JP2004063460A - Solid-state electrolyte fuel cell and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state electrolyte fuel cell and its method, capable of obtaining a cell output even at a low temperature less than 500°C and using a material easy to process with low cost as a separator, a housing material, etc., in a solid-state electrolyte fuel cell. <P>SOLUTION: The cell is composed of an oxide proton conductor with composition expressed in Ba (Zr<SB>1-x</SB>Ce<SB>x</SB>)<SB>1-y</SB>M<SB>y</SB>Al<SB>z</SB>O<SB>3-α</SB>(M: a trivalent. rare-earth element, 1≥x≥0, 0.3>y>0, 0.04>z≫0, 1.5>1>0) and an electrode with a catalyst performance dominantly composed of platinum. An electrolyte has a film structure with a not more than 300 μm thick. <P>COPYRIGHT: (C)2004,JPO

Description

この表１から明らかなように、室温付近でも、加湿することなく発電する電解質材料が確認された。酸化物プロトン伝導体として、このような温度で発電が確認されたのは従来にない技術と考えられる。
【００４６】
本発明によれば、室温付近でプロトン伝導が確認される電解質材料と、薄膜化技術とにより、室温付近で発電可能な固体電解質型燃料電池が提供できる。勿論、室温以上の温度でも、例えば、３００℃でも５００℃でも発電ができることは図２、表１から明らかである。
【００４７】
（実施例２）
酸化物プロトン伝導体では、電解質の厚さを薄くすればするほど、電池内部抵抗を低減でき、電池の出力特性を向上させることができる。
【００４８】
しかしながら、機械加工、研磨による薄膜化は、材料の機械強度に依存するところが大きい。従来のプロトン伝導体材料では、４５０μｍから５００μｍの厚さが限度であったが、一般に、電解質単独で３００μｍ以下にできる材料であるかどうかが実用上の一つの目安となる。すなわち、本発明では、固体電解質は、３００μｍ以下の膜構造であることが好ましい。
【００４９】
そこで、上述の実施例１の表１で示した複数のプロトン伝導体材料である電解質材料の機械的強度を、次のようにして評価した。
【００５０】
すなわち、上述の実施例１で用いた焼結体法により得られた電解質材料を試料とし、機械的研磨により薄膜化したもので、図３に示されるように、直径１３ｍｍの円盤状の試料１を研磨し、この試料１の両側を１０ｍｍの間隔で支持し、中央の直径部分に１ｋｇ重の重さをかけて抗折強度を評価したものである。
【００５１】
下記の表２に、前記１ｋｇ重に耐え得る限界の膜厚を示している。
【００５２】
【表２】

この表２に示されるように、固体電解質単独で、膜厚１００μｍまで強度を保つものも存在するが、ほとんどのものは、膜厚３００μｍ程度までは機械研磨により薄膜化が可能であることが確認された。
【００５３】
本実施例では、機械的強度が充分でないものに対して、樹脂で機械的強度の補強を行ったものである。
【００５４】
本実施例では、上記と同様に、焼結体電解質を切り出し、研磨により薄膜化する。薄膜化した固体電解質膜２の周囲に、図４に示すように、支持構造体としてエポキシ樹脂枠３で補強を行った。
【００５５】
このエポキシ樹脂枠３は、厚さが１ｍｍであって、９ｍｍ×９ｍｍの矩形の中央部に、３ｍ×３ｍｍの開口を有する形状である。このエポキシ樹脂枠３の中央部に、５ｍｍ×５ｍｍの矩形の固体電解質膜２の周縁部が保持されたものであって、固体電解質膜２の上面および下面が、エポキシ樹脂枠３の前記開口から臨むように構成されている。また、この例では、固体電解質膜２は、エポキシ樹脂枠３の厚み方向のほぼ中央位置に保持されている。
【００５６】
かかるエポキシ樹脂枠３を有する試料４を、上記と同様の試験、すなわち、矩形のエポキシ樹脂枠３の対角線を中心にして、左右５ｍｍ離した位置に支持台を配置し、前記対角線に沿って１ｋｇ重の重さを前記エポキシ樹脂枠３にかけることによって行った。
【００５７】
この抗折強度試験で強度を調べたところ、表２に示す材料の全てで、１ｋｇ重の重さに耐え得ることが可能であることが確認された。また、いずれの試料においても、５ｍｍ×５ｍｍの大きさでは、膜厚を５０μｍまで薄化することができ、図５に示すように、固体燃料電池セル５を複数個同時にエポキシ樹脂枠６で補強することが可能であることが判明した。
【００５８】
このエポキシ樹脂枠６では、固体燃料電池セル５の上面は、矩形の開口から空気供給路に臨むとともに、固体燃料電池セル５の下面は、エポキシ樹脂枠６内に形成された水素流路に臨んでいる。
なお、図５において、矢符は、水素流路および空気供給の方向をそれぞれ示している。
【００５９】
本実施例で明らかなように、強度を樹脂で補強することにより、薄板化が困難な材料についても、電池の電解質として使用できることが確認された。
【００６０】
なお、本実施例では、樹脂にエポキシ系樹脂を用いたが、他の樹脂、例えばポリプロピレン系、ポリエチレン系、ポリアミド系、ポリイミド系、シリコン系、テフロン系の樹脂を用いても勿論よい。
【００６１】
（実施例３）
本実施例では、電極材料に白金を主成分とする材料、白金坦持カーボン、または、微粒子白金とＢａ（Ｚｒ_１−ｘＣｅ_ｘ）_１−ｙＭ_ｙＡｌ_ｚＯ_{３− α}、（Ｍは３価の希土類元素およびＩｎの群から選ばれた１種または２種以上の元素、１≧ｘ≧０、０．３＞ｙ＞０、０．０４＞ｚ≧０、１．５＞α＞０）で表される組成の酸化物プロトン伝導体の固体電解質との混合物を電極に用いるものである。
【００６２】
上記実施例１と同様の焼結体電解質に、各種電極を接着し、燃料電池発電特性を調べた。本実施例では、電解質材料に厚さ２２０μｍのＢａＺｒ_０．４Ｃｅ_０．４Ｉｎ_０．２Ｏ_{３− α}を電解質に用いた。電極材料として、実施例１で用いた白金ペースト以外に、微粒子白金ペースト、金、銀、銅、ニッケルの各種ペースト、白金坦持カーボンペースト、および、微粒子白金とＢａＺｒ_０．４Ｃｅ_０．４Ｉｎ_０．２Ｏ_{３− α}とを重量比で１：１に混合した混合物をペースト化したものを試験した。なお、本実施例では、ペーストは、ポリビニルアルコール２ｗｔ％をトルエンで希釈し、粘度をテルピネオールを滴下して調整した。また、各種金属ペースト接着には、８５０℃、３時間で焼き付け、白金坦持カーボンペーストは２００℃でプレスしながら接着を行った。
【００６３】
図６に各種電極を用いたときの２００℃における電池の出力特性（Ｉ−Ｖ特性）を示す。この図６においては、ラインＬ１は、高温焼付け白金、ラインＬ２は、微粒子白金、ラインＬ３は、白金担持カーボン、ラインＬ４は、微粒子白金と電解質との混合物の各電極の出力特性をそれぞれ示している。
【００６４】
金や銀、銅、ニッケルなどのペーストでは充分な特性が得られなかった。一方、白金をベースにした材料では、出力が現れ、特に微粒子白金を用いたものや、白金坦持カーボンのものは高い出力が得られた。また、微粒子白金と電解質材料との混合物でも高い出力が得られることが判明した。
【００６５】
本実施例で、明らかなように、本酸化物プロトン伝導体（電解質材料）と白金微粒子との混合物、または、白金坦持カーボンを用いることにより、より高い電池出力を取り出せることが確認された。また、白金微粒子と電解質との混合物電極は、高い電池特性が得られると共に、薄板電解質の強度を補強する意味でも、効果が大きい。実際に実施例２で示した抗折強度試験により測定すると、約２倍の重さまで強度があることがわかった。
【００６６】
なお、本実施例では、微粒子白金と電解質材料との混合比を１：１にした例を示したが、１：２でも、２：１でもよいし、電解質材料と全く同じ組成のものでなくてもよい。また、本実施例では、２０〜３０ｎｍの白金微粒子を用いたが、それ以外の微粒子でも勿論よい。
【００６７】
（実施例４）
本実施例は、酸化物プロトン伝導体の固体電解質と、白金を主成分とする触媒性能を有する電極と、白金を担持する多孔質体で構成される多孔質電極とを備え、多孔質電極上に固体電解質膜が形成される構造の燃料電池と、その製法を示すものである。
【００６８】
燃料電池の電解質としては、上述したように、薄くすれば（電極間距離を小さくすれば）膜の電気抵抗が減少するので、取り出せる電気量（電流出力）を向上させることができる。従って、電解質は薄く緻密に作製することが必要となる。しかしながら、電解質を薄化すると機械的強度が小さくなり、電池を構成することが困難になる。
【００６９】
本実施例では、多孔質電極に強度を持たせることを特徴としている。
【００７０】
本実施例では、電解質材料にＢａＣｅ_０．８Ｇｄ_０．２Ａｌ_０．０２Ｏ_{３− α}を用いた。酢酸バリウム、酸化セリウム、酸化ガドリニウム、水酸化アルミニウムを所定量計り取り、アルコール溶媒中、乳鉢続いて、ボールミルで粉砕混合をし、平均粒度が１ミクロン以下になるまで粉砕混合した。
【００７１】
混合粉体を脱脂し、その後充分に乾燥させた。この粉末をセラミックの容器に移し、１０５０℃で１２時間焼成を行い、取り出し後、非水溶媒のベンゼンを用いて遊星ボールミル粉砕を行った。遊星ボールミル粉砕では、粒度を１ミクロン以下に粉砕した。粉砕した粉末を真空乾燥機で充分脱水し、粒径１ミクロン以下の白金粉末と１対１の体積比でトルエン中で混合し、これにポリビニルアルコールを１０ｗｔ％混合し、さらに可塑剤としてジブチルテレフタレートを５ｗｔ％加えてスラリーを調整した。なお、溶媒のトルエンは粉体に対して重量比で半分の量とした。
【００７２】
このスラリーをポリエチレンテレフタレートのシート上にドクターブレイド法により１ｍｍ厚のシートに成形した。脱泡乾燥の後、電気炉中で１１００℃で８時間焼成した。
【００７３】
出来上がったシートは、気孔率約２０％で、厚さ０．７ｍｍの多孔質な白金サーメット（多孔質電極）であった。またこのシートの抗折強度は、前記実施例２の測定方法で、１ｋｇ重の重さに耐えうるものであった。
【００７４】
次に図７に断面図に示される燃料電池セルを作製した。予め焼結法で作製した緻密な１００μｍのＢａＣｅ_０．８Ｇｄ_０．２Ａｌ_０．０２Ｏ_{３− α}電解質膜７に白金電極８を焼き付けた。次に、上述のようにして得られた多孔質電極９の一方の面にカーボンブラック電極１０を塗布し、電解質膜７と熱圧着し、燃料電池セルを作製した。図６に示されるように、多孔質電極９が電解質膜７を支持補強する構造材料として機能することがわかる。
【００７５】
このセルに実施例１と同様に水素と空気を供給し、セルの発電特性を調べた。安定に出力は取り出され、室温で最大０．００４ｍＷ／ｃｍ^２の出力が得られた。室温で燃料電池として作動することが確認された。
【００７６】
なお、本実施例では、多孔質電極を作製するのにシート成形後、焼成して作製する方法を示したが、シートにする必要はなく、バルク体でもよいし、また、スラリー調整のバインダー、溶媒は他の物質を用いてもよいし、混合量も規定するものではない。勿論スラリーは如何なる方法で調整してもよいし、実施例では電解質膜は、焼結体から作製されたものであるが、シートから作製されたものでもよいし、蒸着やスパッタなどの気相法を用いてもよい。
【００７７】
（実施例５）
本実施例は、酸化物プロトン伝導体の電解質が、緻密焼結体と多孔焼結体との一体構造体である固体電解質型燃料電池と、その製法を示すものである。この製法は、電解質スラリーのシートから焼結する方法であって、有機バインダー量を変えたグリ−ンシートを作製し、少なくとも２種以上のシートを重ね合わせて共焼結するものである。
【００７８】
本実施例では電解質材料に、ＢａＺｒ_０．６Ｃｅ_０．２Ｇｄ_０．２Ａｌ_０．０２Ｏ_{３− α}を用いた。酢酸バリウム、水酸化ジルコニウム、酸化セリウム、酸化ガドリニウム、水酸化アルミニウムを所定量計り取り、アルコール溶媒中、乳鉢続いて、ボールミルで粉砕混合をし、平均粒度が１ミクロン以下になるまで粉砕混合した。
【００７９】
混合粉体を脱脂し、その後充分に乾燥させた。この粉末をセラミックの容器に移し、１３００℃で１２時間焼成を行い、取り出し後、非水溶媒のベンゼンを用いて遊星ボールミル粉砕を行った。遊星ボールミル粉砕では、粒度を１ミクロン以下に粉砕した。粉砕した粉末を真空乾燥機で充分脱水し、乾燥電解質粉末を得る。この粉末に溶媒として酢酸ブチルとブチルセロソルブの混合溶媒（重量比で４：１）を粉末重量の半分の量で溶かし込み、まず、ボールミル混合粉砕を行った。５φジルコニアボールとポリエチレン容器で２４時間粉砕し、粉砕後、＃３２メッシュフィルターを通してメディアのボールとスラリーを分離した。
【００８０】
ここで、２種のスラリーを調整する。一つは緻密膜用、もう一つは多孔質膜用である。
【００８１】
まず、緻密膜用を調整する。スラリー重量を再測定した後、バインダーとしてポリビニルブチラール（ＰＶＢ）を６ｗｔ％混合し、さらに可塑剤としてブチルベンジルフタレート（ＢＢＰ）を２ｗｔ％加えてスラリーを調整した。なお、溶媒量は粉体に対して重量比で半分の量とした。スラリーを再度ボールミル混合し、真空脱泡した後、ポリエチエンテレフタレートのシート上にドクターブレイド法によりシート成形した。ドクターブレードギャップは、本実施例では、５００μｍとし、約２０ｍｍ／ｓｅｃの速度でシートを走行させた。塗膜整形後、シートを乾燥させた。得られたシートの厚みは１３０〜１４０μｍの厚さであった。
【００８２】
次に多孔質用膜のスラリーを調整した。前記と同様に、スラリーのバインダー量と可塑剤の量を変更してシートを作製した。本実施例では、バインダーのＰＶＢ量を１２ｗｔ％、可塑剤を４ｗｔ％にした。上記同様にドクターブレードでシート化し、出来上がったグリーンシートの厚みは約１００〜１２０μｍであった。
【００８３】
緻密焼結体と多孔焼結体との一体構造体である燃料電池は、次のようにして作製した。まず、緻密体用グリーンシート１枚、多孔質膜用シート４枚を２ｃｍ角に切り取り、８０℃、４×１０^７Ｐａで加圧して積層した。積層後、更に１５ｍｍ角に切断し、電気炉中に投入し、上下をアルミナ平板で挟んだ。上部のアルミナ板の重量は１００ｇ程度である。この状態で、電気炉を昇温し、１６００℃、１０時間、空気中で焼成した。出来上がったシートは、厚さ約０．３５ｍｍで、緻密膜と多孔体膜との一体焼結体であり、抗折強度は、前記実施例２の測定方法で、１ｋｇ重の重さに耐え得るものであった。また、気密試験を調べたところ、１×１０^−３ｍＬ・ｍｍ／ａｔｍ・ｍｉｎ・ｃｍ^２　以下の通気性で充分な気密性を有していることがわかった。
【００８４】
この一体化電解質を用いて図８の断面図に示される燃料電池セルを作製した。一体化電解質１２の両面に電極として白金カーボンペースト１３を塗布、２００℃でホットプレスし、電池を作製した。このように、多孔質１２_１・緻密１２_２の一体化電解質１２が構造材料としても機能することがわかる。
【００８５】
このセルに実施例１と同様に水素と空気を供給し、セルの発電特性を調べた。安定に出力は取り出され、室温で最大０．００６ｍＷ／ｃｍ^２、３００℃で１ｍＷ／ｃｍ^２の出力が得られた。室温から３００℃まで燃料電池として良好に作動することが確認された。
【００８６】
なお、スラリーの調整は上記実施例に規定されるものではなく、バインダー、溶媒は他の物質を用いてもよいし、混合量も規定するものではないし、ドクターブレードギャップも規定するものではない。また、緻密、多孔質膜一体化電解質を作製するとき、グリーンシートは本実施例では緻密膜用１枚、多孔質膜用４枚を用いたが、例えば緻密膜１枚の両面に多孔質膜用３枚ずつ重ねてもよいし、重ねる枚数も重ね方もセルデザインに従って行ってもよい。勿論、焼成温度、焼成手法はどのようなパターンでもよい。電極作製も規定するものではない。
【００８７】
（実施例６）
本実施例は、酸化物プロトン伝導体の固体電解質と、白金を主成分とする触媒性能を有する電極とで構成され、前記固体電解質が平膜体であって、この平膜体と支持構造体とが一体化構造である燃料電池と、この製法を示すものである。この製法は、酸化物プロトン伝導体の電解質の平膜体と支持構造体との一体化構造体を作製する方法として、電解質スラリーのシートから焼結する方法であって、少なくとも２枚以上のシートを重ね合わせて共焼結して作製するものである。
【００８８】
本実施例では、電解質材料にＢａＺｒ_０．４Ｃｅ_０．４Ｉｎ_０．２Ａｌ_０．０２Ｏ_{３− α}を用いた。上述の実施例５と同様に、酢酸バリウム、水酸化ジルコニウム、酸化セリウム、酸化インジウム、水酸化アルミニウムを所定量計り取り、アルコール溶媒中、乳鉢続いて、ボールミルで粉砕混合をし、平均粒度が１ミクロン以下になるまで粉砕混合した。この混合粉体を脱脂し、その後充分に乾燥さた後、セラミックの容器に移し、１３００℃で１２時間焼成を行った。取り出し後、非水溶媒のベンゼンを用いて遊星ボールミル粉砕を行った。遊星ボールミル粉砕では、粒度を１ミクロン以下に粉砕した。粉砕した粉末を真空乾燥機で充分脱水し、乾燥電解質粉末を得る。この粉末に溶媒として酢酸ブチルとブチルセロソルブの混合溶媒（重量比で４：１）を粉末重量の半分の量で溶かし込み、まず、ボールミル混合粉砕を行った。５φジルコニアボールとポリエチレン容器で２４時間粉砕し、粉砕後、＃３２メッシュフィルターを通してメディアのボールとスラリーを分離した。
【００８９】
次にスラリーを調整する。スラリー重量を再測定した後、バインダーとしてポリビニルブチラール（ＰＶＢ）を６ｗｔ％混合し、さらに可塑剤としてブチルベンジルフタレート（ＢＢＰ）を２ｗｔ％加えてスラリーを調整した。なお、溶媒量は粉体に対して重量比で半分の量とした。スラリーを再度ボールミル混合し、真空脱泡した後、ポリエチエンテレフタレートのシート上にドクターブレイド法によりシート成形した。ドクターブレードギャップは、本実施例では、５００μｍとし、約２０ｍｍ／ｓｅｃの速度でシートを走行させた。塗膜整形後、シートを乾燥させた。得られたシートの厚みは１３０〜１４０μｍの厚さであった。
【００９０】
平膜体と支持構造体とが一体化構造である燃料電池は、次のようにして作製した。まず、グリーンシート１枚をそのまま２ｃｍ角に切り取り、次に２ｃｍ角で幅が１ｃｍになるように枠状にグリーンシートを４枚切り出した。これらのシートを縁を揃えて重ね合わせ、８０℃、４×１０^７Ｐａで加圧して積層した。これを、上下をアルミナ平板で挟んだ状態で電気炉に投入した。上部のアルミナ板の重量は１００ｇ程度である。次に電気炉を昇温し、１６００℃、１０時間、空気中で焼成した。出来上がった一体化焼結体は、縁の厚さ約０．５ｍｍで、平膜体は緻密で厚さは約１００μｍであった。この抗折強度は、前記実施例２の測定方法で、１ｋｇ重の重さに耐えうるものであった。また、気密試験を調べたところ、１×１０^−３ｍＬ・ｍｍ／ａｔｍ・ｍｉｎ・ｃｍ^２　以下の通気性で充分な気密性を有していることがわかった。
【００９１】
この平膜体と支持体の一体化電解質を用いて図９の断面図に示される燃料電池セルを作製した。一体化電解質１４の両面に電極１５として白金ペーストを塗布、８５０℃で焼成し、電池を作製した。
【００９２】
このように、平膜体１４_１と支持体１４_２の一体化電解質１４が構造材料としても機能することがわかる。
【００９３】
このセルに実施例１と同様に水素と空気を供給し、セルの発電特性を調べた。安定に出力は取り出され、室温で最大０．００３ｍＷ／ｃｍ^２、３００℃で０．５ｍＷ／ｃｍ^２の出力が得られた。室温から３００℃まで燃料電池として良好に作動することが確認された。
【００９４】
なお、スラリーの調整は、上記実施例に規定されるものではなく、バインダー、溶媒は他の物質を用いてもよいし、混合量も規定するものではないし、ドクターブレードギャップも規定するものではない。また、平膜体、支持体一体化電解質を作製するとき、グリーンシートは本実施例では平板シート１枚、切り抜きシート４枚を用いたが、例えば平板シート２枚で、切り抜きシート５枚重ねてもよいし、切り抜き方もセルデザインに従って行ってよい。勿論、焼成温度、焼成手法はどのようなパターンでもよい。電極作製も規定するものではない。
【００９５】
（実施例７）
本実施例では、実際にハウジングおよびセパレータにカーボン材料やステンレス鋼を用いて集合電池として組立て、安定に作動する実施例を示すものである。
【００９６】
まず、最初にステンレス鋼をハウジングおよびセパレータに用いた例を示す。図１０に本実施例で作製した燃料電池の構成を示す。固体電解質１６に、直径１３ｍｍ、厚さ２２０μｍのＢａＺｒ_０．４Ｃｅ_０．４Ｉｎ_０．２Ａｌ_０．０２Ｏ_{３− α}を用い、同図において、上面側のアノード、下面側のカソードには、白金材料を用いて形成した。これを保持するセラミック製の基盤１７に接着した。
【００９７】
この接着は、直径９ｍｍの４つの開口を有するとともに、前記開口を中心として直径１３．５ｍｍの固体電解質１６収納用の円形の凹部が形成された基盤１７の前記凹部に、アノードおよびカソードが形成された固体電解質１６を収納してその周縁部を接着して前記開口からアノードおよびカソードが臨むように行った。
【００９８】
さらに、上下からステンレス製の集電体兼セパレータ１８でセルが構成されている。なお、この実施例では、集電体兼セパレータ１８は、ハウジングも兼用している。
【００９９】
ステンレス鋼は、ＳＵＳ３０４を使用しており、Ｃｒ含有量は１８％、Ｎｉ８％、Ｆｅ７１％、その他の元素３％で構成されている。また、その熱膨張係数は１１×１０^−６／Ｋであり、電解質、セラミック基板の熱膨張係数も各々１０．５×１０^−６／Ｋ、１１×１０^−６／Ｋとほぼ近い。この燃料電池の総電極面積は２ｃｍ^２である。
【０１００】
このセルを、２００℃に保温しながら、アノード、カソードに、矢符でそれぞれ示されるように各々水素、空気を５０ｃｃ／ｍｉｎの流速で流し、発電試験を行った。この集合電池が良好に発電できた結果を図１１に示す。集合電池の発電特性は単セルの発電のトータルと等しく、集合電池として機能することがわかった。また、ＳＵＳ３０４の加工は酸化物と比較して容易であり、コストも安価である。また、耐久性に優れている。
【０１０１】
なお、本実施例では電解質にＢａＺｒ_０．４Ｃｅ_０．４Ｉｎ_０．２Ａｌ_０．０２Ｏ_{３− α}と電極に白金を用いた事例を示したが、他のプロトン電導性酸化物でも勿論良いし、電極も白金でないくても良い。また、本実施例では集電体兼セパレーターにＳＵＳ３０４ステンレス鋼を用いた例を示したが、ステンレス鋼はＳＵＳ４３０でもよいし、クロム元素が１８％以下の鉄成分が主成分の金属でもよいし、カーボン材料や樹脂材料でもよい。なお、集電体を樹脂材料で構成する場合には、集電用の配線を設けておけばよい。また、電解質を保持する基盤として、セラミックス製のものを用いたが、デザイン及び材質は何でも良い。
【０１０２】
なお、ステンレス鋼は、鉄を主成分とし、２０％以下のクロム元素を含むのが好ましく、このステンレス鋼の熱膨張係数は、９〜１５×１０^−６／Ｋであるのが好ましい。
【０１０３】
（実施例８）
本実施例では、カーボン材料をセパレータに用いた例を示す。図１２に本実施例で作製した３セルスタック燃料電池の構成を示す。固体電解質１９に、２０ｍｍ角、厚さ２８０μｍのＢａＺｒ_０．６Ｃｅ_０．２Ｇｄ_０．２Ａｌ_０．０２Ｏ_{３− α}を用い、アノード２０、裏面側のカソードには、白金材料を用いて形成した。これをカーボン材料で作製したセパレータ２１をセルの上下に配し、集合電池を構成している。カーボン材料は、東海カーボン製Ｇ３４７等方性黒鉛材を用いている。熱膨張係数は４．２×１０^−６／Ｋであり、抵抗は１１μΩｍである。この燃料電池の総電極面積は６．７５ｃｍ^２である。このセルを、２００℃に保温しながら、アノード２０、カソードに各々水素、空気を５０ｃｃ／ｍｉｎの流速で流し、発電試験を行った。なお、２１_１，２１_２は、水素の入口と出口とをそれぞれ示し、２１_３，２１_４は、空気の入口と排ガスの出口とをそれぞれ示している。
【０１０４】
この集合電池が良好に発電できた結果を図１３に示す。集合電池の発電特性は単セルの発電のトータルと等しく、集合電池として機能することがわかった。また、カーボンの加工は酸化物と比較して容易であり、コストも安価である。また、耐久性に優れている。
【０１０５】
なお、本実施例では電解質に２０ｍｍ角、厚さ２８０μｍのＢａＺｒ_０　．６Ｃｅ_０．２Ｇｄ_０．２Ａｌ_０．０２Ｏ_{３− α}と電極に白金を用いた例を示したが、他のプロトン電導性酸化物でも勿論良いし、電極も白金でないくても良いし形状、サイズも規定するものではない。また、本実施例ではセパレータに東海カーボン製Ｇ３４７等方性黒鉛材を用を用いた例を示したが、カーボン材はＧ３４８でもＳｉＣコーティングのものでも良い、主成分が黒鉛で形成されているものであればどのようなものでも良い。また、カーボン材料に代えて、ステンレス鋼などの金属や樹脂材料を用いてもよい。もちろん、形状、サイズは規定するものではない。
【０１０６】
なお、図１４には、図１２の集合電池を収納したハウジングの概略図を示す。同図において、２５は樹脂材料からなる本体ハウジングであり、２６は金属材料からなるガス供給部であり、２７は、金属材料からなる集電体（集電ハウジング）である。
【０１０７】
（その他の実施例）
燃料電池の出力は、電解質膜のイオン導電率（Ｓ／ｃｍ）が高いほど、また膜厚（ｃｍ）が小さいほど出力は高くなる。これを考慮した数値として、面積抵抗率（Ωｃｍ^２）がある。面積抵抗率が小さいほど、電池出力は大きくなる。面積抵抗率は、次式によって与えられる。
【０１０８】

本実施例では、０．００１ｍＷ／ｃｍ^２を電池発電の下限値とし、このときの面積抵抗率（約１００００Ωｃｍ^２）を基準にして、電解質膜を、良好な材料◎、適用可能な材料○、適用困難な材料×の３段階で評価した。その結果を表３に示す。なお、表３では、室温での最小面積抵抗率を示している。
【０１０９】
【表３】

本発明の電解質材料は、良好な材料◎または適用可能な材料○として評価された。
【０１１０】
【発明の効果】
以上のように本発明によれば、溶液の蒸発、散出、あるいは漏液のないウォターフリーの固体電解質型燃料電池において、機械的強度に優れるとともに、５００℃未満の室温付近までの低温で、電池出力を得ることができる。
【０１１１】
また、本発明の固体電解質型燃料電池は、固体電解質を、樹脂材料からなる支持構造体で支持するので、固体電解質の膜の機械的強度を補強することができる。
【０１１２】
また、本発明の固体電解質型燃料電池は、セパレータ、集電体およびハウジングの少なくともいずれか一つを、樹脂材料、カーボン材料および金属材料の少なくともいずれか一つで構成しているので、従来のセラミックスなどに比べて加工性が良好であって、コストの削減を図ることができる。
【図面の簡単な説明】
【図１】本発明の実施例に係る固体電解質型燃料電池の概略断面図である。
【図２】本実施例における発電特性例を示す図である。
【図３】本実施例における抗折強度試験を示す図である。
【図４】本実施例における樹脂による電解質補強例を示す図である。
【図５】本実施例における樹脂による電解質補強の燃料電池セル例を示す図である。
【図６】本実施例における発電特性を示す図である。
【図７】本実施例における電池セルの断面図である。
【図８】本実施例における電池セルの断面図である。
【図９】本実施例における電池セルの断面図である。
【図１０】集合電池の分解斜視図である。
【図１１】図１０の発電特性を示す図である。
【図１２】他の集合電池の分解斜視図である。
【図１３】図１２の発電特性を示す図である。
【図１４】ハウジングを含む集合電池の概略構成図である。
【符号の説明】
１，４　　　　　試料
２，７　　　　　電解質膜
３，６　　　　　エポキシ樹脂枠
５　　　　　　　電池セル
８，１５　　　　　白金電極
９　　　　　　　多孔質電極
１０　　　　　　カーボンブラック電極
１２　　　　　　緻密膜多孔質一体化電解質
１３　　　　　　白金カーボン電極
１４　　　　　　平膜体支持体一体化電解質[0001]
[Industrial applications]
The present invention relates to a solid oxide fuel cell and a method for manufacturing the same.
[0002]
[Prior art]
Fuel cells are being developed as stationary and mobile power sources for consumer use as power generation devices and devices that are clean and energy-saving. Specifically, it is receiving attention as a power source for home cogeneration and electric vehicles.
[0003]
Depending on the electrolyte, there are fuel cells that operate at around room temperature and those that operate at high temperatures around 1000 ° C. Currently, fuel cells that are actively developed are those that operate at 100 ° C or lower. This is a polymer fuel cell using an organic polymer as an electrolyte.
[0004]
Most of the polymer electrolyte used in this type is a perfluorocarbon sulfonic acid membrane (trade name: Nafyon) membrane developed by DuPont and has a high proton conductivity (1 × 10 4) from room temperature to around 100 ° C.^-2From 1 × 10^-1S / cm).
[0005]
In recent years, a very small fuel cell called a micro fuel cell has been attracting attention as a portable power source replacing the secondary battery. A Nafyon membrane is also being studied for this type of electrolyte membrane. A fuel cell is a mechanism to extract electricity by supplying gaseous fuel such as hydrogen and air, and the fuel is usually used for mobile and portable fuels. (For example, see Patent Document 1).
[0006]
At present, in a polymer fuel cell using a Nafyon membrane, it is necessary to maintain the Nafyon membrane in a saturated water-containing state, and it is necessary to control the water content.
[0007]
On the other hand, solid electrolyte fuel cells are so-called water-free because the electrolyte is solid, and the entire fuel cell can be configured without using a liquid. there is no problem.
[0008]
[Patent Document 1]
JP 2001-143714 A
[0009]
[Problems to be solved by the invention]
However, in a conventional solid oxide fuel cell, a phenomenon in which protons are conducted at a temperature of 500 ° C. or less in an oxide ion conductor as an electrolyte has not yet been reported. That is, in the case of the oxide proton conductor, although thinning is considered to reduce the membrane resistance, it is limited to about 450 μm due to the problem of the mechanical strength of the membrane. There is a problem that heating at a temperature of at least ℃ is required, so that it cannot be used for applications such as a cogeneration system having a temperature of less than 500 ° C or a portable power supply at around room temperature.
[0010]
In the case of a solid oxide fuel cell that operates at a high temperature of about 1000 ° C., when fabricating an assembled cell, ceramics or heat-resistant alloys having poor workability and high cost are used as separators and housing materials. There is also a problem of not gaining.
[0011]
The present invention has been made in view of the above points, and in a solid oxide fuel cell, a battery output can be obtained even at a low temperature of less than 500 ° C., and the solid oxide fuel cell can be processed as a separator or a housing material. It is an object of the present invention to provide a solid oxide fuel cell capable of using a low-cost and easy-to-use material and a method for manufacturing the same.
[0012]
[Means for Solving the Problems]
The present invention has the following configuration to achieve the above object.
[0013]
That is, the solid electrolyte fuel cell of the present invention includes a pair of electrodes, and in a solid electrolyte fuel cell in which a solid electrolyte is provided between the electrodes, the solid electrolyte may be, for example, Ba (Zr_1-xCe_x)_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 1> x> 0, 0.3> y> 0, 0.04> z> 0, 1.. 5> α> 0).
[0014]
Here, M is one or two or more elements selected from the group of trivalent rare earth elements and In as described above. As the trivalent rare earth elements, La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, and Y. In the case where the composition is composed of two or more elements, the sum of the composition ratios of those elements becomes_yIn the formula.
[0015]
According to the present invention, by using an oxide proton conductor having the above composition, in a water-free solid oxide fuel cell having no evaporation, diffusion, or leakage of a solution, the mechanical strength is excellent and the temperature is lower than 500 ° C. The battery output can be obtained even at a low temperature up to around room temperature.
[0016]
Further, in the solid oxide fuel cell of the present invention, the support structure supporting the solid electrolyte is made of a resin material.
[0017]
According to the present invention, the mechanical strength of the solid electrolyte membrane can be reinforced by the support structure made of the resin material.
[0018]
In the solid oxide fuel cell of the present invention, at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material.
[0019]
ADVANTAGE OF THE INVENTION According to this invention, workability is favorable compared with the conventional ceramics etc., and cost reduction can be aimed at.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
The solid electrolyte fuel cell of the present invention includes a pair of electrodes, and in the solid electrolyte fuel cell in which the solid electrolyte is provided between the electrodes, the solid electrolyte is formed of Ba (Zr_1-xCe_x)_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 1> x> 0, 0.3> y> 0, 0.04> z> 0, 1.. 5> α> 0) is an oxide proton conductor having a composition represented by the following formula, and can provide a battery output even at a low temperature of less than 500 ° C.
[0021]
In the present invention, the solid electrolyte is BaCe_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 0.3> y> 0, 0.04> z> 0, 1.5> α> 0) , BaZr_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 0.3> y> 0, 0.04> z> 0, 1.5> α> 0) , Ba (Zr_1-xCe_x)_1-yM_yO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 1> x> 0, 0.3> y> 0, 1.5> α> 0), BaCe_1-yM_yO_{3- α}, (M is one or two or more elements selected from the group consisting of trivalent rare earth elements and In, 0.3> y> 0, 1.5> α> 0), or BaZr_1-yM_yO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 0.3> y> 0, 1.5> α> 0) Since it is a proton conductor, a battery output can be obtained even at a low temperature of less than 500C.
[0022]
In the present invention, M in the composition of the oxide proton conductor is preferably composed of one or more elements selected from the group consisting of In, Gd, Y, and Yb.
[0023]
Further, in the present invention, the oxide proton conductor is preferably made of BaCe_0.8Gd_0.2Al_0.02O_{3- α}, BaZr_0.6Ce_0.2Gd_0.2O_{3- α}Or BaZr_0.4Ce_0.4In_0.2O_{3- α}The composition is preferably any one of the following.
[0024]
Further, in the solid oxide fuel cell of the present invention, the electrode is made of platinum-supporting carbon, and a good battery output can be obtained even at a low temperature of less than 500 ° C.
[0025]
Further, in the solid oxide fuel cell of the present invention, the electrode is a mixture of fine particles of platinum and a material having the same component as the oxide proton conductor. Even at a low temperature of less than 500 ° C., a good cell output is obtained. Obtainable.
[0026]
Here, the fine-particle platinum refers to a fine-particle platinum having an average particle size of, for example, 1 μm or less, preferably, for example, a fine-particle platinum having a particle size of 20 to 30 nm.
[0027]
Further, the solid electrolyte fuel cell of the present invention includes a pair of electrodes, in a solid electrolyte fuel cell in which a solid electrolyte is provided between the electrodes, the solid electrolyte is a proton conductor, the solid electrolyte fuel cell One is an electrode containing platinum as a main component, and the other is a porous electrode made of a porous body carrying platinum, and even at a low temperature of less than 500 ° C., a good battery output can be obtained. The porous electrode can also function to reinforce the mechanical strength of the solid electrolyte membrane.
[0028]
Here, the electrode containing platinum as a main component includes a platinum electrode.
[0029]
The solid oxide fuel cell of the present invention includes a pair of electrodes, and in a solid oxide fuel cell in which a solid electrolyte is provided between the electrodes, the electrode is an electrode containing platinum as a main component, and the solid electrolyte Is an oxide proton conductor, which is an integral structure of a membrane and a support structure supporting the membrane, and the mechanical strength of the solid electrolyte membrane is unified. It can be reinforced by a support structure.
[0030]
Further, the solid electrolyte fuel cell of the present invention includes a pair of electrodes, and in a solid electrolyte fuel cell in which a solid electrolyte is provided between the electrodes, the solid electrolyte is an oxide proton conductor, It is an integrated structure of a sintered body and a porous sintered body. Even at a low temperature of less than 500 ° C., a good battery output can be obtained, and the porous sintered body also has a function of increasing mechanical strength. be able to.
[0031]
Here, the dense sintered body does not allow gas to permeate, and the porous sintered body allows gas to permeate.
[0032]
Further, in the solid oxide fuel cell of the present invention, at least one of the separator, the current collector, and the housing is formed of at least one of a resin material, a carbon material, and a metal material. The cost can be reduced by using a material having good workability as compared with the above.
[0033]
Note that the separator and the current collector may be configured to serve both purposes.
[0034]
The method for producing a solid oxide fuel cell according to the present invention comprises stacking at least two sheets of electrolyte slurry and co-sintering them to form an integrated structure of the solid electrolyte and the support structure. As a result, the support structure that increases the mechanical strength of the solid electrolyte membrane can be easily integrated.
[0035]
Further, the method for producing a solid oxide fuel cell according to the present invention is characterized in that sheets of dense and porous electrolyte slurries having different amounts of organic binders are prepared, and at least two or more sheets are laminated and co-fired. The solid electrolyte is made into an integrated structure of a dense sintered body and a porous sintered body, and the porous sintered body that increases the mechanical strength is integrated into the dense sintered body by co-sintering. A solid electrolyte can be obtained.
[0036]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0037]
【Example】
(Example 1)
As shown in FIG. 1, the solid oxide fuel cell according to the embodiment of the present invention includes an oxide proton conductor solid electrolyte 30 and a pair of electrodes 31.
[0038]
In the configuration shown in FIG. 1, the solid oxide fuel cell of this embodiment has a Ba (Zr_1-xCe_x)_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 1 ≧ x ≧ 0, 0.3> y> 0, 0.04> z ≧ 0,. 5> α> 0), comprising a solid electrolyte of an oxide proton conductor having a composition represented by the formula: and an electrode mainly composed of platinum and having catalytic performance, wherein the solid electrolyte has a thickness of 300 μm or less. In this case, the battery is operated from room temperature to 350 ° C. or lower without humidification.
[0039]
In this embodiment, first, a columnar sintered body (diameter: 13 mm, thickness: 10 mm) of an oxide proton conductor serving as a solid electrolyte is synthesized by a high-temperature solid-phase method, and is thinned to 300 μm or less by cutting and polishing. It has become. A platinum paste (manufactured by Tanaka Kikinzoku) was applied to both sides of the disk and baked to produce a fuel cell.
[0040]
Non-humidified hydrogen gas and air were supplied to each electrode of the fuel cell thus manufactured, and the power generation characteristics of the fuel cell were examined. Further, the fuel cell has a structure in which a constant temperature can be maintained by an external heater.
[0041]
FIG. 2 shows BaZr having a thickness of 220 μm._0.4Ce_0.4In_0.2O_{3- α}An example of power generation characteristics (IV characteristics) at various temperatures of a battery cell using as a solid electrolyte is shown.
[0042]
That is, FIG. 2 shows the terminal voltage (mv) and output current (μA / cm) at 200 ° C. and 350 ° C.²), Power density (mW / cm²).
[0043]
As is clear from this figure, it was confirmed that power generation was possible even at 200 ° C. without humidification.
[0044]
Table 1 below shows the electrolyte film thickness of a plurality of fuel cells using the oxide proton conductor (electrolyte material) having the composition of the present invention as a solid electrolyte, and the power generation characteristics at a plurality of temperatures. This shows the relationship with the maximum output density.
[0045]
[Table 1]

As is evident from Table 1, an electrolyte material that generates power even at around room temperature without humidification was confirmed. It is considered that it was an unconventional technique that power generation was confirmed at such a temperature as an oxide proton conductor.
[0046]
According to the present invention, it is possible to provide a solid oxide fuel cell capable of generating electric power near room temperature by using an electrolyte material whose proton conduction is confirmed near room temperature and a thinning technique. Of course, it is clear from FIG. 2 and Table 1 that power can be generated even at a temperature higher than room temperature, for example, 300 ° C. or 500 ° C.
[0047]
(Example 2)
In the case of the oxide proton conductor, as the thickness of the electrolyte is reduced, the internal resistance of the battery can be reduced, and the output characteristics of the battery can be improved.
[0048]
However, thinning by machining and polishing largely depends on the mechanical strength of the material. Conventional proton conductor materials have a thickness of 450 μm to 500 μm as a limit, but in general, one practical guideline is whether or not the material can be reduced to 300 μm or less with an electrolyte alone. That is, in the present invention, the solid electrolyte preferably has a film structure of 300 μm or less.
[0049]
Accordingly, the mechanical strength of the electrolyte materials, which are the plurality of proton conductor materials shown in Table 1 of Example 1 described above, was evaluated as follows.
[0050]
That is, the electrolyte material obtained by the sintering method used in the above-mentioned Example 1 was used as a sample and thinned by mechanical polishing. As shown in FIG. Was polished, and both sides of this sample 1 were supported at an interval of 10 mm, and a 1 kg weight was applied to the center diameter portion to evaluate the bending strength.
[0051]
Table 2 below shows the limit film thickness that can withstand the 1 kg weight.
[0052]
[Table 2]

As shown in Table 2, there are some solid electrolytes alone that maintain strength up to a film thickness of 100 μm, but most of them can be thinned by mechanical polishing up to a film thickness of about 300 μm. Was done.
[0053]
In this embodiment, the resin having insufficient mechanical strength is reinforced with resin.
[0054]
In this embodiment, similarly to the above, the sintered body electrolyte is cut out and thinned by polishing. As shown in FIG. 4, the periphery of the thinned solid electrolyte membrane 2 was reinforced with an epoxy resin frame 3 as a support structure.
[0055]
The epoxy resin frame 3 has a thickness of 1 mm, and has a 3 mm × 3 mm opening at the center of a 9 mm × 9 mm rectangle. The periphery of the rectangular solid electrolyte membrane 2 of 5 mm × 5 mm is held at the center of the epoxy resin frame 3, and the upper and lower surfaces of the solid electrolyte membrane 2 are positioned from the opening of the epoxy resin frame 3. It is configured to face. In this example, the solid electrolyte membrane 2 is held at a substantially central position in the thickness direction of the epoxy resin frame 3.
[0056]
A sample 4 having such an epoxy resin frame 3 was subjected to the same test as described above, that is, a support was placed at a position 5 mm apart from the left and right about the diagonal line of the rectangular epoxy resin frame 3, and 1 kg along the diagonal line. The weight was applied to the epoxy resin frame 3.
[0057]
When the strength was examined by this bending strength test, it was confirmed that all of the materials shown in Table 2 were able to withstand a weight of 1 kg. In any of the samples, when the size is 5 mm × 5 mm, the film thickness can be reduced to 50 μm. As shown in FIG. 5, a plurality of solid fuel cells 5 are simultaneously reinforced with an epoxy resin frame 6. It turned out to be possible.
[0058]
In the epoxy resin frame 6, the upper surface of the solid fuel cell 5 faces the air supply path from the rectangular opening, and the lower surface of the solid fuel cell 5 faces the hydrogen flow path formed in the epoxy resin frame 6. In.
In FIG. 5, arrows indicate the directions of the hydrogen flow path and the air supply, respectively.
[0059]
As is evident from the present example, it was confirmed that, by reinforcing the strength with a resin, even a material that is difficult to make thin can be used as an electrolyte of a battery.
[0060]
In this embodiment, the epoxy resin is used as the resin. However, other resins such as a polypropylene resin, a polyethylene resin, a polyamide resin, a polyimide resin, a silicon resin, and a Teflon resin may be used.
[0061]
(Example 3)
In this embodiment, a material containing platinum as a main component, platinum-supported carbon, or fine particles of platinum and Ba (Zr_1-xCe_x)_1-yM_yAl_zO_{3- α}, (M is one or more elements selected from the group consisting of trivalent rare earth elements and In, 1 ≧ x ≧ 0, 0.3> y> 0, 0.04> z ≧ 0,. 5> α> 0) is used for the electrode as a mixture of the oxide proton conductor and the solid electrolyte.
[0062]
Various electrodes were bonded to the same sintered electrolyte as in Example 1 above, and the power generation characteristics of the fuel cell were examined. In this embodiment, the electrolyte material is BaZr having a thickness of 220 μm._0.4Ce_0.4In_0.2O_{3- α}Was used for the electrolyte. As the electrode material, in addition to the platinum paste used in Example 1, fine-particle platinum paste, various pastes of gold, silver, copper, and nickel, platinum-carrying carbon paste, and fine-particle platinum and BaZr_0.4Ce_0.4In_0.2O_{3- α}And a mixture obtained by mixing 1: 1 by weight ratio into a paste was tested. In this example, the paste was prepared by diluting 2 wt% of polyvinyl alcohol with toluene and adjusting the viscosity by dropping terpineol. For bonding various metal pastes, baking was performed at 850 ° C. for 3 hours, and the platinum-carrying carbon paste was bonded while pressing at 200 ° C.
[0063]
FIG. 6 shows output characteristics (IV characteristics) of the battery at 200 ° C. when various electrodes are used. In FIG. 6, the line L1 indicates the output characteristics of high-temperature baked platinum, the line L2 indicates the fine particle platinum, the line L3 indicates the platinum-supporting carbon, and the line L4 indicates the output characteristics of each electrode of the mixture of the fine particle platinum and the electrolyte. I have.
[0064]
Sufficient properties could not be obtained with pastes of gold, silver, copper, nickel and the like. On the other hand, in the case of a platinum-based material, an output appeared, and in particular, those using fine-particle platinum and platinum-supported carbon provided high output. It has also been found that a high output can be obtained even with a mixture of fine-particle platinum and an electrolyte material.
[0065]
In this example, it is apparent that a higher battery output can be obtained by using a mixture of the present oxide proton conductor (electrolyte material) and platinum fine particles or using platinum-supported carbon. In addition, the mixture electrode of the platinum fine particles and the electrolyte has high effects in terms of obtaining high battery characteristics and reinforcing the strength of the thin plate electrolyte. When actually measured by the bending strength test shown in Example 2, it was found that there was a strength up to about twice the weight.
[0066]
In the present embodiment, an example is shown in which the mixing ratio between the fine particle platinum and the electrolyte material is 1: 1. However, the mixing ratio may be 1: 2, 2: 1, or may not be exactly the same as the electrolyte material. You may. In this embodiment, platinum fine particles of 20 to 30 nm are used, but other fine particles may of course be used.
[0067]
(Example 4)
The present example includes a solid electrolyte of an oxide proton conductor, an electrode having catalytic performance containing platinum as a main component, and a porous electrode composed of a porous material carrying platinum. FIG. 1 shows a fuel cell having a structure in which a solid electrolyte membrane is formed on a fuel cell, and a method for producing the fuel cell.
[0068]
As described above, when the electrolyte of the fuel cell is made thinner (when the distance between the electrodes is made smaller), the electric resistance of the membrane is reduced, so that the amount of electricity (current output) that can be extracted can be improved. Therefore, it is necessary to make the electrolyte thin and dense. However, when the electrolyte is thinned, the mechanical strength is reduced, and it is difficult to construct a battery.
[0069]
The present embodiment is characterized in that the porous electrode has strength.
[0070]
In this embodiment, the electrolyte material is BaCe_0.8Gd_0.2Al_0.02O_{3- α}Was used. Predetermined amounts of barium acetate, cerium oxide, gadolinium oxide, and aluminum hydroxide were weighed, pulverized and mixed in an alcohol solvent, followed by a mortar and a ball mill until the average particle size became 1 μm or less.
[0071]
The mixed powder was degreased and then sufficiently dried. The powder was transferred to a ceramic container, baked at 1050 ° C. for 12 hours, taken out, and then subjected to planetary ball milling using benzene as a non-aqueous solvent. In the planetary ball mill pulverization, the particle size was pulverized to 1 micron or less. The pulverized powder is sufficiently dehydrated with a vacuum drier, mixed with platinum powder having a particle size of 1 μm or less in toluene at a volume ratio of 1: 1, mixed with 10 wt% of polyvinyl alcohol, and further, as a plasticizer, dibutyl terephthalate. Was added to prepare a slurry. In addition, toluene as a solvent was used in an amount of half the weight ratio with respect to the powder.
[0072]
This slurry was formed into a 1 mm thick sheet on a polyethylene terephthalate sheet by the doctor blade method. After defoaming and drying, it was baked at 1100 ° C. for 8 hours in an electric furnace.
[0073]
The resulting sheet was a porous platinum cermet (porous electrode) having a porosity of about 20% and a thickness of 0.7 mm. The bending strength of this sheet was such that it could withstand a weight of 1 kg in the measuring method of Example 2 described above.
[0074]
Next, a fuel cell shown in a sectional view in FIG. 7 was produced. Dense 100μm BaCe prepared in advance by sintering method_0.8Gd_0.2Al_0.02O_{3- α}The platinum electrode 8 was baked on the electrolyte membrane 7. Next, a carbon black electrode 10 was applied to one surface of the porous electrode 9 obtained as described above, and was thermocompression-bonded to the electrolyte membrane 7 to produce a fuel cell. As shown in FIG. 6, it can be seen that the porous electrode 9 functions as a structural material for supporting and reinforcing the electrolyte membrane 7.
[0075]
Hydrogen and air were supplied to this cell as in Example 1, and the power generation characteristics of the cell were examined. Output is taken out stably, up to 0.004 mW / cm at room temperature²Output was obtained. It was confirmed that the fuel cell operated at room temperature.
[0076]
In the present embodiment, a method of forming a sheet and then firing the sheet to form a porous electrode has been described.However, it is not necessary to make a sheet, and a bulk body may be used. As the solvent, other substances may be used, and the mixing amount is not specified. Of course, the slurry may be adjusted by any method, and in the embodiment, the electrolyte membrane is made of a sintered body, but may be made of a sheet, or may be a gas phase method such as evaporation or sputtering. May be used.
[0077]
(Example 5)
This example shows a solid oxide fuel cell in which the electrolyte of the oxide proton conductor is an integrated structure of a dense sintered body and a porous sintered body, and a method for producing the same. This manufacturing method is a method of sintering from a sheet of an electrolyte slurry, in which a green sheet having a different amount of an organic binder is produced, and at least two or more sheets are superposed and co-sintered.
[0078]
In this embodiment, the electrolyte material is BaZr._0.6Ce_0.2Gd_0.2Al_0.02O_{3- α}Was used. Predetermined amounts of barium acetate, zirconium hydroxide, cerium oxide, gadolinium oxide, and aluminum hydroxide were weighed, pulverized and mixed in an alcohol solvent, followed by a mortar, and then a ball mill until the average particle size became 1 micron or less.
[0079]
The mixed powder was degreased and then sufficiently dried. This powder was transferred to a ceramic container, baked at 1300 ° C. for 12 hours, taken out, and then subjected to planetary ball milling using benzene as a non-aqueous solvent. In the planetary ball mill pulverization, the particle size was pulverized to 1 micron or less. The pulverized powder is sufficiently dehydrated with a vacuum drier to obtain a dry electrolyte powder. As a solvent, a mixed solvent of butyl acetate and butyl cellosolve (weight ratio: 4: 1) was dissolved in the powder in an amount of half the weight of the powder, and the mixture was first subjected to ball mill mixing and pulverization. The mixture was crushed for 24 hours with 5φ zirconia balls and a polyethylene container, and after crushing, the media balls and the slurry were separated through a # 32 mesh filter.
[0080]
Here, two types of slurries are prepared. One is for dense membranes and the other is for porous membranes.
[0081]
First, a fine film is prepared. After re-measurement of the slurry weight, 6 wt% of polyvinyl butyral (PVB) was mixed as a binder, and 2 wt% of butylbenzyl phthalate (BBP) was further added as a plasticizer to prepare a slurry. Note that the amount of the solvent was set to half the weight ratio with respect to the powder. The slurry was mixed in a ball mill again and defoamed in vacuum, and then formed into a sheet on a polyethylene terephthalate sheet by a doctor blade method. In this embodiment, the doctor blade gap was set to 500 μm, and the sheet was run at a speed of about 20 mm / sec. After shaping the coating, the sheet was dried. The thickness of the obtained sheet was 130 to 140 μm.
[0082]
Next, the slurry for the porous film was prepared. Similarly to the above, a sheet was prepared by changing the amount of the binder and the amount of the plasticizer in the slurry. In the present example, the amount of PVB in the binder was 12 wt% and the amount of the plasticizer was 4 wt%. The sheet was formed into a sheet by a doctor blade in the same manner as described above, and the thickness of the completed green sheet was about 100 to 120 μm.
[0083]
A fuel cell as an integrated structure of a dense sintered body and a porous sintered body was manufactured as follows. First, one green sheet for dense body and four sheets for porous membrane were cut into 2 cm square,⁷The layers were laminated under pressure at Pa. After lamination, it was further cut into 15 mm squares, placed in an electric furnace, and sandwiched between upper and lower alumina flat plates. The weight of the upper alumina plate is about 100 g. In this state, the temperature of the electric furnace was increased, and firing was performed at 1600 ° C. for 10 hours in the air. The finished sheet is about 0.35 mm thick and is an integral sintered body of a dense membrane and a porous membrane. The bending strength can withstand a weight of 1 kg weight by the measuring method of Example 2. Was something. In addition, when an airtight test was conducted, 1 × 10^-3mL ・ mm / atm ・ min ・ cm²It was found that the following air permeability had sufficient airtightness.
[0084]
Using this integrated electrolyte, a fuel cell shown in the sectional view of FIG. 8 was produced. A platinum carbon paste 13 was applied as electrodes to both surfaces of the integrated electrolyte 12 and hot-pressed at 200 ° C. to produce a battery. Thus, the porous 12₁・ Dense 12₂It can be seen that the integrated electrolyte 12 also functions as a structural material.
[0085]
Hydrogen and air were supplied to this cell as in Example 1, and the power generation characteristics of the cell were examined. Output is taken out stably, up to 0.006 mW / cm at room temperature²1 mW / cm at 300 ° C²Output was obtained. It has been confirmed that the fuel cell operates well from room temperature to 300 ° C.
[0086]
The adjustment of the slurry is not stipulated in the above embodiment, and other substances may be used for the binder and the solvent, and the mixing amount is not specified, and the doctor blade gap is not specified. When a dense and porous membrane-integrated electrolyte is produced, one green sheet and four porous membranes are used in this embodiment, but for example, a porous membrane is provided on both sides of one dense membrane. For example, three sheets may be stacked, and the number of sheets to be stacked and the manner of stacking may be performed according to the cell design. Of course, any pattern may be used for the firing temperature and the firing method. The electrode preparation is not specified.
[0087]
(Example 6)
This embodiment is composed of a solid electrolyte of an oxide proton conductor and an electrode having catalytic performance mainly composed of platinum, and the solid electrolyte is a flat membrane, and the flat membrane and the support structure 1 and 2 show a fuel cell having an integrated structure and this manufacturing method. This manufacturing method is a method of sintering from a sheet of an electrolyte slurry as a method of producing an integrated structure of a flat membrane of an electrolyte of an oxide proton conductor and a support structure, and at least two sheets or more. Are superposed and co-sintered.
[0088]
In this embodiment, the electrolyte material is BaZr._0.4Ce_0.4In_0.2Al_0.02O_{3- α}Was used. In the same manner as in Example 5 described above, barium acetate, zirconium hydroxide, cerium oxide, indium oxide, and aluminum hydroxide were weighed and measured in a predetermined amount. The mixture was pulverized and mixed until the size became less than micron. This mixed powder was degreased and then sufficiently dried, then transferred to a ceramic container and baked at 1300 ° C. for 12 hours. After the removal, planetary ball milling was performed using benzene as a non-aqueous solvent. In the planetary ball mill pulverization, the particle size was pulverized to 1 micron or less. The pulverized powder is sufficiently dehydrated with a vacuum drier to obtain a dry electrolyte powder. As a solvent, a mixed solvent of butyl acetate and butyl cellosolve (weight ratio: 4: 1) was dissolved in the powder in an amount of half the weight of the powder, and the mixture was first subjected to ball mill mixing and pulverization. The mixture was crushed for 24 hours with 5φ zirconia balls and a polyethylene container, and after crushing, the media balls and the slurry were separated through a # 32 mesh filter.
[0089]
Next, the slurry is adjusted. After re-measurement of the slurry weight, 6 wt% of polyvinyl butyral (PVB) was mixed as a binder, and 2 wt% of butylbenzyl phthalate (BBP) was further added as a plasticizer to prepare a slurry. Note that the amount of the solvent was set to half the weight ratio with respect to the powder. The slurry was mixed in a ball mill again and defoamed in vacuum, and then formed into a sheet on a polyethylene terephthalate sheet by a doctor blade method. In this embodiment, the doctor blade gap was set to 500 μm, and the sheet was run at a speed of about 20 mm / sec. After shaping the coating, the sheet was dried. The thickness of the obtained sheet was 130 to 140 μm.
[0090]
A fuel cell in which the flat membrane and the support structure had an integrated structure was manufactured as follows. First, one green sheet was cut into a 2 cm square as it was, and then four green sheets were cut out in a frame shape so that the width was 1 cm at a 2 cm square. These sheets are overlapped with their edges aligned at 80 ° C., 4 × 10⁷The layers were laminated under pressure at Pa. This was charged into an electric furnace with the upper and lower portions sandwiched between alumina flat plates. The weight of the upper alumina plate is about 100 g. Next, the temperature of the electric furnace was increased, and firing was performed in air at 1600 ° C. for 10 hours. The resulting integrated sintered body had an edge thickness of about 0.5 mm, and the flat film body was dense and had a thickness of about 100 μm. The flexural strength was able to withstand a weight of 1 kg by the measuring method of Example 2. In addition, when an airtight test was conducted, 1 × 10^-3mL ・ mm / atm ・ min ・ cm²It was found that the following air permeability had sufficient airtightness.
[0091]
A fuel cell shown in the cross-sectional view of FIG. 9 was produced using the integrated electrolyte of the flat membrane and the support. A platinum paste was applied as electrodes 15 to both surfaces of the integrated electrolyte 14 and baked at 850 ° C. to produce a battery.
[0092]
Thus, the flat membrane 14₁And support 14₂It can be seen that the integrated electrolyte 14 also functions as a structural material.
[0093]
Hydrogen and air were supplied to this cell as in Example 1, and the power generation characteristics of the cell were examined. Output is taken out stably, up to 0.003 mW / cm at room temperature²0.5 mW / cm at 300 ° C²Output was obtained. It has been confirmed that the fuel cell operates well from room temperature to 300 ° C.
[0094]
Note that the adjustment of the slurry is not specified in the above example, the binder and the solvent may use other substances, do not specify the mixing amount, and do not specify the doctor blade gap. . When a flat membrane and a support-integrated electrolyte were prepared, one green sheet and four cut-out sheets were used as green sheets in this embodiment. For example, two flat sheets and five cut-out sheets were stacked. Alternatively, the cutout may be performed according to the cell design. Of course, any pattern may be used for the firing temperature and the firing method. The electrode preparation is not specified.
[0095]
(Example 7)
This embodiment shows an embodiment in which a housing and a separator are actually assembled as a collective battery using a carbon material or stainless steel for a stable operation.
[0096]
First, an example in which stainless steel is first used for the housing and the separator will be described. FIG. 10 shows the configuration of the fuel cell manufactured in this example. BaZr having a diameter of 13 mm and a thickness of 220 μm was added to the solid electrolyte 16._0.4Ce_0.4In_0.2Al_0.02O_{3- α}In the figure, the anode on the upper surface side and the cathode on the lower surface side were formed using a platinum material. This was adhered to a ceramic base 17 holding this.
[0097]
In this bonding, an anode and a cathode are formed in the concave portion of the base 17 having four openings having a diameter of 9 mm and a circular concave portion for accommodating the solid electrolyte 16 having a diameter of 13.5 mm around the opening. The solid electrolyte 16 was housed, and the periphery thereof was bonded so that the anode and cathode faced the opening.
[0098]
Further, a cell is composed of a stainless steel current collector / separator 18 from above and below. In this embodiment, the current collector / separator 18 also serves as a housing.
[0099]
Stainless steel uses SUS304 and has a Cr content of 18%, Ni 8%, Fe 71%, and 3% of other elements. Its thermal expansion coefficient is 11 × 10^-6/ K, and the thermal expansion coefficients of the electrolyte and the ceramic substrate are also 10.5 × 10^-6/ K, 11 × 10^-6/ K. The total electrode area of this fuel cell is 2 cm²It is.
[0100]
While maintaining the temperature of the cell at 200 ° C., hydrogen and air were flowed at a flow rate of 50 cc / min to the anode and the cathode, respectively, as indicated by arrows, and a power generation test was performed. FIG. 11 shows the result that the assembled battery successfully generated power. It was found that the power generation characteristics of the assembled battery were equal to the total power generation of the single cells, and functioned as an assembled battery. The processing of SUS304 is easier and the cost is lower than that of oxide. Also, it has excellent durability.
[0101]
In this embodiment, BaZr is used as the electrolyte._0.4Ce_0.4In_0.2Al_0.02O_{3- α}Although the case where platinum was used for the electrode was shown, other proton conductive oxides may be used, and the electrode may not be made of platinum. Further, in this embodiment, an example in which SUS304 stainless steel is used for the current collector / separator is shown. However, the stainless steel may be SUS430, or a metal whose main component is an iron component having a chromium element of 18% or less, It may be a carbon material or a resin material. In the case where the current collector is formed of a resin material, a current collecting wiring may be provided. Further, a ceramic substrate is used as a substrate for holding the electrolyte, but any design and material may be used.
[0102]
The stainless steel preferably contains iron as a main component and contains 20% or less of a chromium element, and has a coefficient of thermal expansion of 9 to 15 × 10^-6/ K is preferred.
[0103]
(Example 8)
In this embodiment, an example in which a carbon material is used for a separator will be described. FIG. 12 shows a configuration of a three-cell stack fuel cell manufactured in this example. A 20 mm square, 280 μm thick BaZr is added to the solid electrolyte 19._0.6Ce_0.2Gd_0.2Al_0.02O_{3- α}The anode 20 and the cathode on the back side were formed using a platinum material. A separator 21 made of a carbon material is disposed above and below the cell to constitute an assembled battery. As the carbon material, G347 isotropic graphite made by Tokai Carbon is used. Thermal expansion coefficient is 4.2 × 10^-6/ K, and the resistance is 11 μΩm. The total electrode area of this fuel cell is 6.75 cm²It is. While keeping the temperature of the cell at 200 ° C., a power generation test was performed by flowing hydrogen and air at a flow rate of 50 cc / min to the anode 20 and the cathode, respectively. In addition, 21₁, 21₂Indicates an inlet and an outlet of hydrogen, respectively.₃, 21₄Indicates an air inlet and an exhaust gas outlet, respectively.
[0104]
FIG. 13 shows the result of good power generation of this assembled battery. The power generation characteristics of the collective battery were equal to the total power generation of the single cells, and it was found that the battery functioned as a collective battery. Further, the processing of carbon is easier and the cost is lower than that of oxide. Also, it has excellent durability.
[0105]
In this embodiment, a 20 mm square, 280 μm thick BaZr_{0. 6}Ce_0.2Gd_0.2Al_0.02O_{3- α}Although an example using platinum as the electrode has been described, other proton conductive oxides may be used, of course, the electrode may not be made of platinum, and the shape and size are not specified. Further, in this embodiment, an example in which G347 isotropic graphite material manufactured by Tokai Carbon Co., Ltd. is used for the separator is shown, but the carbon material may be G348 or SiC coating, and the main component is formed of graphite. Anything is acceptable. Further, instead of the carbon material, a metal such as stainless steel or a resin material may be used. Of course, the shape and size are not specified.
[0106]
FIG. 14 is a schematic diagram of a housing housing the assembled battery of FIG. In the figure, 25 is a main body housing made of a resin material, 26 is a gas supply part made of a metal material, and 27 is a current collector (current collecting housing) made of a metal material.
[0107]
(Other Examples)
The output of the fuel cell increases as the ionic conductivity (S / cm) of the electrolyte membrane increases and as the film thickness (cm) decreases. As a numerical value taking this into account, the sheet resistivity (Ωcm²). The battery output increases as the sheet resistivity decreases. The sheet resistivity is given by the following equation.
[0108]

In this embodiment, 0.001 mW / cm²Is the lower limit value of battery power generation, and the area resistivity at this time (about 10,000 Ωcm²), The electrolyte membrane was evaluated in three stages: good material 、, applicable material 、, and difficult to apply material x. Table 3 shows the results. Table 3 shows the minimum sheet resistivity at room temperature.
[0109]
[Table 3]

The electrolyte material of the present invention was evaluated as a good material ま た は or an applicable material ○.
[0110]
【The invention's effect】
As described above, according to the present invention, in a water-free solid oxide fuel cell without evaporation, diffusion, or leakage of a solution, the mechanical strength is excellent, and at a low temperature up to around room temperature of less than 500 ° C, Battery output can be obtained.
[0111]
Further, in the solid oxide fuel cell of the present invention, the solid electrolyte is supported by the support structure made of a resin material, so that the mechanical strength of the solid electrolyte membrane can be reinforced.
[0112]
In the solid oxide fuel cell of the present invention, at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. Workability is better than ceramics and the like, and cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of a solid oxide fuel cell according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of power generation characteristics in the present embodiment.
FIG. 3 is a view showing a bending strength test in this example.
FIG. 4 is a diagram showing an example of electrolyte reinforcement by a resin in the present embodiment.
FIG. 5 is a view showing an example of a fuel cell unit in which electrolyte is reinforced by a resin in the present embodiment.
FIG. 6 is a diagram showing power generation characteristics in the present embodiment.
FIG. 7 is a cross-sectional view of a battery cell in the present embodiment.
FIG. 8 is a cross-sectional view of a battery cell in the present embodiment.
FIG. 9 is a cross-sectional view of the battery cell in the present embodiment.
FIG. 10 is an exploded perspective view of the assembled battery.
11 is a diagram showing the power generation characteristics of FIG.
FIG. 12 is an exploded perspective view of another assembled battery.
FIG. 13 is a diagram showing the power generation characteristics of FIG.
FIG. 14 is a schematic configuration diagram of an assembled battery including a housing.
[Explanation of symbols]
1,4 sample
2,7 electrolyte membrane
3,6 epoxy resin frame
5 Battery cell
8,15 platinum electrode
9 porous electrode
10 carbon black electrode
12 Dense membrane porous integrated electrolyte
13 platinum carbon electrode
14 flat membrane support integrated electrolyte

Claims (31)

In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y Al z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In , 1>x> 0, 0.3>y> 0, 0.04>z> 0, 1.5>α> 0). In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaCe 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaZr 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y Al z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In , 1>x> 0, 0.3>y> 0, 0.04>z> 0, 1.5>α> 0), and supports the solid electrolyte. The solid oxide fuel cell in which the supporting structure is made of a resin material. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaCe 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), wherein the supporting structure for supporting the solid electrolyte is a solid electrolyte fuel made of a resin material. battery. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaZr 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), wherein the supporting structure for supporting the solid electrolyte is a solid electrolyte fuel made of a resin material. battery. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and an In, 1 >X> 0, 0.3>y> 0, 1.5>α> 0), and the supporting structure supporting the solid electrolyte is made of a resin material. Solid oxide fuel cell. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaCe 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0), wherein the solid oxide fuel cell has a composition represented by the following formula: wherein the support structure for supporting the solid electrolyte is made of a resin material. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The solid _{electrolyte, BaZr 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0), wherein the solid oxide fuel cell has a composition represented by the following formula: wherein the support structure for supporting the solid electrolyte is made of a resin material. The solid oxide fuel cell according to any one of claims 4 to 9,
A solid oxide fuel cell wherein the M of the composition of the oxide proton conductor comprises one or more elements selected from the group consisting of In, Gd, Y and Yb. The solid oxide fuel cell according to any one of claims 4 to 9,
A solid oxide fuel cell, wherein the electrodes are made of platinum-supported carbon. The solid oxide fuel cell according to any one of claims 4 to 9,
A solid oxide fuel cell, wherein the electrode is a mixture of particulate platinum and a material having the same components as the oxide proton conductor. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
A solid electrolyte fuel cell in which the solid electrolyte is a proton conductor, one of the pair of electrodes is an electrode containing platinum as a main component, and the other is a porous electrode made of a porous body carrying platinum; . In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
The electrode is an electrode containing platinum as a main component, the solid electrolyte is an oxide proton conductor, and a solid electrolyte having an integral structure of a membrane and a support structure that supports the membrane. Type fuel cell. In a solid oxide fuel cell comprising a pair of electrodes, a solid electrolyte is provided between the electrodes,
A solid electrolyte fuel cell, wherein the solid electrolyte is an oxide proton conductor and is an integrated structure of a dense sintered body and a porous sintered body. The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y Al z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In , 1>x> 0, 0.3>y> 0, 0.04>z> 0, 1.5>α> 0). The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, BaCe 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, BaZr 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and an In, 1 >X> 0, 0.3>y> 0, 1.5>α> 0). A solid oxide fuel cell which is an oxide proton conductor having a composition represented by the following formula: The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, BaCe 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: The solid oxide fuel cell according to any one of claims 13 to 15,
The solid _{electrolyte, BaZr 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0), which is an oxide proton conductor having a composition represented by the following formula: A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y Al z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In , 1>x> 0, 0.3>y> 0, 0.04>z> 0, 1.5>α> 0).
A solid oxide fuel cell, wherein at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, BaCe 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0), wherein at least one of the separator, the current collector and the housing is made of a resin A solid oxide fuel cell comprising at least one of a material, a carbon material, and a metal material. A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, BaZr 1-y M y Al} z O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0 , 0.04>z> 0, 1.5>α> 0).
A solid oxide fuel cell, wherein at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, Ba (Zr 1-x Ce} x) 1-y M y O 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and an In, 1 >X> 0, 0.3>y> 0, 1.5>α> 0).
A solid oxide fuel cell, wherein at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, BaCe 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0) is an oxide proton conductor having a composition represented by the following formula:
A solid oxide fuel cell, wherein at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. A solid electrolyte fuel cell including a pair of electrodes, a cell including a solid electrolyte provided between the electrodes and a separator disposed on both sides of the electrodes, and a housing surrounding the cells with a current collector.
The solid _{electrolyte, BaZr 1-y M y O} 3- α, (M is one or more elements selected from the group of trivalent rare earth elements and In, 0.3>y> 0,1 0.5>α> 0) is an oxide proton conductor having a composition represented by the following formula:
A solid oxide fuel cell, wherein at least one of the separator, the current collector, and the housing is made of at least one of a resin material, a carbon material, and a metal material. The solid oxide fuel cell according to any one of claims 22 to 27,
A solid oxide fuel cell, wherein the metal material is stainless steel, the main component of which is iron and the chromium element of 20% or less. The solid oxide fuel cell according to any one of claims 22 to 27,
A solid oxide fuel cell, wherein the metal material is stainless steel and has a coefficient of thermal expansion of 9 × 10 ⁻⁶ to 15 × 10 ⁻⁶ / K. A pair of electrodes, a solid electrolyte is provided between the electrodes, the electrode is an electrode containing platinum as a main component, the solid electrolyte is an oxide proton conductor, and a membrane, A method for manufacturing a solid oxide fuel cell having an integrated structure with a support structure that supports
A method for manufacturing a solid oxide fuel cell, wherein at least two or more sheets of electrolyte slurry are overlapped and co-sintered to form the integrated structure. A solid electrolyte type fuel comprising a pair of electrodes, wherein a solid electrolyte is provided between the electrodes, and the solid electrolyte is an oxide proton conductor, and is an integrated structure of a dense sintered body and a porous sintered body. A method for manufacturing a battery, comprising:
A sheet of dense and porous electrolyte slurry with different amounts of the organic binder is prepared, and at least two or more of the sheets are stacked and co-sintered to integrate the dense sintered body and the porous sintered body. A method for manufacturing a solid oxide fuel cell having a structure.

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