JPH065295A - Supporting base manufacturing for fuel cell - Google Patents

Supporting base manufacturing for fuel cell

Info

Publication number
JPH065295A
JPH065295A JP4163055A JP16305592A JPH065295A JP H065295 A JPH065295 A JP H065295A JP 4163055 A JP4163055 A JP 4163055A JP 16305592 A JP16305592 A JP 16305592A JP H065295 A JPH065295 A JP H065295A
Authority
JP
Japan
Prior art keywords
support
solid electrolyte
electrolyte layer
fuel cell
extrusion
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.)
Granted
Application number
JP4163055A
Other languages
Japanese (ja)
Other versions
JP2802196B2 (en
Inventor
Toshio Matsushima
敏雄 松島
Isao Nemoto
勲 根本
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.)
NTT Inc
Original Assignee
Nippon Telegraph and Telephone 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 Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP4163055A priority Critical patent/JP2802196B2/en
Publication of JPH065295A publication Critical patent/JPH065295A/en
Application granted granted Critical
Publication of JP2802196B2 publication Critical patent/JP2802196B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H01M8/1231—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte with both reactants being gaseous or vaporised
    • 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

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inert Electrodes (AREA)
  • Fuel Cell (AREA)

Abstract

(57)【要約】 【目的】本発明の目的は、発電セル形成部の板と他の部
分の多孔度の調整を図った中空平板状の支持体を容易か
つ経済的に作成し、よって内部抵抗の少ない高性能な固
体電解質燃料電池を実現することにある。 【構成】本発明は、空気極材料によって中空平板状の支
持体を作製し、この支持体の片側の薄板上に固体電解質
層を形成し、さらにこの固体電解質層に重ねて支持体材
料と異なる他の電極を形成し、前記支持体の固体電解質
層を形成しない面にインタコネクタ層を形成した単位発
電セルを基本発電単位として構成される固体電解質燃料
電池において、支持体を構成する固体電解質層を形成す
る平板状の押し出し成形体３２と、支持体を構成する溝
付きの押し出し成形体３１とを物性が異なる押し出し成
形用混練物によって同時に多層押し出し成形し、その後
焼結して支持体を作製することを特徴とするものであ
る。 (57) [Abstract] [Objective] An object of the present invention is to easily and economically produce a hollow flat plate-like support in which the porosity of the plate and other parts of the power generation cell forming part is adjusted, and thus It is to realize a high-performance solid electrolyte fuel cell with low resistance. According to the present invention, a hollow flat plate-shaped support is prepared from an air electrode material, a solid electrolyte layer is formed on a thin plate on one side of the support, and the solid electrolyte layer is further stacked to be different from the support material. In a solid electrolyte fuel cell including a unit power generation cell in which another electrode is formed and an interconnector layer is formed on a surface of the support on which the solid electrolyte layer is not formed, as a basic power generation unit, a solid electrolyte layer forming a support The extrusion-molded body 32 in the form of a flat plate and the extrusion-molded body 31 with grooves forming the support are simultaneously subjected to multi-layer extrusion molding with an extrusion-molded kneaded product having different physical properties, and then sintered to produce a support. It is characterized by doing.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、固体電解質燃料電池の
発電セルを構成する燃料電池用支持体の製造方法に関す
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fuel cell support which constitutes a power generation cell of a solid oxide fuel cell.

【０００２】[0002]

【従来の技術】固体電解質燃料電池（以下、ＳＯＦＣと
略称する。）は、酸素イオンの伝導性を持った固体電解
質層の両側に空気極と燃料極を配置した構造を基本とし
ている。そして、空気極側に酸素ガスや空気を、また、
燃料極側に水素等のガスを供給することによって酸素イ
オンが固体電解質を伝導し水素ガスと反応し、この反応
に伴う電流を各電極から取り出すことで発電を行ってい
る。従って、固体電解質は酸素イオンの伝導性に優れて
るとともに、酸素や水素ガスの透過を防止することが必
要であり、緻密な膜であることを要求される。それとと
もに、固体電解質の導電率は１０００℃においても他の
構成材料に比べると小さいので、発電で得た電流を取り
出す際の電圧降下を抑えるためには、５０〜２００μｍ
程度の薄い膜とする必要がある。一方、各電極は、ガス
が固体電解質と電極の接触部に容易に到達出来るよう多
孔質とすることが要求されている。このように、固体電
解質は緻密な薄膜とする必要があり、ＳＯＦＣの基本構
造としては、この固体電解質の薄膜の両側に多孔質の各
電極を形成したものとなる。しかし、このような薄膜構
造のセルは機械的な強度が不十分であるので、実用的に
は従来例の図２に示すように多孔性で不活性物質、例え
ば、カルシア安定化ジルコニアから成る管を支持体１３
とし、この支持体１３の上に空気極３・固体電解質２・
燃料極４の薄膜を重ねて形成する方式が提案された（ウ
エスチングハウス社）。図２中、１は単位発電セル、５
は集電層、１２は酸化剤通路である。しかし、この方式
においては、発電時の電流Ｉが図に示すように電極の薄
膜中を通って隣接するセルに流れるため、この部分での
電圧降下が無視できないものとなり、十分な発電特性が
得られないという問題があった。また、円筒状の支持体
１３を使用し、このような複数の単位発電セル１を組み
合わせて発電部を構成するので、円筒の内外における空
間部の占める体積が無視できないほど大きくなり、この
結果、発電部全体の体積が大きくなるという問題があっ
た。このような電圧降下が大きい点や発電部が大きいと
いう問題点を改善するため、支持体を空気極の材料で製
造し、さらに積層した際の死容積を減少させるため、形
状を、２枚の平板の中間に複数の連結部を設けた中空状
平板とし、この表面に発電部を形成する方式が本出願人
より提案された（特願平３−１１４２６１号）。その提
案は、図３に示すような構造のセルであり、（ａ）は外
観図、（ｂ）は（ａ）におけるＢ−Ｂ´線断面図を示し
ている。この構造例の単位発電セル２０では、酸化材極
材料によって薄板状で複数の貫通口２５−１を有する中
空状の支持体２５を作製し、その表面に固体電解質２
１、燃料極２２の各層を形成し、燃料極２２の反対側の
支持体２５の表面に集電層２３を設置している。そし
て、固体電解質２１およびその上面に形成される燃料極
２２は貫通口２５−１に交差する方向に横長となる形状
として複数配列している。集電層２３は燃料極２２の反
対側に支持体２５のほぼ全面を覆うように設ける。支持
体２５は、酸化材極材料として通常されているＬａＳｒ
ＭｎＯ3を使用して作製し、固体電解質２１や燃料極２
２の各層はいずれも容射法によって、固体電解質２１の
層はＹＳＺ、また、燃料極２２はＮｉＯ＋ＹＳＺをそれ
ぞれ５０〜２００μｍで作製する。また、固体電解質２
１の層の反対側の面に設ける集電層２３も溶射によって
Ｎｉ−Ａｌ2 Ｏ3 やＬａＣｒＯ3 の層を形成する。ま
た、これらの層を設けない部分には必要によって、ガス
の透過を防止するためにアルミナ等によって緻密な表面
保護層２４を形成した。2. Description of the Related Art A solid electrolyte fuel cell (hereinafter abbreviated as SOFC) is based on a structure in which an air electrode and a fuel electrode are arranged on both sides of a solid electrolyte layer having oxygen ion conductivity. And oxygen gas and air on the air electrode side,
By supplying a gas such as hydrogen to the fuel electrode side, oxygen ions conduct through the solid electrolyte and react with hydrogen gas, and the current associated with this reaction is taken out from each electrode to generate electricity. Therefore, the solid electrolyte must have excellent conductivity of oxygen ions, and must prevent permeation of oxygen and hydrogen gas, and is required to be a dense film. At the same time, the conductivity of the solid electrolyte is smaller than that of other constituent materials even at 1000 ° C., and therefore, in order to suppress the voltage drop at the time of extracting the current obtained by power generation, 50 to 200 μm is required.
It must be a thin film. On the other hand, each electrode is required to be porous so that the gas can easily reach the contact portion between the solid electrolyte and the electrode. As described above, the solid electrolyte needs to be a dense thin film, and the basic structure of the SOFC is to form porous electrodes on both sides of the thin film of the solid electrolyte. However, since the cell having such a thin film structure has insufficient mechanical strength, a tube made of a porous and inert material such as calcia-stabilized zirconia is practically used as shown in FIG. 2 of the conventional example. The support 13
And the air electrode 3, solid electrolyte 2, and
A method of forming thin films of the fuel electrode 4 by stacking them has been proposed (Westinghouse Company). In FIG. 2, 1 is a unit power generation cell, 5
Is a current collecting layer, and 12 is an oxidant passage. However, in this method, the current I during power generation flows through the thin film of the electrode to the adjacent cell as shown in the figure, so the voltage drop at this part cannot be ignored, and sufficient power generation characteristics are obtained. There was a problem that I could not. In addition, since the cylindrical support 13 is used and the plurality of unit power generation cells 1 are combined to form the power generation section, the volume occupied by the space inside and outside the cylinder becomes so large that it cannot be ignored. There is a problem in that the volume of the entire power generation section becomes large. In order to improve such a problem that the voltage drop is large and the power generation part is large, the support is manufactured from the material of the air electrode, and the dead volume when laminated is further reduced. A method of forming a hollow flat plate having a plurality of connecting parts in the middle of the flat plate and forming a power generation part on the surface has been proposed by the present applicant (Japanese Patent Application No. 3-114261). The proposal is a cell having a structure as shown in FIG. 3, where (a) is an external view and (b) is a sectional view taken along line BB ′ in (a). In the unit power generation cell 20 of this structural example, a thin plate-shaped support 25 having a plurality of through holes 25-1 is made of an oxide electrode material, and the solid electrolyte 2 is formed on the surface thereof.
1. Each layer of the fuel electrode 22 is formed, and the current collecting layer 23 is provided on the surface of the support 25 opposite to the fuel electrode 22. The solid electrolyte 21 and the fuel electrode 22 formed on the upper surface of the solid electrolyte 21 are arranged in a laterally long shape in a direction intersecting the through hole 25-1. The current collecting layer 23 is provided on the opposite side of the fuel electrode 22 so as to cover almost the entire surface of the support 25. The support 25 is made of LaSr which is usually used as an electrode material for an oxidant.
Manufactured using MnO 3 , solid electrolyte 21 and fuel electrode 2
Each layer of No. 2 is made of YSZ for the layer of the solid electrolyte 21 and NiO + YSZ for the fuel electrode 22 with the thickness of 50 to 200 μm by the injection method. In addition, the solid electrolyte 2
The current collecting layer 23 provided on the surface opposite to the first layer also forms a layer of Ni—Al 2 O 3 or LaCrO 3 by thermal spraying. If necessary, a dense surface protective layer 24 made of alumina or the like was formed in a portion where these layers were not provided in order to prevent gas permeation.

【０００３】図３に示す提案のセルによって、ウエスチ
ングハウス社方式のＳＯＦＣに見られた問題点の大幅な
改善が図られた。しかし、この方式においても電流の横
流れの完全な解消は困難であることも原因となり、ある
程度の電圧降下による性能低下が存在している。このよ
うな点の改善法の一つとしては、この方式のＳＯＦＣに
おいては固体電解質を形成した薄板のみが電極として作
用する部分であり多孔性が必要であるが、これ以外の部
分については導電部としてのみ作用すれば良いので、緻
密な焼結体として高い導電性を与えることが考えられ
る。このような対策を施さないと中空板を使用した構成
のＳＯＦＣの発電特性が十分に発揮できないという問題
があった。なお、このように多孔性が部分的に異なる不
均一な中空板の製造法としては、従来ドクターブレード
法等のテープキャストによって、焼結後の密度が異なる
複数のグリーンシートを作製しておき、次にこれらのシ
ートをホットプレスによって加熱・加圧積層してこれを
焼結する方法が考えられる。しかし、このようなシート
の積層のためには、通常、シートの加熱温度が５０〜７
０℃、加圧力としては１００〜２００ｋｇ／cm2 が必要
である。このような積層条件で中空状の板を積層しよう
としても中空部には大きな圧力が加わり潰れてしまい、
一方、加える力が不十分であると各シートの溶着が不十
分となり焼結のプロセスで各シートの界面が剥離すると
いう問題があった。The proposed cell shown in FIG. 3 has greatly improved the problems found in the Westinghouse SOFC. However, even in this method, it is difficult to completely eliminate the lateral current flow, and there is some deterioration in performance due to a voltage drop. As one of the methods for improving such a point, in the SOFC of this method, only the thin plate on which the solid electrolyte is formed is a portion that acts as an electrode, and porosity is required. Since it suffices to act only as, it is considered that high conductivity is given as a dense sintered body. Unless such measures are taken, there is a problem that the power generation characteristics of the SOFC having a hollow plate cannot be fully exhibited. Incidentally, as a method for producing a non-uniform hollow plate having partially different porosity, a plurality of green sheets having different densities after sintering are prepared in advance by tape casting such as a doctor blade method. Next, a method is conceivable in which these sheets are hot-pressed and laminated by hot pressing and then sintered. However, in order to stack such sheets, the heating temperature of the sheets is usually 50 to 7
It is necessary to apply 0 to 0 ° C. and a pressure of 100 to 200 kg / cm 2 . Even if an attempt is made to stack hollow plates under such a stacking condition, a large pressure is applied to the hollow part, and the hollow part is crushed.
On the other hand, if the applied force is insufficient, there is a problem that the welding of each sheet is insufficient and the interface of each sheet is separated during the sintering process.

【０００４】[0004]

【発明が解決しようとする課題】本発明の目的は、中空
平板型ＳＯＦＣの支持体として使用する中空状平板の経
済的な製造方法に関わり、発電セル形成部の板と他の部
分の多孔度の調整を図った不均一中空板を容易かつ経済
的に作成し、よって内部抵抗の少ない高性能なＳＯＦＣ
を実現することにある。The object of the present invention relates to an economical method for producing a hollow flat plate used as a support for a hollow flat plate type SOFC, and relates to the porosity of the plate of the power generation cell forming part and other parts. A high-performance SOFC with low internal resistance, which can easily and economically create a non-uniform hollow plate
Is to realize.

【０００５】[0005]

【課題を解決するための手段】本発明は上記課題を解決
するために、空気極材料によって中空平板状の支持体を
作製し、この支持体の片側の薄板上に固体電解質層を形
成し、さらにこの固体電解質層に重ねて支持体材料と異
なる他の電極を形成し、前記支持体の固体電解質層を形
成しない面にインタコネクタ層を形成した単位発電セル
を基本発電単位として構成される固体電解質燃料電池に
おいて、支持体を構成する固体電解質層を形成する薄板
と、支持体を構成するその他の部分とを物性が異なる押
し出し成形用混練物によって同時に多層押し出し成形
し、その後焼結して支持体を作製することを特徴とする
ものである。又、空気極材料としてＬａＳｒＭｎＯ3 を
使用し、固体電解質層を形成する薄板は多孔性に富み、
他の部分は緻密性となるように調整された押し出し成形
用混練物によって同時に多層押し出し成形し、その後焼
結することを特徴とするものである。更に、空気極材料
としてＬａＳｒＭｎＯ3 とＬａＳｒＣｏＯ3 を使用し、
固体電解質層を形成する薄板にはＬａＳｒＭｎＯ3 、他
の部分にはＬａＳｒＣｏＯ3 を使用し、これらの押し出
し成形用混練物によって同時に多層押し出し成形し、そ
の後焼結することを特徴とするものである。In order to solve the above-mentioned problems, the present invention produces a hollow flat plate-like support from an air electrode material, and forms a solid electrolyte layer on a thin plate on one side of the support, Furthermore, another electrode different from the support material is formed on the solid electrolyte layer, and an interconnector layer is formed on the surface of the support on which the solid electrolyte layer is not formed. In an electrolyte fuel cell, a thin plate that forms a solid electrolyte layer that constitutes a support and other parts that constitute a support are simultaneously extrusion-molded in multiple layers by a kneading product for extrusion molding having different physical properties, and then sintered and supported. It is characterized by making a body. Also, LaSrMnO 3 is used as the air electrode material, and the thin plate forming the solid electrolyte layer is rich in porosity,
The other part is characterized in that it is simultaneously subjected to multilayer extrusion molding with an extrusion-molded kneaded material adjusted to have a high density and then sintered. Furthermore, using LaSrMnO 3 and LaSrCoO 3 as air electrode materials,
The thin LaSrMnO 3 to form a solid electrolyte layer, the other part using the LaSrCoO 3, and a multilayer extruded simultaneously by these extrusion molding the kneaded product, and is characterized in that subsequent sintering.

【０００６】[0006]

【作用】本発明は、どちらか一方の電極材料によって、
２枚の平板の間に複数の連結部を設け、内部に一端から
これに相対する他の面に向けて貫通口を有する中空状の
支持体を形成し、該支持体の片面に電解質層を配置し該
電解質層の上面に他の電極を形成するＳＯＦＣにおける
中空状の支持体の製造方法に関わり、前記支持体が、固
体電解質を形成する薄板は多孔体で、他の部分は緻密体
となるように調整された押し出し成形用混練物によって
同時に多層押し出し成形し、その後焼結することを特徴
としている。本発明によれば、ドクターブレード法等の
テープキャストによりグリーンシートの作製や積層とい
ったプロセスを経ることなく、押し出し成形用混練物の
調整と多層押し出しの操作のみによって部分的に多孔性
の異なる中空平板状の支持体を作製することが出来る。According to the present invention, either one of the electrode materials can be used
A plurality of connecting portions are provided between two flat plates, and a hollow support having a through hole from one end to the other surface facing the same is formed inside, and an electrolyte layer is formed on one surface of the support. The present invention relates to a method for manufacturing a hollow support in SOFC in which another electrode is arranged and the other electrode is formed on the upper surface of the electrolyte layer, wherein the support is a porous thin plate forming the solid electrolyte, and the other part is a dense body. It is characterized in that a multi-layer extrusion molding is simultaneously performed by an extrusion-molded kneaded material which is adjusted so that it is then sintered. According to the present invention, a hollow flat plate having partially different porosity only by adjusting the kneaded material for extrusion molding and the operation of multi-layer extrusion without going through processes such as production and lamination of green sheets by tape casting such as doctor blade method. It is possible to prepare a support in the shape of a circle.

【０００７】[0007]

【実施例】図１に、本発明の実施例の製造概念を示す。
このうち、（ａ）は溝付きの押し出し成形体３１と平板
状の押し出し成形体３２の多層押し出しによる実施例で
あり、（ｂ）は平板状の押し出し成形体３２−２上に角
柱状の押し出し成形体３３を重ね、さらにその上に平板
状の押し出し成形体３２−１を重ねた実施例である。具
体的には多層押し出し成形機で成形が開始されると
（ａ）においては、まず、溝付きの押し出し成形体３１
が押し出され、その後若干遅れて平板状の押し出し成形
体３２の押し出しが開始され、溝付きの押し出し成形体
３１に重ねることで中空平板状の支持体が形成される。
（ｂ）についても同様に、まず下に位置する平板状の押
し出し成形体３２−２が押し出され、少し遅れて角柱状
の押し出し成形体３３が、そして最後にこれに重なるよ
うに平板状の押し出し成形体３２−１が押し出され、こ
れらによって中空平板状の支持体が形成される。以下、
具体的に述べる。EXAMPLE FIG. 1 shows a manufacturing concept of an example of the present invention.
Among these, (a) is an embodiment by multilayer extrusion of a grooved extrusion molded body 31 and a flat plate-shaped extrusion molded body 32, and (b) is a prismatic extrusion on a flat plate-shaped extrusion molded body 32-2. This is an example in which the molded body 33 is stacked, and the flat plate-shaped extrusion molded body 32-1 is further stacked thereon. Specifically, when molding is started by a multilayer extrusion molding machine, in (a), first, an extrusion molded body 31 with a groove is formed.
Is extruded, and after that, extrusion of the flat plate-shaped extruded body 32 is started with a slight delay, and the hollow extruded body 31 is superposed to form a hollow flat plate-shaped support body.
Similarly for (b), first, the flat plate-shaped extruded body 32-2 located below is extruded, the prismatic extruded body 33 is slightly delayed, and finally the flat plate-shaped extruded body 33 is superposed thereon. The molded body 32-1 is extruded to form a hollow flat plate-shaped support body. Less than,
Specifically,

【０００８】まず、ＬａＳｒＭｎＯ3 材料によって本発
明の中空平板状の支持体を形成した例について示す。即
ち、ＬａＳｒＭｎＯ3 としては、ここでは一般的に使用
されている（Ｌａ1-x Ｓｒx ）1-Y ＭｎＯ3 （０≦Ｘ≦
０．６、 ０≦Ｙ≦０．２）の範囲のものを使用した。
なお、粒径としては１μｍ〜１０μｍのものである。こ
のような材料に、セルロース系のバインダを水とともに
添加しこれを混練機によって混練し、押し出し用の材料
を調整した。これを試料１００に対して３〜５の比で添
加し、さらにグリセリンを２〜５の比で加え、これに水
を１０〜１５加えて混練した。なお、中空平板状の支持
体を用いるＳＯＦＣにおいては、片面は発電部を形成す
るものであり、この部分では中空部内を流れる酸素ガス
の拡散が必要であり、多孔性が要求される。一方、他の
部分では電流の通過によって生じる電圧降下を抑制する
ために高い電子伝導性が要求され、緻密な焼結体である
ことが望ましい。このような物性を得るため、多孔性が
求められる部分には混練した材料中に揮発性の物質を混
入させたり、粒径の大きい粉末を使用し、一方、緻密な
焼結体が要求される部分には焼結性を高めるため粒径の
小さい粉末を用いたり、粒径の小さい粉末だけで焼結時
の収縮が大きすぎる場合には、この粉末に粒径の異なる
粉末を混合して使用した。図１（ａ）においては、溝付
きの押し出し成形体３１には緻密化し易い押し出し材料
を使用し、電解質と他の電極を形成する平板状の押し出
し成形体３２には多孔性が得られる押し出し材料を適用
して多層押し出し成形を行っている。また、図１（ｂ）
においては、２つの平板状の押し出し成形体３２−１と
３２−２のうち、どちらか一方の平板状の押し出し成形
体に多孔性が得られる材料を、また、他の部分には緻密
体が得られる材料を適用した。このように、成形した多
層押し出し体を焼結することによって、片側が多孔性で
他の面および中間に位置する角柱状の押し出し成形体が
緻密な中空平板状の支持体を得た。ＬａＳｒＭｎＯ3 の
導電率は、焼結体の密度によって変わり、密度が高いほ
うが導電率も高い。ちなみに、今回調整した押し出し成
形体の焼結体の導電率は、以下の通りである。First, an example in which the hollow flat plate-shaped support of the present invention is formed of a LaSrMnO 3 material will be described. That is, as LaSrMnO 3 , (La 1-x Sr x ) 1-Y MnO 3 (0 ≦ X ≦) which is generally used here is used.
0.6, 0 ≦ Y ≦ 0.2) was used.
The particle size is 1 μm to 10 μm. A cellulose-based binder was added to such a material together with water, and this was kneaded by a kneader to prepare a material for extrusion. This was added to the sample 100 in a ratio of 3 to 5, glycerin was added in a ratio of 2 to 5, and water was added to this in an amount of 10 to 15 and kneaded. In an SOFC using a hollow flat plate-shaped support, one surface forms a power generation section, and oxygen gas flowing in the hollow section needs to be diffused in this section, and porosity is required. On the other hand, in other portions, high electron conductivity is required to suppress the voltage drop caused by the passage of current, and it is desirable that the sintered body be dense. In order to obtain such physical properties, a volatile substance is mixed into the kneaded material or a powder having a large particle size is used in a portion where porosity is required, while a dense sintered body is required. Use powder with a small particle size to improve sinterability, or if powder with a small particle size causes too large shrinkage during sintering, mix powder with different particle size and use. did. In FIG. 1A, an extruded material that is easy to densify is used for the grooved extruded body 31, and a porous extruded material is used for the flat plate-shaped extruded body 32 that forms the electrolyte and other electrodes. Is applied to perform multi-layer extrusion molding. In addition, FIG.
In the above, in one of the two flat plate-shaped extruded bodies 32-1 and 32-2, one of the flat plate-shaped extruded bodies is made of a material having porosity, and in the other part, a dense body is used. The resulting material was applied. In this way, by sintering the formed multi-layered extruded body, a hollow flat plate-shaped support body was obtained in which one side was porous and the prismatic extruded body positioned on the other surface and in the middle was dense. The conductivity of LaSrMnO 3 changes depending on the density of the sintered body, and the higher the density, the higher the conductivity. By the way, the conductivity of the sintered compact of the extruded body adjusted this time is as follows.

【０００９】[0009]

【表１】 次に、ＬａＳｒＭｎＯ3 とＬａＳｒＣｏＯ3 を空気極材
料に使用した例について述べる。ＬａＳｒＭｎＯ3 とし
ては、ここでも（Ｌａ1-x Ｓｒx ）1-Y ＭｎＯ3 （０≦
Ｘ≦０．６、 ０≦Ｙ≦０．２）の範囲のものを使用し
た。また、ＬａＳｒＣｏＯ3 については（Ｌａ1-x Ｓｒ
x ）ＣｏＯ3 （０≦Ｘ≦０．８）を使用した。この例で
は、発電部を形成し多孔性が要求される薄板には（Ｌａ
1-x Ｓｒx ）1-Y ＭｎＯ3 を、一方、これ以外の部分に
は電子伝導性が高い（Ｌａ1-x Ｓｒx ）ＣｏＯ3 （０≦
Ｘ≦０．８）を使用した。また、粒径としては１μｍ〜
１０μｍのものを用い、このような材料に、先に述べた
ものと同一のセルロース系のバインダと水を添加しこれ
を混練機によって混練し、押し出し用の材料を調整し
た。ＬａＳｒＭｎＯ3 とＬａＳｒＣｏＯ3 の導電率は、
焼結密度によって若干変わるが、その値をおおよそ示す
と以下の通りである。[Table 1] Next, an example in which LaSrMnO 3 and LaSrCoO 3 are used as the air electrode material will be described. As LaSrMnO 3 , here also (La 1-x Sr x ) 1-Y MnO 3 (0 ≦
X ≦ 0.6, 0 ≦ Y ≦ 0.2) were used. For LaSrCoO 3 , (La 1-x Sr
x ) CoO 3 (0 ≦ X ≦ 0.8) was used. In this example, the thin plate that forms the power generation part and requires porosity is (La
1-x Sr x ) 1-Y MnO 3 and, on the other hand, (La 1-x Sr x ) CoO 3 (0≤
X ≦ 0.8) was used. The particle size is 1 μm
A material for extrusion was prepared by using a material having a thickness of 10 μm and adding the same cellulose-based binder and water as those described above to the material and kneading the material with a kneader. The conductivity of LaSrMnO 3 and LaSrCoO 3 is
Although it varies slightly depending on the sintered density, the value is roughly shown below.

【００１０】[0010]

【表２】 従って、電極部以外の部分をＬａＳｒＣｏＯ3 にするこ
とで中空板の電圧降下による損失を、ＬａＳｒＭｎＯ3
材による均一板に較べ３０％程度減少させることが出来
る。[Table 2] Thus, losses due to voltage drop of the hollow plate by the portions other than the electrode portion LaSrCoO 3, LaSrMnO 3
It can be reduced by about 30% compared to a uniform plate made of wood.

【００１１】そして、このような中空平板状の支持体に
電解質と燃料極の層を形成して単位発電セルを作製し
た。電解質と燃料極の形成には溶射法を適用し、まず、
イットリア安定化ジルコニア（イットリア含有量は８モ
ル％）から成る電解質薄膜を形成した。次に、この膜上
にニッケルジルコニアサーメットによって燃料極を形成
した。なお、これら各層の厚みはいずれも５０〜２００
μｍとした。そして、電解質を形成した面の反対側にラ
ンタンクロマイトを用いて集電層を溶射した。また、こ
れらの薄膜を形成させた部分以外には、空気極材料が還
元雰囲気にさらされ分解してしまうことを防ぐため、ア
ルミナによって緻密な表面保護層を形成した。Then, layers of the electrolyte and the fuel electrode were formed on such a hollow flat plate-like support to prepare a unit power generation cell. Applying the thermal spraying method to the formation of electrolyte and fuel electrode,
An electrolyte thin film composed of yttria-stabilized zirconia (yttria content: 8 mol%) was formed. Next, a fuel electrode was formed on this film by nickel zirconia cermet. The thickness of each of these layers is 50 to 200.
μm. Then, a lanthanum chromite was used to spray a current collecting layer on the side opposite to the surface on which the electrolyte was formed. In addition, in order to prevent the air electrode material from being decomposed by being exposed to a reducing atmosphere, a dense surface protective layer was formed by using alumina except the portions where these thin films were formed.

【００１２】本発明のＳＯＦＣの動作にあたっては、従
来のＳＯＦＣと同様、本発電ブロックを１０００℃等の
温度条件下に設置し、各ガスを供給するだけである。単
位発電セルにおけるガスの供給方法としては、支持体の
内側に酸化剤ガスを、そして、外側に水素ガスを供給す
る。この単位発電セルによって、発電モジュールが構成
され、この発電モジュールにおいてガスが供給される。In operation of the SOFC of the present invention, like the conventional SOFC, the present power generation block is installed under a temperature condition such as 1000 ° C. and each gas is supplied. As a gas supply method in the unit power generation cell, an oxidant gas is supplied inside the support and a hydrogen gas is supplied outside. A power generation module is configured by this unit power generation cell, and gas is supplied in this power generation module.

【００１３】従来の円筒型支持体を使用するＳＯＦＣで
は、多孔質チューブ上に固体電解質薄膜、各電極等を積
層していた。このような円筒型では次のような問題点が
あった。（１）発電電流が電極内を面に沿って流れ電流
の通路が長くなるため、内部抵抗が大きくなる。（２）
支持体が円筒であるためにこれらを複数接続した場合発
電部が大きくなり、出力密度にも限界が生じる。In a conventional SOFC using a cylindrical support, a solid electrolyte thin film, electrodes, etc. are laminated on a porous tube. Such a cylindrical type has the following problems. (1) Since the generated current flows along the surface in the electrode and the path of the current is long, the internal resistance becomes large. (2)
Since the support is a cylinder, if a plurality of these are connected, the power generation section becomes large and the output density is limited.

【００１４】このような欠点を解決するために本発明で
は電極材料によって支持体を作製し、かつ、支持体の形
状を中空平板状としている。この結果、電流は電極に対
し垂直に流れるようになり、従来の円筒型で見られたよ
うな電流の電極内の横方向の流れを防止することがで
き、放電特性の改善と発電部の小型化が達成された。従
来、このような中空平板状の支持体を作製するために
は、ドクターブレード法等でテープキャストを行い、こ
れを積層して焼結させる手段や押し出し成形法が採られ
ていた。しかし、前者の方法では作製プロセスが複雑で
あり、後者の方法では特性の改善に効果を持つ部分的に
多孔性が異なる支持板の作製は行えなかった。本発明
は、ＳＯＦＣの支持体に適した、多孔度や組成が部分的
に異なる不均一中空板の簡易な作製法として、多層押し
出しを行うものであり、これによって優れた性能を有す
るＳＯＦＣを経済的に作製することができる。In order to solve such a drawback, in the present invention, a support is made of an electrode material, and the support has a hollow flat plate shape. As a result, the current flows perpendicularly to the electrodes, which prevents the current from flowing in the electrodes in the lateral direction as seen in the conventional cylindrical type, improving the discharge characteristics and reducing the size of the power generation unit. Has been achieved. Conventionally, in order to manufacture such a hollow flat plate-shaped support, a means for performing tape casting by a doctor blade method or the like, laminating and sintering this, and an extrusion molding method have been adopted. However, the former method is complicated in the production process, and the latter method cannot produce a support plate having partially different porosity which is effective in improving the characteristics. INDUSTRIAL APPLICABILITY The present invention is to perform multi-layer extrusion as a simple method for producing a heterogeneous hollow plate having a partially different porosity and composition, which is suitable for a SOFC support. Can be manufactured in a simple manner.

【００１５】[0015]

【発明の効果】以上説明したように、従来の性能を凌ぐ
ＳＯＦＣを構成するには、支持体を中空平板状とするこ
とが有効である。しかし、この支持体の性能をさらに向
上させないと、中空平板状の支持体を使用した際の性能
が十分に引き出せないという問題があった。そこで、本
発明では、中空平板状支持体には電極として作用する部
分と単なる導電体として作用する部分の２つの部分があ
ることに着目し、この目的に叶った、多孔性や組成が部
分に応じて異なる不均一な中空平板状支持体を簡易に作
製することを目的に、多層押し出し法を適用するもので
ある。As described above, in order to construct an SOFC that surpasses the conventional performance, it is effective to form the support into a hollow flat plate. However, there is a problem in that the performance when using a hollow flat plate-shaped support cannot be sufficiently obtained unless the performance of the support is further improved. Therefore, in the present invention, attention is paid to the fact that the hollow flat plate-shaped support has two parts, a part that acts as an electrode and a part that acts simply as a conductor, and the porosity and the composition that meet this purpose are included in the part. The multi-layer extrusion method is applied for the purpose of easily producing different inhomogeneous hollow flat plate supports.

【００１６】これまで、従来の円筒型では、内部抵抗が
大きいことと、空間部が多く出力密度の向上が図りがた
いという欠点があった。このような課題を解消するに
は、支持体の形状を中空平板状とし材料には電極材を使
用するセル構成が有効であった。しかし、この方式にお
いても、電極として作用する部分は電解質膜を作製した
片側の薄板だけであり、他の部分は単なる導電部となっ
ていた。このような中空平板状支持体を全て同一の多孔
性で作製すると、導電部においても電極部と同一の導電
率しか得られずセルを形成した際の十分な性能が引き出
せないという欠点があった。この解決のためには、電極
として作用する部分と導電に関わる部分に応じて多孔性
を変えた不均一な中空板や、導電部として作用する部分
の組成を変えた不均一な中空板が望ましい。しかし、こ
のような不均一な中空板の作製法としては従来、ドクタ
ーブレード法等のテープキャストシートの熱加圧積層に
よることが考えられるが、この積層法では中空部が潰れ
てしまい、目的とする支持体の作製が出来なかった。本
発明では、このような不均一な中空板を、各部の多孔性
や組成に応じた押し出し用混練体の作製とこの混練体の
多層押し出しという簡易なプロセスで作製可能としてい
る。本発明によって、電極材からなる不均一な中空平板
状支持体が効率良く作製され、この結果、本方式のＳＯ
ＦＣセルの性能を最大限に引き出すことが可能となる。Up to now, the conventional cylindrical type has the drawbacks that it has a large internal resistance and that it is difficult to improve the output density because there are many spaces. In order to solve such a problem, a cell configuration in which the support has a hollow flat plate shape and an electrode material is used as a material has been effective. However, also in this method, the portion acting as the electrode is only the thin plate on one side where the electrolyte membrane is formed, and the other portions are merely conductive portions. If all such hollow flat plate-shaped supports were made to have the same porosity, there was a drawback in that even in the conductive part, only the same conductivity as that of the electrode part was obtained, and sufficient performance at the time of forming cells could not be obtained. . In order to solve this problem, it is desirable to use a non-uniform hollow plate whose porosity is changed depending on the part acting as an electrode and the part related to conductivity, or a non-uniform hollow plate in which the composition of the part acting as a conductive part is changed. . However, as a method for producing such a non-uniform hollow plate, conventionally, it has been considered that a hot pressing lamination of tape cast sheets such as a doctor blade method, but this lamination method crushes the hollow part, It was not possible to produce a support that does. In the present invention, such a non-uniform hollow plate can be produced by a simple process of producing a kneading body for extrusion according to the porosity and composition of each part and multi-layer extrusion of this kneading body. According to the present invention, a non-uniform hollow flat plate-shaped support made of an electrode material is efficiently produced. As a result, the SO
It is possible to maximize the performance of the FC cell.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明に係る中空平板状支持体の一例を示す分
解斜視図である。FIG. 1 is an exploded perspective view showing an example of a hollow flat plate-shaped support according to the present invention.

【図２】従来の円筒型燃料電池を示す斜視図である。FIG. 2 is a perspective view showing a conventional cylindrical fuel cell.

【図３】従来の中空平板状支持体を用いた単位発電セル
を示す外観斜視図および断面図である。FIG. 3 is an external perspective view and a cross-sectional view showing a unit power generation cell using a conventional hollow flat plate-shaped support.

【符号の説明】[Explanation of symbols]

１…単位発電セル、 ２…固体電解質、 ３…
空気極、４…燃料極、 ５…集電層、
１２…酸化剤通路、１３…支持体、 ２０
…単位発電セル、 ２１…固体電解質、２２…燃料極、
２３…集電層、 ２４…表面保護層、
２５…支持体、 ２５−１…貫通口、３１…溝
付きの押し出し成形体、３２…平板状の押し出し成形
体、３３…角柱状の押し出し成形体。1 ... Unit power generation cell, 2 ... Solid electrolyte, 3 ...
Air electrode, 4 ... Fuel electrode, 5 ... Current collecting layer,
12 ... Oxidant channel, 13 ... Support, 20
... Unit power generation cell, 21 ... Solid electrolyte, 22 ... Fuel electrode,
23 ... Current collecting layer, 24 ... Surface protective layer,
Reference numeral 25 ... Support, 25-1 ... Through hole, 31 ... Groove extrusion molding, 32 ... Flat plate extrusion molding, 33 ... Square prism extrusion molding.

Claims (3)

【特許請求の範囲】[Claims] 【請求項１】 空気極材料によって中空平板状の支持体
を作製し、この支持体の片側の薄板上に固体電解質層を
形成し、さらにこの固体電解質層に重ねて支持体材料と
異なる他の電極を形成し、前記支持体の固体電解質層を
形成しない面にインタコネクタ層を形成した単位発電セ
ルを基本発電単位として構成される固体電解質燃料電池
において、支持体を構成する固体電解質層を形成する薄
板と、支持体を構成するその他の部分とを物性が異なる
押し出し成形用混練物によって同時に多層押し出し成形
し、その後焼結して支持体を作製することを特徴とする
燃料電池用支持体の製造方法。1. A hollow flat plate-shaped support is made of an air electrode material, a solid electrolyte layer is formed on a thin plate on one side of the support, and another solid electrolyte layer is formed on the solid electrolyte layer to form another solid electrolyte layer. In a solid electrolyte fuel cell including a unit power generation cell in which an electrode is formed and an interconnector layer is formed on a surface of the support on which the solid electrolyte layer is not formed, a solid electrolyte layer forming a support is formed. A thin plate to be formed, and other portions constituting the support are simultaneously multi-layered by extrusion kneading products with different physical properties, and then sintered to produce a support, which is characterized in that the support for a fuel cell is manufactured. Production method. 【請求項２】 請求項１記載の燃料電池用支持体の製造
法において、空気極材料としてＬａＳｒＭｎＯ3 を使用
し、固体電解質層を形成する薄板は多孔性に富み、他の
部分は緻密性となるように調整された押し出し成形用混
練物によって同時に多層押し出し成形し、その後焼結す
ることを特徴とする燃料電池用支持体の製造方法。2. The method for producing a fuel cell support according to claim 1, wherein LaSrMnO 3 is used as an air electrode material, the thin plate forming the solid electrolyte layer is rich in porosity, and the other part is dense. A method for producing a support for a fuel cell, which comprises simultaneously performing multi-layer extrusion molding with an extrusion-molded kneaded material that is adjusted so that it is then sintered. 【請求項３】 請求項１記載の燃料電池用支持体の製造
法において、空気極材料としてＬａＳｒＭｎＯ3 とＬａ
ＳｒＣｏＯ3 を使用し、固体電解質層を形成する薄板に
はＬａＳｒＭｎＯ3 、他の部分にはＬａＳｒＣｏＯ3 を
使用し、これらの押し出し成形用混練物によって同時に
多層押し出し成形し、その後焼結することを特徴とする
燃料電池用支持体の製造方法。3. The method for manufacturing a fuel cell support according to claim 1, wherein LaSrMnO 3 and La are used as air electrode materials.
Using the SrCoO 3, characterized in that the thin plate LaSrMnO 3 to form a solid electrolyte layer, which is the other portion using the LaSrCoO 3, and a multilayer extruded simultaneously by these extrusion molding the kneaded product, and then sintered And a method for manufacturing a fuel cell support.
JP4163055A 1992-06-22 1992-06-22 Method for producing fuel cell support Expired - Lifetime JP2802196B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4163055A JP2802196B2 (en) 1992-06-22 1992-06-22 Method for producing fuel cell support

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4163055A JP2802196B2 (en) 1992-06-22 1992-06-22 Method for producing fuel cell support

Publications (2)

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JPH065295A true JPH065295A (en) 1994-01-14
JP2802196B2 JP2802196B2 (en) 1998-09-24

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011077923A1 (en) * 2009-12-24 2011-06-30 日本碍子株式会社 Method for producing solid oxide fuel cell and method for producing divided solid oxide fuel cell molded product
WO2014027442A1 (en) * 2012-08-13 2014-02-20 株式会社リケン Fuel electrode which also serves as supporting body of solid oxide fuel cell, and fuel electrode-supported solid oxide fuel cell

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011077923A1 (en) * 2009-12-24 2011-06-30 日本碍子株式会社 Method for producing solid oxide fuel cell and method for producing divided solid oxide fuel cell molded product
US8999607B2 (en) 2009-12-24 2015-04-07 Ngk Insulators, Ltd. Manufacturing method of solid oxide fuel cell, and manufacturing method of compact of divided member of the cell
WO2014027442A1 (en) * 2012-08-13 2014-02-20 株式会社リケン Fuel electrode which also serves as supporting body of solid oxide fuel cell, and fuel electrode-supported solid oxide fuel cell
JP5458222B1 (en) * 2012-08-13 2014-04-02 株式会社リケン A fuel electrode serving as a support for a solid oxide fuel cell and a solid oxide fuel cell supporting the fuel electrode

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