WO2023061986A1

WO2023061986A1 - Fuel cell apparatus

Info

Publication number: WO2023061986A1
Application number: PCT/EP2022/078204
Authority: WO
Inventors: Wadim KAISER; Fabian LEUPOLZ
Original assignee: Ekpo Fuel Cell Technologies Gmbh
Priority date: 2021-10-11
Filing date: 2022-10-11
Publication date: 2023-04-20
Also published as: DE102021126289A1

Abstract

In order to improve a fuel cell apparatus, which comprises at least one fuel cell unit and a pipe system comprising at least one pipe means for a fuel medium, the pipe means for the fuel medium comprises a recirculating pipe which leads from an anode residual fluid outlet of the at least one fuel cell unit to an anode fluid inlet of the at least one fuel cell unit, and the recirculating pipe branches into two parallel-connected pipe portions at a branching point, and the two parallel-connected pipe portions come together again at a joining point of the recirculating pipe, the joining point being disposed relative to a fluid path in the recirculating pipe nearer than the joining point to the anode fluid input, and at least one unit which inhibits the flow on one side is disposed in at least one of the two parallel-connected pipe portions, preferably in each of the two parallel-connected pipe portions, and is designed to at least inhibit a fluid flow flowing in this pipe portion from the joining point.

Description

fuel cell device

The invention relates to a fuel cell device comprising at least one fuel cell unit and a line system.

The object of the invention is to improve a fuel cell device.

According to the invention, this object is achieved in embodiments of the invention in that a fuel cell device comprises at least one fuel cell unit and a line system comprising at least one line device for a fuel medium, the line device for the fuel medium being a recirculation line which runs from an anode residue fluid outlet of the at least one fuel cell unit to an anode fluid inlet of the at least one fuel cell unit, and the recirculation line is designed to branch at a branching point into two line sections connected in parallel and the two line sections connected in parallel come together again at a junction point of the recirculation line, the junction point being closer to the anode fluid inlet than with respect to a fluid path in the recirculation line the branching point is arranged, and in at least one of the two line sections connected in parallel at least one one-sided flow-restricting unit is arranged, which is designed to at least restrict a fluid flow flowing from the junction point in the direction of the branching point in this line section. In particular, in a one-sided flow-restricting unit arranged in one of the two line sections connected in parallel, an inhibited flow direction is oriented from the junction point in the direction of the branch point and a preferred flow direction is oriented from the branch point in the direction of the junction point.

For example, one advantage of the invention can be seen in the fact that the two line sections connected in parallel, in particular their different design, allow fuel medium to be recirculated differently, for example depending on different operating states of the fuel cell device, and the at least one unit that restricts flow on one side in at least one of the two line sections connected in parallel, a reverse flow is at least inhibited, preferably at least approximately completely prevented, i.e. a fluid flow flowing from the junction point in the direction of the branching point and thus counter to the intended flow direction in the recirculation line, which is oriented from the residual anode fluid outlet in the direction of the anode fluid inlet is inhibited, preferably at least approximately completely prevented.

In particular, a backflow of fluid from one of the two line sections connected in parallel from the junction point back to the branching point through the other of the two line sections connected in parallel, in which the one-sided flow-restricting unit is arranged, is at least inhibited, preferably at least approximately, while bypassing the at least one fuel cell unit completely prevented. It is preferably provided that in both of the two parallel line sections at least one one-sided flow-inhibiting unit is arranged, so that in both of the two parallel line sections a backflow of a fluid flow is at least inhibited, preferably at least approximately completely prevented.

Alternatively or additionally, the above-mentioned object is also achieved in embodiments of the invention in a fuel cell device which comprises at least one fuel cell unit and a line system, in which at least one line section of a line of the line system has a one-sided flow-inhibiting unit.

In particular, in the at least one one-sided flow-obstructing unit, an obstructed flow direction and a preferred passage direction opposite to the obstructed flow direction are defined for a fluid flowing through this unit, wherein the one-sided flow-obstructing unit is designed to at least inhibit a fluid flow flowing in the obstructed flow direction, preferably an in the inhibited flow direction flowing fluid flow is formed at least approximately completely suppressing.

In particular, this means that a preferred passage direction is defined in the line section in which the one-sided flow-restricting unit is arranged, in which a fluid flow can flow at least essentially unhindered through the line section, but in the opposite direction a fluid flow is at least inhibited, and flow of a fluid in the line system can thus advantageously be controlled and/or undesired backflows can be at least reduced, preferably at least approximately completely prevented. For example, a one-sided flow-impeding unit is arranged in relation to an intended flow direction, oriented away from an anode residue fluid outlet of the fuel cell unit, behind the anode residue fluid outlet and, for example, in front of an anode residue fluid outlet connection of the fuel cell device, with its restricted flow direction being opposite to the intended flow direction.

For example, a one-sided flow-impeding unit is arranged behind the cathode residual fluid outlet and, for example, in front of a cathode residual fluid drain connection of the fuel cell device in relation to an intended flow direction oriented away from a cathode fluid outlet of the fuel cell unit, with its blocked flow direction being opposite to the intended flow direction to the intended flow direction.

Advantageously, the one-sided flow-restricting unit arranged behind the fluid outlet prevents a fluid mixture from getting into the fuel cell unit via the fluid outlet in the opposite direction to the intended flow direction, in particular due to a negative pressure occurring in the fuel cell unit during chemical conversion.

In some favorable embodiments, a one-sided flow-restricting unit is arranged in a bypass line of the line device for the oxidizing medium that bypasses the fuel cell unit, with the bypass line in particular leading from a supply line for the oxidizing medium to a discharge line for a residual cathode fluid mixture and in particular its blocked flow direction from the discharge line in the direction to the supply line is oriented. Advantageously, at least the risk of a fluid flowing in the bypass line in the opposite direction to the intended flow direction is reduced or such an opposite fluid flow is at least approximately completely prevented.

With regard to an embodiment of the line sections connected in parallel, no further details have been given so far.

In particular, it is provided that a fluid delivery unit is arranged in at least one, preferably in both, of the two line sections connected in parallel. Advantageously, at least one one-sided flow-inhibiting unit is arranged in at least the other, for example in both, of the two line sections connected in parallel.

In particular, the fluid delivery unit is designed to deliver fluid in the line section in the direction of the merging point.

Advantageously, short-circuiting of the fluid delivery unit is prevented by the one-sided flow-inhibiting unit arranged in the other of the two line sections connected in parallel.

Thus, in at least one of the two line sections connected in parallel, it is made possible in a favorable manner to convey fluid through the fluid delivery unit, in particular in the direction of the junction point and further to the anode fluid inlet, and in particular by the line sections arranged at least in the other of the two line sections connected in parallel flow-inhibiting unit a backflow of the pumped fluid from the junction point back to the branch point at least inhibited, preferably at least approximately completely prevented. Advantageously, the line device for the fuel medium comprises at least one supply line for supplying fresh fuel medium.

In particular, a reservoir for fresh fuel medium is provided, which is connected to the at least one supply line and fresh fuel medium can thus be supplied from the reservoir via the supply line.

In favorable embodiments, it is provided that the at least one supply line joins one of the two line sections connected in parallel, in particular at a junction point in one of the two line sections.

In some advantageous embodiments, the at least one, for example exactly one, supply line is combined with one of the two line sections connected in parallel and the other of the two line sections is not combined with a supply line.

Thus, via the supply line and the line section that joins it, fresh fuel medium can be supplied, for example together with fluid, from the recirculation line of the fuel cell unit, and via the other of the two line sections connected in parallel, there is the possibility of the fluid in the recirculation line, in particular depending on an operating state of the fuel cell device to promote bypassing the junction of the supply line with a line section through the recirculation line.

In other advantageous embodiments, it is provided that both of the two line sections connected in parallel are combined with one supply line each. For example, it is provided that the two supply lines have at least one common line section, in particular leading from the reservoir, which divides into at least two separate line sections, and a respective line section of each of the two supply lines merges with one of the two line sections connected in parallel.

For example, the two line sections connected in parallel with their respective supply line and in particular components arranged therein can be designed for different sized fluid volume flows to be passed through, in particular for different sized fluid volume flows comprising the fuel medium supplied from the respective supply line.

In particular, it is provided that the supply line opens into the corresponding line section with which it merges.

Provision is preferably made for a fluid delivery unit, in particular a passive or active fluid delivery unit, to be arranged in at least one of the two line sections connected in parallel.

In some particularly preferred embodiments, it is provided that a fluid delivery unit is arranged in each of the two line sections connected in parallel, for example a passive fluid delivery unit in one of the two line sections and an active fluid delivery unit in the other or a passive fluid delivery unit in both line sections.

Provision is advantageously made for a fluid delivery unit to be arranged in at least one line section of the two line sections connected in parallel, which unites with a supply line, this fluid delivery unit being in particular a passive fluid delivery unit. In some advantageous embodiments, in which both of the two line sections connected in parallel are combined with one feed line each, it is provided that a particularly passive fluid delivery unit is arranged in one of the two line sections and a passive fluid delivery unit is arranged in the other of the two line sections.

In some preferred embodiments, in which both of the two line sections connected in parallel merge with one supply line each, it is provided that a particularly passive fluid delivery unit is arranged in one of the two line sections and an active fluid delivery unit is arranged in the other of the two line sections.

In particular, the passive fluid delivery unit functions without the additional supply of external energy other than the flow of at least one fluid in the passive fluid delivery unit and/or the passive fluid delivery unit does not include any movable, externally driven elements for delivering a fluid.

It is particularly favorable if the in particular passive fluid delivery unit comprises an intake tract in a line section of the two line sections connected in parallel, which unites with a supply line, wherein in particular in the intake tract at least one of the uniting line sections, i.e. in particular from one of the two line sections connected in parallel and/or a fluid is drawn in from the line section of the supply line.

In advantageous embodiments, it is provided that a particularly passive fluid delivery unit comprises an intake tract in which a fluid flowing from one of the merging line sections sucks in fluid as a driving medium from the other of the merging line sections as suction medium. It is preferably provided that the fluid flowing from the supply line, i.e. in particular the fluid mixture comprising fresh fuel medium from the reservoir, uses the fluid from the part of the line section lying between the branching point and the in particular passive fluid delivery unit as the driving medium and thus also the anode residual fluid mixture from the anode residual fluid outlet sucks in as a suction medium.

Advantageously, the inflowing fluid containing the fresh fuel medium is thereby utilized in order to convey the residual anode fluid mixture in the recirculation line to the supply line.

In particular, an actively driven fluid delivery unit functions by supplying external energy and/or an actively driven fluid delivery unit comprises at least one fluid delivery element, driven in particular by the supply of external energy, for delivery of the fluid.

For example, an actively driven fluid delivery unit is a fan or a compressor.

In preferred embodiments, it is provided that a particularly actively driven fluid delivery unit is arranged in the line section of the two line sections connected in parallel, which does not meet with a supply line.

In particular, the fluid can thus be conveyed through the recirculation line from the anode residue fluid outlet to the anode fluid inlet by means of the fluid conveying unit.

Advantageously, it is provided that at least one one-sided flow-inhibiting unit is arranged at least in the line section of the two line sections connected in parallel, which does not meet with a supply line. Advantageously, this ensures that the fresh fuel medium supplied through the supply line does not bypass the at least one fuel cell unit and flows through the line section that does not meet with the supply line into the area around the branching point of the recirculation line, in which, for example, a lower pressure than before the anode fluid inlet prevails .

Some favorable embodiments provide that at least in the line section of the two parallel line sections that does not meet with a supply line, a one-sided flow-inhibiting unit is arranged at least between the branching point and the fluid delivery unit.

In some advantageous embodiments it is provided that at least in the line section of the two line sections connected in parallel, which does not meet with a supply line, a one-sided flow-inhibiting unit is arranged between at least the fluid delivery unit and the junction point.

In advantageous embodiments, it is provided that at least one unilateral flow-restricting unit is arranged in at least one line section of the two line sections connected in parallel, which unites with a supply line.

Advantageously, this prevents fluid which flows through the other line section in the direction of the junction point from being conveyed there, in particular by the corresponding fluid conveying unit, and which is intended for the anode fluid inlet, through the at least one line section which merges with the feed line, bypassing the at least one Fuel cell unit flows back into the area around the branch point of the recirculation line. It is advantageously provided that at least one unidirectional flow-restricting unit is arranged between the branch point and the junction point in at least one line section of the two parallel-connected line sections, which unites with a feed line at a junction point.

In particular, this means that the fluid supplied through the supply line and comprising fuel medium preferably flows in the direction of the junction point and a flow of the same in the direction of the branching point is at least inhibited, preferably at least approximately prevented.

In particular, it is provided that in at least one line section of the two line sections connected in parallel, which merges with a supply line, a one-sided flow-inhibiting unit is arranged between the branching point and the fluid delivery unit in this line section.

For example, in this line section the unit restricting flow on one side also defines a preferred flow direction in which a flow resistance is smaller than in the opposite flow direction and, on the other hand, the fluid conveyed by the fluid delivery unit arranged in this line section is not influenced by the one unit restricting flow on one side.

With regard to the design of the at least one unit that is flow-restricting on one side, no further details have so far been given. The at least one unit which is flow-inhibiting on one side, ie the one unit or one, in particular some, for example all, of several units, preferably has one or more of the features explained below. If several units are provided which are flow-restricting on one side, in some preferred embodiments these are designed at least essentially the same and in other advantageous embodiments are designed differently.

Above and below, the wording that a feature is provided for at least one one-sided flow-restricting unit is to be understood as meaning that this feature is preferably for the one one-sided flow-restricting unit or for one, in particular for some, for example all, of several provided one-side flow-restricting units is provided.

Advantageously, it is provided that, in the case of at least one unit that impedes flow on one side, a flow resistance in an impeded flow direction for a fluid flowing through the unit is at least twice as great, in particular at least ten times as great, as a flow resistance in a preferred passage direction opposite to the impeded flow direction.

In particular, in the case of a one-sided flow-impeding unit arranged in one of the two line sections connected in parallel, the blocked flow direction is oriented from the junction point in the direction of the branching point.

In some preferred embodiments it is provided that, in the case of at least one unit which restricts flow on one side, it is possible for a fluid to flow through in the restricted direction, but this is only possible with a large flow resistance. In some advantageous embodiments it is provided that, in the case of at least one unit which restricts flow on one side, a fluid flowing through in the restricted flow direction is at least approximately completely prevented.

At least approximately complete prevention of a flow is to be understood in particular as meaning that of a volume flow of a fluid flowing in the blocked flow direction, the unit of flowing fluid is at most 15%, preferably at most 10%, in particular at most 5%, advantageously at most 2%, the one-sided flow-inhibiting unit can happen.

In particular, at least one unit that restricts flow on one side has a flow section through which a fluid flowing through the unit flows and which is designed such that a flow resistance for this fluid is greater in the restricted flow direction than in the preferred passage direction.

In some advantageous embodiments, it is provided that, in the case of at least one unit that restricts flow on one side, the flow section is designed asymmetrically in such a way that a flow resistance in the flow section in the blocked flow direction is greater for a fluid flowing through, in particular at least twice as large, in particular at least ten times as large than a flow resistance in the preferred flow direction opposite to the blocked flow direction.

One advantage of this is, for example, that the flow resistances of different magnitudes are realized by the design of the flow section, and this advantageously means that the unit requires little maintenance and/or is less susceptible to damage. In some preferred embodiments, it is provided that at least one unit that restricts flow on one side has a plurality of states and, in particular, can switch between the plurality of states and/or can assume the different of the plurality of states.

Advantageously, the one-sided flow-restricting unit having several states comprises at least one flow-restricting state and at least one flow-releasing state.

In particular, a flow resistance for a fluid flowing through the unit is greater in the flow-limiting state, for example at least twice as great, in particular at least ten times as great, as in the flow-releasing state.

In the flow-releasing state, a fluid can preferably flow at least essentially unhindered through the one-sided flow-restricting unit.

In particular, in the flow-limiting state, a flow through the unit for a fluid is inhibited, for example at least approximately prevented.

For example, it is provided that the at least one one-sided flow-restricting unit having a plurality of states changes and/or assumes its state as a function of at least one influencing factor.

In particular, it is provided that the one-sided flow-restricting unit, which has several states, assumes the at least one flow-restricting state when a fluid is flowing in the restricted flow direction and assumes the at least one flow-releasing state when a fluid is flowing in the preferred flow direction. In advantageous embodiments, it is provided that the at least one influencing factor is one or more parameters of the fluid flowing through the unit and/or the state of the fluid, in particular the flow of the fluid.

For example, the influencing factor is a flow direction of the fluid and/or a flow velocity of the fluid and/or a pressure of the fluid, in particular a dynamic pressure and/or a static pressure of the fluid, and/or a pressure gradient of the fluid, in particular a pressure gradient of the fluid in the flow section of the unit, and/or a change in pressure of the fluid, in particular a change in pressure of the fluid over time.

It is advantageous here, for example, that the one-sided flow-inhibiting unit assumes its corresponding state depending on the fluid and/or the state of the fluid, in particular on the flow of the fluid, and in particular an external controller is not required.

In some preferred embodiments, a controller is provided with which the at least one multi-state single-side flow-restricting unit can be set to a desired state.

For example, the controller puts the one-side flow-restricting unit into a desired state depending on an operating state of the fuel cell device, in particular depending on a low-load operation and/or medium-load operation and/or high-load operation that has been started, for example depending on the power to be provided and/or the current intensity to be provided. which corresponds in particular to the started load operation. In particular, the at least one unit that restricts flow on one side is an actively operable unit in which a desired state can advantageously be set actively by an external controller.

In some advantageous embodiments, it is provided that at least one unit that restricts flow on one side has a movable flow-restricting element.

In particular, an orientation and/or a position and/or a shape of the movable flow-restricting element defines the state in which the one-way flow-restricting unit is.

Thus, depending on the alignment and/or position and/or shape of the movable flow-restricting element, the one-sided flow-restricting unit in particular is flow-restricting for a fluid flowing, in particular in the restricted flow direction, or lets a fluid flowing, in particular in the preferred flow direction, through at least essentially unhindered stream.

In some advantageous embodiments, in the case of at least one unit which is flow-restricting on one side, its movable flow-restricting element is a rigid, movably mounted flow-restricting element.

In particular, the movably mounted flow-restricting element is movably mounted in such a way that in the at least one flow-restricting state the flow-restricting element at least partially, for example at least approximately completely, closes a flow cross section in the flow section of the unit and in the at least one flow-releasing state a flow cross section of the flow section for a flowing fluid releases. In particular, the influencing factor causes a movement of the movably mounted flow-limiting element.

In some advantageous embodiments, the movable flow-limiting element of at least one unit that restricts flow on one side is a flow-limiting element that is at least partially movable, ie, in particular, flexible.

In particular, a shape and/or orientation of the inherently movable flow-restricting element in the at least one flow-restricting state is such that a fluid flow, in particular in the restricted flow direction, is at least inhibited, preferably prevented, since, for example, the flow-restricting element has at least a flow cross-section in the flow section of the unit partially, preferably at least approximately completely, and a shape and/or an alignment of the movable flow-restricting element in the at least one flow-releasing state such that a fluid flow, in particular in the preferred passage direction, is at least essentially not impeded by the flow-restricting element, since, for example, the in the shape and/or orientation of the movable flow-restricting element does not significantly protrude into a flow cross section of the flow section.

In particular, it is provided that at least one unit that restricts flow on one side has two stops between which the movable flow-restriction element can move in different states.

In particular, it is provided that the movable flow-limiting element rests against one of the two stops in the at least one flow-limiting state and rests against the other of the two stops in the at least one flow-releasing state. With regard to a further configuration of the fuel cell device, no further details have so far been given.

Alternatively or additionally, the object on which the invention is based is achieved in advantageous embodiments by a fuel cell device that includes a housing device having a housing for at least one fuel cell unit and a media module, with preferably at least one unit that is flow-restricting on one side, which in particular is one or more of the ones explained above Has features, is arranged in the media module, preferably at one of the locations explained above.

In advantageous embodiments, the media module is an assembly made up of several components, in particular an assembly that cannot be dismantled non-destructively.

In some favorable embodiments, the media module has in particular at least one component and/or at least one subassembly, for example at least some components and/or at least some subassemblies, which are arranged separately from one another.

For example, the media module, in particular with at least one component and/or with at least one subassembly, for example at least essentially with all components and/or with all subassemblies, is integrated in the housing and/or attached to the housing.

Features of the media module explained below are advantageously related to at least one component of the same and/or at least one assembly of the same, which is/are integrated in the housing and/or attached to the housing. In particular, the line system is at least partially formed in the media module, with at least some line sections and/or at least some components of the line devices for the fuel medium and for the oxidizing medium and, for example, line devices for a temperature control medium and/or for ventilation of the housing being formed in the media module .

Provision is preferably made for the recirculation line to be formed at least in sections in the media module, with in particular the two line sections of the recirculation line connected in parallel being formed in the media module at least in sections.

In particular, the branching point and/or the merging point is/are formed in the media module.

Provision is preferably made for at least one line section of the two line sections connected in parallel, which unites with a supply line, to be partially or completely formed in the media module, in particular from the branching point to the meeting point.

Provision is preferably made for the media module to have a fuel medium inlet connection.

In particular, the fuel medium inlet connection is provided so that a reservoir with fresh fuel medium can be connected to it and is connected when the fuel cell device is in a connected operating state.

In particular, at least one feed line section is formed in the media module from the fuel medium inlet connection to a junction point with a line section of the two line sections connected in parallel, which merges with a feed line. Preferably, the in particular passive fluid delivery unit and/or at least one one-sided flow-inhibiting unit is arranged in a line section of the two parallel line sections in the media module that joins with a supply line, in particular as explained above.

In some advantageous embodiments, it is provided that the media module for a line section of the two line sections connected in parallel, which, for example, does not merge with a feed line or, for example, merges with a feed line, has a recirculation outlet connection, to which in the media module a line section leads from the branching point, and has a recirculation inlet connection, from which a line section leads in the media module to the junction point, in particular for connecting an in particular active fluid delivery unit in between.

In particular, this line section is only partially formed in the media module.

In particular, it is provided that the particularly active fluid delivery unit can be connected to the media module for a line section of the two line sections connected in parallel.

In particular, a particularly active fluid delivery unit is provided in a line section of the two line sections connected in parallel between the recirculation outlet connection and the recirculation inlet connection and is therefore provided in particular outside of the media module.

The particularly active fluid delivery unit is favorably connected in one line section of the two line sections connected in parallel with a low-pressure side to the recirculation outlet connection and with a high-pressure side to the recirculation inlet connection. Preferably, at least one unit that restricts flow on one side is arranged in the line section of the two parallel line sections in the media module that does not meet with a supply line, for example between the branching point and the recirculation outlet connection and/or between the recirculation inlet connection and the merging point and/or at the branching point and/or or at the meeting point.

In particular, the media module has an anode exhaust gas connection, via which anode residual fluid mixture can advantageously be drained from the anode side of the at least one fuel cell unit. A drain line section in the media module favorably leads from the anode residual fluid outlet of the fuel cell unit to the anode exhaust gas connection.

In particular, the media module also has connections for the line device for the oxidation medium, in particular an oxidation medium inlet connection connected to a cathode fluid inlet of the fuel cell unit and a cathode residue fluid outlet connection connected to a cathode fluid outlet of the fuel cell unit.

With regard to operating states of the fuel cell device and a design of the same and its components, in particular the fluid delivery units, no further details have been given so far.

In particular, it is possible with the fuel cell device to operate the fuel cell device in different operating states through the design of the recirculation line with two line sections connected in parallel and their configuration, for example the equipment with components, in particular with fluid delivery units. It is advantageous that the configuration in two line sections connected in parallel in different operating states allows the component required for the operating state in one of the two line sections connected in parallel to be operated and a component required for another operating state to be operated in the other of the two line sections connected in parallel and thus does not impair the fluid flow in the recirculation line by the parallel connection, which would be the case, for example, if the components in the line sections connected in parallel were instead arranged one behind the other in one line section.

In particular, at least one low-load operation and/or at least one high-load operation is provided in the fuel cell device and is designed for this purpose.

In particular, the low-load operation of the fuel cell device is an operating range which in particular includes at least the minimum power that can be delivered by the fuel cell device and/or is located in a lower power range of the entire power spectrum of the fuel cell device.

In particular, the high-load operation of the fuel cell device is an operating range of the same, which in particular includes at least the maximum power that can be delivered by the fuel cell device and/or is located in the upper power range of the entire power spectrum of the fuel cell device.

For example, the fuel cell device also has at least medium-load operation, the power range of which is located between the power range of low-load operation and the power range of high-load operation. For example, the fuel cell device is particularly advantageous for high-performance systems in which the fuel cell device is often started up in low-load operation and/or medium-load operation in addition to high-load operation.

In favorable embodiments, it is provided that the active fluid delivery unit is provided and designed for low-load operation of the fuel cell device.

In particular, in low-load operation, in which the fuel cell device is only intended to provide a small amount of electrical energy, the only small amount of fluid required to be conveyed in the recirculation line can be conveyed by the active fluid conveying unit, while for a passive fluid conveying unit, in which, for example, the fresh fuel medium supplied is used as Propellant acts, due to the low fluid flows in the low-load operation could promote at least substantially no amounts of fluid.

In other advantageous embodiments it is provided that a passive fluid delivery unit is provided and designed for low-load operation of the fuel cell device.

This is favorable, for example, since the low-load operation can be run efficiently with the passive fluid delivery unit.

In advantageous embodiments, it is provided that a passive fluid delivery unit is provided and designed for medium-load operation and/or high-load operation of the fuel cell device. This is particularly advantageous because in medium-load operation and/or high-load operation the fluid in the recirculation line is pumped by the passive fluid delivery unit, preferably by the supplied fresh fuel medium as the driving medium, without additional energy being required for the passive fluid delivery unit, so that with the Fuel cell device high efficiency can be achieved.

The provision of the passive fluid delivery unit in one of the two line sections connected in parallel has the particular advantage that components, in particular the active fluid delivery unit, which are required for some operating states of the fuel cell device, can be arranged in the other of the two line sections connected in parallel and thus one of the passive fluid delivery unit funded fluid flow at least not significantly affect.

In some advantageous embodiments, it is provided that the fuel cell device and in particular a passive fluid delivery unit is designed and constructed in such a way that only the passive fluid delivery unit is operated during high-load operation of the fuel cell device.

In particular, the one passive fluid delivery unit is designed and constructed in such a way that it can and delivers a sufficient amount of fluid in the recirculation line during high-load operation of the fuel cell device for high-load operation.

In particular, one advantage of this is that, at least in high-load operation, the required amount of fluid is conveyed through the recirculation line by a passive fluid-conveying unit alone, and in high-load operation no active fluid-conveying unit, which would require additional energy, is required, so that the fuel cell device is highly efficient having. In some favorable embodiments it is provided that an active fluid delivery unit is provided and designed for at least high-load operation and/or medium-load operation.

In some preferred embodiments, it is provided that the fuel cell device and in particular its fluid delivery units is/are designed in such a way that both fluid delivery units, for example both the active and the passive fluid delivery unit or both passive fluid delivery units, are to be operated during high-load operation.

In particular, both fluid delivery units in these embodiments deliver fluid through the recirculation line in high-load operation, with the respective maximum delivery quantity of one of the two fluid delivery units alone not being sufficient to raise the fluid delivery quantity required in high-load operation.

For example, one advantage of this is that because both fluid delivery units deliver fluid in high-load operation, the two fluid delivery units can each be made smaller, since the required amount of fluid in high-load operation is applied jointly by both fluid delivery units, so that the fuel cell device is cheaper due to the correspondingly smaller dimensioned fluid delivery units and/or can be configured to save space and/or weight.

In some advantageous embodiments, it is provided that only one fluid delivery unit, for example the passive or the active fluid delivery unit, is operated in the medium-load operation.

In other advantageous embodiments, it is provided that both fluid delivery units are operated in medium-load operation. In some embodiments of the invention, the underlying object is alternatively or additionally achieved by a vehicle, which is at least partially driven by at least one fuel cell unit, in that the vehicle has a fuel cell device with one or preferably more of the features explained above.

In particular, the advantages explained above in connection with the features are also transferred to the vehicle, with the increase in efficiency and/or weight-saving design of the fuel cell device having a particularly favorable effect on the vehicle, since the range of the vehicle is increased in this way, for example.

For example, the fuel cell device is advantageous for powerful vehicles that are also often driven in a low and/or medium speed range.

In particular, the invention also includes methods for operating a fuel cell device, in particular in different load ranges, as explained above.

Above and below, features that are described as particularly and/or favorably and/or advantageously and/or for example and/or as preferred and/or the like are optional features that represent particularly inventive developments of the basic idea of the invention, but for the fundamental success of the invention are not essential.

Above and below, the wording at least essentially in connection with an indication is to be understood in particular as meaning that technically irrelevant and/or technically caused deviations from the at least essentially stated indication are also included. Above and below, the wording at least approximately in connection with a feature is to be understood in particular as meaning that this feature is at least essentially specified and/or that deviations, for example from the specified value and/or a specified direction, of up to ± 20% , preferably of up to ± 10%, in particular of up to ± 5%, are also included in the at least approximately specified information.

The above description of solutions according to the invention thus includes in particular the various feature combinations defined by the following numbered embodiments:

1. Fuel cell device (100) comprising at least one fuel cell unit (110) and a line system (112) comprising at least one line device (114) for a fuel medium, wherein the line device (114) for the fuel medium has a recirculation line (188) which is connected from an anode residual fluid outlet ( 178) which comprises at least one fuel cell unit (110) leading to an anode fluid inlet (163) which leads to at least one fuel cell unit (110), and the recirculation line (188) is designed to branch off at a branch point (212) into two line sections (214, 216) connected in parallel and the two line sections (214, 216) connected in parallel come together again at a junction point (218) of the recirculation line (188), the junction point (218) being closer to the anode fluid inlet (163) than the branching point (212 ) and wherein in at least one of the two line sections (214, 216) connected in parallel, preferably in both of the two line sections (214, 216) connected in parallel, at least one unit (244, 246) that is flow-restricting on one side is arranged, which unit (244, 246) is arranged from the junction point (218) in Direction to the branch point (212) flowing fluid flow in this line section (214, 216) is formed at least inhibiting. 2. Fuel cell device (100) according to the preceding embodiment, wherein a fluid delivery unit (224, 236) is arranged in at least one of the two line sections (214, 216) connected in parallel and in particular in at least the other of the two line sections (214, 216) connected in parallel at least one unit (244, 246) restricting flow on one side is arranged.

3. Fuel cell device (100) according to one of the preceding embodiments, wherein the line device (114) for the fuel medium comprises at least one supply line (172) for supplying fresh fuel medium, for example from a reservoir (174), and wherein in particular the at least one Supply line (172) combined with one of the two line sections connected in parallel.

4. Fuel cell device (100) according to one of the preceding embodiments, wherein in the line section (214) of the two line sections (214, 216) connected in parallel, which merges with the at least one supply line (172), an in particular passive fluid delivery unit (224, 236') is arranged.

5. Fuel cell device (100) according to one of the preceding embodiments, wherein both of the two parallel-connected line sections (214, 216) each have a supply line (1721,

17211) and that in particular in one of the two line sections (214, 216) a particularly passive fluid delivery unit (224, 236') and in the other of the two line sections (216, 214) a particularly passive or active fluid delivery unit (224, 236' ) is arranged. 6. The fuel cell device (100) according to any one of the preceding embodiments, wherein an in particular passive fluid delivery unit (224, 236') has an intake tract in a line section (214) of the two line sections (214, 216) connected in parallel, which unites with a supply line (172). (226) in which, in particular, a fluid flowing from one of the merging line sections as a driving medium draws in a fluid from the other of the merging line sections as a suction medium.

7. The fuel cell device (100) according to one of the preceding embodiments, wherein a particularly actively driven fluid delivery unit (236) is arranged in a line section (216) of the two line sections (214, 216) connected in parallel, which does not meet with a supply line (172).

8. Fuel cell device (100) according to one of the preceding embodiments, wherein at least one line section (216) of the two line sections (214, 216) connected in parallel, which does not meet with a supply line (172), has at least one unit (244, 246) that is flow-inhibiting on one side is arranged.

9. The fuel cell device (100) according to one of the preceding embodiments, wherein at least in the line section (216) of the two line sections (214, 216) connected in parallel, which does not meet with a supply line (172), at least between the branching point (212) and the fluid delivery unit (236) a unit (244, 246) restricting flow on one side is arranged and/or a unit (244, 246) restricting flow on one side is arranged at least between the fluid delivery unit (236) and the junction point (218). 10. The fuel cell device (100) according to one of the preceding embodiments, wherein at least one unit (244, 246) that restricts flow on one side is arranged in at least one line section (214) of the two line sections (214, 216) connected in parallel, which unites with a supply line (172).

11. The fuel cell device (100) according to one of the preceding embodiments, wherein at least in one line section (214) of the two line sections (214, 216) connected in parallel, which merges with a feed line (172) at a junction point, between the branch point (212) and the At least one unit (244, 246) restricting flow on one side is arranged at the junction point.

12. The fuel cell device (100) according to one of the preceding embodiments, wherein in at least one line section (214) of the two line sections (214, 216) connected in parallel, which merges with a supply line (172), between the branching point (212) and the in particular passive fluid delivery unit (224) at least one unit (244, 246) restricting flow on one side is arranged.

13. The fuel cell device (100) according to any one of the preceding embodiments, wherein in at least one unit (244, 246) which restricts flow on one side, a flow resistance in a restricted flow direction (252) is at least twice as great for a fluid flowing through the unit (244, 246). , in particular at least ten times greater than a flow resistance in a preferred passage direction (254) opposite to the blocked flow direction (252). 14. The fuel cell device (100) according to one of the preceding embodiments, wherein a flow of a fluid in the blocked flow direction (252) is at least approximately completely prevented in at least one unit (244, 246) that restricts flow on one side.

15. The fuel cell device (100) according to one of the preceding embodiments, wherein in at least one unit (244, 246) that restricts flow on one side, a flow section (258) is designed asymmetrically such that a flow resistance in the flow section (258 ) in the blocked flow direction (252) is greater, in particular at least twice as large, in particular at least ten times as large, than a flow resistance in the blocked flow direction (252) opposite the preferred passage direction (254).

16. The fuel cell device (100) according to one of the preceding embodiments, wherein at least one unit (244, 246) that is flow-restricting on one side has a plurality of states, in particular at least one flow-restricting state and at least one flow-releasing state, and in particular depending on at least one influencing factor, this at least one unit that is flow-restricting on one side unit (244,246) changes state and/or assumes.

17. The fuel cell device (100) according to the preceding embodiment, wherein the unit (244, 246) that has multiple states that restricts flow on one side assumes the at least one flow-restricting state when a fluid flows in the restricted flow direction and when a fluid flows in the preferential flow direction (254). takes the at least one flow-enabling state. 18. The fuel cell device (100) according to one of the preceding embodiments, wherein the at least one influencing factor for changing and/or assuming a state of the at least one one-sided flow-restricting unit (244, 246) having a plurality of states is a parameter of the fluid in the unit (244, 246) and /or the state of the fluid, in particular the flow of the fluid, in particular a flow direction of the fluid and/or a flow speed of the fluid and/or a pressure of the fluid and/or a pressure gradient in the fluid and/or a pressure change in the fluid .

19. The fuel cell device (100) according to one of the preceding embodiments, wherein a controller is provided with which the at least one one-sided flow-restricting unit (244, 246) having a plurality of states can be set to a desired state.

20. The fuel cell device (100) according to any one of the preceding embodiments, wherein at least one unit (244, 246) that restricts flow on one side has a movable flow-restriction element (262) and in particular a state of the unit that restricts flow on one side (244, 246) is determined by an orientation and/or a position and /or a shape of the movable flow restriction element (262) is defined.

21. Fuel cell device (100) according to one of the preceding embodiments, wherein the movable flow limiting element (262) of at least one unit (244, 246) which restricts flow on one side is a rigid, movably mounted flow limiting element (262). 22. The fuel cell device (100) according to one of the preceding embodiments, wherein the movable flow limiting element (262) of at least one unit (244, 246) that restricts flow on one side is an inherently at least partially movable flow limiting element (262).

23. Fuel cell device (100) according to one of the preceding embodiments, wherein at least one unit (244, 246) that restricts flow on one side has two stops between which the movable flow restriction element (262) can be positioned and moved in different states.

24. The fuel cell device (100), in particular according to one of the preceding embodiments, wherein this comprises a housing device (280) having a housing (118) for at least one fuel cell unit (110) and a media module (282), a line system (112) being at least partially in is formed in the media module (282) and in particular at least one unit (244, 246) which restricts flow on one side is arranged in the media module (282).

25. The fuel cell device (100) according to one of the preceding embodiments, wherein the recirculation line (188), in particular the two line sections (214, 216) of the recirculation line (188) connected in parallel, is/are formed at least in sections in the media module (282).

26. The fuel cell device (100) according to one of the preceding embodiments, wherein a line section (214) of the two line sections (214, 216) connected in parallel, which merges with a supply line (172), is partially or completely formed in the media module (282). 27. Fuel cell device (100) according to one of the preceding embodiments, wherein the media module (282) has a fuel medium inlet connection (286) and in particular at least one feed line section (288) from the fuel medium inlet connection (286) to a junction point with a line section (214) of the two line sections (214, 216) connected in parallel, which unites with a supply line (172), is formed in the media module (282).

28. The fuel cell device (100) according to any one of the preceding embodiments, wherein the media module (282) has a recirculation outlet connection (292) for one line section (216) of the two line sections (214, 216) connected in parallel, to which a line section (293 ) leads from the branching point (212), and has a recirculation inlet connection (294), from which a line section (295) in the media module (293) leads to the junction point (218), and in particular a particularly active fluid delivery unit (236) for the line section of the two line sections (214, 216) connected in parallel can be connected between the recirculation outlet connection (292) and the recirculation inlet connection (294).

29. Fuel cell device (100) according to one of the preceding embodiments, wherein an active fluid delivery unit (236) is provided and designed for low-load operation (NL) of the fuel cell device.

30. Fuel cell device (100) according to one of the preceding embodiments, wherein a passive fluid delivery unit (224, 236') is provided and designed for low-load operation (NL) of the fuel cell device. 31. Fuel cell device (100) according to one of the preceding embodiments, wherein a passive fluid delivery unit (224, 236') is provided and designed for medium-load operation (ML) and/or high-load operation (HL) of the fuel cell device (100).

32. Fuel cell device (100) according to one of the preceding embodiments, wherein it is designed and constructed in such a way that in high-load operation (HL) of the same only one of the fluid delivery units (224, 236) is to be operated.

33. The fuel cell device (100) according to one of the preceding embodiments, wherein it is designed and constructed in such a way that both fluid delivery units (224, 236) are to be operated during high-load operation.

34. Vehicle which is at least partially driven by at least one fuel cell unit (110), this having a fuel cell device (100) according to one of the preceding embodiments.

Preferred features and configurations and advantages of the invention are the subject of the following detailed description and the graphic representation of an exemplary embodiment and variants thereof.

Show in the drawing:

1 shows a schematic representation of the exemplary embodiment of a fuel cell device; 2 shows a representation of an embodiment of two line sections connected in parallel in a recirculation line of the fuel cell device, with a feed line opening into one of the two line sections;

FIG. 3 shows a representation similar to FIG. 2 of an alternative embodiment; FIG.

FIG. 4 shows a representation similar to FIG. 2 of a further alternative embodiment; FIG.

FIG. 5 shows an illustration of an embodiment similar to that in FIG. 2, but with a supply line opening into both of the two line sections; FIG.

FIG. 6 shows a representation similar to FIG. 5 of an alternative embodiment; FIG.

7 shows a one-sided flow-restricting unit with an asymmetric flow section of the line system;

8 shows an alternative embodiment of a one-sided flow-restricting unit with an asymmetric flow section;

9 shows a one-sided flow-restricting unit with a movably mounted rigid flow-restriction element;

10 shows an alternative embodiment of a one-sided flow-restricting unit with a movably mounted rigid flow-restriction element;

11 shows a one-sided flow-restricting unit with a flow-restriction element that is movable in itself; 12 shows an embodiment of a housing device of the fuel cell device comprising a housing and a media module;

13 shows an illustration of operating states of the fuel cell device in a power P-fluid delivery quantity M diagram, in particular for configurations as in FIGS. 2 to 4;

FIG. 14 shows an operating state diagram similar to that in FIG. 13 with alternatively provided operating states;

FIG. 15 shows an operating state diagram similar to FIG. 13 with alternative operating states.

16 shows an operating state diagram similar to that in FIG. 14, but for alternative operating states, in particular for configurations as in FIGS. 5 and 6;

17 shows an operating state diagram similar to that in FIG. 13, but for alternative operating states, in particular for configurations as in FIGS. 5 and 6; and

18 shows an operating state diagram similar to that in FIG. 15, but for alternative operating states, in particular for configurations as in FIGS. 5 and 6.

An embodiment of a designated 100 as a whole

The fuel cell device comprises at least one fuel cell unit 110 and a line system, designated as a whole by 112, with at least one line device 114 for a fuel medium and one Line device 116 for an oxidizing medium, the line devices 114, 116 being connected to the at least one fuel cell unit 110, as shown schematically and by way of example in FIG.

The fuel cell unit 110 comprises at least one fuel cell element, preferably a plurality of fuel cell elements, which is/are arranged in an interior space 117 of a housing 118, wherein in the one or more fuel cell elements the fuel medium and the oxidizing medium are at least partially chemically converted into a product medium and in particular while electrical energy is provided.

For example, the plurality of fuel elements are arranged one above the other in one or more stacks, in particular in a respective stacking direction, and are connected in series.

For example, in one variant, at least some stacks of fuel elements are also connected in parallel.

For example, a temperature control device 122 is also provided in order to keep the fuel cell unit 110 in a temperature range that is permissible for proper operation of the same.

In particular, temperature control device 122 comprises, as part of line system 112, a line device 124 for a temperature control medium, which has at least one supply line 126 for supplying a temperature control medium to fuel cell unit 110 and a discharge line 128 for discharging the temperature control medium from fuel cell unit 110, with the temperature control medium between the supply line 126 and the discharge line 128 is in heat-exchanging contact with the fuel cell unit 110 . The temperature control device 122 is preferably configured, in particular as a function of an operating state of the fuel cell device 100, for cooling and/or heating the fuel cell unit 110 as required.

The supply line 126 and the discharge line 128 are preferably part of a temperature control circuit.

In addition, the fuel cell device 100 comprises, in particular as part of the line system 112, a line device, designated 134 as a whole, for ventilating the housing 118, which has a ventilation line 136 for supplying a ventilation fluid into the interior 117 of the housing 118 and a ventilation line 138 for discharging the ventilation fluid and in particular others includes fluid components entrained by the aeration fluid, as shown schematically in FIG. 1 by way of example.

The oxidizing medium can be supplied to the at least one fuel cell unit 110 by means of line device 116 for an oxidizing medium, and the oxidizing medium components that are supplied to the at least one fuel cell unit 110 but have not been chemically converted in it can be removed from the at least one fuel cell unit 110 again by means of this line device 116.

When the fuel cell device 110 is operating properly, the oxidizing medium, in particular as part of a cathode fluid mixture, is fed to the at least one fuel cell unit 110 by means of this line device 116 and oxidizing medium portions that have not reacted in the fuel cell unit 110 are removed again. The line device 116 for the oxidizing medium comprises at least one supply line 142 which leads to a cathode side 144 of the fuel cell unit 110 and through which the oxidizing medium is supplied to the fuel cell unit 110, as shown by way of example in FIG.

A cathode fluid mixture, which includes the oxidizing medium, is preferably supplied to the fuel cell unit 110 by means of the supply line 142 , the cathode fluid mixture being a cleaned air mixture from the environment of the fuel cell device 100 , for example.

In particular, the oxidizing medium is oxygen.

In particular, a supply unit 146, preferably with a fluid delivery unit, in particular a blower or a compressor, 148 is arranged in the supply line 142, by means of which the fuel cell unit 110 is supplied with the cathode fluid mixture.

For example, the supply unit 146 sucks in the fluid mixture via a suction line 152 in which a filter 154 for cleaning the sucked-in fluid mixture is preferably arranged and feeds it through the supply line 142 to the fuel cell unit 110 .

In addition, line device 116 for the oxidizing medium has at least one drain line 156, by means of which a residual cathode fluid mixture is drawn from cathode side 144, which in particular contains chemically unreacted oxidizing medium portions and/or at least portions of the product medium formed during the chemical process in fuel cell unit 110 and/or components of the supplied cathode fluid mixture comprises, is discharged. Line device 116 for the oxidizing medium preferably also has a bypass line 157, which connects supply line 142 to drain line 156, with bypass line 157 in particular being connected to supply line 142 downstream of fluid delivery unit 148 in relation to the direction of flow of the cathode fluid mixture in supply line 142. A directional valve 158 is arranged in the supply line 142 at the point at which the bypass line 157 leads away from the supply line 142 in order to lead the cathode fluid mixture either via the supply line 142 to the cathode side 144 or into the bypass line 152 .

The fuel medium can be supplied to the at least one fuel cell unit 110 by means of line device 114 for the fuel medium, and the fuel medium components that have been supplied to the at least one fuel cell unit but have not been chemically converted can be removed from the at least one fuel cell unit 110 again.

When fuel cell device 110 is operating properly, this line device 114 is used to supply the fuel medium, for example as part of an anode fluid mixture, to the at least one fuel cell unit 110 and chemically unreacted fuel medium components in fuel cell unit 110 are removed again.

The line device 114 for the fuel medium comprises at least one supply line 162 which leads to an anode side 164 of the fuel cell unit 110 via an anode fluid inlet 163 and through which a fuel medium can be supplied to the fuel cell unit 110 .

An anode fluid mixture, which comprises the fuel medium, is preferably supplied to the fuel cell unit 110 by means of the supply line 162 .

In particular, the fuel medium is hydrogen. In particular, a supply unit 166 is arranged in the supply line 162 and is connected to a reservoir 174 for the fuel medium via a supply line 172 .

During operation of the fuel cell device, the fuel cell unit 110 is supplied with fuel medium from the reservoir 174 via the feed line 172 and the supply line 162 by means of the supply unit 166 .

In addition, the line device 114 for the fuel medium comprises a discharge line 176 which leads away from the anode side 164 of the fuel cell unit 110 via an anode residual fluid outlet 178 .

In particular, chemically unreacted fuel medium fractions and other fractions of the anode fluid mixture supplied to the anode side 164 and, for example, fractions of the product medium formed during the chemical conversion are discharged from the anode side 164 as residual anode fluid mixture through this discharge line 176 .

The discharge line 176 is preferably at least indirectly connected to the supply line 162 via a connecting line 182 , the connecting line 182 advantageously leading to the supply unit 166 .

For example, where connecting line 182 branches off from discharge line 176, a discharge control unit 184 is provided, by means of which the supply line 162 can be supplied with unreacted, in particular at least a large part, of the residual anode fluid mixture via connecting line 182 and, for example, other components in the residual anode fluid mixture, in particular at least a large part of the anode residue fluid mixture, favorably when the anode residue fluid mixture contains only a small proportion of fuel medium fractions, can be discharged via a drain line 186 . In particular, at least parts of supply line 162 and discharge line 176 and connecting line 182 therefore form a recirculation line 188 for the fuel medium, by means of which at least unreacted fuel medium portions in the residual anode fluid mixture can be fed back to the anode fluid mixture and fed to fuel cell unit 110.

The recirculation line 188 branches, particularly in the area of the supply unit 166, at a branching point 212 into two line sections 214 and 216 connected in parallel, which come together again at a junction point 218, as is shown by way of example in variants in FIGS.

In particular, connecting line 182 leads to branching point 212 and at least a section of supply line 162 leads from junction point 218 to the anode side of the at least one fuel cell unit 110, so that in relation to a fluid path in recirculation line 188 and the correct intended flow direction of the fluid in recirculation line 188 the junction point 212 is located closer to the anode residue fluid outlet 178 than the junction point 218; and the junction point 218 is located closer to the anode fluid inlet 163 than the junction point 212.

In some variants, shown by way of example in Figs. 2 to 4, the supply line 172 opens into one of the line sections 214, 216 connected in parallel, here into line section 214, so that this parallel line section 214 joins the supply line 172 coming from the reservoir 174 united. A preferably passive fluid delivery unit 224 is arranged in this line section 214 , which is connected in parallel and joins the supply line 172 , through which fluid can be delivered in the direction of the junction point 218 and further to the anode fluid inlet 163 .

This fluid delivery unit 224 preferably comprises an intake tract 226, into which fluid flowing from supply line 172, in particular fluid containing fresh fuel medium, flows and in particular expands and, as the driving medium, fluid from that part of line section 214 connected in parallel between branch point 212 and fluid delivery unit 224 thus sucks in particular from the connecting line 182 as a suction medium.

In particular, the preferably passive fluid delivery unit 224 is designed as a jet pump, in particular as an injector.

Preferably, a control valve 228 is also arranged in supply line 172, by means of which the inflow of fluid, in particular fresh fuel medium, from the reservoir, which is in particular under overpressure, is regulated and, for example, a pressure of the fluid comprising the fresh fuel medium can be kept at least approximately constant.

For example, a pressure reducer is also installed between the control valve 228 and the reservoir 174, which regulates the high pressure in the reservoir 174 to a medium pressure, for example in the range between 4 bar and 25 bar. In particular, in the other line section connected in parallel, which does not merge with supply line 172, but only comes together again at junction point 218 with the line section connected in parallel that meets supply line 172, i.e. here in line section 216 connected in parallel, a preferably active fluid delivery unit 236, with which a fluid can be delivered through this line section 216 connected in parallel in the direction of the branch point 212 and thus coming from the connecting line 182 in the direction of the junction point 218 and thus further to the anode fluid inlet 163 and is delivered during operation.

The preferably active fluid delivery unit 236 is favorably an actively driven fluid delivery unit, in particular a compressor or a fan.

Advantageously, in each of the two line sections 214 and 216 connected in parallel there is at least one unit 244 and 246 which restricts flow on one side and is designed in such a way that a flow of a fluid can take place in a restricted flow direction 252, which is in the direction of branching point 212 and further to the connecting line 182 and thus also oriented towards the residual anode fluid outlet, is at least impeded and a fluid flow in a preferred flow direction 254 opposite to the impeded flow direction 252 is preferably allowed to pass through the flow-impeding unit 244, 246 at least essentially unhindered, with the preferred flow direction 254 in the direction is oriented to the junction point 218 and thus in particular in the direction of the anode fluid inlet 163 . Preferably, the one-sided flow-inhibiting unit 244, which is arranged in the parallel line section 214 that meets with the feed line 172, is between the branch point 212 and the fluid delivery unit 224 in this parallel line section 214, and thus between the branch point 212 and the point at which the feed line 172 joins the parallel line section Line section 214 is arranged in this line section 214, as shown by way of example in FIGS.

In some variants, as an alternative or in addition, a unit 244 that is flow-inhibiting on one side is arranged in the parallel-connected line section 214 that joins the supply line 172 between the point where the supply line 172 opens into the parallel-connected line section 214 and/or the fluid delivery unit 224 on the one hand and the junction point 218 on the other /or a one-sided flow-inhibiting unit 244 for this line section 214 connected in parallel, which unites with the supply line 162, is arranged at the junction point 218.

In some variants of the exemplary embodiment, unit 246 that restricts flow on one side is arranged in line section 216, which is connected in parallel and into which supply line 172 does not open, between branching point 212 and fluid delivery unit 236 in this line section 216, as shown by way of example in Fig. 2.

In some variants of the exemplary embodiment, the one-sided flow-inhibiting unit 246 is arranged in the line section 216 connected in parallel, which does not meet with the supply line 172, between the fluid delivery unit 236 and the junction point 218 in this line section 216 connected in parallel, as shown by way of example in Fig. 3 is. In some variants, the one-sided flow-restricting unit 246 for the line section 216 connected in parallel, which does not merge with the feed line 172, is arranged at the junction point 218, as shown by way of example in FIG.

In some variants, in at least one of the two parallel-connected line sections 214, 216, a plurality of units that restrict flow on one side are provided.

In some advantageous variants, both of the two parallel-connected line sections 214' and 216' unite with a respective supply line 1721 and 172II, as shown by way of example for variants in Figs. 5 and 6. In particular, elements or features in these variants that are at least essentially the same and/or fulfill at least essentially the same function as in the variants explained above are given the same reference symbols, and in particular when reference is made to a special configuration in these variants a superscript is added to the reference numerals, and unless otherwise explained below with regard to the design of these features and/or elements, reference is made in full to the above statements.

In particular, the supply lines 1721, II have a common line section connected to the reservoir 174, in which a pressure reducer is preferably installed, and the common line section separates into two line sections, each of which is divided into one of the two line sections 214', 216' connected in parallel. open out and preferably have a respective control valve 2281 and 228II.

A particularly passive fluid delivery unit 224 is preferably arranged in one of the two line sections connected in parallel, here in the line section 114′. In particular, a further fluid delivery unit 236' is also arranged in the other of the two line sections connected in parallel, here in the line section 216'.

In some favorable variants, the further fluid delivery unit 236' in the line section 216' is a passive fluid delivery unit 236', and a one-sided flow-inhibiting unit 246 is advantageously arranged in this line section 216' between the branch point 212 and this fluid delivery unit 236', as shown by way of example in Fig. 5 is shown.

In particular, the two passive fluid delivery units 224 and 236' are dimensioned for different load operations, so that in particular these two fluid delivery units 224 and 236' and, for example, the respective supply line 1721, 172II are designed for different volume flows of the inflowing fluid.

In particular, one of the two passive fluid delivery units 224, 236' is designed for small volume flows, for example at least for low-load operation, so that even a small volume flow of the fluid flowing out of the supply line 1721 is sufficient as a motive medium to draw in fluid from the connecting line 182 as a suction medium.

The additional fluid delivery unit, here for example the fluid delivery unit 236′, is provided for load operation, in particular high-load operation and, for example, medium-load operation, for which the particularly small fluid delivery unit 224 is too small.

In particular, in some variations the further fluid delivery unit 236' is designed such that it can deliver at least the difference between the volume flow required for this load operation, in particular high-load operation, and the maximum volume flow that can be supplied by the fluid delivery unit 224, which in particular has a small design. For example, the two fluid delivery units 224, 236' on their own are too small, at least for high-load operation, but the two fluid delivery units 224, 236' together can deliver enough fluid, i.e. in particular a sufficiently large fluid volume flow with sufficiently fresh and recirculating fuel medium proportions, even for the Promote high-load operation.

For example, in some variations, the further fluid delivery unit 236' is designed to be sufficiently large that it alone can deliver the required volume flow with sufficiently fresh and recirculating fuel medium portions even in high-load operation

In other favorable variants, the fluid delivery unit 236' arranged in the other line section 116' is an active fluid delivery unit 236', as shown by way of example in FIG.

In some favorable variations, the feed line 17211a opens into the line section 216' between the fluid feed unit 236' and the junction point 218, so that advantageously the fluid feed unit 236' does not also have to feed the fluid supplied through the feed line 17211a.

In other favorable variations, supply line 17211b opens into line section 116' between branch point 212 and fluid delivery unit 236', so that the fluid supplied through supply line 17211b is advantageously also sucked in by fluid delivery unit 136' and this supplied fluid and the fluid from the connecting line 182 are already mixed with one another in the fluid delivery unit 136'.

Both variations are shown by way of example in FIG. 6, a supply line 172II advantageously opening into the line section 216' at only one point. In particular, a one-sided flow-inhibiting unit 246 is also arranged in this line section 216', preferably between the branching point 212 on the one hand and at least the junction of the supply line 17211 and/or the fluid delivery unit 236' on the other hand, as shown by way of example in Fig. 6.

In the case of variations, this unit or a further unit 246 restricting flow on one side is arranged at a different point in the line section 216′ as an alternative or in addition, in particular as explained above in connection with the further variants and as an example in FIGS. 3 and 4 is shown.

In particular, this variant also provides that the passive fluid delivery unit 224 in one of the line sections connected in parallel, here in the line section 214', is designed for small volume flows, in particular at least for low-load operation, and the further, here active fluid delivery unit 236', is provided and designed in the other line section 216 ′ for larger required volume flows, for example at least in high-load operation and/or medium-load operation, as was discussed in connection with the variant explained above in variations, and reference is made to these explanations in their entirety.

In favorable variants of the exemplary embodiment, alternatively or additionally, in other and/or further line sections of line system 112, in particular in line sections of line devices 114, 116 for the fuel medium and for the oxidation medium, in which a backflow of a fluid is to be at least inhibited, preferably prevented , a one-sided flow-restricting unit or several one-sided flow-restricting units arranged. For example, in discharge line 176, in particular between residual anode fluid outlet 178 and discharge control unit 184, there is a one-sided flow-inhibiting unit, which allows flow of the residual anode fluid mixture from residual anode fluid outlet 178 to discharge control unit 184 at least essentially unimpeded, but allows reverse flow in the opposite direction to the Anode residual fluid outlet 178 at least inhibits, preferably at least approximately blocked.

For example, alternatively or additionally, a one-sided flow-inhibiting unit is arranged in drain line 156 of line device 116 for the oxidizing medium, for example between a cathode residual fluid outlet on cathode side 144 of the at least one fuel cell unit 110 and the point at which bypass line 157 opens into drain line 156, which unit in particular is one of the Fluid flowing through the cathode residual fluid outlet can flow through at least essentially unhindered, but at least inhibits a fluid flowing in the opposite direction, ie in the direction of the cathode residual fluid outlet, preferably such a fluid flow is at least approximately completely prevented.

For example, in some variants in the bypass line 157 a one-sided flow-inhibiting unit is arranged, which allows a flow of fluid from the supply line 142 to the drain line 156 at least essentially unhindered, but at least inhibits a flow of the fluid in the opposite direction, preferably at least approximately prevents it.

The one-sided flow-impeding units 244, 246 are preferably designed as in one or more of the variants explained below, with the two one-sided flow-impeding units 244, 246 being connected in parallel in some variants of the exemplary embodiment Line sections 214, 216 are of the same design and, in other variants, differently formed one-sided flow-restricting units 244 and 246 are provided in the two line sections 214 and 216 connected in parallel.

In particular, a flow resistance to a fluid flow through a flow section 258 of the unit 244, 246 restricting flow on one side in the blocked flow direction 252 is greater, for example at least twice greater, preferably at least ten times greater, than a flow resistance to a flow in the preferential passage direction 254.

In some variants, the flow section 258 is designed asymmetrically with respect to the blocked flow direction 252 and the preferred passage direction 254 that the flow resistance in the blocked flow direction 252 is greater than the flow resistance in the preferred passage direction 254.

In some favorable variants, the asymmetrically designed flow section 258 has asymmetrical branches, as is realized, for example, in a Tesla valve and is shown by way of example in FIG. 7 .

In particular, a flow of a fluid flowing in the restricted flow direction 252 branches in the branches, and the branched flows impede each other, so that a high flow resistance is generated. In contrast to this, a flow of a fluid flowing in the preferential passage direction 254 flows at least essentially unhindered past the asymmetric branches and essentially unhindered through the asymmetric flow section 258, so that in the preferential passage direction 254 there is at most a low flow resistance for the flow. In some variants, the flow section 258 of the one-sided flow-obstructing unit 244, 246 has, at least in one section, a line cross-section that increases transversely to the blocked flow direction 252, so that the line cross-section in the preferred flow direction 254 becomes smaller, as shown by way of example in Fig. 8.

In particular, during the diverging flow of a fluid flowing in the blocked flow direction 252, a turbulence is formed in the increasing flow section 258, so that a large flow resistance is generated in the blocked flow direction 252, whereas for a fluid flowing in the preferred flow direction 254, the narrowing flow section 258 does can act as a throttle, for example, but has a lower flow resistance in the preferred passage direction 254 than in the blocked flow direction 252.

In some variants of the exemplary embodiment, the one-sided flow-restricting unit 244, 246 has a flow-restricting element 262 that can be moved between a plurality of states, in particular at least one flow-restricting state and a flow-releasing state, with a flow in the restricted flow direction 252 being at least inhibited, preferably, in particular in the flow-restricting state is at least approximately completely prevented, and in the flow-releasing state, a flow in the preferred flow direction 254 is allowed to flow through the flow section 258 of the unit 244, 246 that restricts flow on one side at least substantially unhindered. For example, the one-sided flow-restricting unit 244, 246 comprises a rigid flow-restricting element 262, which is movably mounted with respect to its position between the at least one flow-restricting state and the at least one flow-releasing state, for example, is rotatably mounted about an axis of rotation 264, as exemplified in variants in FIGS 9 and 10.

In particular, the flow-restricting element 262 comprises a blocking section 266, for example made of a metallic material, in particular a sheet metal material, or made of a plastic, wherein the blocking section 266 in the flow-limiting state is arranged to at least partially, preferably at least approximately completely, close off a flow cross section of the flow section 258, for which purpose the blocking section 266 is in particular formed over a large area.

The position of the flow-restricting element 262 in the flow-restricting state is shown in dashed lines in FIGS. 9 and 10 by way of example.

A stop 268 is preferably formed in the flow section 258, for example from a line section wall, against which the flow-restricting element 262 rests in the flow-restricting state and is preferably pressed by the fluid flow directed in the blocked flow direction 252.

For example, the flow-restricting element 262 comprises an elastic body 272, for example made of elastomer, which is preferably arranged at least in sections on an edge of the flow-restricting element 262, in particular on an edge of the blocking section 262, for example at least on an end opposite a bearing of the flow-restricting element 262 of the flow-restricting element 262, in particular the blocking section 266, is arranged. Advantageously, the elastic body 272 is arranged at least substantially along the entire edge, with the exception of the bearing area.

For example, the elastic body 272 covers the edge and/or the end.

In particular, the elastic body 272 as a stop body rests against the stop 268 in the flow-limiting state and, due to its elasticity, when the one-sided flow-limiting unit 244, 246 closes, i.e. when the flow-limiting element 262 transitions into the flow-limiting state, when it hits the stop 268, it begins to cause shocks away.

The elastic body 272 advantageously acts as a sealing element, in particular by sealing against the stop 268, so that in the flow-limiting state, an even smaller quantity of fluid in the blocked flow direction 252 passes through the flow section 258 of the unit 244, 246 that restricts the flow on one side.

The flow-restricting element 262, in particular with its blocking section 266, preferably extends at least largely in the direction of the preferential passage direction 254 in the flow-releasing state, so that a flow cross-section in the passage section 258 is at least largely released and a fluid in the preferential passage direction 254 is at least essentially unhindered through the passage section 258 can flow through. In the flow-releasing state, the flow-restricting element 262 preferably rests, for example with its blocking section 266 and preferably with its elastic body 272, which in turn preferably serves as a stop body, on a stabilizer surface 274 that runs obliquely to the preferred passage direction 254, with the stabilizer surface 274 in particular at least below at an angle of at least 3° to the preferred passage direction 254.

In particular, the stabilizer surface 274 is aligned such that the flow-restricting element 262 lying against the stabilizer surface 274, in particular its blocking section 266, is still flowed against by the fluid flowing in the preferential passage direction 254 and is pressed against the stabilizer surface 274, thereby advantageously preventing the flow-restricting element from fluttering 262 is at least reduced or even at least substantially suppressed in the flow-releasing state, with the flutter being suppressed by the lower static pressure of the flowing fluid on one side of the flow-restricting element 262 compared to a higher static pressure of a substantially still fluid on the other side of the flow-restricting Element 262 could possibly arise because the flow-restricting element 262 could be pulled out of the flow-releasing state due to the lower static pressure and at the same time could be pushed back again by the flow.

For example, in favorable variants, the stabilizer surface 274 is formed by an inclined section in the line wall, as shown by way of example in FIG. 9 .

In other favorable variants, the stabilizer surface 274 is formed by a contact part which, for example, extends obliquely to the line wall, the contact part being a perforated plate, for example. For example, flow section 258 is designed, particularly in these variants, as a pipe section, in particular as a plastic pipe section, with at least stop 268 and, for example, the stabilizer surface advantageously being integrated in the pipe section, with flow section 258 preferably being designed as a cast part, for example in a shell model construction .

In a further variant of a one-sided flow-restricting unit 244, 246, which is shown by way of example in Fig. 11, the flow-restricting element 262, in particular at least one blocking section 266 thereof, is flexible and can be moved by changing its shape between at least one flow-restricting state and at least one flow-releasing state state trained.

In particular, the blocking section 266 is attached to one side, for example to a line section wall, of the flow section 258 .

In the at least one flow-limiting state, blocking section 266 protrudes into a flow cross-section of flow-through section 258, so that the flow-through section is at least partially, preferably at least approximately completely, closed by blocking section 266, which is particularly flexible.

By way of example, a shape and a position of the blocking section 266 in the at least one flow-limiting state are shown in broken lines in FIG. 11 .

In particular, a stop 268 protrudes into an interior space of the flow section 258, against which the flow-restricting element 262 bears, in particular with its blocking section 266 in the flow-restricting state, specifically in relation to the inhibited state Flow direction 252 in front of the stop 268 is applied, so that a fluid flowing in the blocked flow direction 252 presses the flow-restricting element 262 against the stop 268 and thus puts the flow-restricting element 262 into the flow-restricting state.

For example, stop 268 is formed from individual struts protruding into the interior of flow section 258 or is formed as a flat stop section having throughflow openings, for example as wire mesh and/or knitted fabric and/or wire filter, so that a fluid can reach stop 268 as long as blocking section 266 not applied to this, can flow past.

For example, the stop 268 is made of plastic, for example as an injection molded part, or made of a metallic material, for example a wire.

In particular, a stabilizer surface 274 is provided in flow section 258, which is preferably arranged in an outer region of a flow cross section, for example in the vicinity of a wall section of flow section 258, and runs obliquely to preferred flow direction 254, for example at least at an angle of at least 3°, and wherein the flow-restricting element 262, in particular with its blocking section 266, rests against the stabilizer surface 274 in the flow-releasing state and thus releases at least a large part of the flow cross-section of the flow-through section 258 and thus a fluid flowing in the preferred flow direction 254 at least essentially unhindered through the flow-through section 258 of the one-sided flow-blocking Unit 244, 246 can flow through. In turn, the fluid flowing in the preferential passage direction 254 advantageously presses the flow-restricting element 262 against the sloping stabilizer surface 274, with the slanted course of the stabilizer surface 274 also providing the flow-restricting element 262 with a contact surface for the fluid flowing in the preferential passage direction 264, and thus against the stabilizer surface 274 is pressed and preferably a fluttering is at least reduced or even at least essentially prevented. In this case, a reason for the fluttering and a reduction thereof is at least essentially the same as explained above in connection with the other alternative of the unit 244, 246 restricting flow on one side.

In some favorable variants of the exemplary embodiment, housing 118 is part of a housing device, designated as a whole by 280, which has a media module 282 attached in particular to housing 118 and/or integrated into housing 118, media module 282 at least partially containing line system 112, in particular Line sections and/or components thereof, as illustrated in FIG. 12 by way of example.

In particular, at least line sections of line device 114 for the fuel medium and components of this line device 114 are formed in media module 282 .

In particular, branching point 212 and junction point 218 of recirculation line 188 are formed in media module 282, and a supply line section 284 of supply line 162 leads in media module 282 from junction point 218 to anode fluid inlet 163 of the at least one fuel cell unit 110. Line section 214 connected in parallel, which merges with a section of the supply line, is preferably formed completely in media module 282, from branch point 212 to point of convergence 218, and fluid delivery unit 224 arranged therein and unit 244 that restricts flow on one side are advantageously also in the media module 282 trained.

Media module 282 advantageously includes a fuel medium inlet connection 286, from which a supply line section 288 in media module 282 leads to line section 214 connected in parallel and opens into it, in particular in the area of fluid delivery unit 224.

It is provided for the fuel medium inlet connection 286 that the reservoir 174 can be connected to it with a line section of the supply line 172 that is external to the media module 282 and is connected in a connected operating state.

For example, the control valve 228 is arranged in the feed line section 288 and is thus integrated in the media module 282 .

In particular, the media module has a recirculation outlet connection 292, which is connected to the branch point 212 by means of an outlet connection line section 293 of the line section 216 connected in parallel, which does not merge with the feed line 172.

In addition, the media module advantageously has a recirculation inlet connection 294, which is connected to an inlet connection line section 295 of the line section 216 connected in parallel, which does not merge with the supply line 172, in the media module 282 with the merging point 218. Thus, line section 216 connected in parallel, which does not merge with supply line 172, is at least partially formed in media module 282, and in particular it is provided that the preferably active fluid delivery unit 236 can be connected to recirculation outlet connection 292 and recirculation inlet connection 294 and is in a connected operating state connected.

The unit 246 that restricts flow on one side of the parallel-connected line section 216 that does not meet with the supply line 172 is preferably integrated in the media module 282 and is arranged, for example, in the outlet connection line section 293 and/or in the inlet connection line section 295 and/or at the junction point 218.

In particular, the discharge control unit 184 is also integrated in the media module 282 and is connected to the anode residual fluid outlet 178 by a line section running in the media module 282 .

In addition, a line section of the connecting line 182 leading away from the discharge line 176, in particular from the outlet control unit 184 and leading to the branching point 212, is preferably formed in the media module 282.

In particular, the media module 282 has an anode exhaust gas connection 296, which is connected to a drain line section 298 of the drain line 186 in the media module 282 directly or indirectly to the anode residual fluid outlet 178, with the drain line section 298 in the media module 282 in particular leading to the drain control unit 184 and via this with it the anode residual fluid outlet 178 is connected.

The anode residual fluid mixture can be discharged via the anode exhaust gas connection 296 . In particular, the media module 282 comprises at least line sections and/or some components of the line device 116 for the oxidation medium.

For example, the media module includes at least one oxidizing medium inlet connection, which is connected to a supply line section of the supply line with the cathode side 144 of the fuel cell unit 110 and to which, in particular, the fluid delivery unit 148 of the supply unit 146 can be connected with its high pressure side and is connected in a connected operating state.

In particular, the media module 282 includes a cathode residue fluid mixture outlet port, which is connected to a drain line section in the media module 282 of the drain line 156 with the cathode side 144 of the fuel cell unit 110 and via which the cathode residue fluid mixture can be drained.

For example, in some variants of the exemplary embodiment, the media module 282 at least partially includes the bypass line 157.

In variants of the exemplary embodiment, in which both of the two parallel line sections 214', 216' each have a supply line 1721 and 172II, the media module 282 is preferably also configured at least essentially as explained above.

In particular, respective feed line sections 288 lead from the fuel medium inlet connection 286 to the line sections 214′, 216′ connected in parallel. For example, in variants in which a passive fluid delivery unit 224, 236' is arranged in each of the two line sections 214', 216' connected in parallel, both line sections 214', 216' connected in parallel and preferably also both passive fluid delivery units 224 and 236' are in the media module 282 is formed.

In variants in which an active fluid delivery unit 236' is arranged in one of the two line sections connected in parallel, which unite with a supply line 172, the media module 282 preferably has a recirculation outlet connection 292 and a recirculation inlet connection 294 for this line section 216' connected in parallel as correspondingly explained above and for connecting the active fluid delivery unit 236'.

In particular, in such variants, the media module is otherwise configured as explained above.

In particular, a structure, a mode of operation and a method as well as advantages of the exemplary embodiment and the invention are briefly summarized as follows.

The fuel medium and the oxidizing medium are supplied to the at least one fuel cell unit 110 by means of the line devices 114, 116 for the fuel medium and for the oxidizing medium, which are at least partially chemically converted in the fuel cell unit 110 to form a product medium, and the fuel cell unit 110 makes electrical energy available in the process. The residual anode fluid mixture, which leaves the fuel cell unit 110 via the residual anode fluid outlet 178, typically still contains large, usable amounts of fuel medium fractions, which can be fed back to the anode fluid inlet 163 of the fuel cell unit 110 via the recirculation line 188, with fresh fuel medium fractions preferably being additionally supplied via the feed line 172 be added from the reservoir 174.

The fluid in the recirculation line 188 is conveyed by at least one of the fluid conveying units 224, 236 in the line sections 214, 216 connected in parallel in the direction of the junction point 218 and further to the anode fluid inlet 163.

This flow of fluid, which flows in the direction of the junction point 218, is allowed to pass at least essentially unhindered through the one unit 244, 246 with flow restriction on one side or the plurality of units 244, 246 with flow restriction on one side, since this flow direction corresponds to a preferred flow direction 254.

However, the one unit 244, 246 which restricts flow on one side or the plurality of units 244, 246 which restrict flow on one side at least or at least approximately prevent a fluid flow in the respective line section of the two line sections 214, 216 connected in parallel, a flow from the junction point 218 to the branch point 212.

In particular, this means that the fluid conveyed in the recirculation line 188 reaches the fuel cell unit 110 via the anode fluid inlet 163 and not from one of the fluid conveying units 224, 236 in one of those connected in parallel Line sections 214, 216 is funded and flows via the other of the two parallel line sections 216, 214 from the junction point 218 back to the branching point 212, bypassing the fuel cell unit 110.

Due to the design of recirculation line 188 with the two line sections 214 and 216 connected in parallel and in particular the fluid delivery units 224 and 236 provided therein, the fuel cell device 100 with its components can be operated as a function of the power P to be supplied, in particular as a function of that of the at least one fuel cell unit 110 electrical energy to be supplied, and the amounts of fuel medium and oxidizing medium required for this purpose are operated in different operating states. The different operating states differ, among other things, from the operating points of the two fluid delivery units 224 and 236, i.e. in particular by the fluid mass flows M delivered by these fluid delivery units 224, 236.

It is advantageous here for a unit 244, 246 that restricts flow on one side to be arranged in at least one, preferably in both, of the line sections 214 and 216 connected in parallel, so that when only one fluid delivery unit 224, 236 is delivering a fluid and/or one of the two fluid delivery units 224 , 236, for example, conveys considerably more fluid and exerts greater pressure, the fluid conveyed also flows in the direction of the anode fluid inlet 163 to the at least one fuel cell unit 110 and does not bypass the at least one fuel cell unit 110 through the other of the two line sections 214, 216 connected in parallel from the merge point flows back to branch point 212. In some favorable variants of the exemplary embodiment explained above, the fuel cell device 100 and in particular the fluid delivery units 224, 236 are designed for the operating states explained below, which are shown by way of example in FIG. 13, and in these operating states the fuel cell device 100 can be started up in a method for operating the same become.

In a low-load operation NL, in which the fuel cell device 100 only has to provide a low power P, only a small amount of fuel medium is required.

Due to the low requirement for fuel medium in the low-load operation NL, essentially no fluid is conveyed in the recirculation line 188 by the passive fluid delivery unit 224 in the line section 214 connected in parallel and which meets with the feed line 172, since the at most small amount of fuel medium fed via the feed line 172 as the driving medium does not apply sufficient pressure to suck in fluid from the connecting line 182 as the suction medium.

Therefore, in the low-load operation NL, the active fluid delivery unit 236 is operated in the line section 216 connected in parallel that does not meet with the supply line 172, which at least essentially applies the low total mass flow Mtot required in the low-load operation NL in the recirculation line 188.

In the figs. 13 to 18, the mass flow M236 delivered by the fluid delivery unit 236, 236' is shown in dashed lines, the mass flow M224 delivered by the fluid delivery unit 224 is shown in dots, and the fluid mass flow Mtot=M236+M224 delivered jointly by both fluid delivery units 224, 236 is shown by a solid line. If the fluid quantity M236 or M234 conveyed by the fluid conveying unit 236, 236′ or 224 corresponds to the total fluid quantity Mtot conveyed, the dashed line or dotted line is shown slightly offset to the solid line for a clearer representation.

In a medium-load operation ML, the amount of fresh fuel medium to be applied for the medium power P, which is supplied via the supply line 172, is sufficient to suck in the entire mass flow Mtot in the recirculation line 188 as a suction medium in the passive fluid delivery unit 224 as a driving medium, so that in medium-load operation ML only a mass flow is promoted via the passive fluid delivery unit 224 and the active fluid delivery unit 236 is switched off, so that no additional energy is required for this and the efficiency of the fuel cell device 100 is increased.

In particular, the quantity of fluid M224 delivered by the passive fluid delivery unit 224 increases in a transition range between low-load operation NL and medium-load operation ML, and accordingly the active fluid delivery unit 236 is successively switched off in the transition range.

In particular, in low-load operation NL and in medium-load operation ML, a fluid is only supplied by one fluid delivery unit, namely fluid delivery unit 236 in low-load operation NL and fluid delivery unit 224 in medium-load operation ML, through the respective line section and through unit 244 that restricts flow on one side , 246 in the other of the two line sections 214, 216 connected in parallel, short-circuiting of the respective fluid delivery unit 224, 236 is avoided. In this variant, a total fluid mass flow Mtot to be delivered in high-load operation HL in recirculation line 188 is greater than a maximum amount of fluid that can be delivered by passive fluid delivery unit 224, so that in high-load operation HL active fluid delivery unit 236 is added in the other of the two line sections 216 connected in parallel is to promote the total required amount of fluid Mtot by both fluid delivery units 236 and 224 together through the recirculation line 188.

In particular, it is provided that in high-load operation HL the active fluid-conveying unit 236 is switched on successively, i.e. in particular in a transition region from medium-load operation ML to high-load operation HL, the active fluid-conveying unit 236 is switched on and in high-load operation HL it is operated more strongly as the required power P increases , so that the amount of fluid M236 conveyed by this fluid conveying unit 236 increases.

For example, one advantage of this variant with such a design of the fuel cell device 100 and in particular of the fluid delivery units 224 and 236 is that smaller fluid delivery units 224, 236 can be used and a large amount of fluid can still be used in high-load operation HL by operating the two fluid delivery units 224, 236 Mtot is eligible for the large services required. For example, the smaller fluid delivery units 224, 236 save weight and, for example, they are more economical.

In an alternative mode of operation of the fuel cell device 100 and, for example, an alternative design of the same, which is shown by way of example in FIG. 14, it is provided that the active fluid delivery unit 236 is also operated in a medium-load operation ML. For example, it is provided that, as in the alternative explained above, only the active fluid delivery unit 236 delivers the fluid mass flow Mtot in the recirculation line 188 in the low-load operation NL.

However, in this variant it is provided that the active fluid delivery unit 236 also delivers a fluid flow M236 in medium-load operation ML and high-load operation HL, for example an at least approximately constant fluid flow in medium-load operation ML and high-load operation HL. The increasing amount of fluid required to be delivered with increasing power P in medium-load operation ML and in high-load operation HL is delivered through passive fluid delivery unit 224, in particular since as power P increases, a larger amount of fresh fuel medium is supplied via supply line 172 and this is used as the propellant medium sucks in an increasingly larger quantity of fluid from the recirculation line 188 as suction medium.

For example, one advantage of this variant is that since both fluid delivery units 236, 224 are operated in medium-load operation ML, larger delivered total fluid quantities Mtot can be achieved more quickly.

In a further variant of a design and mode of operation of fuel cell device 100, the operating states of which are shown by way of example in Fig. 15, passive fluid delivery unit 236 in line section 214 that joins supply line 172 is designed in such a way that it can also be used in high-load operation HL and at the maximum the power P to be provided by the fuel cell device 100 can deliver the maximum amount of fluid M to be delivered required for this. In this variant, it is therefore provided that in high-load operation HL only the passive fluid delivery unit 224 delivers fluid in the recirculation line 188 and thus, for example, the fuel cell device 100 also has a high degree of efficiency in high-load operation HL, since there is no additional active fluid delivery unit 236 in high-load operation HL must be switched on, which would require additional energy.

In this variant, too, it is provided that in the low-load operation NL, in which the passive fluid delivery unit 224, in particular due to the small quantity of fresh fuel medium supplied through the supply line 172, which as a propellant medium does not have a sufficient suction effect for sucking in fluid in the recirculation line 188 can, does not deliver any significant amount of fluid M224, the active fluid delivery unit 236 is operated, and the amount of fluid M236 delivered by this delivers essentially the entire total amount of fluid Mtot to be delivered in the recirculation line 188.

In a further variant of a fuel cell device 100, in particular for variants in which both of the two line sections 214', 216' connected in parallel combine with a respective supply line 1721, 172II, as shown by way of example in FIGS. 5 and 6, a configuration and operation thereof with operational states exemplified in FIG. 16 and a method for operating the fuel cell device 100 are as follows.

The passive fluid delivery unit 224, which is designed in particular for small fluid volume flows, is designed in such a way that the only small amount of fresh fuel medium that is supplied via the corresponding supply line 1721 in low-load operation NL is sufficient to suck in fluid from the connecting line 182 as a suction medium and to promote through the recirculation line 188. In particular, efficient low-load operation is achieved in this variant, since no active fluid delivery unit is required for this. For example, there is in principle a particularly extremely small power range for lower powers than in low-load operation, in which the fluid delivery unit 224, which is designed particularly small, could not deliver any fluid in the recirculation line 188 due to the insufficient pressure, but this low power range is so small and/or or the performance in this area is so small that this area is not approached, since the fuel cell device should always generate at least the performance provided in low-load operation, so that this area is irrelevant.

Since this particularly small fluid delivery unit 224 is designed in particular for low-load operation, it reaches saturation with larger fluid volume flows and cannot alone deliver the fluid volume flows required at least for high-load operation HL and, for example, also for medium-load operation ML.

Therefore, at least in high-load operation and, for example, also in medium-load operation, the additional active or passive fluid delivery unit 236' is switched on in the other of the two parallel-connected line sections 216', 214', so that the amounts of fluid M236' delivered by it and the fluid delivered by the particularly small fluid delivery unit 224 In particular, the required total fluid quantity Mtot is reached when the delivered quantity of fluid M224 is saturated.

Since in this variant neither of the two fluid delivery units 236′, 224 alone have to apply the entire required total quantity of fluid Mtot in high-load operation HL, they can be designed and made smaller, for example, which allows weight and/or installation space savings. In particular, this variant is at least similar to the variant shown as an example in Fig. 14 in that in low-load operation only one fluid delivery unit applies the total fluid quantity Mtot and at least in high-load operation HL and, for example, also in medium-load operation ML, the two fluid delivery units in both of the two connected in parallel Line sections for applying the total amount of fluid Mtot promote fluid, and to the extent that these two variants are similar, reference is made to the other in each case for the description of the same.

In further examples in Figs. 17 and 18, the passive fluid delivery unit 224, which is particularly small, is designed to deliver the required amount of fluid Mtot in low-load operation NL, in particular as explained above in connection with the variant shown as an example in FIG insofar as reference is made.

However, in the variant shown by way of example in Fig. 17, it is provided that the further fluid delivery unit 236' in the other of the two line sections 216', 214' is designed in such a way that the total amount of fluid Mtot required in medium-load operation ML is applied alone, so that in medium-load operation ML the fluid in the recirculation line 188 and the fluid comprising fresh fuel medium components is only conveyed via the further, in particular active or passive, fluid conveying unit 236′.

In particular, the maximum amount of fluid that can be delivered by the additional fluid delivery unit 236' is not sufficient for high-load operation HL, so that the particularly small fluid delivery unit 224 is also switched on in this case in order to deliver the entire fluid quantity Mtot required for high-load operation HL. In particular, this variant is, at least to the extent that in low-load operation NL only one fluid delivery unit and in medium-load operation only the other fluid delivery unit essentially delivers fluid and that at least in high-load operation HL both fluid delivery units deliver fluid, with the example in connection with Fig. 13 Explained variant similar, so that, at least insofar as the two variants correspond to each other, mutual reference is made to the statements on the two variants.

In a further variant shown by way of example in FIG. 18 , it is again provided that the passive fluid delivery unit 224 , which is designed in particular to be small, delivers the required quantity of fluid Mtot alone in the low-load operation NL.

However, in this variant, it is provided that the further fluid delivery unit 236' is designed such that it can deliver the total fluid quantity Mtot required at least for medium-load operation ML and/or at least for high-load operation HL alone and thus only in the corresponding medium-load operation and/or high-load operation fluid is conveyed by the further fluid conveying unit 236'.

In particular, this variant is similar to the variant explained by way of example in connection with FIG. 15 , so that insofar as these two variants correspond to one another, reference is made in full to the explanations in connection with the respective other variant.

REFERENCE LIST

fuel cell device

fuel cell unit

piping system

Fuel medium conduit device

Conducting device for oxidizing medium

inner space

Housing

temperature control device

Line device for temperature control medium

supply line

discharge line

Line device for housing ventilation

ventilation line

vent line

supply line

cathode side

supply unit

compressor

suction line

filter

drain line

bypass line

directional valve

supply line

anode fluid inlet

anode side

supply unit

compressor

supply line

reservoir discharge line

Anode residual fluid outlet connection line drain control unit

drain line

recirculation line

Branching point Line section connected in parallel Line section connected in parallel Confluence point Fluid delivery unit

intake tract

control valve

Fluid delivery unit flow-restricting unit on one side flow-restricting unit on one side restricted flow direction preferred passage direction flow section flow-restricting element axis of rotation

lockdown section

Stop elastic body stabilizer surface

Housing device media module

Supply Line Section Fuel Medium Inlet Connection

Feed line section recirculation outlet connection

Outlet port line section recirculation inlet port Inlet connection line section Anode exhaust connection Drain line section

Claims

77

P A T E N T C H A N G R U C H E Fuel cell device (100) comprising at least one fuel cell unit (110) and a line system (112) comprising at least one line device (114) for a fuel medium, wherein the line device (114) for the fuel medium comprises a recirculation line (188) leading from an anode residual fluid outlet (178) which comprises at least one fuel cell unit (110) leading to an anode fluid inlet (163) which leads to at least one fuel cell unit (110) and the recirculation line (188) is designed to branch at a branch point (212) into two line sections (214, 216) connected in parallel and the two line sections connected in parallel

(214.216) come together again at a merging point (218) of the recirculation line (188), the merging point (218) being arranged closer to the anode fluid inlet (163) than the branching point (212) with respect to a fluid path in the recirculation line (188) and wherein in at least one of the two line sections connected in parallel

(214.216), preferably in both of the two line sections (214, 216) connected in parallel, at least one unit (244, 246) that restricts flow on one side is arranged, which a fluid flow flowing from the junction point (218) in the direction of the branching point (212) in this line section ( 214, 216) is designed to be at least inhibitory. Fuel cell device (100) according to Claim 1, characterized in that a fluid delivery unit (224, 236) is arranged in at least one of the two line sections (214, 216) connected in parallel and in particular in at least the other of the two line sections (214, 216) connected in parallel at least one unit (244, 246) restricting flow on one side is arranged. 78 Fuel cell device (100) according to one of the preceding claims, characterized in that the line device (114) for the fuel medium comprises at least one feed line (172) for the supply of fresh fuel medium, for example from a reservoir (174), and in which in particular the at least one supply line (172) combined with one of the two line sections connected in parallel. Fuel cell device (100) according to one of the preceding claims, characterized in that in the line section (214) of the two line sections (214, 216) connected in parallel, which merges with the at least one supply line (172), an in particular passive fluid delivery unit (224, 236' ) is arranged. Fuel cell device (100) according to one of the preceding claims, characterized in that both of the two line sections (214, 216) connected in parallel combine with one supply line each (1721, 172II) and that in particular in one of the two line sections (214, 216) a in particular passive fluid delivery unit (224, 236') and in the other of the two line sections (216, 214) one, in particular passive or active fluid delivery unit (224, 236') is arranged. Fuel cell device (100) according to one of the preceding claims, characterized in that an in particular passive fluid delivery unit (224, 236 ') in a line section (214) of the two line sections connected in parallel (214, 216), which combines with a supply line (172), a Intake tract (226), in which in particular a fluid flowing from one of the merging line sections sucks in fluid as a driving medium from the other of the merging line sections as suction medium. 79 Fuel cell device (100) according to one of the preceding claims, characterized in that in a line section (216) of the two line sections (214, 216) connected in parallel, which does not merge with a supply line (172), an in particular actively driven fluid delivery unit (236) is arranged is. Fuel cell device (100) according to one of the preceding claims, characterized in that at least one line section (216) of the two line sections (214, 216) connected in parallel, which does not meet with a supply line (172), contains at least one unit (244, 246 ) is arranged. Fuel cell device (100) according to one of the preceding claims, characterized in that at least in the line section (216) of the two line sections (214, 216) connected in parallel, which does not meet with a supply line (172), at least between the branching point (212) and the Fluid delivery unit (236) a one-sided flow-obstructing unit (244, 246) is arranged and/or at least between the fluid delivery unit (236) and the merging point (218) a one-sided flow-obstructing unit (244, 246) is arranged. Fuel cell device (100) according to one of the preceding claims, characterized in that at least one line section (214) of the two line sections (214, 216) connected in parallel, which unites with a supply line (172), has at least one unit (244, 246) which is flow-inhibiting on one side arranged . 80 Fuel cell device (100) according to one of the preceding claims, characterized in that at least in one line section (214) of the two line sections (214, 216) connected in parallel, which merges with a feed line (172) at a junction point, between the branching point (212) and at least one unit (244, 246) restricting flow on one side is arranged at the junction point. Fuel cell device (100) according to one of the preceding claims, characterized in that in at least one line section (214) of the two line sections (214, 216) connected in parallel, which merges with a supply line (172), between the branching point (212) and the in particular passive Fluid delivery unit (224) at least one one-sided flow-blocking unit (244.246) is arranged. Fuel cell device (100) according to one of the preceding claims, characterized in that in at least one unit (244, 246) which restricts flow on one side, a flow resistance in a restricted flow direction (252) for a fluid flowing through the unit (244, 246) is at least twice as great is, in particular, at least ten times greater than a flow resistance in a preferred passage direction (254) opposite to the blocked flow direction (252). Fuel cell device (100) according to one of the preceding claims, characterized in that in at least one unit (244, 246) which restricts flow on one side, a flow of fluid in the restricted flow direction (252) is at least approximately completely prevented. 81. The fuel cell device (100) according to any one of the preceding claims, characterized in that in at least one unit (244, 246) that restricts flow on one side, a flow section (258) is designed asymmetrically in such a way that there is a flow resistance in the flow section for a fluid flowing through the flow section (258). (258) in the blocked flow direction (252) is greater, in particular at least twice as large, in particular at least ten times as large, than a flow resistance in the blocked flow direction (252) opposite the preferred passage direction (254). Fuel cell device (100) according to one of the preceding claims, characterized in that at least one unit (244, 246) that restricts flow on one side has a plurality of states, in particular at least one flow-limiting state and at least one flow-releasing state, and in particular depending on at least one influencing factor, this at least one on one side flow-restricting unit (244,246) changes its state and/or assumes it. Fuel cell device (100) according to the preceding claim, characterized in that the unit (244, 246) which has several states which restrict flow on one side assumes the at least one flow-limiting state when a fluid flows in the blocked flow direction and when a fluid flows in the preferential flow direction (254). Fluid takes the at least one flow-enabling state. Fuel cell device (100) according to one of the preceding claims, characterized in that the at least one influencing factor for changing and/or assuming a state of the at least one one-sided flow-restricting unit (244, 246) having a plurality of states is a parameter of the fluid in 82 of the unit (244, 246) and/or the state of the fluid, in particular the flow of the fluid, in particular a flow direction of the fluid and/or a flow velocity of the fluid and/or a pressure of the fluid and/or a pressure gradient in the Fluid and / or a change in pressure of the fluid. Fuel cell device (100) according to one of the preceding claims, characterized in that a controller is provided with which the at least one one-sided flow-restricting unit (244, 246) having a plurality of states can be set to a desired state. Fuel cell device (100) according to one of the preceding claims, characterized in that at least one unit (244, 246) which restricts flow on one side has a movable flow-restriction element (262) and in particular a state of the unit (244, 246) which restricts flow on one side by an orientation and/or a position and/or defining a shape of the moveable flow restriction member (262). Fuel cell device (100) according to one of the preceding claims, characterized in that in at least one unit (244, 246) which restricts flow on one side its movable flow restriction element (262) is a rigid, movably mounted flow restriction element (262). Fuel cell device (100) according to one of the preceding claims, characterized in that in at least one unit (244, 246) which restricts flow on one side its movable flow restriction element (262) is an at least partially movable flow restriction element (262). 83 Fuel cell device (100) according to one of the preceding claims, characterized in that at least one one-sided flow-restricting unit (244,246) has two stops between which the movable flow-restriction element (262) can be positioned in different states and can move. Fuel cell device (100), in particular according to one of the preceding claims, characterized in that it comprises a housing device (280) having a housing (118) for at least one fuel cell unit (110) and a media module (282), with a line system (112) at least partially is formed in the media module (282) and in particular at least one unit (244, 246) that restricts flow on one side is arranged in the media module (282). Fuel cell device (100) according to one of the preceding claims, characterized in that the recirculation line (188), in particular the two line sections (214, 216) of the recirculation line (188) connected in parallel, is/are formed at least in sections in the media module (282). Fuel cell device (100) according to one of the preceding claims, characterized in that a line section (214) of the two line sections (214, 216) connected in parallel, which merges with a supply line (172), is partially or completely formed in the media module (282). Fuel cell device (100) according to one of the preceding claims, characterized in that the media module (282) has a fuel medium inlet connection (286) and in particular at least one feed line section (288) from the fuel medium inlet connection (286) to a Junction point with a line section (214) of the two line sections (214, 216) connected in parallel, which unites with a supply line (172), in which the media module (282) is formed. Fuel cell device (100) according to one of the preceding claims, characterized in that the media module (282) for a line section (216) of the two parallel line sections (214, 216) has a recirculation outlet connection

(292), to which in the media module (282) a line section

(293) from the branching point (212), and has a recirculation inlet connection (294), from which a line section (295) in the media module (293) leads to the merging point (218), and in particular a particularly active fluid delivery unit (236) for the line section of the two line sections (214, 216) connected in parallel can be connected between the recirculation outlet connection (292) and the recirculation inlet connection (294). Fuel cell device (100) according to one of the preceding claims, characterized in that an active fluid delivery unit (236) for low-load operation (NL) of the fuel cell device is provided and designed. Fuel cell device (100) according to one of the preceding claims, characterized in that a passive fluid delivery unit (224, 236') is provided and designed for low-load operation (NL) of the fuel cell device. Fuel cell device (100) according to one of the preceding claims, characterized in that a passive fluid delivery unit (224, 236') is provided and designed for medium-load operation (ML) and/or high-load operation (HL) of the fuel cell device (100). Fuel cell device (100) according to one of the preceding claims, characterized in that it is designed and constructed such that in high-load operation (HL) of the same only one of the fluid delivery units (224, 236) is to be operated. Fuel cell device (100) according to one of the preceding claims, characterized in that it is designed and constructed in such a way that both fluid delivery units (224, 236) are to be operated during high-load operation of the same. Vehicle which is at least partially driven by at least one fuel cell unit (110), characterized in that it has a fuel cell device (100) according to one of the preceding claims.