DE102011114731A1 - Method for drying a fuel cell - Google Patents
Method for drying a fuel cell Download PDFInfo
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- DE102011114731A1 DE102011114731A1 DE102011114731A DE102011114731A DE102011114731A1 DE 102011114731 A1 DE102011114731 A1 DE 102011114731A1 DE 102011114731 A DE102011114731 A DE 102011114731A DE 102011114731 A DE102011114731 A DE 102011114731A DE 102011114731 A1 DE102011114731 A1 DE 102011114731A1
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- fuel cell
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- 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
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- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
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- H01M8/04604—Power, energy, capacity or load
- H01M8/04626—Power, energy, capacity or load of auxiliary devices, e.g. batteries, capacitors
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- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L50/00—Electric propulsion with power supplied within the vehicle
- B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
- B60L50/70—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by fuel cells
- B60L50/72—Constructional details of fuel cells specially adapted for electric vehicles
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- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/40—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for controlling a combination of batteries and fuel cells
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/28—Conjoint control of vehicle sub-units of different type or different function including control of fuel cells
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- H01M16/003—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
- H01M16/006—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers of fuel cells with rechargeable batteries
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- H01M8/18—Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
- H01M8/184—Regeneration by electrochemical means
- H01M8/186—Regeneration by electrochemical means by electrolytic decomposition of the electrolytic solution or the formed water product
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Abstract
Die Erfindung betrifft ein Verfahren zum Trocknen einer Brennstoffzelle (3) in einem Brennstoffzellensystem (1), welches einen elektrischen Energiespeicher (9) umfasst, wobei zum Trocknen der Brennstoffzelle (3) die Brennstoffzelle (3) als Elektrolyseur betrieben wird. Die Erfindung ist dadurch gekennzeichnet, dass der Betrieb der Brennstoffzelle (3) als Elektrolyseur im Stillstand des Brennstoffzellensystems (1) mit elektrischer Leistung aus dem elektrischen Energiespeicher (9) gestartet wird, sobald eine gemessene Temperatur unter einen vorgegebenen Grenzwert fällt.The invention relates to a method for drying a fuel cell (3) in a fuel cell system (1) which comprises an electrical energy store (9), wherein the fuel cell (3) is operated as an electrolyzer for drying the fuel cell (3). The invention is characterized in that the operation of the fuel cell (3) as an electrolyzer at standstill of the fuel cell system (1) with electric power from the electrical energy store (9) is started as soon as a measured temperature falls below a predetermined limit.
Description
Die Erfindung betrifft ein Verfahren zum Trocknen einer Brennstoffzelle mit den im Oberbegriff von Patentanspruch 1 näher definierten Merkmalen. Außerdem betrifft die Erfindung die Verwendung eines solchen Verfahrens.The invention relates to a method for drying a fuel cell with the features defined in greater detail in the preamble of
Brennstoffzellen beziehungsweise Brennstoffzellensysteme sind aus dem allgemeinen Stand der Technik bekannt. Insbesondere beim Einsatz von PEM-Brennstoffzellen ist es allgemein bekannt und üblich, dass diese für einen Start bei Temperaturen unterhalb des Gefrierpunkts während der Abschaltphase getrocknet werden müssen, um ein Einfrieren zu verhindern und für den Wiederstart ideale Bedingungen zu schaffen.Fuel cells or fuel cell systems are known from the general state of the art. In particular, in the use of PEM fuel cells, it is well known and common that they must be dried to start at temperatures below freezing during the shutdown phase to prevent freezing and to create ideal conditions for re-start.
Gängige Trocknungsmethoden nutzen dabei die Wasseraufnahmefähigkeit von trockenem beziehungsweise untersättigtem Gas, beispielsweise von Spülluft, um Wasser in die Dampfphase zu bringen und aus dem Brennstoffzellensystem auszutragen. Ein Nachteil bei dieser Methode ist die Abhängigkeit der Wirksamkeit von der Wasserdampfkurve. Bei niedrigen Temperaturen kann ein unbefeuchtetes oder untersättigtes Gas nur sehr geringe Wasserdampfmengen aufnehmen, bis der Sättigungsdampfdruck erreicht ist. Bei solchen Bedingungen ergibt sich eine kritische Abschalttemperatur, die erreicht werden muss, um den für den Gefrierstart notwendigen Wasserhaushalt sicher einstellen zu können. Um dies zu bewerkstelligen, muss entweder diese kritische Temperatur erzwungen werden, beispielsweise durch einen verzögerten Start oder einen vergleichsweise langen Betrieb nach der Abschaltung des Fahrzeugs, oder es muss ein entsprechend großer Gasstrom eingesetzt werden, was energieintensiv ist und vergleichsweise große Lärmemissionen verursacht. Ein weiterer Nachteil besteht darin, dass nicht vorhersehbar ist, ob ein Brennstoffzellensystem, beispielsweise in einem Fahrzeug, beim nächsten Start eingefroren sein wird oder ob der Start bereits nach so kurzer Zeit oder bei ausreichend hoher Temperatur wieder erfolgt, dass ein Einfrieren nicht zu befürchten ist. Dadurch wird die Brennstoffzelle typischerweise viel zu häufig auf einen Gefrierstart vorbereitet, ohne dass dies notwendig ist. Dies ist mit einem hohen Energie- und Zeitaufwand verbunden und verursacht insbesondere beim Einsatz in einem Fahrzeug häufig unerwünschte Verhaltensweisen für den Fahrer, wie beispielsweise ein langes Nachlaufen des Systems oder dergleichen.Common drying methods use the water absorption capacity of dry or undersatured gas, for example scavenging air, to bring water into the vapor phase and discharge it from the fuel cell system. A disadvantage of this method is the dependence of the effectiveness of the steam curve. At low temperatures, a non-humidified or undersaturated gas can only absorb very small amounts of water vapor until the saturation vapor pressure is reached. In such conditions, a critical shutdown temperature results, which must be achieved in order to set the necessary for the freeze start water balance safely. To accomplish this, either this critical temperature must be enforced, for example, by a delayed start or a comparatively long operation after the shutdown of the vehicle, or it must be a correspondingly large gas flow can be used, which is energy intensive and causes relatively high noise emissions. Another disadvantage is that it is unpredictable whether a fuel cell system, for example in a vehicle, will be frozen at the next start or whether the start takes place again after such a short time or at a sufficiently high temperature that freezing is not to be feared , As a result, the fuel cell is typically prepared for freeze start much too often without this being necessary. This is associated with a high expenditure of energy and time and, in particular when used in a vehicle, frequently causes unwanted behavior for the driver, such as a long run-down of the system or the like.
Aus dem Stand der Technik beispielsweise in Form der
Eine solche Verwendung der Brennstoffzelle als Elektrolyseur lässt sich nun einsetzen, um die Brennstoffzelle beispielsweise nach dem Abstellen der Brennstoffzelle zu trocknen. Hierzu soll auf die
Als Alternative hierzu kann beispielsweise die
Zum weiteren allgemeinen Stand der Technik soll außerdem auf die
Die Aufgabe der hier vorliegenden Erfindung besteht nun darin, ein Verfahren zum Trocknen einer Brennstoffzelle eines Brennstoffzellensystems anzugeben, welches die Brennstoffzelle energieeffizient und schonend auf einen Gefrierstart vorbereitet, ohne dass im Falle eines Gefrierstarts Zeit zum Auftauen des Brennstoffzellensystems verloren geht.The object of the present invention is now to provide a method for drying a fuel cell of a fuel cell system, which prepares the fuel cell energy-efficient and gentle on a freeze start without time is lost in the case of a freeze to thaw the fuel cell system.
Erfindungsgemäß wird diese Aufgabe durch die Merkmale im kennzeichnenden Teil des Anspruchs 1 gelöst. Vorteilhafte Weiterbildungen und Ausgestaltungen des erfindungsgemäßen Verfahrens ergeben sich aus den restlichen hiervon abhängigen Unteransprüchen. Außerdem ist die bevorzugte Verwendung eines solchen Verfahrens angegeben.According to the invention this object is achieved by the features in the characterizing part of
Bei dem erfindungsgemäßen Verfahren ist es vorgesehen, dass der Betrieb der Brennstoffzelle als Elektrolyseur im Stillstand des Brennstoffzellensystems mit elektrischer Leistung aus dem elektrischen Energiespeicher gestartet wird, sobald eine gemessene Temperatur unter einen vorgegebenen Grenzwert fällt. Anders als im Stand der Technik wird das Trocknen der Brennstoffzelle also nicht bei jedem Abstellen des Systems oder erst vor dem Wiederstart gestartet, sondern der Betrieb als Elektrolyseur zum Trocknen der Brennstoffzelle wird temperaturabhängig in der Stillstandsphase des Brennstoffzellensystems gestartet. Damit ist eine Vorkonditionierung des Brennstoffzellensystems auf einen eventuellen Wiederstart unter Gefrierbedingungen möglich. Diese Vorkonditionierung erfolgt in Abhängigkeit der Temperatur immer nur dann, wenn die Temperatur soweit abfällt, dass mit einem weiteren Temperaturabfall zu rechnen ist, welcher zu Bedingungen führt, bei denen das Brennstoffzellensystem über einen Gefrierstart wieder gestartet werden muss. Kommt es dagegen zu keinem Temperaturabfall unter einen kritischen vorgegebenen Temperaturwert, dann verbleibt das Brennstoffzellensystem ohne aufwändiges Trocknen. Somit wird Energie eingespart. Dadurch, dass das Trocknen der Brennstoffzelle nicht unnötig oft erfolgt, werden die Membranen geschont und es lässt sich eine längere Lebensdauer der Brennstoffzelle erzielen. Außerdem kann die zum Trocknen der Brennstoffzelle benötigte Energie über die gesamte Lebensdauer der Brennstoffzelle hinweg entscheidend minimiert werden, da beispielsweise beim Einsatz des Brennstoffzellensystems in einem Fahrzeug in Mitteleuropa lediglich in einigen Monaten des Jahres mit der Notwendigkeit eines Gefrierstarts gerechnet werden muss, während in den anderen Monaten eine solche typischerweise nicht auftritt. Wird das Brennstoffzellensystem nicht jedes Mal für einen solchen Gefrierstart vorbereitet, sondern nur dann aktiv aufgeweckt und auf einen Gefrierstart vorbereitet, wenn die Temperatur unter einen vorgegebenen kritischen Wert fällt, dann kann insgesamt in sehr vielen Fällen auf die energieintensive Vorbereitung auf einen Gefrierstart verzichtet werden. Dennoch kann das Brennstoffzellensystem immer zuverlässig und schnell gestartet werden, egal welche Bedingungen vorliegen.In the method according to the invention, it is provided that the operation of the fuel cell is started as an electrolyzer at standstill of the fuel cell system with electrical power from the electrical energy storage as soon as a measured temperature falls below a predetermined limit. Unlike in the prior art, the drying of the fuel cell is therefore not started every time the system is switched off or before the restart, but the operation as an electrolyzer for drying the fuel cell is started depending on the temperature in the standstill phase of the fuel cell system. This preconditioning of the fuel cell system is possible for a possible restart under freezing conditions. This preconditioning always takes place as a function of the temperature only when the temperature drops so far that a further drop in temperature is expected, which leads to conditions in which the fuel cell system must be restarted via a freeze start. Conversely, if there is no temperature drop below a critical predetermined temperature value, then the fuel cell system remains without elaborate drying. Thus, energy is saved. The fact that the drying of the fuel cell is not unnecessarily often, the membranes are spared and it can achieve a longer life of the fuel cell. In addition, the energy required to dry the fuel cell over the lifetime of the fuel cell can be decisively minimized, since, for example, when using the fuel cell system in a vehicle in Central Europe, the need for a freeze start must be expected only in a few months of the year, while in the other Months such a typically does not occur. If the fuel cell system is not prepared each time for such a freeze start, but only actively woken up and prepared for a freeze start when the temperature falls below a predetermined critical value, then all in all, the energy-intensive preparation for a freeze start can be dispensed with. Nevertheless, the fuel cell system can always be started reliably and quickly, no matter what conditions exist.
Ein weiterer Vorteil der Trocknung der Brennstoffzelle über ihre Verwendung als Elektrolyseur besteht darin, dass keine flüssige Feuchtigkeit aus dem Bereich der Brennstoffzelle ausgetragen werden muss, sondern allenfalls Gase wie Wasserstoff und Sauerstoff sowie aufgrund der Erwärmung der Brennstoffzelle bei ihrer Verwendung als Elektrolyseur gegebenenfalls Wasserdampf. Diese gasförmigen Stoffe lassen sich im Zweifelsfall sehr viel leichter und mit weniger Energieaufwand aus dem Bereich der Brennstoffzelle austragen, als flüssiges Wasser.Another advantage of drying the fuel cell over its use as an electrolyzer is that no liquid moisture must be discharged from the area of the fuel cell, but at best gases such as hydrogen and oxygen as well as due to the heating of the fuel cell when used as an electrolyzer optionally water vapor. In case of doubt, these gaseous substances can be discharged from the area of the fuel cell much more easily and with less energy expenditure than liquid water.
In einer vorteilhaften Weiterbildung des erfindungsgemäßen Verfahrens ist es dabei vorgesehen, dass das Brennstoffzellensystem eine Anodenrezirkulation mit einer Rezirkulationsfördereinrichtung aufweist, wobei die Rezirkulationsfördereinrichtung während des Trocknens der Brennstoffzelle betrieben wird. Die Verwendung einer sogenannten Anodenrezirkulation mit einer Rezirkulationsfördereinrichtung ist bei Brennstoffzellen allgemein bekannt und üblich. Mit einer solchen Anodenrezirkulation werden Abgase aus dem Bereich der Anode abgeführt und über eine Rezirkulationsfördereinrichtung zusammen mit frischem Gas der Anode wieder zugeführt. Dies dient dazu, dass die Anode mit einem Wasserstoffüberschuss betrieben werden kann, um die gesamte zur Verfügung stehende aktive Fläche der Anode im Betrieb ideal auszunutzen. Eine solche Rezirkulationsfördereinrichtung kann dann während des Trocknens der Brennstoffzelle durch ihren Betrieb als Elektrolyseur ebenfalls betrieben werden, um Wasser aus dem Bereich der Anodenrezirkulation in den Anodenraum einzutragen, sodass dieses elektrolysiert werden kann und außerdem Wasserstoff und Wasserdampf gleichmäßig im Bereich der Anodenrezirkulation zu verteilen, um hier möglichst homogene Konzentrationsverhältnisse zu schaffen, welche dann insbesondere für einen Wiederstart des Brennstoffzellensystems von entscheidendem Vorteil sind, da eine Sauerstoff/Wasserstoff-Front, welche über den Katalysator des Anodenraums wandert, allgemein als schädigend betrachtet wird und die Lebensdauer der Brennstoffzelle negativ beeinflusst. Eine solche kann hier vermieden werden.In an advantageous development of the method according to the invention, it is provided that the fuel cell system has an anode recirculation with a recirculation conveyor, wherein the recirculation conveyor is operated during the drying of the fuel cell. The use of so-called anode recirculation with a recirculation conveyor is well known and common in fuel cells. With such an anode recirculation, exhaust gases are removed from the region of the anode and fed back to the anode via a recirculation conveyor together with fresh gas. This is to allow the anode to operate with an excess of hydrogen to make the most of the available active area of the anode during operation. Such a recirculation conveyor can then also be operated during the drying of the fuel cell by its operation as an electrolyzer to enter water from the area of the anode recirculation in the anode compartment, so that it can be electrolyzed and also to distribute hydrogen and water vapor evenly in the field of anode recirculation Here to create the most homogeneous concentration ratios, which are then in particular for a restart of the fuel cell system of decisive advantage, since an oxygen / hydrogen front, which migrates across the catalyst of the anode compartment, is generally considered harmful and negatively affects the life of the fuel cell. Such can be avoided here.
In einer weiteren sehr günstigen und vorteilhaften Ausgestaltung des erfindungsgemäßen Verfahrens ist es außerdem vorgesehen, dass der Betrieb der Brennstoffzelle als Elektrolyseur in Abhängigkeit der Ladekapazität des elektrischen Energiespeichers erfolgt, wobei unterhalb einer vorgegebenen Ladekapazität das Trocknen abgebrochen oder gar nicht erst gestartet wird. Da zum Trocknen typischerweise die Energie des elektrischen Energiespeichers verwendet wird, welcher beispielsweise als Hochvoltbatterie oder durch Kondensatoren mit vergleichbarer Spannung wie die Brennstoffzelle ausgebildet sein kann, ist es notwendig, dass eine ausreichende Ladekapazität des Speichers vorhanden ist, um beispielsweise das System wieder zu starten. Diese darf nicht durch eine Vorkonditionierung und das Trocknen der Brennstoffzelle so weit reduziert werden, dass ein Systemstart später nicht mehr möglich ist. In diesem Fall wird das Trocknen vorsichtshalber abgebrochen oder bei zu geringer Energie in dem elektrischen Energiespeicher gar nicht erst gestartet. Gegenüber dem Trocknen der Brennstoffzelle hat also der Energieerhalt in einer solchen Höhe, dass ein Wiederstart des Brennstoffzellensystems möglich ist, in jedem Fall Vorrang. In a further very favorable and advantageous embodiment of the method according to the invention, it is also provided that the operation of the fuel cell takes place as an electrolyzer depending on the charge capacity of the electrical energy storage, wherein below a predetermined charging capacity, the drying is stopped or not even started. Since the energy of the electric energy storage is typically used for drying, which may be formed, for example, as a high-voltage battery or capacitors with comparable voltage as the fuel cell, it is necessary that a sufficient storage capacity of the memory is present, for example, to restart the system. This must not be reduced to such an extent by preconditioning and drying the fuel cell that it is no longer possible to start the system later. In this case, the drying is canceled as a precaution or not started at too low energy in the electrical energy storage. Compared to the drying of the fuel cell so the energy conservation in such a height that a restart of the fuel cell system is possible, in any case priority.
Das erfindungsgemäße Verfahren ist dabei besonders gut geeignet, um in Brennstoffzellensystemen eingesetzt zu werden, welche häufig Bedingungen ausgesetzt sind, in denen sie bei Temperaturen unterhalb des Gefrierpunkts abgestellt oder nach dem Abstellen bei Temperaturen unterhalb des Gefrierpunkts bis zu einem Wiederstart ausharren müssen. Eine besonders bevorzugte Verwendung ist daher bei Brennstoffzellensystem in Fahrzeugen gegeben, welche über die Brennstoffzellensysteme mit elektrischer Antriebsleistung versorgt werden. Insbesondere bei Fahrzeugen kommt es häufig vor, dass diese abgestellt werden und dass der Wiederstart bei Temperaturen unterhalb des Gefrierpunkts erforderlich ist. Insbesondere dann ist das erfindungsgemäße Verfahren von besonderem Vorteil und kann, anders als die Verfahren gemäß dem Stand der Technik, sehr zeit- und energieoptimiert den Wiederstart des Brennstoffzellensystems beziehungsweise des mit ihm ausgestatteten Fahrzeugs ermöglichen.The inventive method is particularly well suited to be used in fuel cell systems, which are often exposed to conditions in which they must be turned off at temperatures below freezing or must remain after stopping at temperatures below freezing to a restart. A particularly preferred use is therefore given in fuel cell system in vehicles, which are supplied via the fuel cell systems with electric drive power. Especially with vehicles, it often happens that these are turned off and that the restart is required at temperatures below freezing. In particular, the method according to the invention is of particular advantage and, unlike the methods according to the prior art, can enable the re-start of the fuel cell system or of the vehicle equipped with it very time and energy-optimized.
Weitere vorteilhafte Ausgestaltungen des erfindungsgemäßen Verfahrens ergeben sich aus den restlichen abhängigen Ansprüchen und werden anhand des Ausführungsbeispiels deutlich, welches nachfolgend unter Bezugnahme auf die Figur näher beschrieben wird.Further advantageous embodiments of the method according to the invention will become apparent from the remaining dependent claims and will be apparent from the embodiment, which will be described below with reference to the figure.
Die einzige beigefügte Figur zeigt ein beispielhaftes Brennstoffzellensystem in einem Fahrzeug in stark schematisierter Darstellung.The sole attached figure shows an exemplary fuel cell system in a vehicle in a highly schematic representation.
In der Darstellung der einzigen beigefügten Figur ist ein Brennstoffzellensystem
Im regulären Betrieb erzeugt die Brennstoffzelle
Wird das Brennstoffzellensystem
Für den Kathodenraum
Alles in allem entsteht so ein Brennstoffzellensystem
Eine ideale und energieeffiziente Trocknung im Falle, dass die kritische Temperatur unterschritten wird und das Verfahren der Trocknung eingeleitet wird, sollte möglichst die benötigte Feuchtigkeit im Bereich der Membranen zwischen dem Anodenraum
Neben der Verwendung einer Hochvoltbatterie zur Durchführung der Elektrolyse wäre es prinzipiell auch denkbar, eine Niedervoltbatterie, beispielsweise eine Starterbatterie, entsprechend einzusetzen. Die Anzahl der in Elektrolyse betriebenen Zellen müsste dann entsprechend verringert werden oder über eine elektronische Umsetzung der niedrigen Spannung auf ein höheres Spannungsniveau müsste die benötigte Spannung zur Elektrolyse entsprechend bereitgestellt werden.In addition to the use of a high-voltage battery for carrying out the electrolysis, it would also be conceivable, in principle, a low-voltage battery, such as a starter battery accordingly use. The number of cells operated in electrolysis would then have to be correspondingly reduced or via an electronic conversion of the low voltage to a higher voltage level, the required voltage for electrolysis would have to be provided accordingly.
ZITATE ENTHALTEN IN DER BESCHREIBUNG QUOTES INCLUDE IN THE DESCRIPTION
Diese Liste der vom Anmelder aufgeführten Dokumente wurde automatisiert erzeugt und ist ausschließlich zur besseren Information des Lesers aufgenommen. Die Liste ist nicht Bestandteil der deutschen Patent- bzw. Gebrauchsmusteranmeldung. Das DPMA übernimmt keinerlei Haftung für etwaige Fehler oder Auslassungen.This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.
Zitierte PatentliteraturCited patent literature
- US 2003/0068544 A1 [0004] US 2003/0068544 A1 [0004]
- JP 2004-311348 A [0005] JP 2004-311348 A [0005]
- US 2004/0013915 A1 [0006] US 2004/0013915 A1 [0006]
- DE 102007052148 A1 [0007] DE 102007052148 A1 [0007]
Claims (10)
Priority Applications (2)
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DE102011114731A DE102011114731A1 (en) | 2011-10-01 | 2011-10-01 | Method for drying a fuel cell |
PCT/EP2012/003910 WO2013045041A2 (en) | 2011-10-01 | 2012-09-19 | Method for drying a fuel cell |
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DE102011114731A DE102011114731A1 (en) | 2011-10-01 | 2011-10-01 | Method for drying a fuel cell |
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DE102016206495A1 (en) * | 2016-04-18 | 2017-10-19 | Bayerische Motoren Werke Aktiengesellschaft | Motor vehicle and method for operating a motor vehicle |
DE102018205177A1 (en) | 2018-04-06 | 2019-10-10 | Audi Ag | Method for taking into account frost start conditions in a restart of a fuel cell system and apparatus for carrying out the method |
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DE102014215855A1 (en) * | 2014-08-11 | 2016-02-11 | Volkswagen Ag | Method for operating a fuel cell device, fuel cell device and motor vehicle with fuel cell device |
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US20030068544A1 (en) | 2001-10-10 | 2003-04-10 | Alan Cisar | Bifunctional catalytic electrode |
US20040013915A1 (en) | 2001-12-27 | 2004-01-22 | Naoya Matsuoka | Warm-up of fuel cell power plant |
JP2004311348A (en) | 2003-04-10 | 2004-11-04 | Denso Corp | Fuel cell system |
DE102007052148A1 (en) | 2007-10-31 | 2009-05-07 | Robert Bosch Gmbh | Method for avoiding gaseous impurity inclusions in at least one gas space of a fuel cell during a standstill time and fuel cell with means for carrying out the method |
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JP2004179086A (en) * | 2002-11-28 | 2004-06-24 | Nissan Motor Co Ltd | Solid polymer fuel cell system and its operation method |
JP4332568B2 (en) * | 2007-04-03 | 2009-09-16 | 本田技研工業株式会社 | Mobile device |
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2011
- 2011-10-01 DE DE102011114731A patent/DE102011114731A1/en not_active Withdrawn
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Patent Citations (4)
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US20030068544A1 (en) | 2001-10-10 | 2003-04-10 | Alan Cisar | Bifunctional catalytic electrode |
US20040013915A1 (en) | 2001-12-27 | 2004-01-22 | Naoya Matsuoka | Warm-up of fuel cell power plant |
JP2004311348A (en) | 2003-04-10 | 2004-11-04 | Denso Corp | Fuel cell system |
DE102007052148A1 (en) | 2007-10-31 | 2009-05-07 | Robert Bosch Gmbh | Method for avoiding gaseous impurity inclusions in at least one gas space of a fuel cell during a standstill time and fuel cell with means for carrying out the method |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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DE102016206495A1 (en) * | 2016-04-18 | 2017-10-19 | Bayerische Motoren Werke Aktiengesellschaft | Motor vehicle and method for operating a motor vehicle |
DE102018205177A1 (en) | 2018-04-06 | 2019-10-10 | Audi Ag | Method for taking into account frost start conditions in a restart of a fuel cell system and apparatus for carrying out the method |
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