JP2541288B2 - How to shut down the fuel cell - Google Patents

How to shut down the fuel cell

Info

Publication number
JP2541288B2
JP2541288B2 JP63168586A JP16858688A JP2541288B2 JP 2541288 B2 JP2541288 B2 JP 2541288B2 JP 63168586 A JP63168586 A JP 63168586A JP 16858688 A JP16858688 A JP 16858688A JP 2541288 B2 JP2541288 B2 JP 2541288B2
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JP
Japan
Prior art keywords
fuel
gas
air
fuel gas
fuel cell
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
Application number
JP63168586A
Other languages
Japanese (ja)
Other versions
JPH0218869A (en
Inventor
友義 鴨下
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fuji Electric Co Ltd
Original Assignee
Fuji Electric Co Ltd
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Publication date
Application filed by Fuji Electric Co Ltd filed Critical Fuji Electric Co Ltd
Priority to JP63168586A priority Critical patent/JP2541288B2/en
Publication of JPH0218869A publication Critical patent/JPH0218869A/en
Application granted granted Critical
Publication of JP2541288B2 publication Critical patent/JP2541288B2/en
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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/043—Processes for controlling fuel cells or fuel cell systems applied during specific periods
    • H01M8/04303—Processes for controlling fuel cells or fuel cell systems applied during specific periods applied during shut-down
    • 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
    • H01M8/04223—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells
    • 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
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/043—Processes for controlling fuel cells or fuel cell systems applied during specific periods
    • 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
    • H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
    • H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
    • H01M8/04097—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants with recycling of the reactants
    • 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

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

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、燃料電池の運転停止時に、燃料電池本体
内部に残留している燃料ガスを不活性ガスに転換可能な
燃料電池の運転停止方法に関する。Description: TECHNICAL FIELD The present invention relates to a method of shutting down a fuel cell, which can convert the fuel gas remaining inside the fuel cell body into an inert gas when the fuel cell is shut down. Regarding

〔従来の技術〕 燃料電池は電解質を挟持した一対の燃料電極と酸化剤
電極とからなる単電池を複数個積層してスタックを構成
し、このスタックに水素を含む燃料ガスおよび空気や酸
素等の酸化剤ガスを供給して発電を行うものであり、こ
の場合に使用する電解質，作動温度の相違によりりん酸
型，アルカリ型，溶融炭酸塩型等各種の燃料電池に分類
される。[Prior Art] A fuel cell is formed by stacking a plurality of unit cells each consisting of a pair of fuel electrodes sandwiching an electrolyte and an oxidizer electrode to form a stack, and a fuel gas containing hydrogen and air, oxygen, etc. The oxidant gas is supplied to generate electric power, and it is classified into various types of fuel cells such as phosphoric acid type, alkaline type, molten carbonate type, etc., depending on the electrolyte used and the operating temperature.

一方、これら燃料電池に対してその起動，停止（緊急
停止も含む）時には、安全操作のために，燃料電池本体
における燃料ガスの供給／排出系統を不活性ガス、例え
ば窒素ガスでガス置換する操作が従来より一般に行われ
ている。すなわち停止状態にある燃料電池を起動する場
合に、燃料電池内部の燃料系統内に空気ないし酸素が残
っている状態で水素リッチな燃料ガスを供給すると爆鳴
気が形成されて爆発が生じる危険性があり、また逆に燃
料電池を停止する場合には燃料電池本体内部に燃料ガス
が残ったまま放置すると燃料電池の内部放電あるいは温
度変化等による燃料ガスの圧力が低下し，系外から空気
が燃料側に侵入して爆鳴気を形成するおそれがあるため
に、前述したガス置換を行って安全を図るようにしてい
る。On the other hand, at the time of starting and stopping (including emergency stop) of these fuel cells, an operation of replacing the fuel gas supply / exhaust system in the fuel cell main body with an inert gas, for example, nitrogen gas, for safe operation. Has been generally practiced. That is, when starting a fuel cell in a stopped state, if hydrogen-rich fuel gas is supplied with air or oxygen remaining in the fuel system inside the fuel cell, detonation may be formed and an explosion may occur. On the contrary, when the fuel cell is stopped, if the fuel gas is left inside the fuel cell body, the pressure of the fuel gas decreases due to internal discharge of the fuel cell or temperature change, and air from outside the system Since there is a possibility that the gas may enter the fuel side to form detonation, the gas replacement described above is performed for safety.

〔発明が解決しようとする課題〕[Problems to be Solved by the Invention]

従来の燃料電池の運転停止方法においては、上記した
ガス置換を行うためには、燃料ガス，酸化剤ガスの供給
／排出系統とは別に不活性ガスを圧力ポンプ等の貯蔵タ
ンク内に貯蔵して管理し、燃料電池の運転起動，停止の
都度貯蔵タンクから燃料電池の反応ガス系統へ供給する
ようにしている。しかしながら、この方式では燃料の管
理とは別に不活性ガスに関して常時より，不活性ガス貯
蔵タンク内のガス残量の監視，予備分を含めた不活性ガ
スの在庫確保，および購入調達等、手間の掛かる管理等
を必要とし、また、特に移動電源設備では大形の不活性
ガス貯蔵タンクを搭載しなければならないため、設備が
大形化するという問題があった。In the conventional method of shutting down the fuel cell, in order to perform the above gas replacement, an inert gas is stored in a storage tank such as a pressure pump separately from the fuel gas / oxidant gas supply / discharge system. The fuel cell is managed and supplied from the storage tank to the reaction gas system of the fuel cell every time the fuel cell is started or stopped. However, in this method, apart from the management of fuel, it is always necessary to monitor the remaining amount of the inert gas in the inert gas storage tank, to secure the inventory of the inert gas including the reserve, and to purchase and procure the inert gas. There is a problem that the equipment becomes large in size because it requires a troublesome management, and in particular, a mobile power supply equipment must be equipped with a large-sized inert gas storage tank.

この発明は上述の問題点を解決し、燃料ガスを不活性
ガスに簡易に転換し、窒素等の不活性ガスを特別に準備
する必要のない燃料電池の運転停止方法を提供すること
にある。SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and provide a method for shutting down a fuel cell, in which fuel gas is easily converted into an inert gas and it is not necessary to prepare an inert gas such as nitrogen.

〔課題を解決するための手段〕[Means for solving the problem]

上記課題は、この発明によれば、 改質器により改質された燃料ガスが，燃料ガス入口
弁，燃料ガス入口管路を順に通って燃料電極に供給さ
れ，燃料オフガスが，燃料オフガス排出管路，燃料オフ
ガス排出弁を順に通って排出され， 空気ブロワァにより酸化剤ガスとしての空気が空気入
口管路を通して空気電極に供給され，空気排出管路を通
して排出される燃料電池本体が、 前記燃料オフガス排出管路と燃料ガス入口管路とをポ
ンプおよび循環管路内弁を介して連結した燃料ガス循環
管路を備えてなり、さらに， 前記燃料ガス循環管路内における燃料オフガス排出管路
とポンプとの間に、空気導入口弁を有する空気導入口を
備えた燃料電池の運転停止方法において、 運転停止時に，前記燃料オフガス排出弁と燃料ガス入口
弁とを閉じ，燃料電池内に残留している燃料ガスを前記
燃料ガス循環管路にて循環させ、前記燃料ガス循環管路
における空気導入口との連結点の圧力が大気圧より低く
なる所定時間後に，燃料ガス循環管路が備える空気導入
口弁を開いて空気を該燃料ガス循環管路内に導入し、燃
料電池の電極触媒燃焼反応により燃料ガス循環管路内の
ガスに含まれる可燃性ガス成分を低減して、燃料ガスを
不活性ガスに転換することにより達成される。According to the present invention, the fuel gas reformed by the reformer is supplied to the fuel electrode through the fuel gas inlet valve and the fuel gas inlet pipe in this order, and the fuel off gas is discharged into the fuel off gas discharge pipe. And the fuel off-gas discharge valve are sequentially discharged, and air as an oxidant gas is supplied to the air electrode through the air inlet pipe by the air blower and discharged through the air discharge pipe. A fuel gas circulation pipeline connecting the discharge pipeline and the fuel gas inlet pipeline via a pump and a valve in the circulation pipeline; and a fuel off-gas discharge pipeline and a pump in the fuel gas circulation pipeline. In the method of shutting down a fuel cell having an air inlet having an air inlet valve, the fuel off gas discharge valve and the fuel gas inlet valve are closed at the time of shutting down. The fuel gas remaining in the pond is circulated in the fuel gas circulation pipe, and after a predetermined time when the pressure at the connection point with the air introduction port in the fuel gas circulation pipe becomes lower than atmospheric pressure, the fuel gas circulation pipe The air inlet valve provided in the passage is opened to introduce air into the fuel gas circulation pipe, and the combustible gas component contained in the gas in the fuel gas circulation pipe is reduced by the electrode catalyst combustion reaction of the fuel cell. , By converting the fuel gas to an inert gas.

〔作用〕[Action]

燃料電池の運転停止時には、燃料電池本体から給電し
ている負荷を遮断し、燃料オフガス排出弁と燃料ガス入
口弁とを閉じて燃料電極への燃料ガスの供給を断ち，燃
料ガス循環管路のポンプを動作させることにより，燃料
電池本体内に残留している燃料ガスを，燃料ガス循環管
路と燃料電極との間で循環させる。このガスが循環して
いる状態においては、負荷遮断による電池本体内の温度
低下と，および構造物へのりん酸の付着に伴う微小な内
部放電により燃料ガスが消費されることにより、燃料ガ
ス循環管路内の圧力は全体的に減少してくる。燃料ガス
循環管路における空気導入口との連結点の圧力が大気圧
より低くなる所定時間後に，燃料ガス循環管路が備える
空気導入口弁を開くと、大気と燃料ガス循環管路におけ
る空気導入口との連結点との差圧および空気導入弁の有
する流体抵抗で決まる流量の空気が，燃料ガス循環管路
内に供給される。燃料電池本体の電極触媒燃焼反応によ
り燃料電極内のガスに含まれる可燃性ガス成分が低減
し、燃料電極内の燃料ガスを不活性ガスに転換すること
ができる。上記空気導入口弁は空気流入量を絞るために
設けられているため、絞り量は固定値でよく，流量制御
が可能な調整弁である必要はない。When the fuel cell is out of operation, the load feeding from the fuel cell main body is shut off, the fuel off gas discharge valve and the fuel gas inlet valve are closed to cut off the supply of fuel gas to the fuel electrode, and the fuel gas circulation line By operating the pump, the fuel gas remaining in the fuel cell body is circulated between the fuel gas circulation line and the fuel electrode. When this gas is circulated, the fuel gas is circulated because the temperature inside the battery main body decreases due to load shedding and the fuel gas is consumed by the minute internal discharge that accompanies the adhesion of phosphoric acid to the structure. The pressure in the pipeline decreases overall. When the air introduction port valve provided in the fuel gas circulation pipe is opened after a predetermined time when the pressure at the connection point with the air introduction port in the fuel gas circulation pipe becomes lower than atmospheric pressure, air is introduced into the atmosphere and the fuel gas circulation pipe. Air having a flow rate determined by the pressure difference between the connection point with the port and the fluid resistance of the air introduction valve is supplied into the fuel gas circulation line. The combustible gas component contained in the gas in the fuel electrode is reduced by the electrode catalyst combustion reaction of the fuel cell main body, and the fuel gas in the fuel electrode can be converted into an inert gas. Since the air inlet valve is provided to throttle the amount of inflow of air, the throttle amount may be a fixed value and does not need to be a regulating valve capable of controlling the flow rate.

また、上記の大気と燃料ガス循環管路における空気導
入口との連結点との差圧により導入される空気流入量
は，可燃性ガスの低減量に応じた量であることと，空気
導入口弁を流体抵抗のある程度大きいものを用いて空気
流入量を絞っているので微量であるため、爆鳴気が発生
する条件，即ち、可燃性気体である水素の支燃性気体で
ある酸素に対する体積比が2/1付近に至ることがないこ
とは勿論のこと，爆発範囲内には至らず，したがって爆
鳴気の形成を防止することができる。なお、ポンプを運
転した場合，ポンプ前後に圧力差は生ずるが， この圧力差は燃料ガス循環管路内の流体抵抗によって
生ずる圧力損失を補填するものであり、燃料ガス循環管
路内の圧力分布は燃料ガス循環管路内の循環を所定時間
続けた後もほぼ同一の圧力差を有し、燃料ガス循環管路
内の全体の圧力に変動はない。In addition, the amount of air inflow introduced by the pressure difference between the atmosphere and the connection point of the air introduction port in the fuel gas circulation pipe is an amount corresponding to the reduction amount of combustible gas, and Since the amount of air inflow is restricted by using a valve with a certain amount of fluid resistance to restrict the air inflow, the conditions under which detonation is generated, that is, the volume of hydrogen, which is a flammable gas, with respect to oxygen, which is a combustion-supporting gas It goes without saying that the ratio does not reach around 2/1, but it does not reach within the explosion range, and therefore the formation of detonation can be prevented. When the pump is operated, a pressure difference occurs before and after the pump. This pressure difference compensates for the pressure loss caused by the fluid resistance in the fuel gas circulation pipe, and the pressure distribution in the fuel gas circulation pipe is Has substantially the same pressure difference even after the circulation in the fuel gas circulation pipe is continued for a predetermined time, and there is no fluctuation in the overall pressure in the fuel gas circulation pipe.

〔実施例〕 以下、この発明を実施例に基づいて説明する。第１図
は本願に係る運転停止方法の実施例が適用される燃料電
池の反応ガス系統図を例示するものであり、図において
１は模式的に表したりん酸型の燃料電池本体、11は燃料
電極、12は空気電極、13は電解質を含浸保持したマトリ
ックスである。燃料電極11の燃料ガスの出口にある燃料
オフガス排出管路41と，燃料電極11の入口にある燃料ガ
ス入口管路43との間には循環管路内弁22を介してポンプ
３が接続され、燃料ガス循環管路２が構成されている。
さらに燃料ガス入口管路43には燃料ガス入口弁21を介し
て改質器５が接続され、燃料オフガス排出管路41には燃
料オフガス排出弁23が接続されている。ここで改質器５
は天然ガス，メタノール等の原燃料に水を添加した原料
を水素リッチな燃料ガスに転換するものであり、燃料電
池の運転時には燃料ガス入口弁21を開いて，燃料ガスを
燃料電極11に供給する。一方、空気電極12には空気ブロ
ファ６により酸化剤ガスである例えば空気が供給され
る。[Examples] Hereinafter, the present invention will be described based on Examples. FIG. 1 exemplifies a reaction gas system diagram of a fuel cell to which an embodiment of the shutdown method according to the present application is applied.
1 is a schematic representation of a phosphoric acid type fuel cell body, 11 is a fuel electrode, 12 is an air electrode, and 13 is a matrix impregnated with an electrolyte. The pump 3 is connected between the fuel off-gas discharge conduit 41 at the fuel gas outlet of the fuel electrode 11 and the fuel gas inlet conduit 43 at the inlet of the fuel electrode 11 via the circulation conduit internal valve 22. A fuel gas circulation line 2 is configured.
Further, the reformer 5 is connected to the fuel gas inlet pipe line 43 via the fuel gas inlet valve 21, and the fuel off gas discharge valve 23 is connected to the fuel off gas discharge pipe line 41. Reformer 5 here
Is for converting a raw material such as natural gas or methanol to which water is added into a hydrogen-rich fuel gas. When the fuel cell is operating, the fuel gas inlet valve 21 is opened to supply the fuel gas to the fuel electrode 11. To do. On the other hand, the air electrode 12 is supplied with an oxidant gas such as air by the air broffer 6.

燃料電池の運転時には循環管路内弁22は閉じた状態で
ポンプ３も停止しており、燃料ガスは改質器５から燃料
ガス入口弁21を介して燃料電極11に供給され、一方、空
気ブロワァ６から空気電極12に空気が供給されることに
より燃料電池が発電する。During operation of the fuel cell, the valve 3 in the circulation line is closed and the pump 3 is also stopped, and the fuel gas is supplied from the reformer 5 to the fuel electrode 11 via the fuel gas inlet valve 21, while the air is supplied. When the air is supplied from the blower 6 to the air electrode 12, the fuel cell generates electricity.

燃料電池の運転停止時には、燃料ガス入口弁21および
燃料オフガス排出弁23を閉じ，ポンプ３の動作を開始し
て，燃料電極11中の燃料ガスを燃料ガス循環管路２にて
循環させる。温度変化や内部放電により燃料ガス循環管
路における空気導入口との連結点の圧力が大気圧より低
くなる所定時間後に，燃料ガス循環管路が備える空気導
入口弁24を開いて，空気導入口４より空気が燃料ガス循
環管路２内に入ると、燃料電極11の電極触媒上で燃料ガ
ス中の可燃性ガス成分と酸素とが触媒反応する。この
際，燃料ガス循環管路２には、ポンプ３の吸引圧を含む
大気と燃料ガス循環管路における空気導入口との連結点
との差圧および空気導入弁の有する流体抵抗で決まる流
量の空気、即ち，反応した可燃性ガスと酸素とに見合う
量の空気が導入される。反応した可燃性ガスと酸素とに
見合う量とは、可燃性ガスと酸素との反応;2H2＋O2＝2H
2Oにより反応前後で体積が減少する分量である。また、
空気導入口から導入される空気流量は流体抵抗によって
も変化するため、空気導入口弁の有する流体抵抗をある
程度大きくして導入する空気流量を少なくすることで、
可燃性気体である水素に対する空気の体積比を一定値以
下に常に抑え，可燃性ガス中の酸素分圧を爆発限界以下
とすることが容易に可能となり、又単位時間当たりの反
応量を規則出来るので反応に伴って発生する発熱量も規
制でき、燃料電池本体の冷却系（図示していない）を作
動させておけば容易に発生した熱を除去出来て燃料電池
本体の温度を許容値以下に保つことが可能である。この
ように燃料ガス循環管路２中の可燃性ガスが反応により
消費されて，燃料ガス循環管路２中のガス成分は燃料ガ
ス中に含まれていた二酸化炭素等の不活性ガスおよび大
気から取り入れた空気中の窒素となる。さらに、可燃性
ガスの不活性ガスへの転換が実用上問題ない程度に行わ
れる時間を予め求めておき，その時間経過後にポンプ３
の動作を停止し，循環管路内弁22および空気導入口弁24
を閉じ，燃料電極11を不活性のガスで封止する。When the operation of the fuel cell is stopped, the fuel gas inlet valve 21 and the fuel off gas discharge valve 23 are closed, the operation of the pump 3 is started, and the fuel gas in the fuel electrode 11 is circulated in the fuel gas circulation pipe line 2. After a predetermined time when the pressure at the connection point with the air introduction port in the fuel gas circulation line becomes lower than atmospheric pressure due to temperature change or internal discharge, the air introduction port valve 24 provided in the fuel gas circulation line is opened to open the air introduction port. When air enters into the fuel gas circulation line 2 from 4, the combustible gas component in the fuel gas and oxygen react catalytically on the electrode catalyst of the fuel electrode 11. At this time, the fuel gas circulation line 2 has a flow rate determined by the differential pressure between the atmosphere including the suction pressure of the pump 3 and the connection point between the air introduction port of the fuel gas circulation line and the fluid resistance of the air introduction valve. Air, i.e., an amount of air commensurate with the reacted combustible gas and oxygen is introduced. The amount commensurate with the reacted combustible gas and oxygen means the reaction between the combustible gas and oxygen; 2H 2 + O 2 = 2H
It is the amount by which the volume decreases before and after the reaction due to 2 O. Also,
Since the air flow rate introduced from the air introduction port also changes depending on the fluid resistance, by increasing the fluid resistance of the air introduction port valve to some extent to reduce the air flow rate introduced,
The volume ratio of air to hydrogen, which is a flammable gas, is always kept below a certain value, and it becomes easy to keep the oxygen partial pressure in the flammable gas below the explosion limit, and the reaction amount per unit time can be regulated. Therefore, the amount of heat generated due to the reaction can be regulated, and if the cooling system (not shown) of the fuel cell body is operated, the generated heat can be easily removed and the temperature of the fuel cell body can be kept below the allowable value. It is possible to keep. In this way, the combustible gas in the fuel gas circulation pipeline 2 is consumed by the reaction, and the gas component in the fuel gas circulation pipeline 2 is changed from the inert gas such as carbon dioxide contained in the fuel gas and the atmosphere. It becomes nitrogen in the taken air. Furthermore, the time during which the conversion of the flammable gas to the inert gas is carried out to such an extent that there is no practical problem is obtained in advance, and after that time, the pump 3
Stop the operation of the circulation valve 22 and the air inlet valve 24
Is closed and the fuel electrode 11 is sealed with an inert gas.

〔発明の効果〕〔The invention's effect〕

以上説明したように、この発明によれば 改質器により改質された燃料ガスが，燃料ガス入口
弁，燃料ガス入口管路を順に通って燃料電極に供給さ
れ，燃料オフガスが，燃料オフガス排出管路，燃料オフ
ガス排出弁を順に通って排出され， 空気ブロワァにより酸化剤ガスとしての空気が空気入
口管路を通して空気電極に供給され，空気排出管路を通
して排出される燃料電池本体が、 前記燃料オフガス排出管路と燃料ガス入口管路とをポ
ンプおよび循環管路内弁を介して連結した燃料ガス循環
管路を備えてなり、さらに， 前記燃料ガス循環管路内における燃料オフガス排出管
路とポンプとの間に、空気導入口弁を有する空気導入口
を備えた燃料電池の運転停止方法において、 運転停止時に，前記燃料オフガス排出弁と燃料ガス入
口弁とを閉じ，燃料電池内に残留している燃料ガスを前
記燃料ガス循環管路にて循環させ、前記燃料ガス循環管
路における空気導入口との連結点の圧力が大気圧より低
くなる所定時間後に，燃料ガス循環管路が備える空気導
入口弁を開いて空気を該燃料ガス循環管路内に導入し、
燃料電池の電極触媒燃焼反応により燃料ガス循環管路内
のガスに含まれる可燃性ガス成分を低減して、燃料ガス
を不活性ガスに転換することにより、 従来方式で必要とされていた窒素などの不活性ガスを
使用することなしに燃料電池を安全に停止することが出
来る。また特に移動用燃料電池発電装置では、不活性ガ
スを貯蔵する大型の貯蔵タンクを設けることが不要とな
り装置をコンパクトにでき、さらに不活性ガスの管理も
不要となるので装置の運転管理が簡略化でき、また不活
性ガスを消費することがないので運転コストを低減出来
るという利点が得られる。As described above, according to the present invention, the fuel gas reformed by the reformer is sequentially supplied to the fuel electrode through the fuel gas inlet valve and the fuel gas inlet pipe, and the fuel off gas is discharged from the fuel off gas. The fuel cell body is discharged through the pipe and the fuel off-gas discharge valve in order, air as an oxidant gas is supplied to the air electrode through the air inlet pipe by the air blower, and is discharged through the air discharge pipe. A fuel gas circulation line connecting the offgas discharge line and the fuel gas inlet line via a pump and a valve in the circulation line; and a fuel offgas discharge line in the fuel gas circulation line. A method of shutting down a fuel cell having an air inlet having an air inlet valve between the pump and the pump, wherein the fuel off gas discharge valve and the fuel gas inlet valve are closed at the time of shutting down. The fuel gas remaining in the fuel cell is circulated in the fuel gas circulation line, and after a predetermined time when the pressure at the connection point with the air introduction port in the fuel gas circulation line becomes lower than atmospheric pressure, the fuel gas An air inlet valve provided in the circulation pipe is opened to introduce air into the fuel gas circulation pipe,
The combustible gas components contained in the gas in the fuel gas circulation conduit are reduced by the electrocatalytic combustion reaction of the fuel cell, and the fuel gas is converted to an inert gas, such as nitrogen that was required in the conventional method. It is possible to safely shut down the fuel cell without using the above inert gas. Moreover, especially in the mobile fuel cell power generator, it is not necessary to provide a large storage tank for storing the inert gas, the device can be made compact, and the management of the inert gas is also unnecessary, so the operation management of the device is simplified. In addition, there is an advantage that the operating cost can be reduced because the inert gas is not consumed.

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

第１図は本発明の実施例に係る燃料電池の反応ガス系統
図である。 〔符号の説明〕１ ：燃料電池本体 2:燃料ガス循環管路 3:ポンプ 4:空気導入口 5:改質器 6:空気ブロワァ 11:燃料電極 12:空気電極 13:マトリックス 21:燃料ガス入口弁 22:循環管路内弁 23:燃料オフガス排出弁 24:空気導入口弁 41:燃料オフガス排出管路 43:燃料ガス入口管路 44:空気入口管路FIG. 1 is a reaction gas system diagram of a fuel cell according to an embodiment of the present invention. [Explanation of symbols] 1 : Fuel cell main body 2: Fuel gas circulation line 3: Pump 4: Air inlet 5: Reformer 6: Air blower 11: Fuel electrode 12: Air electrode 13: Matrix 21: Fuel gas inlet Valve 22: Circulation line valve 23: Fuel off-gas discharge valve 24: Air inlet valve 41: Fuel off-gas discharge line 43: Fuel gas inlet line 44: Air inlet line

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】改質器により改質された燃料ガスが，燃料
ガス入口弁，燃料ガス入口管路を順に通って燃料電極に
供給され，燃料オフガスが，燃料オフガス排出管路，燃
料オフガス排出弁を順に通って排出され， 空気ブロワァにより酸化剤ガスとしての空気が空気入口
管路を通して空気電極に供給され，空気排出管路を通し
て排出される燃料電池本体が、 前記燃料オフガス排出管路と燃料ガス入口管路とをポン
プおよび循環管路内弁を介して連結した燃料ガス循環管
路を備えてなり、さらに， 前記燃料ガス循環管路内における燃料オフガス排出管路
とポンプとの間に、空気導入口弁を有する空気導入口を
備えた燃料電池の運転停止方法において、 運転停止時に，前記燃料オフガス排出弁と燃料ガス入口
弁とを閉じ，燃料電池内に残留している燃料ガスを前記
燃料ガス循環管路にて循環させ、前記燃料ガス循環管路
における空気導入口との連結点の圧力が大気圧より低く
なる所定時間後に，燃料ガス循環管路が備える空気導入
口弁を開いて空気を該燃料ガス循環管路内に導入し、燃
料電池の電極触媒燃焼反応により燃料ガス循環管路内の
ガスに含まれる可燃性ガス成分を低減して、燃料ガスを
不活性ガスに転換することを特徴とする燃料電池の運転
停止方法。1. A fuel gas reformed by a reformer is sequentially supplied to a fuel electrode through a fuel gas inlet valve and a fuel gas inlet pipe, and fuel offgas is discharged to a fuel offgas exhaust pipe and fuel offgas exhaust. The fuel cell main body, which is discharged through the valves in sequence, is supplied with air as an oxidant gas by the air blower to the air electrode through the air inlet pipe, and is discharged through the air discharge pipe. A fuel gas circulation pipeline connected to the gas inlet pipeline via a pump and a valve in the circulation pipeline; and further, between the fuel off-gas discharge pipeline and the pump in the fuel gas circulation pipeline, In a method of shutting down a fuel cell having an air inlet having an air inlet valve, the fuel off gas discharge valve and the fuel gas inlet valve are closed at the time of shutting down and remain in the fuel cell. An air introduction port provided in the fuel gas circulation line after a predetermined time period in which the fuel gas is circulated in the fuel gas circulation line and the pressure at the connection point with the air introduction port in the fuel gas circulation line becomes lower than atmospheric pressure. The valve is opened to introduce air into the fuel gas circulation conduit, and the combustible gas component contained in the gas in the fuel gas circulation conduit is reduced by the electrode catalyst combustion reaction of the fuel cell to inactivate the fuel gas. A method of shutting down a fuel cell, characterized by converting to gas.
JP63168586A 1988-07-06 1988-07-06 How to shut down the fuel cell Expired - Lifetime JP2541288B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP63168586A JP2541288B2 (en) 1988-07-06 1988-07-06 How to shut down the fuel cell

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63168586A JP2541288B2 (en) 1988-07-06 1988-07-06 How to shut down the fuel cell

Publications (2)

Publication Number Publication Date
JPH0218869A JPH0218869A (en) 1990-01-23
JP2541288B2 true JP2541288B2 (en) 1996-10-09

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ID=15870804

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008112709A (en) * 2006-10-27 2008-05-15 Hyundai Motor Co Ltd Anode side hydrogen oxygen interface formation suppressing structure of fuel cell electric vehicle

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Publication number Priority date Publication date Assignee Title
EP0331367B1 (en) * 1988-02-29 1993-12-08 Showa Shell Sekiyu Kabushiki Kaisha Liquid crystal compounds having fluoroalkyl radical
FR2816762B1 (en) 2000-11-14 2003-10-03 Air Liquide SAFETY METHOD AND DEVICE FOR STARTING AND STOPPING A FUEL CELL
JP4742444B2 (en) * 2001-04-26 2011-08-10 株式会社エクォス・リサーチ Fuel cell device
JP2003109630A (en) * 2001-09-27 2003-04-11 Equos Research Co Ltd Fuel cell system
JP4417068B2 (en) 2003-10-06 2010-02-17 本田技研工業株式会社 How to stop the fuel cell
JP4633354B2 (en) 2003-12-19 2011-02-16 本田技研工業株式会社 How to stop the fuel cell
JP2006172954A (en) * 2004-12-16 2006-06-29 Equos Research Co Ltd Fuel cell system and trouble detection method of circulation pump in fuel cell system
EP1977469A4 (en) * 2005-12-30 2009-12-02 Utc Power Corp Air bleed through fuel cell fuel recycle loop

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008112709A (en) * 2006-10-27 2008-05-15 Hyundai Motor Co Ltd Anode side hydrogen oxygen interface formation suppressing structure of fuel cell electric vehicle

Also Published As

Publication number Publication date
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