JP2004178934A

JP2004178934A - Container for fuel cell and fuel cell

Info

Publication number: JP2004178934A
Application number: JP2002342863A
Authority: JP
Inventors: Takayuki Miyao; 貴幸宮尾
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2002-11-26
Filing date: 2002-11-26
Publication date: 2004-06-24
Anticipated expiration: 2022-11-26
Also published as: JP3894878B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small, stout and reliable container for a fuel cell capable of storing electrolyte member, and capable of realizing a uniform distribution of gas, equalization of temperature gradient in the container and electric connection with high efficiency, and to provide a fuel cell used for a portable electronic device. <P>SOLUTION: The fuel cell 1 and the container for the fuel cell 2 comprise a base body 6 having a plurality of concave parts housing an electrolyte member having first and second electrodes 4, 5; a first fluid flow path 8 formed over a bottom surface of the concave part and an external surface of the base body 6; a first wiring conductor 10 of which one end is arranged at the bottom surface of the concave part and the other end is led out toward the outer surface of the base body 6; a lid body 7 fixed to the periphery of the concave part; a second fluid flow path 9 formed over an underside and the outer surface of the lid body 7; a second wiring conductor 11 of which one end is arranged at the underside of the lid body 7 and the other end is led out toward the outer surface of the lid body 7; and a third wiring conductor 12 of which one and the other ends face one and the other first electrodes of the electrolyte members 3. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、電解質部材を収容可能なセラミックスから成る小型で高信頼性の燃料電池用容器およびそれを用いた燃料電池に関するものである。
【０００２】
【従来の技術】
近年、これまでよりも低温で動作する小型燃料電池の開発が活発になされている。燃料電池には、これに用いる電解質の種類により、固体高分子電解質型燃料電池（ＰｏｌｙｍｅｒＥｌｅｃｔｒｏｌｙｔｅＦｕｅｌＣｅｌｌ：以下、ＰＥＦＣと記す）やリン酸型燃料電池、あるいは固体電解質型燃料電池といったものが知られている。
【０００３】
中でもＰＥＦＣは、作動温度が８０〜１００℃程度という低温であり、
（１）出力密度が高く、小型化・軽量化が可能である、
（２）電解質が腐食性でなく、しかも作動温度が低いため、耐食性の面から電池構成材料の制約が少ないので、コスト低減が容易である、
（３）常温で起動できるため、起動時間が短い、
といった優れた特長を有している。このためＰＥＦＣは、以上のような特長を活かして、車両用の駆動電源や家庭用のコジェネレーションシステム等への適用ばかりでなく、携帯電話・ＰＤＡ（ＰｅｒｓｏｎａｌＤｉｇｉｔａｌＡｓｓｉｓｔａｎｔｓ）・ノートパソコン・デジタルカメラやビデオ等の出力が数Ｗ〜数十Ｗの携帯電子機器用の電源としての用途が考えられてきている。
【０００４】
ＰＥＦＣは、大別して、例えば、白金や白金−ルテニウム等の触媒微粒子が付着した炭素電極から成る燃料極（アノード）と、白金等の触媒微粒子が付着した炭素電極から成る空気極（カソード）と、燃料極と空気極との間に介装されたフィルム状の電解質部材（以下、電解質部材と記す）とを有して構成されている。ここで、燃料極には、改質部を介して抽出された水素ガス（Ｈ_２）が供給され、一方、空気極には、大気中の酸素ガス（Ｏ_２）が供給されることにより、電気化学反応により所定の電気エネルギーが生成（発電）され、負荷に対する駆動電源（電圧／電流）となる電気エネルギーが生成される。
【０００５】
具体的には、燃料極に水素ガス（Ｈ_２）が供給されると、次の化学反応式（１）に示すように、上記触媒により電子（ｅ⁻）が分離した水素イオン（プロトン；Ｈ^＋）が発生し、電解質部材を介して空気極側に通過するとともに、燃料極を構成する炭素電極により電子（ｅ⁻）が取り出されて負荷に供給される。
３Ｈ_２ → ６Ｈ^＋＋６ｅ⁻ ・・・（１）
一方、空気極に空気が供給されると、次の化学反応式（２）に示すように、上記触媒により負荷を経由した電子（ｅ⁻）と電解質部材を通過した水素イオン（Ｈ^＋）と空気中の酸素ガス（Ｏ_２）とが反応して水（Ｈ_２Ｏ）が生成される。
６Ｈ^＋＋３／２Ｏ_２＋６ｅ⁻ → ３Ｈ_２Ｏ・・・（２）
このような一連の電気化学反応（式（１）および式（２））は、概ね８０〜１００℃の比較的低温の温度条件で進行し、電力以外の副生成物は基本的に水（Ｈ_２Ｏ）のみとなる。
【０００６】
電解質部材を構成するイオン導電膜（交換膜）は、スルホン酸基を持つポリスチレン系の陽イオン交換膜、フルオロカーボンスルホン酸とポリビニリデンフルオライドとの混合膜、フルオロカーボンマトリックスにトリフルオロエチレンをグラフト化したもの等が知られており、最近ではパーフルオロカーボンスルホン酸膜（例えばナフィオン：商品名、デュポン社製）等が用いられている。
【０００７】
図３に、従来の燃料電池（ＰＥＦＣ）の構成を断面図で示す。同図において、２１はＰＥＦＣ、２３は電解質部材、２４および２５は電解質部材を挟持するように電解質部材２３上に配置され、ガス拡散層および触媒層としての機能を有する一対の多孔質電極、すなわち燃料極および空気極であり、２６はガスセパレータ、２８は燃料流路、２９は空気流路である。
【０００８】
ガスセパレータ２６は、ガスセパレータ２６の外形を形成する積層部およびガス流入出枠と、燃料流路２８と空気流路２９とを分離するセパレータ部と、このセパレータ部を貫通するように設けられた、電解質部材２３の燃料極２４および空気極２５に対応するように配置された電極とから構成されている。電解質部材２３の燃料極２４、空気極２５が電気的に直列および／または並列に接続されるようにガスセパレータ２６を介して多数積層して電池の最小単位である燃料電池スタックとし、この燃料電池スタックを、箱体に収納したものが一般的なＰＥＦＣ本体である。
【０００９】
ガスセパレータ２６に形成された燃料流路２８を通して燃料極２４には改質器から水蒸気を含む燃料ガス（水素に富むガス）が供給され、また、空気極２５には空気流路２９を通して大気中から酸化剤ガスとして空気が供給され、電解質部材２３での化学反応により発電される。
【００１０】
【特許文献１】
特開２００１−２６６９１０号公報
【特許文献２】
特表２００１−５０７５０１号公報
【００１１】
【発明が解決しようとする課題】
しかしながら、このような高電圧・高容量の電池として従来より提案され開発されている燃料電池２１は、スタック構造を有し構成要素が大面積化された大重量で大型の電池であり、小型電池としての燃料電池の利用は、従来はほとんど考えられていなかった。
【００１２】
すなわち、このような燃料電池２１における従来のガスセパレータ２６には、これを用いて電解質部材２３を積層した積層体において、電解質部材２３の側面が外部に露出していることによって、携帯時の落下等により損傷を受けやすく、燃料電池２１全体の機械的信頼性を確保し難いという問題点があった。
【００１３】
また、携帯電子機器に燃料電池２１を搭載するためには、従来の大型燃料とは異なった、コンパクト性・簡便性・安全性に優れる燃料電池用容器が必要になる。すなわち、汎用の化学電池のようなポータブル電源として適用するためには、作動温度までの温度上昇を短時間化するために、また熱容量を小さくするために、燃料電池用容器を小型化・低背化する必要があるが、従来の燃料電池２１では熱容量の割合の大部分を占めるガスセパレータ２６は、特にカーボン板の表面に切削加工で流路形成されるガスセパレータ２６の場合など、薄肉化すると脆くなるため、数ｍｍの厚みが必要である。このため、小型化・低背化が困難であるという問題点もあった。
【００１４】
さらに、燃料電池２１の出力電圧は、電解質部材２３の表裏面の各電極２４・２５に供給されるガスの分圧によって決まる。すなわち、電解質部材２３に供給された燃料ガスがガス流路２８を進んで発電反応において消費されると、燃料極２４の面上の燃料ガスの分圧が下がって出力電圧が下がる。これと同様に、空気も空気流路２９を進んで消費されると、空気極２５の面上の酸素の分圧が下がって出力電圧が下がる。従って、燃料ガスを均等に供給する必要があるが、従来の燃料電池２１のガスセパレータ２６は、特にカーボン板の表面に切削加工により流路を形成していることから、薄型化したときには流路の溝が狭くなるため、流路抵抗が大きくなり、均一なガス供給が困難であるという問題点もあった。
【００１５】
また、複数の電解質部材２３とその対向する燃料極２４・空気極２５とガスセパレータ２６との組み合わせが、任意に効率よく直列接続または並列接続されて、全体の出力電圧および出力電流が調整されるようにする必要があるが、従来の燃料電池２１では電解質部材２３を挟む燃料極および空気極から電気を取り出すためには、外部に引き出し接続する方法か、もしくはガスセパレータ２６を導電性材料として重ね合わせ直列接続する方法しかなく、小型燃料電池においてはそれが困難であるという問題点もあった。
【００１６】
本発明は以上のような従来の技術の問題点に鑑み完成されたものであり、その目的は、電解質部材を収納可能な、小型で、堅牢な燃料電池用容器であり、また、ガスの均等供給・燃料電池容器内の温度勾配の均一化・高効率な電気接続を図ることができる信頼性のある燃料電池用容器およびそれを用いた燃料電池を提供することにある。
【００１７】
【課題を解決するための手段】
本発明の第１の燃料電池用容器は、下側および上側主面にそれぞれ第１および第２電極を有する電解質部材を複数個収容する凹部を上面に有するセラミックスから成る基体と、前記電解質部材の前記下側主面に対向する前記凹部の底面から前記基体の外面にかけて形成された第１流体流路と、前記電解質部材の前記第１電極に対向する前記凹部の底面に一端が配設され、他端が前記基体の外面に導出された第１配線導体と、前記基体の前記凹部の周囲の上面に前記凹部を覆って取着される、前記凹部を気密に封止する蓋体と、前記電解質部材の前記上側主面に対向する前記蓋体の下面から前記蓋体の外面にかけて形成された第２流体流路と、前記電解質部材の前記第２電極に対向する前記蓋体の前記蓋体の下面に一端が配設され、他端が前記蓋体の外面に導出された第２配線導体と、前記基体に形成され、一端が前記凹部の底面で前記電解質部材の１つの前記第１電極に対向するとともに、他端が前記凹部の底面で前記電解質部材の他の１つの前記第１電極に対向する第３配線導体とを具備することを特徴とするものである。
【００１８】
また、本発明の第２の燃料電池用容器は、下側および上側主面にそれぞれ第１および第２電極を有する電解質部材を複数個収容する凹部を上面に有するセラミックスから成る基体と、前記電解質部材の前記下側主面に対向する前記凹部の底面から前記基体の外面にかけて形成された第１流体流路と、前記電解質部材の前記第１電極に対向する前記凹部の底面に一端が配設され、他端が前記基体の外面にかけて形成された第１配線導体と、前記基体の前記凹部の周囲の上面に前記凹部を覆って取着される、前記凹部を気密に封止する蓋体と、前記電解質部材の前記上側主面に対向する前記蓋体の下面から前記蓋体の外面にかけて形成された第２流体流路と、前記電解質部材の前記第２電極に対向する前記蓋体の下面に一端が配設され、他端が前記蓋体の外面に導出された第２配線導体と、一端が前記凹部の底面で前記電解質部材の１つの前記第１電極に対向するとともに、他端が前記基体の前記蓋体が取着される上面に導出された第４配線導体と、一端が前記蓋体の下面で前記電解質部材の他の１つの前記第２電極に対向するとともに、他端が前記蓋体の前記基体の前記上面に取得される下面に前記第４配線導体の他端と対向するように導出された第５配線導体とを具備することを特徴とするものである。
【００１９】
また、本発明の第１の燃料電池は、上記構造の本発明の第１の燃料電池用容器の前記凹部に複数個の電解質部材を収容して、この電解質部材の前記下側および上側主面を前記第１および第２流体流路との間でそれぞれ流体のやりとり可能なように配置するとともに、前記第１および第２配線導体を前記第１および第２電極に、ならびに前記第３配線導体を前記第１電極にそれぞれ電気的に接続し、前記基体の前記凹部の周囲の上面に前記凹部を覆って前記蓋体を取着して成ることを特徴とするものである。
【００２０】
また、本発明の第２の燃料電池は、上記構成の本発明の第２の燃料電池用容器の前記凹部に複数個の電解質部材を収容して、この電解質部材の前記下側および上側主面を前記第１および第２流体流路との間でそれぞれの流体がやりとり可能なように配置するとともに、前記第１および第２配線導体を前記第１および第２電極に、ならびに前記第４および第５配線導体を前記第１および第２電極にそれぞれ電気的に接続し、前記基体の前記凹部の周囲の上面に前記凹部を覆うとともに前記第４および第５配線導体の前記他端同士を接続して前記蓋体を取着して成ることを特徴とするものである。
【００２１】
本発明の第１および第２の燃料電池用容器によれば、下側および上側主面にそれぞれ第１および第２電極を有する電解質部材を複数個収容する凹部を上面に有するセラミックスから成る基体と、この基体の凹部の周囲の上面に凹部を覆って取着される、凹部を気密に封止する蓋体とを具備していることから、燃料電池用容器内を気密に封止することで、気体等の流体の漏れがなく、この容器の他にパッケージ等の容器を設ける必要がないので、効率良く動作させることができる燃料電池を得ることができるとともに、小型化にも有効なものとなる。また、凹部を上面に有するセラミックスから成る基体とこの凹部を封止する蓋体とで形成される箱体内に複数の電解質部材を収納して燃料電池とすることができるので、電解質部材が容器の外部に露出して損傷を受けたりすることがなく、燃料電池全体としての機械的信頼性が向上する。また、凹部および蓋体で構成される容器内部に一端が配設された第１〜第３配線導体、または第１，第２，第４および第５配線導体の他には電解質部材自体に無用な電気的接触をしないで済むので、信頼性および安全性の高い燃料電池を得ることができる。さらに、燃料電池用容器の構成材料としてセラミックスを用いたことにより、各種のガスを始めとする流体に対する耐食性に優れる燃料電池を得ることができる。
【００２２】
また、電解質部材の下側主面に対向する凹部の底面から基体の外面にかけて形成された第１流体流路と、電解質部材の上側主面に対向する蓋体の下面から蓋体の外面にかけて形成された第２流体流路とを具備していることから、複数のそれぞれの流体流路は、電解質部材を挟んで、それぞれ対向する内壁面に設けられているため、電解質部材へ供給される流体の均一供給性を向上させることができる。このような流体経路によれば、流体が電解質部材に対して垂直に流れるため、例えば、流体が水素ガスと空気（酸素）ガスとの場合に、電解質部材が下側および上側主面にそれぞれ有する第１および第２電極に供給される各ガス分圧が下がることはなく、所定の安定した出力電圧を得ることができるという効果がある。さらに、供給される流体の圧力、例えばガス分圧が安定するため、燃料電池用容器の内部温度の分布が均一化され、その結果、電解質部材に生じる熱応力を抑制することができ、燃料電池の信頼性を向上させることができる。さらにまた、それぞれの流体流路は基体と蓋体とに形成されるため、各流路の密閉性に優れ、本来は流路的に隔絶されるべき２種類の原料流体（例えば酸素ガスと水素ガスもしくはメタノール等）が混合してしまうことによって燃料電池としての機能が発現されなくなるようなことがなく、また、可燃性の流体が高温で混合された後に引火・爆発を起こす危険性もないので、安全な燃料電池を提供することができる。
【００２３】
さらに、本発明の第１の燃料電池用容器によれば、基体に形成された、一端が凹部の底面で電解質部材の１つの第１電極に対向するとともに、他端が凹部の底面で電解質部材の他の１つの第１電極に対向する第３配線導体とを具備していることから、複数個の電解質部材を電気的に接続することでそれらを並列接続することが可能となる。その結果、燃料電池全体の出力電流の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことができる。
【００２４】
さらにまた、本発明の第２の燃料電池用容器によれば、複数個の電解質部材を収容する凹部を有する基体およびこれに取着される蓋体に形成された、一端が凹部の底面で電気電解部材の１つの第１電極に対向するとともに、他端が基体の上面の蓋体が取着される部位に導出された第４配線導体と、一端が蓋体の下面で電解質部材の他の１つの第２電極に対向するとともに、他端が蓋体の下面の基体の上面に取着される部位に第４配線導体の他端と対向するように導出された第５配線導体とを具備していることから、複数個の電解質部材を電気的に接続することでそれらを直列接続することが可能となる。その結果、一つ一つの電解質部材の発電では微小電圧であっても、直列接続により合計の電圧の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことが可能となる。
【００２５】
また、本発明の第１および第２の燃料電池によれば、本発明の第１および第２の燃料電池用容器の凹部に電解質部材を収容して、この電解質部材の下側および上側主面を第１および第２流体流路との間でそれぞれの流体がやりとり可能なように配置するとともに、第１および第２電極を第１〜第３配線導体、ならびに第１，第２，第４および第５配線導体にそれぞれ電気的に接続し、基体の凹部の周囲の上面に凹部を覆って蓋体を取着して成ることから、以上のような本発明の第１および第２の燃料電池用容器による特長を備えた、小型・堅牢で、ガスの均等供給・燃料電池容器内の温度勾配の均一化・高効率な電気接続を図ることができる信頼性のある燃料電池を得ることができるとともに、複数個の電解質部材を並列接続することにより燃料電池全体の出力電流の調整ができるため、あるいは複数個の電解質部材を直列接続することにより合計の電圧の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことができる。
【００２６】
従って、本発明の燃料電池用容器および燃料電池によれば、コンパクト性・簡便性・安全性に優れ、流体の均等供給・高効率な電気接続により、長期にわたり安定して作動させることができる燃料電池を提供することができる。
【００２７】
【発明の実施の形態】
次に、本発明を添付図面に基づき詳細に説明する。
【００２８】
図１は本発明の第１の燃料電池用容器およびそれを用いた第１の燃料電池について実施の形態の一例を示す断面図である。図１において、１は燃料電池、２は燃料電池用容器、３は電解質部材、４は第１電極、５は第２電極、６は基体、７は蓋体、８は第１流体流路、９は第２流体流路、１０は第１配線導体、１１は第２配線導体、１２は第３配線導体である。
【００２９】
電解質部材３は、例えばイオン導電膜（交換膜）の両主面上に、下側主面に形成された第１電極４および上側主面に形成された第２電極５にそれぞれ対向するように、アノード側電極となる燃料極（図示せず）と、カソード側電極となる空気極（図示せず）とが一体的に形成されている。そして、電解質部材３で発電された電流を第１電極４，第２電極５へ流し、外部へ取り出すことができるものとなっている。
【００３０】
このような電解質部材３のイオン導電膜（交換膜）は、パーフルオロカーボンスルフォン酸樹脂、例えばナフィオン（商品名、デュポン社製）等のプロトン伝導性のイオン交換樹脂により構成されている。また、燃料極および空気極は、多孔質状態のガス拡散電極であり、多孔質触媒層とガス拡散層の両方の機能を兼ね備えるものである。これらの燃料極および空気極は、白金・パラジウムあるいはこれらの合金等の触媒を担持した導電性微粒子、例えばカーボン微粒子をポリテトラフルオロエチレンのような疎水性樹脂結合剤により保持した多孔質体によって構成されている。
【００３１】
電解質部材３の下側主面の第１電極４および上側主面の第２電極５は、白金や白金−ルテニウム等の触媒微粒子の付いた炭素電極を電解質部材３上にホットプレスする方法、または、白金や白金−ルテニウム等の触媒微粒子の付いた炭素電極材料と電解質材料を分散した溶液との混合物を電解質上に塗布または転写する方法等により形成される。
【００３２】
燃料電池用容器２は、凹部を有する基体６と蓋体７とから成り、電解質部材３を凹部の内部に搭載して気密に封止する役割を持ち、酸化アルミニウム（Ａｌ_２Ｏ_３）質焼結体，ムライト（３Ａｌ_２Ｏ_３・２ＳｉＯ_２）質焼結体，炭化珪素（ＳｉＣ）質焼結体，窒化アルミニウム（ＡｌＮ）質焼結体，窒化珪素（Ｓｉ_３Ｎ_４）質焼結体，ガラスセラミックス焼結体等のセラミックス材料で形成されている。
【００３３】
なお、ガラスセラミックス焼結体はガラス成分とフィラー成分とから成るが、ガラス成分としては、例えばＳｉＯ_２−Ｂ_２Ｏ_３系，ＳｉＯ_２−Ｂ_２Ｏ_３−Ａｌ_２Ｏ_３系，ＳｉＯ_２−Ｂ_２Ｏ_３−Ａｌ_２Ｏ_３−ＭＯ系（但し、ＭはＣａ，Ｓｒ，Ｍｇ，ＢａまたはＺｎを示す），ＳｉＯ_２−Ａｌ_２Ｏ_３−Ｍ^１Ｏ−Ｍ^２Ｏ系（但し、Ｍ^１およびＭ^２は同一または異なってＣａ，Ｓｒ，Ｍｇ，ＢａまたはＺｎを示す），ＳｉＯ_２−Ｂ_２Ｏ_３−Ａｌ_２Ｏ_３−Ｍ^１Ｏ−Ｍ^２Ｏ系（但し、Ｍ^１およびＭ^２は前記と同じである），ＳｉＯ_２−Ｂ_２Ｏ_３−Ｍ^３ _２Ｏ系（但し、Ｍ^３はＬｉ，ＮａまたはＫを示す），ＳｉＯ_２−Ｂ_２Ｏ_３−Ａｌ_２Ｏ_３−Ｍ^３ _２Ｏ系（但し、Ｍ^３は前記と同じである），Ｐｂ系ガラス，Ｂｉ系ガラス等が挙げられる。
【００３４】
また、フィラー成分としては、例えばＡｌ_２Ｏ_３，ＳｉＯ_２，ＺｒＯ_２とアルカリ土類金属酸化物との複合酸化物、ＴｉＯ_２とアルカリ土類金属酸化物との複合酸化物、Ａｌ_２Ｏ_３およびＳｉＯ_２から選ばれる少なくとも１種を含む複合酸化物（例えばスピネル，ムライト，コージェライト）等が挙げられる。
【００３５】
燃料電池用容器２は、凹部を有する基体６と蓋体７とから成り、基体６の凹部の周囲に凹部を覆って蓋体７を取着することによって凹部を気密に封止するため、半田や銀ろう等の金属接合材料での接合、エポキシ等の樹脂材料での接合、凹部の周囲の上面に鉄合金等で作られたシールリング等を接合してシームウェルドやエレクトロンビームやレーザ等で溶接する方法等によって、蓋体７が基体６に取着される。なお、蓋体７にも基体６と同様の凹部を形成しておいてもよい。
【００３６】
基体６および蓋体７は、それぞれ厚みを薄くし、燃料電池１の低背化を可能とするためには、機械的強度である曲げ強度が２００ＭＰａ以上であることが好ましい。
【００３７】
基体６および蓋体７は、例えば相対密度が９５％以上の緻密質からなる酸化アルミニウム質焼結体で形成されていることが好ましい。その場合であれば、例えば、まず酸化アルミニウム粉末に希土類酸化物粉末や焼結助剤を添加・混合して、酸化アルミニウム質焼結体の原料粉末を調整する。次いで、この酸化アルミニウム質焼結体の原料粉末に有機バインダおよび分散媒を添加・混合してペースト化し、このペーストからドクターブレード法によって、あるいは原料粉末に有機バインダを加え、プレス成形，圧延成形等によって、所定の厚みのグリーンシートを作製する。そして、このグリーンシートに対して、金型による打ち抜き・マイクロドリル・レーザ等により、第１流体流路８および第２流体流路９としての貫通穴、ならびに第１配線導体１０，第２配線導体１１および第３配線導体１２を配設するための貫通孔を形成する。
【００３８】
第１配線導体１０，第２配線導体１１および第３配線導体１２は、酸化を防ぐために、タングステンおよび／またはモリブデンで形成されているのが好ましい。その場合であれば、例えば、無機成分としてタングステンおよび／またはモリブデン粉末１００質量部に対して、Ａｌ_２Ｏ_３を３〜２０質量部，Ｎｂ_２Ｏ_５を０．５〜５質量部の割合で添加してなる導体ペーストを調製する。この導体ペーストをグリーンシートの貫通孔内に充填して、貫通導体としてのヴィア導体を形成する。
【００３９】
これらの導体ペースト中には、基体６や蓋体７のセラミックスとの密着性を高めるために、酸化アルミニウム粉末や、基体６や蓋体７を形成するセラミックス成分と同一の組成物粉末を、例えば０．０５〜２体積％の割合で添加することも可能である。
【００４０】
なお、基体６や蓋体７の表層および内層への第１配線導体１０、第２配線導体１１および第３配線導体１２の形成は、貫通孔へ導体ペーストを充填してヴィア導体を形成する前後あるいはそれと同時に、同様の導体ペーストをグリーンシートに対しスクリーン印刷，グラヴィア印刷等の方法で所定パターンに印刷塗布して形成する。
【００４１】
その後、導体ペーストを印刷し充填した所定枚数のシート状成形体を位置合わせして積層圧着した後、この積層体を、例えば非酸化性雰囲気中にて、焼成最高温度が１２００〜１５００℃の温度で焼成して、目的とするセラミックスの基体６や蓋体７および第１配線導体１０，第２配線導体１１，第３配線導体１２を得る。
【００４２】
また、セラミックスから成る基体６や蓋体７は、その厚みを０．２ｍｍ以上とすることが好ましい。厚みが０．２ｍｍ未満では、強度が不足しがちなため、基体６に蓋体７を取着したときに発生する応力により、基体６および蓋体７に割れ等が発生しやすくなる傾向がある。他方、厚みが５ｍｍを超えると、薄型化・低背化が困難となるため、小型携帯機器に搭載する燃料電池としては不適切となり、また、熱容量が大きくなるため、電解質部材３の電気化学反応条件に相当する適切な温度にすばやく設定することが困難となる傾向がある。
【００４３】
第１配線導体１０，第２配線導体１１および第３配線導体１２は、それぞれ電解質部材３の第１電極４および第２電極５に電気的に接続されて、電解質部材３で発電された電流を燃料電池用容器２の外部へ取り出すための導電路として機能する。
【００４４】
第１配線導体１０は、基体６の凹部の底面の電解質部材３の第１電極４に対向する部位に一端が配設され、他端が基体６の外面に導出されて形成されている。このような第１配線導体１０は、前述のように基体６と一体的に形成されている。また、第１配線導体１０は、その両端を第１電極４に接触させやすいように基体６の凹部の底面より１０μｍ以上高くするように形成するのが望ましい。この高さを得るためには、前述したように導体ペーストを印刷塗布して形成する際に、塗布厚みを厚くするように印刷条件を設定すればよい。また、第１配線導体１０は第１電極４に対向させて複数配置し、第１配線導体１０による電気損失を減少させることが望ましく、第１配線導体１０の基体６の貫通部についてはφ５０μｍ以上の径とすることが好ましい。
【００４５】
また、第２配線導体１１は、蓋体７の下面の電解質部材３の第２電極５に対向する部位に一端が配設され、他端が蓋体７の外面に導出されて形成されている。このような第２配線導体１１も、第１配線導体１０と同様に、蓋体７と一体的に形成されている。また、第２配線導体１１は、その両端を第２電極５に接触させやすいように蓋体７の下面より１０μｍ以上高くするように形成するのが望ましい。この高さを得るためには、前述したように導体ペーストを印刷塗布して形成する際に、塗布厚みを厚くするように印刷条件を設定すればよい。また、第２配線導体１１は第２電極５に対向させて複数配置し、第２配線導体１１による電気損失を減少させることが望ましく、第２配線導体１１の蓋体７の貫通部についてはφ５０μｍ以上の径とすることが好ましい。
【００４６】
また、第３配線導体１２は、基体６の凹部の底面の電解質部材３の１つの第１電極４に対向する部位に一端が配設され、他端が同じ凹部の底面で電解質部材３の他の１つの第１電極４に対向する部位に配設されて基体６と一体的に形成されている。また、第３配線導体１２は、その両端を第１電極４に接触させやすいように基体６の凹部の底面より１０μｍ以上高くするように形成するのが望ましい。この高さを得るためには、前述したように導体ペーストを印刷塗布して形成する際に、塗布厚みを厚くするように印刷条件を設定すればよい。また、第３配線導体１２は第１電極４に対向させて複数配置し、第３配線導体１２による電気損失を減少させることが望ましく、第３配線導体１２の基体６の貫通部についてはφ５０μｍ以上の径とすることが好ましい。
【００４７】
これら第１配線導体１０，第２配線導体１１および第３配線導体１２には、その露出する表面にニッケルから成る良導電性で、かつ耐蝕性およびロウ材との濡れ性が良好な金属をメッキ法により被着させておくと、第１配線導体１０，第２配線導体１１および第３配線導体１２と、第１配線導体１０，第２配線導体１１および第３配線導体１２ならびに外部電気回路との電気的接続を良好とすることができる。従って、第１配線導体１０，第２配線導体１１および第３配線導体１２は、その露出する表面にニッケルから成る良導電性で、かつ耐蝕性およびロウ材との濡れ性が良好な金属をメッキ法により被着させておくことが好ましい。
【００４８】
そして、これら第１，第２および第３配線導体１０・１１・１２と第１および第２電極４・５との電気的な接続は、基体６と蓋体７とで電解質部材３を挟み込むことによって、第１，第２および第３配線導体１０・１１・１２と第１および第２電極４・５とを圧着接触させて電気的接続させる等の構成によって行なえばよい。
【００４９】
また、第１電極４および第２電極５に対向する基体６の凹部の底面および蓋体７の下面には、それぞれ第１流体流路８および第２流体流路９が配置されており、第１流体流路８は基体６の外面にかけて、また第２流体流路９は蓋体７の外面にかけて形成されている。これら第１および第２流体流路８・９は、それぞれ基体６や蓋体７に形成した貫通穴あるいは溝によって、燃料ガス例えば水素に富む改質ガス、あるいは酸化剤ガス例えば空気等の、電解質部材３へ供給される流体の通路として、あるいは反応で生成される水等の、反応後に電解質部材３から排出される流体の通路として設けられている。
【００５０】
第１流体流路８および第２流体流路９として基体６および蓋体７に形成される貫通穴あるいは溝は、電解質部材３に均等に燃料ガスや酸化剤ガス等の流体が供給されるように、燃料電池１の仕様に応じて、貫通穴の径や数、あるいは溝の幅，深さ，配置を決めればよい。
【００５１】
本発明の第１の燃料電池用容器２および第１の燃料電池１においては、第１流体流路８および第２流体流路９は、好適には、電解質部材３に均一な圧力で流体を流すため、φ０．１ｍｍ以上の穴径とし、間隔を一定にして配置するようにするとよい。
【００５２】
このように電解質部材３の第１電極４が形成された下側主面に対向させて第１流体流路８を、第２電極５が形成された上側主面に対向させて第２流体流路９を形成したことによって、電解質部材３の下側および上側主面と第１および第２流体流路８・９との間で流体がやりとり可能となり、その流体がそれぞれの流路を通して供給あるいは排出されることとなる。そして、例えば流体としてガスを供給する場合であれば、電解質部材３の第１電極４および第２電極５にそれぞれ供給されるガス分圧が下がることをなくすことができ、所定の安定した出力電圧を得ることができる。さらに、供給されるガス分圧が安定するため、燃料電池１の内部圧力が均一化され、その結果、電解質部材３に生じる熱応力を抑制することができるので、第１の燃料電池１の信頼性を向上させることができる。
【００５３】
以上の構成により、図１に示すような、電解質部材３を収納可能な、小型で堅牢な本発明の第１の燃料電池用容器２が得られ、高効率制御が可能な本発明の第１の燃料電池１が得られる。
【００５４】
次に図２は本発明の燃料電池用容器およびそれを用いた第２の燃料電池について実施の形態の一例を示す断面図であり、図３はその平面図である。これらの図において、１’は燃料電池、２’は燃料電池用容器、３は電解質部材、４は第１電極、５は第２電極、６は基体、７は蓋体、８は第１流体流路、９は第２流体流路、１０は第１配線導体、１１は第２配線導体、１３は第４配線導体、１４は第５配線導体である。
【００５５】
図２および図３の３から１１については図１と同様となる。第４配線導体１３は、基体６の凹部の底面で複数個の電解質部材３の１つの第１電極４に対向する部位に一端が配設され、他端が基体６の上面の蓋体７が取着される部位に導出されている。また、第５配線導体１４は、蓋体７の下面の複数個の電解質部材３の他の１つの第２電極５に対向する部位に一端が配設され、他端が蓋体７の下面の基体６の上面に取着される部位に第４配線導体１３の他端と対向するように導出されて形成されている。
【００５６】
このような第４配線導体１３は、第３配線導体１２と同様に、基体６と一体的に形成され、その一端を第１電極４に接触させやすいように基体６の凹部の底面より１０μｍ以上高くするように形成するのが望ましい。この高さを得るためには、前述したように導体ペーストを印刷塗布して形成する際に、塗布厚みを厚くするように印刷条件を設定すればよい。また、第４配線導体１３は第１電極４に対向させて複数配置し、第４配線導体１３による電気損失を減少させることが望ましく、第４配線導体１３の基体６の貫通部についてはφ５０μｍ以上の径とすることが好ましい。
【００５７】
また、第５配線導体１４も、第２配線導体１１と同様に、蓋体７と一体的に形成され、その一端を第２電極５に接触させやすいように蓋体７の下面より１０μｍ以上高くするように形成するのが望ましい。この高さを得るためには、前述したように導体ペーストを印刷塗布して形成する際に、塗布厚みを厚くするように印刷条件を設定すればよい。また、第５配線導体１４も第２電極５に対向させて複数配置し、第５配線導体１４による電気損失を減少させることが望ましく、第５配線導体１４の蓋体７の貫通部についてはφ５０μｍ以上の径とすることが好ましい。
【００５８】
図１，図２および図３に示すように、本発明の第１および第２の燃料電池用容器２・２’ならびに第１および第２の燃料電池１・１’によれば、基体６の凹部に複数個の電解質部材３を収容するとともに、第３配線導体１２、または第４配線導体１３および第５配線導体１４を配設し、複数の電解質部材３の第１電極４の間、または第１電極４と第２電極５との間を電気的に接続し、両端となる位置に配置された電解質部材３に全体としての出力を取り出すように第１配線導体１０および第２配線導体１１をそれぞれに電気的に接続することで、第１〜第３配線導体１０・１１・１２により、ならびに第１，第２，第４および第５配線導体１０・１１・１３・１４により３次元的に自由に配線ができるため、複数個の電解質部材３を任意に直列接続または並列接続することが可能となる。その結果、全体の出力電圧および出力電流を効率よく調整することが可能となるため、複数個の電解質部材３にて電気化学的に生成された電気を良好に外部に取り出すことができる燃料電池となる。
【００５９】
なお、本発明は以上の実施の形態の例に限定されるものではなく、本発明の要旨を逸脱しない範囲であれば、種々の変更を行なっても何ら差し支えない。例えば、第１流体流路や第２流体流路については、燃料電池全体を薄型化するため、基体または蓋体の側面からの流入口を設けるようにしてもよい。これによれば、特に携帯電子機器用として小型化を図る上で有効となる。さらに、第１および第２配線導体については、基体および蓋体の外面に導出される他端を、それぞれ同じ側の側面に引き出すように配設してもよい。これによれば、燃料電池の一方側面に配線や流路等をまとめることができ、小型化と外部への接合部の保護とが容易となり、信頼性の高い設計が可能となるとともに、長期間安定した作動が可能な燃料電池となる。
【００６０】
【発明の効果】
本発明の第１および第２の燃料電池用容器によれば、下側および上側主面にそれぞれ第１および第２電極を有する電解質部材を収容する凹部を上面に有するセラミックスから成る基体と、この基体の凹部の周囲の上面に凹部を覆って取着される、凹部を気密に封止する蓋体とを具備していることから、燃料電池用容器内を気密に封止することで、気体等の流体の漏れがなく、この容器の他にパッケージ等の容器を設ける必要がないので、効率良く動作させることができる燃料電池を得ることができるとともに、小型化にも有効なものとなる。また、凹部を上面に有するセラミックスから成る基体とこの凹部を封止する蓋体とで形成される箱体内に複数の電解質部材を収納して燃料電池とすることができるので、電解質部材が容器の外部に露出して損傷を受けたりすることがなく、燃料電池全体としての機械的信頼性が向上する。また、凹部および蓋体で構成される容器内部に一端が配設された第１〜第３配線導体、または第１，第２，第４および第５配線導体の他には電解質部材自体に無用な電気的接触をしないで済むので、信頼性および安全性の高い燃料電池を得ることができる。さらに、燃料電池用容器の構成材料としてセラミックスを用いたことにより、各種のガスを始めとする流体に対する耐食性に優れる燃料電池を得ることができる。
【００６１】
また、電解質部材の下側主面に対向する凹部の底面から基体の外面にかけて形成された第１流体流路と、電解質部材の上側主面に対向する蓋体の下面から蓋体の外面にかけて形成された第２流体流路とを具備していることから、複数のそれぞれの流体流路は、電解質部材を挟んで、それぞれ対向する内壁面に設けられているため、電解質部材へ供給される流体の均一供給性を向上させることができる。このような流体経路によれば、流体が電解質部材に対して垂直に流れるため、例えば、流体が水素ガスと空気（酸素）ガスとの場合に、電解質部材が下側および上側主面にそれぞれ有する第１および第２電極に供給される各ガス分圧が下がることはなく、所定の安定した出力電圧を得ることができるという効果がある。さらに、供給される流体の圧力、例えばガス分圧が安定するため、燃料電池用容器の内部温度の分布が均一化され、その結果、電解質部材に生じる熱応力を抑制することができ、燃料電池の信頼性を向上させることができる。さらにまた、それぞれの流体流路は基体と蓋体とに形成されるため、各流路の密閉性に優れ、本来は流路的に隔絶されるべき２種類の原料流体（例えば酸素ガスと水素ガスもしくはメタノール等）が混合してしまうことによって燃料電池としての機能が発現されなくなるようなことがなく、また、可燃性の流体が高温で混合された後に引火・爆発を起こす危険性もないので、安全な燃料電池を提供することができる。
【００６２】
また、本発明の第１および第２の燃料電池によれば、本発明の第１および第２の燃料電池用容器の凹部に電解質部材を収容して、この電解質部材の下側および上側主面を第１および第２流体流路との間でそれぞれの流体がやりとり可能なように配置するとともに、第１および第２電極を第１〜第３配線導体、ならびに第１，第２，第４および第５配線導体にそれぞれ電気的に接続し、基体の凹部の周囲の上面に凹部を覆って蓋体を取着して成ることから、電解質部材が露出して損傷を受けることがなく、また、凹部および蓋体で構成される容器内部に一端が配設された第１〜第３配線導体、ならびに第１，第２，第４および第５配線導体の他には電解質部材に無用な電気的接触をしないで済むので、信頼性および安全性の高い燃料電池を得ることができる。また、第１および第２流体流路は、電解質部材を挟んで、それぞれ対向する内壁面である基体の凹部の底面および蓋体の下面に設けられているため、電解質部材へ供給されるガスの均一供給性を向上させることができ、電解質部材の第１および第２電極に供給されるガス分圧が下がることをなくすことができるので、所定の安定した出力電圧を得ることができる。そして、電解質部材に生じる応力も抑制することができ、信頼性を向上させることができる。
【００６３】
さらに、本発明の第１の燃料電池用容器によれば、基体に形成された、一端が凹部の底面で電解質部材の１つの第１電極に対向するとともに、他端が凹部の底面で電解質部材の他の１つの第１電極に対向する第３配線導体とを具備していることから、複数個の電解質部材を電気的に接続することでそれらを並列接続することが可能となる。その結果、燃料電池全体の出力電流の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことができる。
【００６４】
さらにまた、本発明の第２の燃料電池用容器によれば、複数個の電解質部材を収容する凹部を有する基体およびこれに取着される蓋体に形成された、一端が凹部の底面で電気電解部材の１つの第１電極に対向するとともに、他端が基体の上面の蓋体が取着される部位に導出された第４配線導体と、一端が蓋体の下面で電解質部材の他の１つの第２電極に対向するとともに、他端が蓋体の下面の基体の上面に取着される部位に第４配線導体の他端と対向するように導出された第５配線導体とを具備していることから、複数個の電解質部材を電気的に接続することでそれらを直列接続することが可能となる。その結果、一つ一つの電解質部材の発電では微小電圧であっても、直列接続により合計の電圧の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことが可能となる。
【００６５】
また、本発明の第１および第２の燃料電池によれば、本発明の第１および第２の燃料電池用容器の凹部に電解質部材を収容して、この電解質部材の下側および上側主面を第１および第２流体流路との間でそれぞれの流体がやりとり可能なように配置するとともに、第１および第２電極を第１〜第３配線導体、ならびに第１，第２，第４および第５配線導体にそれぞれ電気的に接続し、基体の凹部の周囲の上面に凹部を覆って蓋体を取着して成ることから、以上のような本発明の第１および第２の燃料電池用容器による特長を備えた、小型・堅牢で、ガスの均等供給・燃料電池容器内の温度勾配の均一化・高効率な電気接続を図ることができる信頼性のある燃料電池を得ることができるとともに、複数個の電解質部材を並列接続することにより燃料電池全体の出力電流の調整ができるため、あるいは複数個の電解質部材を直列接続することにより合計の電圧の調整ができるため、電解質部材にて電気化学的に生成された電気を良好な状態で外部に取り出すことができる。
【００６６】
従って、本発明の燃料電池用容器および燃料電池によれば、コンパクト性、簡便性・安全性に優れ、ガスの均等供給・高効率な電気接続により、長期にわたり安定して作動させることができる燃料電池を提供することができた。
【図面の簡単な説明】
【図１】本発明の第１の燃料電池用容器およびそれを用いた本発明の第１の燃料電池の実施の形態の一例を示す断面図である。
【図２】本発明の第２の燃料電池用容器およびそれを用いた本発明の第２の燃料電池の実施の形態の一例を示す断面図である。
【図３】本発明の第２の燃料電池用容器およびそれを用いた本発明の第２の燃料電池の実施の形態の一例を示す平面図である。
【図４】従来の燃料電池の例を示す断面図である。
【符号の説明】
１，１’：燃料電池
２，２’：燃料電池用容器
３：電解質部材
４：第１電極
５：第２電極
６：基体
７：蓋体
８：第１流体流路
９：第２流体流路
１０：第１配線導体
１１：第２配線導体
１２：第３配線導体
１３：第４配線導体
１４：第５配線導体[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a small and highly reliable fuel cell container made of ceramics capable of accommodating an electrolyte member, and a fuel cell using the same.
[0002]
[Prior art]
In recent years, small fuel cells that operate at lower temperatures than ever have been actively developed. Depending on the type of electrolyte used for the fuel cell, a fuel cell such as a solid polymer electrolyte fuel cell (Polymer Electrolyte Fuel Cell: hereinafter referred to as PEFC), a phosphoric acid fuel cell, or a solid electrolyte fuel cell is known. ing.
[0003]
Above all, PEFC has a low operating temperature of about 80 to 100 ° C,
(1) High power density, enabling downsizing and weight reduction
(2) Since the electrolyte is not corrosive and has a low operating temperature, there are few restrictions on the battery constituent materials from the viewpoint of corrosion resistance, so that cost reduction is easy.
(3) Since it can be started at room temperature, the startup time is short,
It has such excellent features. For this reason, PEFC, taking advantage of the above features, is applicable not only to driving power supplies for vehicles and cogeneration systems for home use, but also to mobile phones, PDAs (Personal Digital Assistants), notebook computers, digital cameras, and the like. The use as a power supply for portable electronic devices having an output such as video of several W to several tens W has been considered.
[0004]
PEFCs are roughly classified into, for example, a fuel electrode (anode) composed of a carbon electrode to which catalyst particles such as platinum or platinum-ruthenium are attached, and an air electrode (cathode) composed of a carbon electrode to which catalyst particles such as platinum are attached. It has a film-shaped electrolyte member (hereinafter, referred to as an electrolyte member) interposed between the fuel electrode and the air electrode. Here, a hydrogen gas (H₂) Is supplied to the air electrode, while oxygen gas (O₂) Is supplied, predetermined electrical energy is generated (generated) by an electrochemical reaction, and electrical energy that is a driving power source (voltage / current) for the load is generated.
[0005]
Specifically, hydrogen gas (H₂) Is supplied, as shown in the following chemical reaction formula (1), electrons (e) are⁻) Separated hydrogen ion (proton; H⁺) Is generated and passes through the electrolyte member to the air electrode side, and electrons (e) are generated by the carbon electrode constituting the fuel electrode.⁻) Is taken out and supplied to the load.
3H₂ → 6H⁺+ 6e⁻ ... (1)
On the other hand, when air is supplied to the air electrode, as shown in the following chemical reaction formula (2), electrons (e⁻) And hydrogen ions (H⁺) And oxygen gas (O₂) Reacts with water (H₂O) is generated.
6H⁺+ 3 / 2O₂+ 6e⁻ → 3H₂O ... (2)
Such a series of electrochemical reactions (Equations (1) and (2)) proceed under relatively low temperature conditions of about 80 to 100 ° C., and by-products other than electric power are basically water (H₂O) only.
[0006]
The ionic conductive film (exchange membrane) constituting the electrolyte member is a polystyrene-based cation exchange membrane having sulfonic acid groups, a mixed membrane of fluorocarbon sulfonic acid and polyvinylidene fluoride, and trifluoroethylene grafted to a fluorocarbon matrix. Such materials are known, and recently, a perfluorocarbon sulfonic acid membrane (for example, Nafion: trade name, manufactured by DuPont) or the like is used.
[0007]
FIG. 3 is a sectional view showing a configuration of a conventional fuel cell (PEFC). In the figure, 21 is a PEFC, 23 is an electrolyte member, 24 and 25 are disposed on the electrolyte member 23 so as to sandwich the electrolyte member, and a pair of porous electrodes having a function as a gas diffusion layer and a catalyst layer, that is, Reference numeral 26 denotes a gas separator, reference numeral 28 denotes a fuel flow path, and reference numeral 29 denotes an air flow path.
[0008]
The gas separator 26 is provided so as to penetrate the laminated portion and the gas inflow / outlet frame forming the outer shape of the gas separator 26, the separator portion separating the fuel flow path 28 and the air flow path 29, and the separator portion. And electrodes arranged so as to correspond to the fuel electrode 24 and the air electrode 25 of the electrolyte member 23. A large number of fuel electrodes 24 and air electrodes 25 of the electrolyte member 23 are stacked via a gas separator 26 so as to be electrically connected in series and / or parallel to form a fuel cell stack which is the minimum unit of the battery. A stack containing the stack is a general PEFC main body.
[0009]
A fuel gas (hydrogen-rich gas) containing water vapor is supplied from a reformer to the fuel electrode 24 through a fuel flow path 28 formed in the gas separator 26, and the air electrode 25 is supplied to the air electrode 25 through an air flow path 29. Air is supplied as an oxidizing gas from the, and electric power is generated by a chemical reaction in the electrolyte member 23.
[0010]
[Patent Document 1]
JP 2001-266910 A
[Patent Document 2]
JP 2001-507501 A
[0011]
[Problems to be solved by the invention]
However, the fuel cell 21 conventionally proposed and developed as such a high-voltage and high-capacity battery is a heavy-weight and large-sized battery having a stack structure and a large-area component. The use of a fuel cell as a fuel cell has hardly been considered in the past.
[0012]
That is, in the conventional gas separator 26 of such a fuel cell 21, since the side surface of the electrolyte member 23 is exposed to the outside in the laminate in which the electrolyte member 23 is stacked by using the conventional gas separator 26, the gas separator 26 is dropped when carrying. There is a problem that the fuel cell 21 is liable to be damaged by such factors, and it is difficult to secure mechanical reliability of the entire fuel cell 21.
[0013]
In addition, in order to mount the fuel cell 21 on the portable electronic device, a fuel cell container which is different from the conventional large fuel and has excellent compactness, simplicity, and safety is required. In other words, in order to apply the battery as a portable power source such as a general-purpose chemical battery, the fuel cell container must be reduced in size and height to shorten the temperature rise to the operating temperature and to reduce the heat capacity. However, in the conventional fuel cell 21, the gas separator 26 occupying a large part of the heat capacity ratio is reduced in thickness, particularly in the case of the gas separator 26 in which a flow path is formed by cutting on the surface of a carbon plate. Since it becomes brittle, a thickness of several mm is required. For this reason, there is also a problem that it is difficult to reduce the size and height.
[0014]
Further, the output voltage of the fuel cell 21 is determined by the partial pressure of the gas supplied to the electrodes 24 and 25 on the front and back surfaces of the electrolyte member 23. That is, when the fuel gas supplied to the electrolyte member 23 travels through the gas flow path 28 and is consumed in the power generation reaction, the partial pressure of the fuel gas on the surface of the fuel electrode 24 decreases, and the output voltage decreases. Similarly, when the air also travels through the air flow path 29 and is consumed, the partial pressure of oxygen on the surface of the air electrode 25 decreases, and the output voltage decreases. Therefore, it is necessary to uniformly supply the fuel gas. However, the gas separator 26 of the conventional fuel cell 21 has a flow path formed by cutting the surface of the carbon plate, particularly when the thickness is reduced. Since the groove becomes narrower, the flow path resistance increases, and it is difficult to uniformly supply gas.
[0015]
Further, the combination of the plurality of electrolyte members 23 and the opposing fuel electrode 24, air electrode 25, and gas separator 26 are arbitrarily and efficiently connected in series or in parallel to adjust the overall output voltage and output current. However, in the conventional fuel cell 21, in order to extract electricity from the fuel electrode and the air electrode sandwiching the electrolyte member 23, the electricity is extracted and connected to the outside, or the gas separator 26 is stacked as a conductive material. There is only a method of connecting them together in series, and there is a problem that this is difficult in a small fuel cell.
[0016]
The present invention has been completed in view of the problems of the conventional technology as described above, and an object of the present invention is to provide a small, robust fuel cell container capable of storing an electrolyte member, and a method for equalizing gas. An object of the present invention is to provide a reliable fuel cell container capable of achieving a uniform temperature gradient in a supply / fuel cell container and highly efficient electrical connection, and a fuel cell using the same.
[0017]
[Means for Solving the Problems]
A first fuel cell container according to the present invention includes a base body made of ceramics having a concave portion on an upper surface for accommodating a plurality of electrolyte members having first and second electrodes on a lower side and an upper main surface, respectively. A first fluid flow path formed from a bottom surface of the concave portion facing the lower main surface to an outer surface of the base, and one end provided on a bottom surface of the concave portion facing the first electrode of the electrolyte member; A first wiring conductor whose other end is led out to an outer surface of the base, a lid body hermetically sealing the recess, attached to the upper surface of the base around the recess, covering the recess; A second fluid flow path formed from a lower surface of the lid facing the upper main surface of the electrolyte member to an outer surface of the lid, and the lid of the lid facing the second electrode of the electrolyte member; One end is disposed on the lower surface of the A second wiring conductor led out to the outer surface of the body and formed on the base, one end of which faces the first electrode of one of the electrolyte members at the bottom surface of the concave portion, and the other end of which is formed at the bottom surface of the concave portion. And a third wiring conductor facing the other one of the first electrodes of the electrolyte member.
[0018]
Further, a second fuel cell container of the present invention includes a base body made of ceramics having a concave portion on an upper surface for accommodating a plurality of electrolyte members having first and second electrodes on a lower side and an upper main surface, respectively. A first fluid flow path formed from a bottom surface of the concave portion facing the lower main surface of the member to an outer surface of the base; and one end disposed on a bottom surface of the concave portion facing the first electrode of the electrolyte member. A first wiring conductor having the other end formed over the outer surface of the base, and a lid hermetically sealing the recess, attached to the upper surface of the base around the recess to cover the recess. A second fluid flow path formed from a lower surface of the lid facing the upper main surface of the electrolyte member to an outer surface of the lid, and a lower surface of the lid facing the second electrode of the electrolyte member At one end and the other end at the front. The second wiring conductor led out to the outer surface of the lid, one end of which faces the one first electrode of the electrolyte member at the bottom surface of the concave portion, and the other end of which is attached to the lid of the base. A fourth wiring conductor led out to the upper surface, one end of which faces the other second electrode of the electrolyte member at the lower surface of the lid, and the other end is obtained on the upper surface of the base of the lid. And a fifth wiring conductor led out to face the other end of the fourth wiring conductor.
[0019]
In the first fuel cell of the present invention, a plurality of electrolyte members are accommodated in the concave portion of the first fuel cell container of the present invention having the above structure, and the lower and upper main surfaces of the electrolyte member are provided. Are arranged so that fluid can be exchanged with the first and second fluid flow paths, respectively, and the first and second wiring conductors are provided on the first and second electrodes, and the third wiring conductor is provided. Are electrically connected to the first electrodes, respectively, and the lid is attached to the upper surface of the base around the recess to cover the recess.
[0020]
In the second fuel cell of the present invention, a plurality of electrolyte members are accommodated in the concave portion of the second fuel cell container of the present invention having the above-described configuration, and the lower and upper main surfaces of the electrolyte member are provided. Are arranged such that respective fluids can be exchanged between the first and second fluid flow paths, and the first and second wiring conductors are provided on the first and second electrodes, and the fourth and fourth wiring conductors are provided on the first and second electrodes. A fifth wiring conductor is electrically connected to the first and second electrodes, respectively, and the upper surface around the concave portion of the base covers the concave portion and connects the other ends of the fourth and fifth wiring conductors. And the lid is attached.
[0021]
According to the first and second fuel cell containers of the present invention, a base made of ceramics having a concave portion on the upper surface for accommodating a plurality of electrolyte members having first and second electrodes on the lower and upper main surfaces, respectively; A lid that is attached to the upper surface around the recess of the base to cover the recess and hermetically seals the recess, so that the inside of the fuel cell container is hermetically sealed. Since there is no leakage of fluid such as gas and there is no need to provide a container such as a package in addition to this container, it is possible to obtain a fuel cell that can be operated efficiently and to be effective for miniaturization. Become. Further, since a plurality of electrolyte members can be housed in a box formed by a ceramic base having a recess on the upper surface and a lid sealing the recess, a fuel cell can be obtained. It is not exposed to the outside and is not damaged, and the mechanical reliability of the fuel cell as a whole is improved. In addition to the first to third wiring conductors, one end of which is disposed inside the container formed by the concave portion and the lid, or the first, second, fourth, and fifth wiring conductors, there is no need for the electrolyte member itself. As a result, a highly reliable and safe fuel cell can be obtained. Further, by using ceramics as a constituent material of the fuel cell container, it is possible to obtain a fuel cell having excellent corrosion resistance to various gases and other fluids.
[0022]
A first fluid flow path formed from the bottom surface of the concave portion facing the lower main surface of the electrolyte member to the outer surface of the base; and a first fluid flow channel formed from the lower surface of the lid facing the upper main surface of the electrolyte member to the outer surface of the lid. Since the plurality of fluid flow paths are provided on the inner wall surfaces facing each other with the electrolyte member interposed therebetween, the fluid supplied to the electrolyte member is provided. Can be more uniformly supplied. According to such a fluid path, since the fluid flows perpendicular to the electrolyte member, for example, when the fluid is a hydrogen gas and an air (oxygen) gas, the electrolyte member has the lower and upper main surfaces, respectively. The partial pressure of each gas supplied to the first and second electrodes does not decrease, and there is an effect that a predetermined stable output voltage can be obtained. Further, since the pressure of the supplied fluid, for example, the gas partial pressure is stabilized, the distribution of the internal temperature of the fuel cell container is made uniform, and as a result, the thermal stress generated in the electrolyte member can be suppressed. Reliability can be improved. Furthermore, since each fluid flow path is formed in the base and the lid, each flow path is excellent in hermeticity and two kinds of material fluids (for example, oxygen gas and hydrogen Gas or methanol) does not cause the fuel cell to lose its function, and there is no danger of ignition or explosion after the flammable fluid is mixed at a high temperature. Thus, a safe fuel cell can be provided.
[0023]
Further, according to the first fuel cell container of the present invention, one end formed on the base is opposed to one first electrode of the electrolyte member at the bottom surface of the recess, and the other end is formed at the bottom surface of the electrolyte member at the bottom surface of the recess. And the third wiring conductor facing the other one first electrode, the plurality of electrolyte members can be connected in parallel by electrically connecting the plurality of electrolyte members. As a result, the output current of the entire fuel cell can be adjusted, so that electricity generated electrochemically by the electrolyte member can be extracted to the outside in a good state.
[0024]
Furthermore, according to the second fuel cell container of the present invention, one end formed on the base having the recess accommodating the plurality of electrolyte members and the lid attached thereto has one end electrically connected to the bottom surface of the recess. A fourth wiring conductor which is opposed to one first electrode of the electrolytic member, the other end of which is led out to a portion of the upper surface of the base where the lid is attached; A fifth wiring conductor which is opposed to one second electrode and has a fifth wiring conductor led out to face the other end of the fourth wiring conductor at a position where the other end is attached to the upper surface of the base on the lower surface of the lid; Therefore, it is possible to connect a plurality of electrolyte members in series by electrically connecting them. As a result, even if a very small voltage is generated by each of the electrolyte members, the total voltage can be adjusted by series connection, so that the electricity electrochemically generated by the electrolyte members can be externally supplied in a good state. It can be taken out.
[0025]
Further, according to the first and second fuel cells of the present invention, the electrolyte member is accommodated in the concave portion of the first and second fuel cell containers of the present invention, and the lower and upper main surfaces of the electrolyte member are accommodated. Are arranged so that respective fluids can be exchanged with the first and second fluid flow paths, and the first and second electrodes are connected to the first to third wiring conductors, and the first, second, fourth And a fifth wiring conductor, respectively, and a lid is attached to the upper surface of the base around the concave so as to cover the concave. Thus, the first and second fuels of the present invention as described above are provided. It is possible to obtain a reliable, compact, robust fuel cell that has the features of a battery container and that can provide a uniform supply of gas, a uniform temperature gradient inside the fuel cell container, and highly efficient electrical connection. And by connecting multiple electrolyte members in parallel. Since the output current of the entire fuel cell can be adjusted, or the total voltage can be adjusted by connecting a plurality of electrolyte members in series, the electricity generated electrochemically by the electrolyte members can be adjusted in a good state. Can be taken out.
[0026]
Therefore, according to the fuel cell container and the fuel cell of the present invention, a fuel that is excellent in compactness, simplicity, and safety, and can be stably operated for a long period of time by uniform supply of fluid and highly efficient electrical connection. A battery can be provided.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, the present invention will be described in detail with reference to the accompanying drawings.
[0028]
FIG. 1 is a sectional view showing an example of an embodiment of a first fuel cell container of the present invention and a first fuel cell using the same. In FIG. 1, 1 is a fuel cell, 2 is a fuel cell container, 3 is an electrolyte member, 4 is a first electrode, 5 is a second electrode, 6 is a base, 7 is a lid, 8 is a first fluid flow path, 9 is a second fluid flow path, 10 is a first wiring conductor, 11 is a second wiring conductor, and 12 is a third wiring conductor.
[0029]
The electrolyte member 3 is, for example, on both main surfaces of the ion conductive film (exchange membrane) so as to face the first electrode 4 formed on the lower main surface and the second electrode 5 formed on the upper main surface, respectively. A fuel electrode (not shown) serving as an anode electrode and an air electrode (not shown) serving as a cathode electrode are integrally formed. Then, the current generated by the electrolyte member 3 flows to the first electrode 4 and the second electrode 5 and can be taken out.
[0030]
The ion conductive film (exchange membrane) of the electrolyte member 3 is made of a proton-conductive ion exchange resin such as a perfluorocarbon sulfonic acid resin, for example, Nafion (trade name, manufactured by DuPont). The fuel electrode and the air electrode are gas diffusion electrodes in a porous state, and have both functions of a porous catalyst layer and a gas diffusion layer. The fuel electrode and the air electrode are formed of a porous body in which conductive fine particles carrying a catalyst such as platinum / palladium or an alloy thereof, for example, carbon fine particles are held by a hydrophobic resin binder such as polytetrafluoroethylene. Have been.
[0031]
The first electrode 4 on the lower main surface of the electrolyte member 3 and the second electrode 5 on the upper main surface are formed by hot pressing a carbon electrode with catalyst fine particles such as platinum or platinum-ruthenium onto the electrolyte member 3, or And a method of applying or transferring a mixture of a carbon electrode material with catalyst fine particles such as platinum or platinum-ruthenium and a solution in which an electrolyte material is dispersed onto an electrolyte.
[0032]
The fuel cell container 2 is composed of a base 6 having a concave portion and a lid 7, has a role of mounting the electrolyte member 3 inside the concave portion and hermetically sealing the same, and is made of aluminum oxide (Al).₂O₃) Sintered body, mullite (3Al₂O₃・ 2SiO₂) Sintered body, silicon carbide (SiC) based sintered body, aluminum nitride (AlN) based sintered body, silicon nitride (Si₃N₄) It is formed of a ceramic material such as a sintered compact or a glass-ceramic sintered compact.
[0033]
The glass-ceramic sintered body is composed of a glass component and a filler component.₂-B₂O₃System, SiO₂-B₂O₃-Al₂O₃System, SiO₂-B₂O₃-Al₂O₃-MO system (however, M represents Ca, Sr, Mg, Ba or Zn), SiO₂-Al₂O₃-M¹OM²O type (however, M¹And M²Represent the same or different Ca, Sr, Mg, Ba or Zn), SiO₂-B₂O₃-Al₂O₃-M¹OM²O type (however, M¹And M²Is the same as above), SiO₂-B₂O₃-M³ ₂O type (however, M³Represents Li, Na or K), SiO₂-B₂O₃-Al₂O₃-M³ ₂O type (however, M³Is the same as described above), Pb-based glass, Bi-based glass and the like.
[0034]
As the filler component, for example, Al₂O₃, SiO₂, ZrO₂Oxide of TiO2 and alkaline earth metal oxide, TiO₂Oxide of aluminum and alkaline earth metal oxide, Al₂O₃And SiO₂And complex oxides containing at least one selected from the group consisting of spinel, mullite, cordierite, and the like.
[0035]
The fuel cell container 2 includes a base 6 having a concave portion and a lid 7. The lid 6 is attached around the concave portion of the base 6 so as to cover the concave portion and hermetically seal the concave portion. Bonding with a metal bonding material such as iron or silver solder, bonding with a resin material such as epoxy, bonding a seal ring made of an iron alloy or the like to the upper surface around the recess, and using seam welding, electron beam, laser, etc. The lid 7 is attached to the base 6 by a welding method or the like. Note that a recess similar to the base 6 may be formed in the lid 7.
[0036]
In order to reduce the thickness of each of the base 6 and the lid 7 and enable the height of the fuel cell 1 to be reduced, the bending strength, which is a mechanical strength, is preferably 200 MPa or more.
[0037]
The base 6 and the lid 7 are preferably formed of a dense aluminum oxide sintered body having a relative density of, for example, 95% or more. In that case, for example, first, a rare earth oxide powder and a sintering aid are added to and mixed with the aluminum oxide powder to adjust the raw material powder of the aluminum oxide sintered body. Next, an organic binder and a dispersion medium are added to and mixed with the raw material powder of the aluminum oxide sintered body to form a paste, and the paste is added to the raw material powder by a doctor blade method, or an organic binder is added to the raw material powder, for example, press forming, rolling forming, and the like. Thus, a green sheet having a predetermined thickness is produced. Then, through-holes as the first fluid flow path 8 and the second fluid flow path 9, the first wiring conductor 10, the second wiring conductor A through hole for disposing the first wiring conductor 11 and the third wiring conductor 12 is formed.
[0038]
The first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12 are preferably formed of tungsten and / or molybdenum to prevent oxidation. In that case, for example, 100 parts by mass of tungsten and / or molybdenum powder as an inorganic component, Al₂O₃3 to 20 parts by mass, Nb₂O₅Is added at a ratio of 0.5 to 5 parts by mass to prepare a conductor paste. This conductive paste is filled into the through holes of the green sheet to form via conductors as through conductors.
[0039]
In these conductor pastes, in order to enhance the adhesion of the base 6 and the lid 7 to the ceramics, aluminum oxide powder or the same composition powder as the ceramic component forming the base 6 or the lid 7 is used, for example. It is also possible to add 0.05 to 2% by volume.
[0040]
The first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12 are formed on the surface layer and the inner layer of the base 6 and the lid 7 before and after the through-hole is filled with the conductive paste to form the via conductor. Alternatively, at the same time, a similar conductive paste is formed by printing and applying a predetermined pattern on the green sheet by a method such as screen printing or gravure printing.
[0041]
Then, after a predetermined number of sheet-shaped molded bodies filled with printed and filled conductor paste are laminated and pressure-bonded, the laminated body is heated, for example, in a non-oxidizing atmosphere at a maximum firing temperature of 1200 to 1500 ° C. To obtain the desired ceramic base 6, lid 7, first wiring conductor 10, second wiring conductor 11, and third wiring conductor 12.
[0042]
Further, it is preferable that the thickness of the base 6 and the lid 7 made of ceramics be 0.2 mm or more. If the thickness is less than 0.2 mm, the strength tends to be insufficient, so that the stress generated when the cover 7 is attached to the base 6 tends to easily cause cracks and the like in the base 6 and the cover 7. . On the other hand, if the thickness exceeds 5 mm, it becomes difficult to reduce the thickness and height of the electrolyte member 3 because it is difficult to reduce the thickness and height of the electrolyte member 3. There is a tendency that it is difficult to quickly set an appropriate temperature corresponding to the condition.
[0043]
The first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12 are electrically connected to the first electrode 4 and the second electrode 5 of the electrolyte member 3, respectively, so that a current generated by the electrolyte member 3 is generated. It functions as a conductive path for taking out the fuel cell container 2 to the outside.
[0044]
One end of the first wiring conductor 10 is provided at a portion of the bottom surface of the concave portion of the base 6 facing the first electrode 4 of the electrolyte member 3, and the other end is formed to extend to the outer surface of the base 6. Such a first wiring conductor 10 is formed integrally with the base 6 as described above. Further, the first wiring conductor 10 is desirably formed to be at least 10 μm higher than the bottom surface of the concave portion of the base 6 so that both ends of the first wiring conductor 10 are easily brought into contact with the first electrode 4. In order to obtain this height, when forming the conductor paste by printing as described above, printing conditions may be set so as to increase the applied thickness. Further, it is desirable that a plurality of first wiring conductors 10 are arranged so as to face the first electrode 4 so as to reduce the electric loss due to the first wiring conductors 10. Is preferable.
[0045]
Further, one end of the second wiring conductor 11 is provided at a portion of the lower surface of the lid 7 facing the second electrode 5 of the electrolyte member 3, and the other end is formed so as to be led out to the outer surface of the lid 7. . Such a second wiring conductor 11 is also formed integrally with the lid 7 like the first wiring conductor 10. The second wiring conductor 11 is desirably formed so as to be at least 10 μm higher than the lower surface of the lid 7 so that both ends of the second wiring conductor 11 are easily brought into contact with the second electrode 5. In order to obtain this height, when forming the conductor paste by printing as described above, printing conditions may be set so as to increase the applied thickness. Further, it is desirable that a plurality of second wiring conductors 11 are arranged so as to face the second electrode 5 so as to reduce the electric loss due to the second wiring conductors 11. Preferably, the diameter is not less than the above.
[0046]
In addition, one end of the third wiring conductor 12 is disposed at a portion of the bottom surface of the concave portion of the base body 6 facing the first electrode 4 of the electrolyte member 3, and the other end is provided at the bottom surface of the same concave portion at the other end of the electrolyte member 3. And is formed integrally with the base 6 at a position facing one of the first electrodes 4. The third wiring conductor 12 is desirably formed so as to be higher than the bottom surface of the concave portion of the base 6 by 10 μm or more so that both ends of the third wiring conductor 12 are easily brought into contact with the first electrode 4. In order to obtain this height, when forming the conductor paste by printing as described above, printing conditions may be set so as to increase the applied thickness. Further, it is preferable that a plurality of third wiring conductors 12 are arranged so as to face the first electrode 4 so as to reduce the electric loss due to the third wiring conductors 12. Is preferable.
[0047]
The first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12 are plated with a metal having good conductivity made of nickel, having good corrosion resistance and good wettability with a brazing material on the exposed surfaces. The first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12, and the first wiring conductor 10, the second wiring conductor 11, the third wiring conductor 12, and the external electric circuit Good electrical connection can be achieved. Therefore, the first wiring conductor 10, the second wiring conductor 11, and the third wiring conductor 12 are plated with a metal having good conductivity made of nickel, having good corrosion resistance and good wettability with the brazing material on the exposed surfaces. It is preferable to apply it by a method.
[0048]
The electrical connection between the first, second, and third wiring conductors 10, 11, 12 and the first and second electrodes 4, 5 is performed by sandwiching the electrolyte member 3 between the base 6 and the lid 7. Thus, the first, second, and third wiring conductors 10, 11, 12 and the first and second electrodes 4, 5 may be brought into pressure contact with each other to electrically connect them.
[0049]
Further, a first fluid flow path 8 and a second fluid flow path 9 are arranged on the bottom surface of the concave portion of the base 6 facing the first electrode 4 and the second electrode 5 and on the lower surface of the lid 7, respectively. The one fluid channel 8 is formed over the outer surface of the base 6, and the second fluid channel 9 is formed over the outer surface of the lid 7. These first and second fluid flow paths 8 and 9 are formed by a through hole or a groove formed in the base 6 or the lid 7, respectively, so that a fuel gas such as a hydrogen-rich reformed gas or an oxidizing gas such as air is used to form an electrolyte. It is provided as a passage for a fluid supplied to the member 3 or as a passage for a fluid such as water generated by the reaction and discharged from the electrolyte member 3 after the reaction.
[0050]
The through-holes or grooves formed in the base 6 and the lid 7 as the first fluid flow path 8 and the second fluid flow path 9 are such that a fluid such as a fuel gas or an oxidizing gas is uniformly supplied to the electrolyte member 3. The diameter and number of the through holes or the width, depth, and arrangement of the grooves may be determined according to the specifications of the fuel cell 1.
[0051]
In the first fuel cell container 2 and the first fuel cell 1 of the present invention, the first fluid passage 8 and the second fluid passage 9 preferably supply fluid to the electrolyte member 3 at a uniform pressure. In order to flow, it is preferable to arrange the holes with a diameter of 0.1 mm or more and a constant interval.
[0052]
As described above, the first fluid flow path 8 is opposed to the lower main surface on which the first electrode 4 of the electrolyte member 3 is formed, and the second fluid flow path 8 is opposed to the upper main surface on which the second electrode 5 is formed. By forming the passage 9, fluid can be exchanged between the lower and upper main surfaces of the electrolyte member 3 and the first and second fluid passages 8, 9, and the fluid can be supplied through the respective passages. Will be discharged. If, for example, gas is supplied as a fluid, the partial pressure of gas supplied to the first electrode 4 and the second electrode 5 of the electrolyte member 3 can be prevented from decreasing, and a predetermined stable output voltage can be obtained. Can be obtained. Further, since the supplied gas partial pressure is stabilized, the internal pressure of the fuel cell 1 is made uniform, and as a result, thermal stress generated in the electrolyte member 3 can be suppressed. Performance can be improved.
[0053]
With the above configuration, as shown in FIG. 1, a small and robust first fuel cell container 2 of the present invention capable of storing the electrolyte member 3 is obtained, and the first fuel cell container 2 of the present invention capable of highly efficient control is provided. Is obtained.
[0054]
Next, FIG. 2 is a sectional view showing an example of an embodiment of a fuel cell container of the present invention and a second fuel cell using the same, and FIG. 3 is a plan view thereof. In these figures, 1 'is a fuel cell, 2' is a fuel cell container, 3 is an electrolyte member, 4 is a first electrode, 5 is a second electrode, 6 is a base, 7 is a lid, and 8 is a first fluid. The flow path, 9 is a second fluid flow path, 10 is a first wiring conductor, 11 is a second wiring conductor, 13 is a fourth wiring conductor, and 14 is a fifth wiring conductor.
[0055]
2 and 3 are the same as in FIG. One end of the fourth wiring conductor 13 is disposed on the bottom surface of the concave portion of the base 6 at a position facing one of the first electrodes 4 of the plurality of electrolyte members 3. It is led to the part to be attached. In addition, one end of the fifth wiring conductor 14 is disposed at a portion of the lower surface of the lid 7 that faces the other one of the second electrodes 5 of the plurality of electrolyte members 3, and the other end is formed on the lower surface of the lid 7. It is led out and formed at a portion attached to the upper surface of the base 6 so as to face the other end of the fourth wiring conductor 13.
[0056]
Like the third wiring conductor 12, such a fourth wiring conductor 13 is formed integrally with the base 6, and one end thereof is at least 10 μm from the bottom surface of the concave portion of the base 6 so that one end of the fourth wiring conductor 13 is easily brought into contact with the first electrode 4. It is desirable to form it to be high. In order to obtain this height, when forming the conductor paste by printing as described above, printing conditions may be set so as to increase the applied thickness. Further, it is desirable that a plurality of fourth wiring conductors 13 are arranged so as to face the first electrode 4 so as to reduce the electric loss due to the fourth wiring conductors 13. Is preferable.
[0057]
Similarly to the second wiring conductor 11, the fifth wiring conductor 14 is also formed integrally with the lid 7, and one end thereof is higher than the lower surface of the lid 7 by 10 μm or more so as to easily contact the second electrode 5. It is desirable to form it. In order to obtain this height, when forming the conductor paste by printing as described above, printing conditions may be set so as to increase the applied thickness. Further, it is desirable that a plurality of fifth wiring conductors 14 are also arranged so as to face the second electrode 5 so as to reduce the electric loss due to the fifth wiring conductors 14. Preferably, the diameter is not less than the above.
[0058]
As shown in FIGS. 1, 2 and 3, according to the first and second fuel cell containers 2.2 ′ and the first and second fuel cells 1.1 ′ of the present invention, A plurality of electrolyte members 3 are accommodated in the concave portions, and the third wiring conductor 12 or the fourth wiring conductor 13 and the fifth wiring conductor 14 are provided, between the first electrodes 4 of the plurality of electrolyte members 3, or The first wiring conductor 10 and the second wiring conductor 11 are electrically connected between the first electrode 4 and the second electrode 5 so as to take out the output as a whole to the electrolyte members 3 arranged at the ends. Are electrically connected to each other, so that the first, second, fourth, and fifth wiring conductors 10, 11, 13, and 14 form a three-dimensional structure by the first to third wiring conductors 10, 11, and 12. Since the wiring can be made freely, the plurality of electrolyte members 3 can be arbitrarily It is possible to connect or parallel connection. As a result, it is possible to efficiently adjust the entire output voltage and output current. Become.
[0059]
It should be noted that the present invention is not limited to the above embodiments, and various changes may be made without departing from the scope of the present invention. For example, the first fluid flow path and the second fluid flow path may be provided with an inlet from the side surface of the base or the lid in order to reduce the thickness of the entire fuel cell. This is particularly effective for miniaturization of portable electronic devices. Further, the first and second wiring conductors may be arranged so that the other ends led out to the outer surfaces of the base and the lid are respectively drawn to the side surfaces on the same side. According to this, the wiring, the flow path, and the like can be integrated on one side of the fuel cell, the miniaturization and the protection of the joint to the outside can be easily performed, and a highly reliable design can be performed. A fuel cell that can operate stably.
[0060]
【The invention's effect】
According to the first and second fuel cell containers of the present invention, a base made of ceramics having a concave portion on its upper surface for accommodating an electrolyte member having first and second electrodes on the lower and upper main surfaces, respectively, Since a lid is provided on the upper surface around the concave portion of the base body so as to cover the concave portion and hermetically seals the concave portion, the inside of the fuel cell container is hermetically sealed, so that There is no need to provide a container such as a package in addition to this container, so that it is possible to obtain a fuel cell that can be operated efficiently, and it is also effective for miniaturization. Further, since a plurality of electrolyte members can be housed in a box formed by a ceramic base having a recess on the upper surface and a lid sealing the recess, a fuel cell can be obtained. It is not exposed to the outside and is not damaged, and the mechanical reliability of the fuel cell as a whole is improved. In addition to the first to third wiring conductors, one end of which is disposed inside the container formed by the concave portion and the lid, or the first, second, fourth, and fifth wiring conductors, there is no need for the electrolyte member itself. As a result, a highly reliable and safe fuel cell can be obtained. Further, by using ceramics as a constituent material of the fuel cell container, it is possible to obtain a fuel cell having excellent corrosion resistance to various gases and other fluids.
[0061]
A first fluid flow path formed from the bottom surface of the concave portion facing the lower main surface of the electrolyte member to the outer surface of the base; and a first fluid flow channel formed from the lower surface of the lid facing the upper main surface of the electrolyte member to the outer surface of the lid. Since the plurality of fluid flow paths are provided on the inner wall surfaces facing each other with the electrolyte member interposed therebetween, the fluid supplied to the electrolyte member is provided. Can be more uniformly supplied. According to such a fluid path, since the fluid flows perpendicular to the electrolyte member, for example, when the fluid is a hydrogen gas and an air (oxygen) gas, the electrolyte member has the lower and upper main surfaces, respectively. The partial pressure of each gas supplied to the first and second electrodes does not decrease, and there is an effect that a predetermined stable output voltage can be obtained. Further, since the pressure of the supplied fluid, for example, the gas partial pressure is stabilized, the distribution of the internal temperature of the fuel cell container is made uniform, and as a result, the thermal stress generated in the electrolyte member can be suppressed. Reliability can be improved. Furthermore, since each fluid flow path is formed in the base and the lid, each flow path is excellent in hermeticity and two kinds of material fluids (for example, oxygen gas and hydrogen Gas or methanol) does not cause the fuel cell to lose its function, and there is no danger of ignition or explosion after the flammable fluid is mixed at a high temperature. Thus, a safe fuel cell can be provided.
[0062]
Further, according to the first and second fuel cells of the present invention, the electrolyte member is accommodated in the concave portion of the first and second fuel cell containers of the present invention, and the lower and upper main surfaces of the electrolyte member are accommodated. Are arranged so that respective fluids can be exchanged with the first and second fluid flow paths, and the first and second electrodes are connected to the first to third wiring conductors, and the first, second, fourth And the fifth wiring conductor are electrically connected to each other, and the lid is attached to the upper surface around the concave portion of the base so as to cover the concave portion, so that the electrolyte member is not exposed and damaged, and The first to third wiring conductors, one end of which is disposed inside the container formed by the concave portion and the lid, and the first, second, fourth, and fifth wiring conductors, and unnecessary electricity for the electrolyte member. A reliable and safe fuel cell because no electrical contact is required Door can be. Further, since the first and second fluid flow paths are provided on the bottom surface of the concave portion of the base body and the lower surface of the lid, which are the inner wall surfaces opposed to each other with the electrolyte member interposed therebetween, the gas supplied to the electrolyte member is The uniform supply property can be improved, and the partial pressure of the gas supplied to the first and second electrodes of the electrolyte member can be prevented from decreasing, so that a predetermined stable output voltage can be obtained. And the stress which arises in an electrolyte member can also be suppressed and reliability can be improved.
[0063]
Further, according to the first fuel cell container of the present invention, one end formed on the base is opposed to one first electrode of the electrolyte member at the bottom surface of the recess, and the other end is formed at the bottom surface of the electrolyte member at the bottom surface of the recess. And the third wiring conductor facing the other one first electrode, the plurality of electrolyte members can be connected in parallel by electrically connecting the plurality of electrolyte members. As a result, the output current of the entire fuel cell can be adjusted, so that electricity generated electrochemically by the electrolyte member can be extracted to the outside in a good state.
[0064]
Furthermore, according to the second fuel cell container of the present invention, one end formed on the base having the recess accommodating the plurality of electrolyte members and the lid attached thereto has one end electrically connected to the bottom surface of the recess. A fourth wiring conductor which is opposed to one first electrode of the electrolytic member, the other end of which is led out to a portion of the upper surface of the base where the lid is attached; A fifth wiring conductor which is opposed to one second electrode and has a fifth wiring conductor led out to face the other end of the fourth wiring conductor at a position where the other end is attached to the upper surface of the base on the lower surface of the lid; Therefore, it is possible to connect a plurality of electrolyte members in series by electrically connecting them. As a result, even if a very small voltage is generated by each of the electrolyte members, the total voltage can be adjusted by series connection, so that the electricity electrochemically generated by the electrolyte members can be externally supplied in a good state. It can be taken out.
[0065]
Further, according to the first and second fuel cells of the present invention, the electrolyte member is accommodated in the concave portion of the first and second fuel cell containers of the present invention, and the lower and upper main surfaces of the electrolyte member are accommodated. Are arranged so that respective fluids can be exchanged with the first and second fluid flow paths, and the first and second electrodes are connected to the first to third wiring conductors, and the first, second, fourth And a fifth wiring conductor, respectively, and a lid is attached to the upper surface of the base around the concave so as to cover the concave. Thus, the first and second fuels of the present invention as described above are provided. It is possible to obtain a reliable, compact, robust fuel cell that has the features of a battery container and that can provide a uniform supply of gas, a uniform temperature gradient inside the fuel cell container, and highly efficient electrical connection. And by connecting multiple electrolyte members in parallel. Since the output current of the entire fuel cell can be adjusted, or the total voltage can be adjusted by connecting a plurality of electrolyte members in series, the electricity generated electrochemically by the electrolyte members can be adjusted in a good state. Can be taken out.
[0066]
Therefore, according to the fuel cell container and the fuel cell of the present invention, a fuel which is excellent in compactness, simplicity and safety, and can be stably operated for a long period of time by uniform supply of gas and highly efficient electric connection. Battery could be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an embodiment of a first fuel cell container of the present invention and a first fuel cell of the present invention using the same.
FIG. 2 is a sectional view showing an example of an embodiment of a second fuel cell container of the present invention and a second fuel cell of the present invention using the container.
FIG. 3 is a plan view showing an example of an embodiment of a second fuel cell container of the present invention and a second fuel cell of the present invention using the same.
FIG. 4 is a sectional view showing an example of a conventional fuel cell.
[Explanation of symbols]
1, 1 ': fuel cell
2, 2 ': container for fuel cell
3: Electrolyte member
4: First electrode
5: Second electrode
6: Substrate
7: Lid
8: First fluid flow path
9: Second fluid flow path
10: first wiring conductor
11: second wiring conductor
12: Third wiring conductor
13: Fourth wiring conductor
14: Fifth wiring conductor

Claims

A base body made of ceramic having a concave portion on the upper surface for accommodating a plurality of electrolyte members having first and second electrodes on the lower and upper main surfaces, respectively; and a bottom surface of the concave portion facing the lower main surface of the electrolyte member A first fluid flow path formed from the first member to the outer surface of the base, and one end disposed on the bottom surface of the concave portion facing the first electrode of the electrolyte member, and the other end being led to the outer surface of the base. (1) a wiring conductor, a lid which is attached to an upper surface around the recess of the base so as to cover the recess, and hermetically seals the recess, and the lid facing the upper main surface of the electrolyte member A second fluid flow path formed from the lower surface of the body to the outer surface of the lid, and one end is provided on the lower surface of the lid of the lid facing the second electrode of the electrolyte member, and the other end is provided. The second wiring conductor led out to the outer surface of the lid And one end of the other one of the first and second electrodes of the electrolyte member is formed on the base, one end of which faces the first electrode of the electrolyte member at the bottom surface of the recess. And a third wiring conductor facing the fuel cell container.

A base body made of ceramic having a concave portion on the upper surface for accommodating a plurality of electrolyte members having first and second electrodes on the lower and upper main surfaces, respectively; and a bottom surface of the concave portion facing the lower main surface of the electrolyte member A first fluid flow path formed from the outer surface of the base to an outer surface of the base, and a first end formed on the bottom surface of the concave portion facing the first electrode of the electrolyte member, and the other end formed on the outer surface of the base. (1) a wiring conductor, a lid which is attached to an upper surface around the recess of the base so as to cover the recess, and hermetically seals the recess, and the lid facing the upper main surface of the electrolyte member A second fluid flow path formed from the lower surface of the body to the outer surface of the lid, and one end is disposed on the lower surface of the lid facing the second electrode of the electrolyte member, and the other end is provided on the lid. The second wiring conductor led out to the outer surface One end faces the first electrode of one of the electrolyte members at the bottom surface of the concave portion, and the other end is a fourth wiring conductor led out to the upper surface of the base body to which the lid is attached; The lower surface of the lid faces the other one of the second electrodes of the electrolyte member, and the other end faces the other end of the fourth wiring conductor on the lower surface obtained on the upper surface of the base of the lid. And a fifth wiring conductor derived as described above.

2. A plurality of electrolyte members are accommodated in the concave portion of the fuel cell container according to claim 1, and the lower and upper main surfaces of the electrolyte members are respectively fluidized between the first and second fluid flow paths. The first and second wiring conductors are electrically connected to the first and second electrodes, and the third wiring conductor is electrically connected to the first electrode, respectively. A fuel cell, wherein the lid is attached to an upper surface around the recess to cover the recess.

A plurality of electrolyte members are accommodated in the concave portion of the fuel cell container according to claim 2, and the lower and upper main surfaces of the electrolyte members are respectively arranged between the first and second fluid flow paths. The first and second wiring conductors are electrically connected to the first and second electrodes, and the fourth and fifth wiring conductors are electrically connected to the first and second electrodes, respectively. And connecting the other ends of the fourth and fifth wiring conductors to each other to cover the upper surface around the concave portion of the base, and attaching the lid. Fuel cell.