形態に係る燃料電池用拡散層の製造方法の一例を説明するための図である。It is a figure for demonstrating an example of the manufacturing method of the diffusion layer for fuel cells which concerns on other embodiment of this invention. 本実施形態に係る燃料電池の製造方法の一例を説明するための図である。It is a figure for demonstrating an example of the manufacturing method of the fuel cell which concerns on this embodiment.

符号の説明Explanation of symbols

１ 燃料電池用拡散層、２ 燃料電池、１０，１０ａ〜１０ｃ 多孔質基材、１２ 熱源、１４ 膜−電極アッセンブリ、１６ 燃料電池用セパレータ、１８ 電解質膜、２０ 触媒層、２２ 反応ガス流路。   DESCRIPTION OF SYMBOLS 1 Diffusion layer for fuel cells, 2 Fuel cell, 10, 10a-10c Porous base material, 12 Heat source, 14 Membrane-electrode assembly, 16 Separator for fuel cells, 18 Electrolyte membrane, 20 Catalyst layer, 22 Reaction gas flow path.

Claims (6)

多孔質基材に撥水剤を塗布する塗布工程と、前記撥水剤を塗布した多孔質基材を乾燥する乾燥工程とを含み、
前記乾燥工程において、前記多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、前記多孔質基材内の撥水剤の濃度分布を制御することを特徴とする燃料電池用拡散層の製造方法。 An application step of applying a water repellent to the porous substrate, and a drying step of drying the porous substrate coated with the water repellent,
In the drying step, a different drying condition is set for one surface and the other surface of the porous base material, and the concentration distribution of the water repellent in the porous base material is controlled. For producing a diffusion layer for use. 請求項１記載の燃料電池用拡散層の製造方法であって、前記多孔質基材内の撥水剤の濃度分布は、前記多孔質基材の一方の面から他方の面に向かって高くなるように制御されることを特徴とする燃料電池用拡散層の製造方法。   2. The method for producing a diffusion layer for a fuel cell according to claim 1, wherein the concentration distribution of the water repellent in the porous substrate increases from one surface of the porous substrate to the other surface. A method for producing a diffusion layer for a fuel cell, which is controlled as described above. 請求項１又は２記載の燃料電池用拡散層の製造方法であって、前記多孔質基材の乾燥温度、前記多孔質基材に供給する風量、前記多孔質基材を乾燥する熱源と前記多孔質基材との距離のうち少なくともいずれか１つの乾燥条件が異なることを特徴とする燃料電池用拡散層の製造方法。   The method for producing a diffusion layer for a fuel cell according to claim 1 or 2, wherein a drying temperature of the porous substrate, an air volume supplied to the porous substrate, a heat source for drying the porous substrate, and the porous A method for producing a diffusion layer for a fuel cell, wherein at least any one of the drying conditions among the distances from the porous substrate is different. 多孔質基材に撥水剤を塗布する塗布工程及び前記撥水剤を塗布した多孔質基材を乾燥する乾燥工程を有する燃料電池用拡散層の製造工程と、膜−電極アッセンブリの両側に前記燃料電池用拡散層の製造工程において製造された燃料電池用拡散層を配置し、前記燃料電池用拡散層の両外側に燃料電池用セパレータを配置する配置工程とを含む燃料電池の製造方法であって、
前記乾燥工程において、前記多孔質基材の一方の面と他方の面とで異なる乾燥条件を設定し、前記多孔質基材内の撥水剤の濃度分布を制御することを特徴とする燃料電池の製造方法。 A step of applying a water repellent to a porous substrate and a step of producing a diffusion layer for a fuel cell comprising a drying step of drying the porous substrate coated with the water repellent; and on both sides of the membrane-electrode assembly, A fuel cell manufacturing method including a fuel cell diffusion layer manufactured in the fuel cell diffusion layer manufacturing process, and a fuel cell separator disposed on both outer sides of the fuel cell diffusion layer. And
In the drying step, a different drying condition is set for one surface and the other surface of the porous base material, and the concentration distribution of the water repellent in the porous base material is controlled. Manufacturing method. 請求項４記載の燃料電池の製造方法であって、前記多孔質基材内の撥水剤の濃度分布は、前記多孔質基材の膜−電極アッセンブリ側から燃料電池用セパレータ側に向かって高くなるように制御されることを特徴とする燃料電池の製造方法。   5. The method of manufacturing a fuel cell according to claim 4, wherein the concentration distribution of the water repellent in the porous substrate is higher from the membrane-electrode assembly side of the porous substrate toward the fuel cell separator side. It is controlled so that it may become. The manufacturing method of the fuel cell characterized by the above-mentioned. 請求項４又は５記載の燃料電池の製造方法であって、前記多孔質基材の乾燥温度、前記多孔質基材に供給する風量、前記多孔質基材を乾燥する熱源と前記多孔質基材との距離のうち少なくともいずれか１つの乾燥条件が異なることを特徴とする燃料電池の製造方法。   6. The method for producing a fuel cell according to claim 4, wherein a drying temperature of the porous substrate, an air volume supplied to the porous substrate, a heat source for drying the porous substrate, and the porous substrate. A method for producing a fuel cell, wherein at least one of the drying conditions is different.
JP2007145066A 2007-05-31 2007-05-31 Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell Pending JP2008300195A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2007145066A JP2008300195A (en) 2007-05-31 2007-05-31 Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2007145066A JP2008300195A (en) 2007-05-31 2007-05-31 Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell

Publications (1)

Publication Number Publication Date
JP2008300195A true JP2008300195A (en) 2008-12-11

Family

ID=40173518

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2007145066A Pending JP2008300195A (en) 2007-05-31 2007-05-31 Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell

Country Status (1)

Country Link
JP (1) JP2008300195A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013145640A (en) * 2012-01-13 2013-07-25 Toyota Motor Corp Manufacturing method of diffusion layer for fuel cell and diffusion layer for fuel cell
JP2013171775A (en) * 2012-02-22 2013-09-02 Toyota Motor Corp Fuel cell, gas diffusion layer, and method for manufacturing gas diffusion layer
JP2014232691A (en) * 2013-05-30 2014-12-11 独立行政法人産業技術総合研究所 Gas diffusion body for fuel cell, and manufacturing method thereof
JP2016178094A (en) * 2014-10-17 2016-10-06 東レ株式会社 Carbon sheet, gas diffusion electrode base material and fuel cell
WO2017110692A1 (en) * 2015-12-24 2017-06-29 東レ株式会社 Gas diffusion electrode and fuel cell
US10790516B2 (en) 2015-12-24 2020-09-29 Toray Industries, Inc. Gas diffusion electrode and method for manufacturing same
US10818934B2 (en) 2015-12-24 2020-10-27 Toray Industries, Inc. Gas diffusion electrode

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013145640A (en) * 2012-01-13 2013-07-25 Toyota Motor Corp Manufacturing method of diffusion layer for fuel cell and diffusion layer for fuel cell
JP2013171775A (en) * 2012-02-22 2013-09-02 Toyota Motor Corp Fuel cell, gas diffusion layer, and method for manufacturing gas diffusion layer
JP2014232691A (en) * 2013-05-30 2014-12-11 独立行政法人産業技術総合研究所 Gas diffusion body for fuel cell, and manufacturing method thereof
JP2016178094A (en) * 2014-10-17 2016-10-06 東レ株式会社 Carbon sheet, gas diffusion electrode base material and fuel cell
WO2017110692A1 (en) * 2015-12-24 2017-06-29 東レ株式会社 Gas diffusion electrode and fuel cell
JPWO2017110692A1 (en) * 2015-12-24 2018-10-11 東レ株式会社 Gas diffusion electrode and fuel cell
US10790516B2 (en) 2015-12-24 2020-09-29 Toray Industries, Inc. Gas diffusion electrode and method for manufacturing same
US10818934B2 (en) 2015-12-24 2020-10-27 Toray Industries, Inc. Gas diffusion electrode
US10950868B2 (en) 2015-12-24 2021-03-16 Toray Industries, Inc. Gas diffusion electrode and fuel cell

Similar Documents

Publication Publication Date Title
Omrani et al. Gas diffusion layer modifications and treatments for improving the performance of proton exchange membrane fuel cells and electrolysers: a review
JP2008300195A (en) Manufacturing method of diffusion layer for fuel cell, and manufacturing method of fuel cell
JP6381528B2 (en) Microporous layer with hydrophilic additive
Koh et al. Fabrication of highly effective self-humidifying membrane electrode assembly for proton exchange membrane fuel cells via electrostatic spray deposition
KR101728206B1 (en) Separator for fuel cell and fuel cell comprising the same
KR100599805B1 (en) Membrane/electrode assembly for fuel cell and fuel cell system comprising same
JP6192038B2 (en) Gas diffuser for fuel cell and manufacturing method thereof
JP5233075B2 (en) Catalyst layer-electrolyte membrane laminate and method for producing the same
JP7476888B2 (en) Membrane electrode assembly and polymer electrolyte fuel cell
KR20140003894A (en) Microporous layer used for fuel cell, gas diffusion layer comprising the same and fuel cell comprising the same
JP2010061966A (en) Polymer electrolyte fuel cell
JP2011096385A (en) Gas diffusion layer for cathode and method of manufacturing the same
JP2007311269A (en) Diffusion layer for fuel cell, its manufacturing method, membrane-electrode assembly for fuel cell, and fuel cell
JP2015191704A (en) Method for manufacturing membrane-electrode assembly, membrane-electrode assembly and solid polymer fuel cell having membrane-electrode assembly
JP2015050073A (en) Method for manufacturing gas diffusion layer for fuel battery
JP2007323874A (en) Conductive porous support, gas diffusion layer using this, and membrane electrode assembly with gas diffusion layer
KR101534948B1 (en) Fuelcell
JP2017117751A (en) Method for manufacturing membrane-electrode assembly, membrane-electrode assembly, and solid polymer fuel cell
JP2006031951A (en) Method of manufacturing gas diffusion electrode for solid polymer fuel cell
TWI398982B (en) Modified carbonized substrate and its manufacturing method and use
JP2008234941A (en) Manufacturing method of porous catalyst layer, manufacturing method of membrane-electrode assembly, and manufacturing method of polymer electrolyte fuel cell
JP2007299625A (en) Membrane electrode assembly and its manufacturing method
JP2007323939A (en) Fuel cell
JP2012234742A (en) Method for manufacturing fuel cell
JP2013084427A (en) Method for manufacturing membrane-catalyst layer assembly and method for manufacturing membrane electrode assembly