JP3064023B2 - Gas separator for fuel cells - Google Patents
Gas separator for fuel cellsInfo
- Publication number
- JP3064023B2 JP3064023B2 JP3028339A JP2833991A JP3064023B2 JP 3064023 B2 JP3064023 B2 JP 3064023B2 JP 3028339 A JP3028339 A JP 3028339A JP 2833991 A JP2833991 A JP 2833991A JP 3064023 B2 JP3064023 B2 JP 3064023B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- gas supply
- cooling water
- fuel
- plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0204—Non-porous and characterised by the material
- H01M8/0206—Metals or alloys
- H01M8/0208—Alloys
- H01M8/021—Alloys based on iron
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0204—Non-porous and characterised by the material
- H01M8/0206—Metals or alloys
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0204—Non-porous and characterised by the material
- H01M8/0223—Composites
- H01M8/0228—Composites in the form of layered or coated products
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0267—Collectors; Separators, e.g. bipolar separators; Interconnectors having heating or cooling means, e.g. heaters or coolant flow channels
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
- H01M8/04067—Heat exchange or temperature measuring elements, thermal insulation, e.g. heat pipes, heat pumps, fins
- H01M8/04074—Heat exchange unit structures specially adapted for fuel cell
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/2465—Details of groupings of fuel cells
- H01M8/2483—Details of groupings of fuel cells characterised by internal manifolds
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0082—Organic polymers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Composite Materials (AREA)
- Fuel Cell (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、イオン交換膜を使用す
る燃料電池用のガスセパレータに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas separator for a fuel cell using an ion exchange membrane.
【０００２】[0002]
【従来の技術】燃料電池は、資源の枯渇問題を有する化
石燃料を使う必要がない上、騒音をほとんど発生せず、
エネルギの回収効率も他のエネルギ機関と較べて非常に
高くできる等の優れた特徴を持っているため、例えばビ
ルディング単位や工場単位の比較的小型の発電プラント
として利用されている。近年、この燃料電池を車載用の
内燃機関に代えて作動するモータの電源として利用し、
このモータにより車両等を駆動することが考えられてい
る。この場合に重要なことは、反応によって生成する物
質をできるだけ再利用することは当然のこととして、車
載用であることからも明らかなように、余り大きな出力
は必要でないものの、全ての付帯設備と共に可能な限り
小型であることが望ましく、このような点からイオン交
換膜を使用する燃料電池、特に固体高分子電解質膜燃料
電池が注目されている。2. Description of the Related Art Fuel cells do not need to use fossil fuels, which have a problem of resource depletion, and generate almost no noise.
Since it has excellent features such as an extremely high energy recovery efficiency as compared with other energy engines, it is used as a relatively small power plant, for example, in a building unit or a factory unit. In recent years, this fuel cell has been used as a power source for a motor that operates in place of a vehicle-mounted internal combustion engine,
It has been considered that a vehicle or the like is driven by this motor. In this case, it is important to recycle as much as possible the substances generated by the reaction. It is desirable that the size is as small as possible. From such a point, a fuel cell using an ion exchange membrane, in particular, a solid polymer electrolyte membrane fuel cell has attracted attention.
【０００３】ここで、一例として固体高分子電解質膜燃
料電池本体の基本構造を図５を参照しながら説明する。
同図に示すように、電池本体０１は固体高分子電解質膜
０２の両側にガス拡散電極０３Ａ，０３Ｂが接合される
ことにより構成されている。そしてこの接合体は、固体
高分子電解質膜０２の両側にガス拡散電極０３Ａ，０３
Ｂを合せた後、ホットプレス等することにより製造され
る。また、ガス拡散電極０３Ａ，０３Ｂはそれぞれ反応
膜０４Ａ，０４Ｂ及びガス拡散膜０５Ａ，０５Ｂが接合
されたものであり、電解質膜０２とは反応膜０４Ａ，０
４Ｂの表面が接触している。したがって、電池反応は主
に電解質膜０２と反応膜０４Ａ，０４Ｂとの間の接触面
で起こる。また、上記ガス拡散電極０３Ａの表面には、
酸素供給溝０６ａを有するガスセパレータが、また他方
のガス拡散電極０３Ｂの表面には水素供給溝０７ａを有
するガスセパレータ０７がそれぞれ接合されており、酸
素極と水素極を構成している。Here, as an example, the basic structure of a solid polymer electrolyte membrane fuel cell body will be described with reference to FIG.
As shown in the figure, a battery main body 01 is configured by joining gas diffusion electrodes 03A and 03B to both sides of a solid polymer electrolyte membrane 02. The joined body is provided on both sides of the solid polymer electrolyte membrane 02 with gas diffusion electrodes 03A and 03A.
It is manufactured by hot pressing or the like after combining B. The gas diffusion electrodes 03A and 03B are formed by bonding reaction films 04A and 04B and gas diffusion films 05A and 05B, respectively.
The surface of 4B is in contact. Therefore, the battery reaction mainly occurs at the contact surface between the electrolyte membrane 02 and the reaction membranes 04A and 04B. Further, on the surface of the gas diffusion electrode 03A,
A gas separator having an oxygen supply groove 06a is joined to a gas separator 07 having a hydrogen supply groove 07a on the surface of the other gas diffusion electrode 03B, and constitutes an oxygen electrode and a hydrogen electrode.
【０００４】そして、酸素供給溝０６ａ及び水素供給溝
０７ａは酸素及び水素をそれぞれ供給すると、酸素，水
素は、各々のガス拡散膜０５Ａ，０５Ｂを介して反応膜
０４Ａ，０４Ｂ側へ供給され、各反応膜０４Ａ，０４Ｂ
と電解質膜０２との界面で次のような反応が起こる。 反応膜０４Ａの界面： Ｏ2 ＋４Ｈ+ ＋４ｅ- →２Ｈ2 Ｏ 反応膜０４Ｂの界面： ２Ｈ2 →４Ｈ+ ＋４ｅ- ここで、４Ｈ+ は電解質膜０２を通って水素極から酸素
極へ流れるが、４ｅ- は負荷０８を通って水素極から酸
素極へ流れることになり、電気エネルギが得られる。When oxygen and hydrogen are supplied to the oxygen supply groove 06a and the hydrogen supply groove 07a, respectively, oxygen and hydrogen are supplied to the reaction films 04A and 04B via the gas diffusion films 05A and 05B, respectively. Reaction membrane 04A, 04B
The following reaction occurs at the interface between the electrolyte membrane 02 and the electrolyte. Interface of the reaction film 04A: O 2 + 4H + + 4e − → 2H 2 O Interface of the reaction film 04B: 2H 2 → 4H + + 4e − Here, 4H + flows from the hydrogen electrode to the oxygen electrode through the electrolyte membrane 02, 4e - is will flow from the hydrogen electrode to the oxygen electrode through the load 08, electrical energy is obtained.
【０００５】このような燃料電池において、ガスセパレ
ータ０６，０７のような燃料電池用ガスセパレータは、
各々の背面に燃料ガスと酸化剤ガスを均一に且つ完全に
分離して供給し、さらに、反応によって発生した電気を
効率よく集電するという性能を有する必要がある。ま
た、電池反応による発熱が大きいので、運転条件の安定
化を図るためには反応熱をガスセパレータを介して放熱
させる必要がある。In such a fuel cell, gas separators for fuel cells such as gas separators 06 and 07 are
It is necessary that the fuel gas and the oxidizing gas are uniformly and completely separated and supplied to each back surface, and that the gas generated by the reaction is efficiently collected. Further, since heat generated by the battery reaction is large, it is necessary to dissipate the reaction heat through the gas separator in order to stabilize the operating conditions.
【０００６】したがって、従来においては、両面にガス
供給溝を形成したガスセパレータと、固体高分子電解質
膜及びガス拡散電極の接合体とを順次複数枚重ね合せて
多重電池セルとすると共に該電池セルの周辺に冷却水ジ
ャケットを設けたり、数枚のセル間隔毎に冷却盤を挿入
した構造が採用されている。また、ガスセパレータのガ
ス供給溝の形成面に、ガス供給溝と共に冷却水供給溝を
形成し、ガス拡散電極の背面に直接接触するように冷却
水を流して電解質膜の直接加湿も兼ねるという構造も知
られている。Therefore, in the prior art, a plurality of gas separators each having gas supply grooves formed on both surfaces thereof and a joined body of a solid polymer electrolyte membrane and a gas diffusion electrode are sequentially laminated to form a multiple battery cell. A cooling water jacket is provided in the periphery of the cell, or a cooling board is inserted at intervals of several cells. In addition, a cooling water supply groove is formed together with the gas supply groove on the gas supply groove forming surface of the gas separator, and the cooling water flows so as to directly contact the back surface of the gas diffusion electrode, thereby also serving as a direct humidifier for the electrolyte membrane. Is also known.
【０００７】[0007]
【発明が解決しようとする課題】前述した固体高分子膜
燃料電池の特長はコンパクトで且つ高性能なことであ
る。そして、ガス拡散電極の厚さが１〜１．５mmである
ことを考えると、ガスセパレータの構造及び厚さで燃料
電池の大きさが決定されるとも言える。The features of the solid polymer membrane fuel cell described above are compact and high performance. Considering that the thickness of the gas diffusion electrode is 1 to 1.5 mm, it can be said that the size of the fuel cell is determined by the structure and thickness of the gas separator.
【０００８】一方、前述したガスセパレータの機能を得
るためには、ガス拡散電極へガス供給するためのガス供
給溝をできるだけ細分化してガス拡散電極の表面全体に
亘って均一にガスを供給するようにすると共に、集電距
離を最短にするために供給溝間隔を小さくすることが考
えられる。しかし、一体構造のガスセパレータの場合、
工作上の限界から、従来では１mmピッチが限度であり、
また、ガスの流れのコントロールを加味した構造を得る
ことができないという問題がある。また、上述したよう
にガス供給溝の間に冷却水溝を有する構造のセパレータ
は、供給溝間隔が小さいためシール部が少なく、ガス供
給部と冷却水供給部とのシールができないという問題が
ある。さらに、ガスセパレータ中に冷却機構を設けると
肉厚を大きくする必要があり、コンパクト化が阻害され
る。On the other hand, in order to obtain the function of the gas separator described above, the gas supply groove for supplying gas to the gas diffusion electrode is made as small as possible so that the gas is supplied uniformly over the entire surface of the gas diffusion electrode. In addition, it is conceivable to reduce the interval between the supply grooves in order to minimize the current collecting distance. However, in the case of an integrated gas separator,
Conventionally, the 1mm pitch is the limit due to the limit of work,
In addition, there is a problem that it is not possible to obtain a structure that takes into account the control of the gas flow. Further, as described above, the separator having a structure in which the cooling water grooves are provided between the gas supply grooves has a problem that the gap between the supply grooves is small, so that the number of seal portions is small, and the gas supply portion and the cooling water supply portion cannot be sealed. . Further, if a cooling mechanism is provided in the gas separator, it is necessary to increase the wall thickness, which hinders downsizing.
【０００９】本発明はこのような事情に鑑み、コンパク
ト且つ高性能であり、燃料電池のコンパクト化及び性能
向上を図ることができる燃料電池用ガスセパレータを提
供することを目的とする。In view of such circumstances, an object of the present invention is to provide a gas separator for a fuel cell which is compact and has a high performance and which can make the fuel cell compact and improve its performance.
【００１０】[0010]
【課題を解決するための手段】前記目的を達成する本発
明の燃料電池用ガスセパレータは、燃料電池のガス拡散
電極間に挾持されて一方側のガス拡散電極へ燃料ガスを
他方側のガス拡散電極へ酸化剤ガスを供給するためのガ
スセパレータであって、 一方側のガス拡散電極と接触
する一面に燃料ガスを流通するための燃料ガス供給溝が
エッチングにより形成され、厚さが１ｍｍ程度のステン
レス鋼又は銅製の燃料ガス供給板と、他方側のガス拡散
電極と接触する一面に酸化剤ガスを流通するための酸化
剤ガス供給溝がエッチングにより形成された、厚さが１
ｍｍ程度のステンレス鋼又は銅製の酸化剤ガス供給板
と、これら燃料ガス供給板及び酸化剤ガス供給板のそれ
ぞれの他面に接触した状態で冷却水を流通するための冷
却水供給溝がエッチングにより形成され、厚さが0.５ｍ
ｍ程度のステンレス鋼又は銅製の冷却水板とを接合一体
化してなることを特徴とする。A gas separator for a fuel cell according to the present invention, which achieves the above object, is sandwiched between gas diffusion electrodes of a fuel cell and diffuses fuel gas to one gas diffusion electrode on the other side. A gas separator for supplying an oxidizing gas to the electrode, wherein a fuel gas supply groove for flowing a fuel gas is formed by etching on one surface in contact with the gas diffusion electrode on one side, and has a thickness of about 1 mm. Stainless
And less steel or copper fuel gas supply plate, the other side oxidizing gas supplying groove for flowing the oxidizing agent gas to the one surface in contact with the gas diffusion electrode is formed by etching a thickness of 1
The oxidizing gas supply plate made of stainless steel or copper of about mm, and the cooling water supply groove for flowing the cooling water in a state of being in contact with the other surfaces of the fuel gas supply plate and the oxidizing gas supply plate by etching. Formed , 0.5m thick
m and a cooling water plate made of stainless steel or copper .
【００１１】[0011]
【作用】前記構成の燃料電池用ガスセパレータは、冷却
水板の両側に燃料ガス供給板及び酸化剤ガス供給板を接
合したものであり、三者を個々に加工できるので、それ
ぞれ薄板とすることができ、且つエッチング等の微細加
工による供給溝の細分化を図ると共に任意の溝形状が得
ることができる。したがって、コンパクト化を図ること
ができる。また、燃料ガスと酸化剤ガスとの完全な分離
ができ、しかも、供給の均一化と集電効率の向上による
高性能化を図ることができる。The gas separator for a fuel cell having the above-mentioned structure is obtained by joining a fuel gas supply plate and an oxidizing gas supply plate to both sides of a cooling water plate, and the three members can be individually processed. In addition, the supply groove can be subdivided by fine processing such as etching, and an arbitrary groove shape can be obtained. Therefore, compactness can be achieved. Further, the fuel gas and the oxidizing gas can be completely separated, and moreover, the performance can be improved by making the supply uniform and improving the current collection efficiency.
【００１２】[0012]
【実施例】以下、本発明を実施例に基づいて説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.
【００１３】図１には一実施例に係る燃料電池用ガスセ
パレータの分解斜視図、図２にはそのＡ部拡大図、図３
には各部品の表裏の平面及び製造工程を示す。FIG. 1 is an exploded perspective view of a gas separator for a fuel cell according to one embodiment, FIG.
Shows the front and back planes of each part and the manufacturing process.
【００１４】これらの図面に示すように、本実施例のガ
スセパレータ１０は、燃料ガス供給板２０、冷却水板３
０及び酸化剤ガス供給板４０を接合一体化したものであ
る。このガスセパレータ１０の四隅には厚さ方向に貫通
する燃料ガス供給孔１１、酸化剤ガス供給孔１２、燃料
ガス排出孔１３、酸化剤ガス排出孔１４が設けられてお
り、燃料ガス供給孔１１と燃料ガス排出孔１３、及び酸
化剤ガス供給孔１２と酸化剤ガス排出孔１４は、それぞ
れ対角位置に配されており、また、各排出孔１３，１４
の間及び各供給孔１１，１２の間、すなわち幅方向中央
部には、同様に厚さ方向に貫通する冷却水供給孔１５及
び冷却水排出孔１６がそれぞれ設けられている。As shown in these drawings, the gas separator 10 of the present embodiment comprises a fuel gas supply plate 20, a cooling water plate 3.
0 and the oxidizing gas supply plate 40 are joined and integrated. The four corners of the gas separator 10 are provided with a fuel gas supply hole 11, an oxidant gas supply hole 12, a fuel gas discharge hole 13, and an oxidant gas discharge hole 14 penetrating in the thickness direction. The fuel gas discharge holes 13 and the oxidizing gas supply holes 12 and the oxidizing gas discharge holes 14 are respectively arranged at diagonal positions.
Similarly, a cooling water supply hole 15 and a cooling water discharge hole 16 are also provided between the supply holes 11 and 12, that is, at the center in the width direction.
【００１５】燃料ガス供給板２０の表面には、幅方向
（図３中、上下方向）に延びる燃料ガス供給溝２１が多
数一定ピッチで形成されている。また、燃料ガス供給板
２０の裏面の幅方向両端部には、上記燃料ガス供給溝２
１の両端部に対応する位置に該燃料ガス供給溝２１と直
交する方向に延びる複数本の溝からなる燃料ガス供給ヘ
ッダ２２及び燃料ガス排出ヘッダ２３が形成されてい
る。これら燃料ガス供給ヘッダ２２及び燃料ガス排出ヘ
ッダ２３は、図２に示すように、その底側で燃料ガス供
給溝２１と連通している。また、燃料ガス供給ヘッダ２
２はその一端で燃料ガス供給孔１１と、燃料ガス排出ヘ
ッダ２３はその一端で燃料ガス排出孔１３と、それぞれ
連通している。さらに、燃料ガス供給板２０の裏面の長
手方向（図３の左右方向）両端部には、それぞれ冷却水
供給孔１５及び冷却水排出孔１６と連通する複数本の溝
からなる冷却水供給ヘッダ２４及び冷却水排出ヘッダ２
５が形成されている。On the surface of the fuel gas supply plate 20, a number of fuel gas supply grooves 21 extending in the width direction (vertical direction in FIG. 3) are formed at a constant pitch. The fuel gas supply groove 20 is provided at both ends in the width direction of the back surface of the fuel gas supply plate 20.
A fuel gas supply header 22 and a fuel gas discharge header 23 are formed at positions corresponding to both ends of the fuel gas supply groove 21 and include a plurality of grooves extending in a direction orthogonal to the fuel gas supply groove 21. As shown in FIG. 2, the fuel gas supply header 22 and the fuel gas discharge header 23 communicate with the fuel gas supply groove 21 on the bottom side. Also, the fuel gas supply header 2
Reference numeral 2 denotes a fuel gas supply hole 11 at one end thereof, and a fuel gas discharge header 23 communicates with the fuel gas discharge hole 13 at one end thereof. Further, a cooling water supply header 24 composed of a plurality of grooves communicating with the cooling water supply holes 15 and the cooling water discharge holes 16 is provided at both ends in the longitudinal direction (left and right directions in FIG. 3) of the back surface of the fuel gas supply plate 20. And cooling water discharge header 2
5 are formed.
【００１６】酸化剤ガス供給板４０は、燃料ガス供給板
２０と同様な構造をしており、表面には酸化剤ガス供給
溝が形成されると共に、裏面には酸化剤ガス供給ヘッダ
４２、酸化剤ガス排出ヘッダ４３、冷却水供給ヘッダ４
４及び冷却水供給ヘッダ４５がそれぞれ形成されてい
る。そして、酸化剤ガス供給溝と酸化剤ガス供給ヘッダ
４２及び酸化剤ガス排出ヘッダ４３とはそれぞれ底部で
連通しており、また、酸化剤ガス供給ヘッダ４２と酸化
剤ガス供給孔１２、酸化剤ガス排出ヘッダ４３と酸化剤
ガス排出孔１４、冷却水供給ヘッダ４４と冷却水供給孔
１５、冷却水排出ヘッダ４５と冷却水排出孔１６とがそ
れぞれ連通している。The oxidant gas supply plate 40 has the same structure as the fuel gas supply plate 20, and has an oxidant gas supply groove formed on the front surface and an oxidant gas supply header 42 on the back surface. Agent gas discharge header 43, cooling water supply header 4
4 and a cooling water supply header 45 are formed respectively. The oxidizing gas supply groove, the oxidizing gas supply header 42, and the oxidizing gas discharge header 43 communicate with each other at the bottom, and the oxidizing gas supply header 42, the oxidizing gas supply hole 12, and the oxidizing gas supply header. The discharge header 43 communicates with the oxidant gas discharge hole 14, the cooling water supply header 44 communicates with the cooling water supply hole 15, and the cooling water discharge header 45 communicates with the cooling water discharge hole 16, respectively.
【００１７】また、冷却水板３０には、長手方向（図３
中左右方向）に延びると共に厚さ方向に貫通する冷却水
溝３１が形成されている。そして、これら冷却水溝３１
の両端部は、燃料ガス供給板２０及び酸化剤供給板４０
の冷却水供給ヘッダ２４，４４及び冷却水排出ヘッダ２
５，４５と対向している。The cooling water plate 30 has a longitudinal direction (FIG. 3).
A cooling water groove 31 extending in the middle and left and right directions and penetrating in the thickness direction is formed. And these cooling water grooves 31
Both ends of the fuel gas supply plate 20 and the oxidant supply plate 40
Cooling water supply headers 24 and 44 and cooling water discharge header 2
5, 45.
【００１８】本実施例のガスセパレータ１０は、このよ
うな構造の燃料ガス供給板２０及び酸化剤ガス供給板４
０の裏面側で冷却水板３０を挾み、接合したものであ
る。このガスセパレータ１０はガス拡散電極に挾まれた
状態で使用されるものである。そして、燃料ガス供給孔
１１から供給される燃料ガスは、燃料ガス供給ヘッダ２
２から各燃料ガス供給溝２１を流れた後、燃料ガス排出
ヘッダ２３を経由して燃料ガス排出孔１３から排出され
る。また、酸化剤ガス供給孔１２から供給される酸化剤
ガスは、酸化剤ガス供給ヘッダ４２から各酸化剤ガス供
給溝を流れた後、酸化剤ガス排出ヘッダ４３を経由して
酸化剤ガス排出孔１４から排出される。これにより、燃
料ガス供給溝２１及び酸化剤ガス供給溝４１をそれぞれ
流れるガスがガス拡散電極を介して供給されることにな
る。また、冷却水供給孔１５から供給される冷却水は、
冷却水供給ヘッダ２４，４４を介して冷却水溝３１に供
給されて、燃料ガス供給板２０及び酸化剤ガス供給板４
０の裏面に接触して流れた後、冷却水排出ヘッダ２５，
４５を経由して冷却水排出孔１６から排出される。これ
により、燃料ガス供給板２０及び酸化剤ガス供給板４０
を介して燃料電池セルで発生した熱を除去することがで
きる。The gas separator 10 of the present embodiment comprises a fuel gas supply plate 20 and an oxidant gas supply plate 4 having such a structure.
The cooling water plate 30 is sandwiched and joined on the back surface side of the reference numeral 0. The gas separator 10 is used while being sandwiched between gas diffusion electrodes. The fuel gas supplied from the fuel gas supply hole 11 is supplied to the fuel gas supply header 2.
After flowing through each fuel gas supply groove 21 from 2, the fuel gas is discharged from the fuel gas discharge hole 13 via the fuel gas discharge header 23. The oxidizing gas supplied from the oxidizing gas supply hole 12 flows through each oxidizing gas supply groove from the oxidizing gas supply header 42, and then passes through the oxidizing gas discharge header 43. It is discharged from 14. Accordingly, the gas flowing through the fuel gas supply groove 21 and the gas flowing through the oxidant gas supply groove 41 are supplied through the gas diffusion electrode. The cooling water supplied from the cooling water supply hole 15 is
The fuel gas is supplied to the cooling water groove 31 via the cooling water supply headers 24 and 44, and the fuel gas supply plate 20 and the oxidizing gas supply plate 4 are supplied.
After flowing in contact with the back surface of the cooling water discharge header 25,
The cooling water is discharged from the cooling water discharge hole 16 via 45. Thereby, the fuel gas supply plate 20 and the oxidant gas supply plate 40
The heat generated in the fuel cell can be removed via the fuel cell.
【００１９】次に、上述したガスセパレータ１０の具体
的製造例を示す。燃料ガス供給板２０及び酸化剤ガス供
給板４０には、厚さ１mmの純銅板（リン脱酸銅）を用い
た。ガス供給溝２１，４１は０．５mmピッチで０．５mm
の深さとし、裏面のガス供給ヘッダ２２，４２及びガス
排出ヘッダ２３，４３並びに冷却水供給ヘッダ２４，４
４及び冷却水排出ヘッダ２５，４５も０．５mmの深さと
し、ハーフエッチングにより両面同時に加工した。な
お、ガス供給孔１１，１２及びガス排出孔１３，１４並
びに冷却水供給孔１５及び冷却水排出孔１６が貫通する
と共に、ガス供給溝２１，４１とガス供給ヘッダ２２，
４２及びガス排出ヘッダ２３，４３とがそれぞれ連通し
た時点を加工の終点とした。また、冷却水板３０には、
厚さ０．５mmの純銅板を用い、やはりエッチングにより
厚さ方向に貫通するまで加工して冷却水供給溝３１及び
各孔１１〜１６を形成した。次に、冷却水板３０の表裏
面全面に５〜７μＡｇめっきし、これを燃料ガス供給板
２０及び酸化剤ガス供給板４０の裏面側で挾み、真空拡
散溶接装置により一体接合した。この真空拡散接合は、
５×１０-4Torrの真空中で、温度９５０℃、面圧０．１
kg／mm2 で加圧時間３時間保持した後、徐冷することに
より行い、厚さ２．５mmのガスセパレータ１０を得た。Next, a specific example of the production of the gas separator 10 will be described. As the fuel gas supply plate 20 and the oxidant gas supply plate 40, a pure copper plate (phosphorous deoxidized copper) having a thickness of 1 mm was used. Gas supply grooves 21 and 41 are 0.5mm pitch and 0.5mm
Gas supply headers 22, 42 and gas discharge headers 23, 43 and cooling water supply headers 24, 4 on the back surface.
4 and the cooling water discharge headers 25 and 45 were also set to a depth of 0.5 mm, and both surfaces were simultaneously processed by half etching. The gas supply holes 11 and 12 and the gas discharge holes 13 and 14 and the cooling water supply hole 15 and the cooling water discharge hole 16 penetrate, and the gas supply grooves 21 and 41 and the gas supply header 22
The point in time when the 42 and the gas discharge headers 23 and 43 respectively communicated was regarded as the end point of the processing. In addition, the cooling water plate 30 includes
Using a pure copper plate having a thickness of 0.5 mm, processing was performed again by etching until it penetrated in the thickness direction to form a cooling water supply groove 31 and holes 11 to 16. Next, 5 to 7 .mu.Ag plating was applied to the entire front and back surfaces of the cooling water plate 30, sandwiched between the back surfaces of the fuel gas supply plate 20 and the oxidant gas supply plate 40, and integrally joined by a vacuum diffusion welding device. This vacuum diffusion bonding
In a vacuum of 5 × 10 -4 Torr, a temperature of 950 ° C. and a surface pressure of 0.1
After maintaining the pressurizing time at 3 kg / mm 2 for 3 hours, the mixture was gradually cooled to obtain a gas separator 10 having a thickness of 2.5 mm.
【００２０】以上説明したガスセパレータ１０は燃料ガ
ス供給板２０、冷却水板３０及び酸化剤ガス供給板４０
をそれぞれ加工すればよいので、容易に加工でき且つコ
ンパクト化が図れる。また、実施例のようにエッチング
加工を採用すると、溝の大きさ、形状を任意に変化させ
ることができるので、圧損に応じて各溝を拡げたり縮少
したりすることができるので、ガス供給の均一化を図る
ことができる。さらに、かかるガスセパレータは個々に
冷却されるので、燃料電池の反応熱のコントロールが可
能となり、後述するような優れた発電性能を得ることが
できる。また、本発明のセパレータを構成する各溝は、
エッチングにより形成してなるので、薄い板厚であって
も安定した溝深さで容易に加工が可能であると共に、よ
り薄い板を用いることが可能となる。 The gas separator 10 described above includes a fuel gas supply plate 20, a cooling water plate 30, and an oxidizing gas supply plate 40.
Can be easily processed, and can be made compact. In addition, when the etching process is employed as in the embodiment, the size and shape of the groove can be arbitrarily changed, so that each groove can be expanded or contracted according to the pressure loss. Uniformity can be achieved. Further, since such gas separators are individually cooled, the reaction heat of the fuel cell can be controlled, and excellent power generation performance as described later can be obtained. Further, each groove constituting the separator of the present invention,
Since it is formed by etching,
Can be machined easily with a stable groove depth,
A thinner plate can be used.
【００２１】固体高分子電解質膜及び２枚のガス拡散電
極との接合体（以下、セルという）３０枚と、上記セパ
レータ３１枚とを交互に重ね合せて燃料電池とした。こ
の燃料電池に燃料ガスとしてＨ2 （水蒸気加湿）を２．
５kg／cm2 Ｇで３０l／min 、酸化剤ガスとしてＯ
2 ２．５kg／cm2 Ｇ、３０ l／min をそれぞれ供給し、
セル温度７０℃で発電性能を測定した。この結果は図４
に示す。一方、比較のため、従来のガスセパレータとし
て、放電加工の限界である１mmピッチで１mmの深さのガ
ス供給溝を有すると共にガス供給用のガス供給・排出用
ヘッダを板厚方向の中心に設けたもの（厚さ８mm）を用
いて同様の３０枚のセルで燃料電池を構成し、同様に発
電性能を測定した。この場合、冷却は３枚ピッチで水冷
板（厚さ８mm）を設置することにより行った。この結果
も図４に示す。なお、両者の反応面積は１６８cm2 で同
一である。この結果より、本発明のガスセパレータを用
いた燃料電池の方が優れた発電性能が得られることが認
められた。なお、従来型の比較例の燃料電池はセル内で
局部発熱と、反応熱の除去が困難で、運転の安定性に乏
しいので、瞬時のデータである。A fuel cell was obtained by alternately stacking 30 sheets (hereinafter referred to as "cells") of a solid polymer electrolyte membrane and two sheets of gas diffusion electrodes (hereinafter referred to as cells) and 31 sheets of the above separators. This fuel cell is supplied with H 2 (water vapor humidified) as a fuel gas.
30 l / min at 5 kg / cm 2 G, O as oxidizing gas
2 2.5 kg / cm 2 G, 30 l / min respectively,
The power generation performance was measured at a cell temperature of 70 ° C. This result is shown in FIG.
Shown in On the other hand, for comparison, as a conventional gas separator, it has a gas supply groove of 1 mm pitch and 1 mm depth, which is the limit of electric discharge machining, and a gas supply / discharge header for gas supply is provided at the center in the plate thickness direction. A fuel cell was composed of the same 30 cells (thickness: 8 mm), and the power generation performance was measured in the same manner. In this case, cooling was performed by installing a water cooling plate (thickness: 8 mm) at a pitch of three sheets. This result is also shown in FIG. The reaction area of both was 168 cm 2, which was the same. From this result, it was confirmed that the fuel cell using the gas separator of the present invention can obtain more excellent power generation performance. It should be noted that the fuel cell of the conventional comparative example is instantaneous data because it is difficult to remove local heat and reaction heat in the cell and operation stability is poor.
【００２２】また、上述した実施例の燃料電池と比較例
の燃料電池のセル部の寸法を比較した。実施例の燃料電
池は、セル１枚が１．１mmだから、全体の厚さは１．１
×３０＋２．５×３１＝１１０．５mmである。一方、比
較例の燃料電池は、１．１×３０＋８×３１＋８mm×１
０（水冷板）＝３６１mmである。このように、本発明の
ガスセパレータを用いると、燃料電池の著しいコンパク
ト化が実現できる。The dimensions of the cell portions of the fuel cell of the above-described embodiment and the fuel cell of the comparative example were compared. In the fuel cell of the embodiment, since one cell is 1.1 mm, the total thickness is 1.1 mm.
× 30 + 2.5 × 31 = 110.5 mm. On the other hand, the fuel cell of the comparative example was 1.1 × 30 + 8 × 31 + 8 mm × 1
0 (water cooling plate) = 361 mm. Thus, by using the gas separator of the present invention, a remarkable downsizing of the fuel cell can be realized.
【００２３】以上説明した実施例では、セパレータの材
質を純銅としたが、勿論これに限定されず、ステンレス
鋼などを用いてもよい。In the embodiment described above, the material of the separator is pure copper. However, the material is not limited to this, and stainless steel or the like may be used.
【００２４】[0024]
【発明の効果】以上説明したように、本発明のガスセパ
レータは、ガスの均一供給及び集電効率の向上を図るこ
とができると共に、発電に伴なう発熱量のコントロー
ル、運転条件の安定化を図ることができ、しかも燃料電
池を著しくコンパクト化することができる。As described above, the gas separator of the present invention can achieve a uniform supply of gas and an improvement in current collection efficiency, control the amount of heat generated by power generation, and stabilize operating conditions. In addition, the fuel cell can be significantly reduced in size.
【図１】一実施例に係るガスセパレータの分解斜視図で
ある。FIG. 1 is an exploded perspective view of a gas separator according to one embodiment.
【図２】図１のＡ部拡大図である。FIG. 2 is an enlarged view of a portion A in FIG.
【図３】図１のセパレータの部品構造を示す説明図であ
る。FIG. 3 is an explanatory view showing a component structure of the separator of FIG.
【図４】試験結果の電池性能曲線を示すグラフである。FIG. 4 is a graph showing a battery performance curve as a test result.
【図５】固体高分子電解質膜燃料電池を示す構成図であ
る。FIG. 5 is a configuration diagram showing a solid polymer electrolyte membrane fuel cell.
１０ ガスセパレータ １１ 燃料ガス供給孔 １２ 酸化剤ガス供給孔 １３ 燃料ガス排出孔 １４ 酸化剤ガス排出孔 ２０ 燃料ガス供給板 ２１ 燃料ガス供給溝 ２２ 燃料ガス供給ヘッダ ２３ 燃料ガス排出ヘッダ ２４ 冷却水供給ヘッダ ２５ 冷却水排出ヘッダ ３０ 冷却水板 ３１ 冷却水供給溝 ４０ 酸化剤ガス供給板 ４１ 酸化剤ガス供給溝 ４２ 酸化剤ガス供給ヘッダ ４３ 酸化剤ガス排出ヘッダ ４４ 冷却水供給ヘッダ ４５ 冷却水排出ヘッダ DESCRIPTION OF SYMBOLS 10 Gas separator 11 Fuel gas supply hole 12 Oxidant gas supply hole 13 Fuel gas discharge hole 14 Oxidant gas discharge hole 20 Fuel gas supply plate 21 Fuel gas supply groove 22 Fuel gas supply header 23 Fuel gas discharge header 24 Cooling water supply header 25 cooling water discharge header 30 cooling water plate 31 cooling water supply groove 40 oxidant gas supply plate 41 oxidant gas supply groove 42 oxidant gas supply header 43 oxidant gas discharge header 44 cooling water supply header 45 cooling water discharge header
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平１−140559（ＪＰ，Ａ) 特開 昭59−31568（ＪＰ，Ａ) 特開 昭60−236459（ＪＰ，Ａ) 特開 昭60−241658（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H01M 8/00 - 8/24 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-140559 (JP, A) JP-A-59-31568 (JP, A) JP-A-60-236459 (JP, A) JP-A-60-1985 241658 (JP, A) (58) Field surveyed (Int. Cl. 7 , DB name) H01M 8/00-8/24
Claims (1)
て一方側のガス拡散電極へ燃料ガスを他方側のガス拡散
電極へ酸化剤ガスを供給するためのガスセパレータであ
って、 一方側のガス拡散電極と接触する一面に燃料ガ
スを流通するための燃料ガス供給溝がエッチングにより
形成され、厚さが１ｍｍ程度のステンレス鋼又は銅製の
燃料ガス供給板と、 他方側のガス拡散電極と接触する一面に酸化剤ガスを流
通するための酸化剤ガス供給溝がエッチングにより形成
された、厚さが１ｍｍ程度のステンレス鋼又は銅製の酸
化剤ガス供給板と、 これら燃料ガス供給板及び酸化剤ガス供給板のそれぞれ
の他面に接触した状態で冷却水を流通するための冷却水
供給溝がエッチングにより形成され、厚さが0.５ｍｍ程
度のステンレス鋼又は銅製の冷却水板とを接合一体化し
てなることを特徴とする燃料電池用ガスセパレータ。1. A gas separator sandwiched between gas diffusion electrodes of a fuel cell for supplying a fuel gas to one gas diffusion electrode and an oxidizing gas to the other gas diffusion electrode. A fuel gas supply groove for flowing a fuel gas is formed on one surface in contact with the gas diffusion electrode by etching, and a fuel gas supply plate made of stainless steel or copper having a thickness of about 1 mm, and a gas on the other side. An oxidizing gas supply groove for flowing an oxidizing gas on one surface in contact with the diffusion electrode is formed by etching , and a stainless steel or copper oxidizing gas supply plate having a thickness of about 1 mm , A cooling water supply groove for flowing cooling water in a state of being in contact with the other surfaces of the fuel gas supply plate and the oxidizing gas supply plate is formed by etching , and has a thickness of about 0.5 mm.
A gas separator for a fuel cell, comprising a stainless steel or copper cooling water plate joined and integrated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3028339A JP3064023B2 (en) | 1991-02-22 | 1991-02-22 | Gas separator for fuel cells |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3028339A JP3064023B2 (en) | 1991-02-22 | 1991-02-22 | Gas separator for fuel cells |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04267062A JPH04267062A (en) | 1992-09-22 |
| JP3064023B2 true JP3064023B2 (en) | 2000-07-12 |
Family
ID=12245848
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3028339A Expired - Lifetime JP3064023B2 (en) | 1991-02-22 | 1991-02-22 | Gas separator for fuel cells |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3064023B2 (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4234093A1 (en) * | 1992-10-09 | 1994-04-14 | Siemens Ag | Component for installation in a process engineering facility |
| US5776624A (en) * | 1996-12-23 | 1998-07-07 | General Motors Corporation | Brazed bipolar plates for PEM fuel cells |
| US6410178B1 (en) | 1998-05-08 | 2002-06-25 | Aisin Takaoka Co., Ltd. | Separator of fuel cell and method for producing same |
| JP2000100457A (en) | 1998-09-25 | 2000-04-07 | Matsushita Electric Ind Co Ltd | Fuel cell |
| AUPQ078899A0 (en) * | 1999-06-04 | 1999-06-24 | Ceramic Fuel Cells Limited | A fuel cell gas separator |
| DE19953404B4 (en) * | 1999-11-06 | 2004-11-25 | Daimlerchrysler Ag | Electrochemical fuel cell stack |
| US6413664B1 (en) * | 1999-12-23 | 2002-07-02 | Ballard Power Systems Inc. | Fuel cell separator plate with discrete fluid distribution features |
| EP1189297A3 (en) | 2000-09-13 | 2004-04-07 | Mitsui Takeda Chemicals, Inc. | Separator for solid polymer type fuel cell and process for producing the same |
| SE523665C2 (en) * | 2002-09-20 | 2004-05-11 | Volvo Technology Corp | Fuel cell and fuel cell stack |
| CN1507097A (en) * | 2002-12-10 | 2004-06-23 | ��̫ȼ�ϵ�ؿƼ��ɷ�����˾ | Integrated double-plate assembly for fuel cell pack |
| JP4911975B2 (en) | 2003-02-17 | 2012-04-04 | ジャパンコンポジット株式会社 | Conductive resin composition and fuel cell separator |
| JP4486357B2 (en) * | 2003-12-18 | 2010-06-23 | 本田技研工業株式会社 | Fuel cell |
| JP4627406B2 (en) * | 2004-04-02 | 2011-02-09 | 株式会社日立製作所 | Separator and fuel cell |
| JP4899546B2 (en) * | 2006-03-13 | 2012-03-21 | トヨタ自動車株式会社 | Separator and fuel cell |
| JP5082467B2 (en) | 2007-01-29 | 2012-11-28 | トヨタ自動車株式会社 | Fuel cell and separator constituting fuel cell |
| JP5233181B2 (en) | 2007-06-27 | 2013-07-10 | トヨタ自動車株式会社 | Fuel cell |
| WO2014062198A1 (en) | 2012-10-19 | 2014-04-24 | United Technologies Corporation | Low cost fuel cell components |
| CN109216727A (en) * | 2018-08-30 | 2019-01-15 | 威马智慧出行科技（上海）有限公司 | A kind of cooling system of direct methanol fuel cell |
-
1991
- 1991-02-22 JP JP3028339A patent/JP3064023B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04267062A (en) | 1992-09-22 |
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