Vehicle having a fuel cell system and method for operating a fuel cell system

Abstract

The invention relates to a vehicle comprising a fuel cell system (10) having a fuel cell assembly (14) and a fuel cell exhaust system (20) which receives fuel cell exhaust gas (AB) exiting the fuel cell assembly, the fuel cell exhaust system has a fuel cell exhaust discharge region (34) for discharging fuel cell exhaust from the fuel cell exhaust system and an ambient air heating assembly (38) for heating ambient air (U) to be mixed with at least one part of the fuel cell exhaust, the ambient air heating assembly has an ambient air discharge area (42) for discharging ambient air (UE) heated in the ambient air heating assembly. The fuel cell exhaust discharge region (34) is positioned downstream of the ambient air discharge region with respect to an ambient air flow direction (US) of heated ambient air discharged from the ambient air heating assembly over the ambient air discharge region.

Description

Technical Field

[0001] The invention relates to a vehicle having a fuel cell system and a method for operating a fuel cell system in a vehicle. Background Art

[0002] In a fuel cell system for generating electrical energy in a vehicle, during the conversion of an anode gas containing hydrogen (H2) supplied to the anode region of a fuel cell assembly and a cathode gas containing oxygen (O2) supplied to the cathode region of the fuel cell assembly, an anode exhaust gas relatively heavily enriched with water or water vapor and / or a cathode exhaust gas relatively heavily enriched with water or water vapor is produced, depending on the type of fuel cell assembly used. If such a fuel cell exhaust gas containing or having anode exhaust gas and / or cathode exhaust gas heavily enriched with water or water vapor is discharged to the environment at relatively low ambient temperatures, a strong misting may occur due to condensation of water when the water-containing fuel cell exhaust gas comes into contact with relatively cold ambient air at the discharge point of the fuel cell exhaust gas. This is not only undesirable for visual reasons, but also poses the risk of ice forming due to water condensing in and depositing on the base at low ambient temperatures and in a particularly cold base.

[0003] From the German patent application DE102023108806, which was published later, a fuel cell exhaust device is known, in which the fuel cell exhaust gas containing water or water vapor is mixed with the ambient air heated on the ambient air heating component in a fuel cell exhaust gas / ambient air mixing component integrated into the fuel cell exhaust device. The fuel cell exhaust gas / ambient air mixing component includes a mixing volume formed in a mixing chamber, into which the heated ambient air and the fuel cell exhaust gas are introduced. After the fuel cell exhaust gas and the ambient air are mixed, the mixture of the fuel cell exhaust gas and the heated ambient air formed in the mixing volume is discharged from the mixing chamber to the environment via the part of the fuel cell exhaust device that is located downstream of the mixing chamber at the exhaust opening of the fuel cell exhaust device. In the area of ​​the exhaust opening of the fuel cell exhaust device, the mixture composed of the fuel cell exhaust gas and the heated ambient air is mixed with the unheated ambient air. Summary of the invention

[0004] The object of the present invention is to provide a vehicle having a fuel cell system and a method for operating a fuel cell system in a vehicle, with which the risk of atomization when the fuel cell exhaust gas is discharged into the environment can be effectively suppressed.

[0005] According to a first aspect of the invention, this object is achieved by a vehicle comprising:

[0006] a fuel cell system having a fuel cell assembly and a fuel cell exhaust device for receiving fuel cell exhaust from the fuel cell assembly, the fuel cell exhaust device having a fuel cell exhaust exhaust region for discharging fuel cell exhaust from the fuel cell exhaust device,

[0007] - an ambient air heating assembly for heating ambient air to be mixed with at least a portion of the fuel cell exhaust gas, the ambient air heating assembly having an ambient air exhaust area for discharging ambient air heated in the ambient air heating assembly.

[0008] In one embodiment of the vehicle according to the invention, the fuel cell exhaust gas discharge area is located downstream of the ambient air discharge area with respect to the ambient air flow direction of the heated ambient air emitted from the ambient air heating assembly at the ambient air discharge area. This means that the fuel cell exhaust gas discharge area can be circulated by the heated ambient air leaving the ambient air heating assembly and thus induce or assist in the mixing of the fuel cell exhaust gas and the heated ambient air.

[0009] In an alternative embodiment of the vehicle according to the invention, the fuel cell exhaust gas discharge area is located upstream of the ambient air discharge area with respect to the ambient air flow direction of the heated ambient air discharged from the ambient air heating assembly at the ambient air discharge area. In this embodiment, it can be provided that the fuel cell exhaust gas discharged at the fuel cell exhaust gas discharge area flows around the ambient air heating assembly, but is not heated in the ambient air heating assembly and is mixed with the heated ambient air discharged from the ambient air heating assembly.

[0010] In another alternative embodiment according to the invention, which can also be implemented in the previously explained alternative embodiment of the vehicle, the fuel cell exhaust gas discharge area and the ambient air discharge area are positioned such that the flow of the fuel cell exhaust gas discharged at the fuel cell exhaust gas discharge area and the flow of the heated ambient air discharged at the ambient air discharge area at least partially pass through each other. In this embodiment, the two air flows can be directed, for example, substantially parallel or at an angle to each other into substantially the same volume area, so that the air flows pass through each other and mix the fuel cell exhaust gas with the heated ambient air.

[0011] By mixing the heated ambient air with the fuel cell exhaust gas which is strongly enriched with water or water vapor in the vehicle constructed according to the invention, it is possible that before the fuel cell exhaust gas or the mixture generated by the fuel cell exhaust gas and the heated ambient air is discharged, the mixture is provided with a relative humidity significantly below 100%. If this mixture with a relative humidity significantly reduced compared to the fuel cell exhaust gas comes into contact with relatively cold ambient air when discharged from the fuel cell exhaust gas device, the risk that the relative humidity reaches or exceeds a value of 100% and thus atomization occurs due to spontaneous cooling of the mixture is significantly reduced. Since the heated ambient air is mixed with the fuel cell exhaust gas discharged from the fuel cell exhaust gas device in the vehicle constructed according to the invention, it is not necessary to integrate a system area into the fuel cell exhaust gas device, which system area is used to mix the fuel cell exhaust gas and the heated ambient air. As a result, the fuel cell exhaust gas device can be conventionally constructed, with only its fuel cell exhaust gas discharge area being positioned on or in the vehicle so that the fuel cell exhaust gas discharged from the fuel cell exhaust gas device and the heated ambient air are discharged into the same volume area, for example in the vehicle or in an area outside the vehicle.

[0012] In order to be able to effectively heat the ambient air to be mixed with the fuel cell exhaust gas in a heated manner without additional energy input or without using electrical energy generated in the fuel cell system, it is proposed that the ambient air heating component has at least one heat exchanger through which the ambient air to be heated and a cooling medium flowing in a cooling circuit can flow, and the heat exchanger is used to transfer the heat contained in the cooling medium to the ambient air to be heated.

[0013] If a plurality of cooling circuits are provided in the vehicle, for example in order to be able to cool different system areas of the vehicle, for example the electronics on the one hand or the fuel cell assembly on the other hand, independently of one another and to be able to maintain these system areas independently of one another at different temperature levels, the ambient air heating assembly can include a plurality of heat exchangers through which the ambient air to be heated can flow in series. In this case, for efficient heating of the ambient air, for example, the fuel cell exhaust gas discharge area can be positioned downstream of the heat exchanger of the plurality of heat exchangers which is positioned furthest downstream with respect to the flow direction of the ambient air to be heated.

[0014] In order to achieve an adjustment of the temperature of the heated ambient air, in particular also adapted to the water content of the fuel cell exhaust gas, the ambient air heating assembly can be equipped with a throttle assembly for throttling the amount of ambient air to be heated that flows through the ambient air heating assembly.

[0015] In order to discharge the fuel cell exhaust gas into a volume region outside the fuel cell exhaust gas device, the fuel cell exhaust gas outlet region may have at least one fuel cell exhaust gas outlet opening.

[0016] In this case, effective mixing of the fuel cell exhaust gas and the heated ambient air can be assisted, for example, by:

[0017] at least one, preferably each, fuel cell exhaust gas discharge opening is configured to discharge fuel cell exhaust gas in a fuel cell exhaust gas flow direction substantially corresponding to said ambient air flow direction,

[0018] or / and

[0019] at least one, preferably each, fuel cell exhaust gas discharge opening is configured to discharge fuel cell exhaust gas in a fuel cell exhaust gas flow direction substantially opposite to the direction of flow of said ambient air,

[0020] or / and

[0021] At least one, preferably each, fuel cell exhaust gas outlet opening is designed to emit a fuel cell exhaust gas flow that expands in a fan-shaped or cone-shaped manner.

[0022] At this point it is pointed out that the ambient air flow direction or the fuel cell exhaust gas flow direction refers to the flow direction or main flow direction which the ambient air or the fuel cell exhaust gas has predominantly or on average at the respective point of emission.

[0023] In order to further assist in the mixing of heated ambient air and fuel cell exhaust gas, a mixing arrangement having at least one ambient air / fuel cell exhaust gas mixer may be provided downstream of the fuel cell exhaust gas discharge region with respect to the ambient air flow direction.

[0024] In order to be able to mix the heated ambient air and the fuel cell exhaust gas, which leads to a reduction in relative humidity, before the heated ambient air and the fuel cell exhaust gas are discharged into the environment, i.e., the unheated ambient air, it is proposed that the ambient air discharge area is arranged to discharge the heated ambient air into an equipment space of the vehicle that is open to the environment via at least one opening area, and the fuel cell exhaust gas discharge area is arranged to discharge the fuel cell exhaust gas into the equipment space. Such an equipment space can be a space or a volume area in the vehicle, in which other system areas, such as a drive motor, an ambient air heating component, components of the vehicle electronics, and the like, are also arranged.

[0025] In order to ensure essentially uniform mixing of the fuel cell exhaust and the heated ambient air in the equipment space before discharge into the environment, it is advantageous if the distance between the fuel cell exhaust discharge area and the ambient air discharge area is less than 50%, preferably less than 10%, of the distance between the at least one opening area and the ambient air discharge area.

[0026] In order to achieve sufficient flow through the ambient air heating assembly with ambient air to be heated, for example when the vehicle is stationary or only moving slowly or when the ambient air heating assembly is located in an area of ​​the vehicle that does not flow directly into the vehicle even when the vehicle is moving, it is proposed in an independent inventive aspect, which can of course be combined with the inventive aspects explained above or below, that the ambient air heating assembly is equipped with an ambient air fan for conveying ambient air to be heated and / or heated ambient air. If the ambient air fan is arranged downstream of the ambient air heating assembly with respect to the flow direction of the ambient air, for example upstream of the exhaust gas discharge area of ​​the fuel cell, the ambient air fan simultaneously generates eddies for the heated ambient air, which contribute to better mixing with the exhaust gas of the fuel cell.

[0027] If the ambient air blower is arranged downstream of the fuel cell exhaust gas discharge region with respect to the ambient air flow direction, particularly effective mixing of heated ambient air and fuel cell exhaust gas can be achieved by utilizing the conveying effect of the ambient air blower.

[0028] The fuel cell exhaust device may include a fuel cell exhaust treatment component, and the fuel cell exhaust treatment component includes at least one of the following structural components:

[0029] -Liquid separator,

[0030] - Catalyst,

[0031] -Muffler.

[0032] The present invention also relates to a method for operating a fuel cell system in a vehicle, wherein the vehicle is preferably a vehicle constructed according to the present invention, in which a mixture of ambient air and fuel cell exhaust gas emitted at a fuel cell exhaust exhaust area of ​​a fuel cell exhaust device of a fuel cell component assigned to the fuel cell system is generated, and at least a portion of the ambient air mixed with the fuel cell exhaust is heated before mixing with the fuel cell exhaust gas.

[0033] The heated ambient air and the fuel cell exhaust gas can be discharged into an equipment space of the vehicle that is open to the environment in order to achieve uniform mixing, so that a mixture of fuel cell exhaust gas and heated ambient air is essentially formed in the equipment space before contact with the unheated ambient air surrounding the vehicle.

[0034] The ambient air to be mixed with the fuel cell exhaust gas in a heated manner can be heated in at least one heat exchanger by thermal interaction with a cooling medium flowing in a cooling circuit of the vehicle.

[0035] In order to set the temperature of the ambient air to be heated in the at least one heat exchanger, the mass flow of the ambient air flowing through the at least one heat exchanger and / or the mass flow of the cooling medium flowing through the at least one heat exchanger can be varied. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention is described in detail below with reference to the accompanying drawings.

[0037] Figure 1 A schematic diagram showing a vehicle having a fuel cell system;

[0038] Figure 2 An alternative design of an ambient air heating assembly is shown;

[0039] Figure 3 An alternative design of a vehicle is shown. DETAILED DESCRIPTION

[0040] Figure 1 A fuel cell system is shown generally at 10, which can be used in a vehicle 12 for providing electrical energy. The fuel cell system 10 includes a fuel cell assembly 14, which can be constructed, for example, as one or more fuel cell stacks and which in principle includes an anode gas G containing hydrogen. A The anode region 16 is supplied with a cathode gas G containing oxygen. K The cathode region 18 is supplied. In the fuel cell process, the anode gas G is converted A and cathode gas G K In the case of anode exhaust gas A, which usually contains residual hydrogen, electrical energy is generated on the one hand and an anode exhaust gas A which usually contains residual hydrogen is generated on the other hand. A and the cathode exhaust A which usually contains residual oxygen K Depending on the fuel cell type, the anode exhaust gas A A or cathode exhaust A K It contains predominantly a relatively high proportion of water or water vapor, which has a relative humidity in the range of at most 90 to 100%.

[0041] The fuel cell assembly 14 is provided with a fuel cell exhaust device generally indicated at 20. In the example shown, the fuel cell exhaust device 20 receives the anode exhaust gas A A and cathode exhaust A K As fuel cell exhaust gas A B Alternatively, the fuel cell exhaust gas system 20 can be designed in such a way that it receives only the exhaust gas flow of the two exhaust gas flows leaving the fuel cell assembly 14 that is highly or relatively highly enriched with water or water vapor.

[0042] A fuel cell exhaust treatment component 22 may be provided in the upstream region of the fuel cell exhaust device 20. The fuel cell exhaust treatment component 22 may include, for example, a liquid separator 24 in which the fuel cell exhaust gas A may be separated. B The fuel cell exhaust gas treatment component 22 can be used to treat the fuel cell exhaust gas A. B Aftertreatment is performed including a catalytic converter 26 and may include a muffler 28 , for example.

[0043] It is noted that further or additional components of the fuel cell exhaust gas treatment assembly 22 may be provided or that individual components of the three components shown of the fuel cell exhaust gas treatment assembly 22 may not be present in the fuel cell exhaust gas device 20 or may be positioned in another order.

[0044] The fuel cell exhaust device 20 also includes a fuel cell exhaust gas discharge area 34 downstream of the fuel cell exhaust treatment component 22. In the fuel cell exhaust gas discharge area 34, the fuel cell exhaust device 20 has at least one, and in the illustrated design example, a plurality of fuel cell exhaust gas discharge openings 32, through which the fuel cell exhaust gas A B Leaving the fuel cell exhaust device 20. The fuel cell exhaust gas outlet region 34 may, for example, include a tubular end section 30 of the fuel cell exhaust device 20, in which a plurality of the fuel cell exhaust gas outlet openings 32 are arranged in a longitudinal direction of the end section, i.e. also in the flow direction, one after the other or / and distributed around the periphery of the end section.

[0045] exist Figure 1 In the design example shown in FIG. 1 , the fuel cell exhaust gas discharge area 34 is positioned so that the fuel cell exhaust gas A BReleased into the volume of a complete set of equipment space 36 in the vehicle 12, for example. Other system areas of the vehicle 12, such as the electric drive motor of the vehicle 12 powered by the fuel cell assembly 14 or the battery, components of the vehicle electronics, or the ambient air heating assembly 38 explained below, can be arranged in the complete set of equipment space 36. The complete set of equipment space 36 is not a volume enclosed in the vehicle 12 in principle, but is usually open to the outside, that is, to the environment, via a plurality of opening areas 40. Access to the complete set of equipment space 36 can be obtained via a movable closing flap, such as a motor cover or the like.

[0046] The ambient air heating assembly 38 is configured to receive ambient air U and to heat the ambient air U at the ambient air discharge area 42 as heated ambient air U. E In an advantageous embodiment, the ambient air heating component 38 comprises a heat exchanger 44 through which flows a cooling medium, usually a liquid cooling medium, which circulates in a cooling circuit, for example, which is assigned to the fuel cell component 14 and receives heat from the fuel cell component. For example, the heat exchanger 44 can be provided by a vehicle radiator which is present in the vehicle 12 and through which the driving wind can flow. In the heat exchanger 28, the ambient air U received from the outside receives heat from the cooling medium and is then heated as the ambient air U E Flows into the equipment space 36 .

[0047] The fuel cell exhaust gas exhaust area 34 of the fuel cell exhaust device 20 is oriented with respect to the ambient air flow direction S U The ambient air outlet region 42 is arranged downstream of the heat exchanger 38 or the ambient air outlet region 42. As a result, the heated ambient air U leaving the ambient air heating component 38 is E Along the ambient air flow direction S U The fuel cell exhaust gas A flows toward the fuel cell exhaust exhaust region 34 of the fuel cell exhaust device 20 or flows into the volume region. B Also discharged from the fuel cell exhaust gas discharge area 34 into the volume area. Therefore, in this volume area, in the design example shown in the complete equipment space 36, the fuel cell exhaust gas A B and the heated ambient air U E Mix well to form the exhaust gas A from the fuel cell B and the heated ambient air U E The mixture G is composed of.

[0048] Figure 1 Different designs of the fuel cell exhaust gas outlet region 34 or the fuel cell exhaust gas outlet opening 32 are illustrated. In the upper region of the fuel cell exhaust gas outlet region 34, the outlet opening 32 is positioned such that the fuel cell exhaust gas flow direction S BEssentially corresponds to the heated ambient air U E Ambient air flow direction S U This means that the two flow directions S U , S B In other words, the main flow directions of the two gas streams are substantially parallel and oriented in the same direction relative to each other. In the middle region of the fuel cell exhaust gas discharge region 34, the discharge opening 32 is arranged so that the battery exhaust gas flow direction S B 'Basically opposite to the ambient air flow direction S U , the two flow directions S U , S B 'Or the main flow directions of the two air flows are therefore substantially parallel to each other and point in opposite directions. Figure 1 The following figure illustrates that at such a fuel cell exhaust gas outlet opening 32, the fuel cell exhaust gas A B Instead of being discharged as essentially uniformly directed exhaust jets, the exhaust jets are discharged in a fan-shaped or cone-shaped configuration. Here, the main flow direction, which essentially corresponds to the center line of the discharge fan or discharge cone, can also be opposite to the ambient air flow direction S U Either as shown, it may be directed in the same direction as the ambient air flow direction, or it may be directed in another manner, in the direction of the ambient air flow direction S U angled (e.g., orthogonally).

[0049] It is noted that in the fuel cell exhaust gas discharge area 34, all fuel cell exhaust gases may have the previously described Figure 1 3. The fuel cell exhaust gas outlet region 34 may be provided with one of three different configurations of outlet openings 32 shown in FIG. 3 or with fuel cell exhaust gas outlet openings 32 of different configurations. It is also possible to orient the fuel cell exhaust gas outlet openings 32 or a portion of the fuel cell exhaust gas outlet openings in such a way that the heated ambient air U circulating around the fuel cell exhaust gas outlet region 34 E Transverse to the ambient air flow direction S U The release of exhaust gas A of the fuel cell is also assisted thereby B and the heated ambient air U E for releasing the fuel cell exhaust gas A B When the fuel cell exhaust gas outlet opening 32 is designed in a fan-shaped or cone-shaped configuration, the fuel cell exhaust gas outlet area 34 may have, for example, only a single fuel cell exhaust gas outlet opening 32, through which the fuel cell exhaust gas A B Basically perpendicular to the ambient air flow direction S U The two air streams pass through each other.

[0050] The fuel cell exhaust gas A can also be supplemented by a fuel cell exhaust gas / ambient air mixing assembly 46 disposed downstream of the fuel cell exhaust gas discharge region 34. B and the heated ambient air U E This fuel cell exhaust gas / ambient air mixing assembly may include one or more mixers 48, which may be configured, for example, with deflection blades for swirl or flow reversal and thereby promote mixing of the fuel cell exhaust gas A B With the heated ambient air U E Effective mixing.

[0051] By mixing the fuel cell exhaust gas A with high relative humidity B and the heated ambient air U having a relatively low relative humidity E , providing a fuel cell exhaust gas / ambient air mixture G having a relative humidity which is significantly lower than the fuel cell exhaust gas A B The relative humidity of the fuel cell exhaust gas / ambient air mixture G is significantly below 100%. If the fuel cell exhaust gas / ambient air mixture G is discharged from the complete equipment space 36 to the environment at the opening area 40 with a relative humidity that is significantly below 100%, the fuel cell exhaust gas / ambient air mixture spontaneously comes into contact with the cold ambient air U during operation when the ambient temperature is relatively low. This results in that the temperature also spontaneously decreases by mixing the fuel cell exhaust gas / ambient air mixture G and the relatively cold ambient air U. Because the relative humidity of the fuel cell exhaust gas / ambient air mixture G is significantly below 100% before this mixing with the ambient air U, there is actually no possibility that when the temperature of the fuel cell exhaust gas / ambient air mixture G drops during mixing with the cold ambient air U, the relative humidity exceeds a value of 100% and thus forms atomization through condensed water.

[0052] In order to be able to set the thermal interaction between the unheated ambient air U introduced into the heat exchanger 44 and the cooling medium in a defined manner, the heat exchanger 44 can be equipped with a throttling assembly 50. This throttling assembly can, for example, include a plurality of plates adjusted to change the flow performance upstream of the heat exchanger 44. The amount of ambient air U flowing through the heat exchanger 44 is changed by deflecting the plates and thus changing the flow performance of the throttling assembly 42. If less ambient air U is introduced into the heat exchanger 44, the heat transported in the cooling medium is transferred to a smaller amount of air, which may result in: the ambient air U leaving the heat exchanger 44 heated is E Thus, the amount of air flowing through the heat exchanger 44 on the one hand and thus the heated ambient air U leaving the heat exchanger 44 on the other hand can be adjusted. E The temperature of the fuel cell exhaust gas A BThe fuel cell exhaust gas / ambient air mixture G having the lowest possible relative humidity can thus be produced in the plant space 36 .

[0053] By exhausting the fuel cell A B and the heated ambient air U E The introduction into the plant space 36 ensures that the heated ambient air U is already present before it comes into contact with the unheated or cold ambient air U. E and fuel cell exhaust A B To this end, it is particularly advantageous that the distance a between the fuel cell exhaust gas discharge area 34 or the fuel cell exhaust gas discharge opening 32 and the ambient air discharge area 42 is not greater than 50%, preferably not greater than 10%, of the distance A between the opening area 40 and the ambient air discharge area 42, at which the fuel cell exhaust gas / ambient air mixture G is discharged into the environment and comes into contact with the cold ambient air U, for example, in the area of ​​the bottom of the vehicle 12 or in the lateral area or the rear area of ​​the vehicle. The distance a can be, for example, the distance between the fuel cell exhaust gas discharge opening 32 farthest from the ambient air discharge area 42 and the ambient air discharge area 42. The distance A can be, for example, the distance between the opening area 40 closest to the ambient air discharge area 42 and the ambient air discharge area 42.

[0054] In the case of the ambient air heating assembly 38 Figure 2 In another design variant illustrated in the figure, this ambient air heating component can have a plurality of heat exchangers 44a, 44b, 44c, through which the ambient air U to be heated flows in sequence, i.e. continuously. The heat exchangers 44a, 44b, 44c can be assigned to different cooling circuits, which can be provided for cooling different system areas independently of one another in the vehicle 12 or for maintaining them independently of one another at a defined temperature level. The heat exchanger 44a positioned most upstream that the ambient air U to be heated first encounters can be, for example, a low-temperature heat exchanger, while the heat exchanger 44b can be a medium-temperature heat exchanger and the heat exchanger 44c can be a high-temperature heat exchanger, which is provided, for example, for conducting heat away from the fuel cell assembly 14 or maintaining the fuel cell assembly at a defined temperature level. This means that the temperature of the cooling medium flowing through the heat exchangers 44a, 44b, 44c increases along the flow direction of the ambient air U to be heated. A fuel cell exhaust gas discharge area 34 is located downstream of the heat exchanger 44c having the highest cooling medium temperature for discharging the fuel cell exhaust gas A B Released to the heated ambient air U circulating around it E middle.

[0055] Figure 2Further illustration: For auxiliary support or for generating the flow of the heated or heated ambient air, an ambient air blower 52 may be provided. Thus, in particular, it can also be used to provide sufficient flow through the ambient air heating component 38 and thus to provide a sufficient amount of heated ambient air U when the vehicle 12 is stationary. E An ambient air fan 52 for generating a sufficient ambient air flow is particularly advantageous, especially if the ambient air heating assembly 38 is positioned, for example, on a bus or train or locomotive, such that it is not directly flowed into by the traffic wind.

[0056] In principle, the ambient air blower 52 can also be arranged upstream of the ambient air heating assembly 38, ie upstream of the heat exchanger or all heat exchangers thereof, but positioning it directly downstream of the fuel cell exhaust gas discharge region 34 is particularly advantageous, since the heated ambient air U is then E The vortex generated by the ambient air blower 52 assists in supporting the fuel cell exhaust gas A B Mix well. Figure 2 As shown by the dashed line in FIG. 1 , when the ambient air fan 52 moves along the heated ambient air U E This effect can also be achieved when the flow direction of the fuel cell is positioned downstream of the ambient air heating assembly 38 and upstream of the fuel cell exhaust gas exhaust area 34.

[0057] In another variant of the vehicle constructed according to the present invention, the fuel cell exhaust gas outlet region 34 and the ambient air outlet region 42 can be positioned on the vehicle 12 in such a way that they do not discharge the fuel cell exhaust gas A. B Or the heated ambient air U E Instead of releasing the two air flows into a volume area formed in the vehicle 12 and open to the environment in principle, such as the equipment space 36, the two air flows are released, for example, directly adjacent to each other, substantially directly into the environment or the unheated ambient air U, so that the two air flows are mixed substantially in the environment, that is, outside the vehicle 12. In order to ensure a sufficient reduction in the relative humidity of the fuel cell exhaust gas in this case, it is advantageous if the released heated ambient air U E The amount is significantly greater than the fuel cell exhaust gas A B The two air streams are released in this way, so that, for example, the fuel cell exhaust gas A B The flow consists of heated ambient air U E The skin vortex in the fuel cell is surrounded and released to the environment, which can also assist in supporting the exhaust gas A of the fuel cell in this design. B and the heated ambient air U E Mix thoroughly to reduce the relative humidity.

[0058] Figure 3 To illustrate this design, the ambient air heating assembly 38 and the fuel cell exhaust gas discharge area 34 are positioned so closely side by side or side by side that the air flows emitted by them are directed substantially side by side into the fuel cell exhaust gas discharge area 34. Figure 3 The volume area represented as the mixing area M in FIG. Fuel cell exhaust gas A B and the heated ambient air U E The flows pass through one another in the region of the mixing zone M, whereby a fuel cell exhaust gas / ambient air mixture G is formed.

[0059] As explained above, such a mixing zone M can be located outside the vehicle 12 , but also inside the vehicle 12 , for example in a region corresponding to the plant space 36 in the volume surrounded by the circumference of the vehicle.

[0060] Although in this embodiment the ambient air heating unit 38 or the fuel cell exhaust gas outlet region 34 are relatively energy efficient relative to each other, Figure 3 The angled positioning shown in FIG. 1 is particularly advantageous for achieving air flows passing through each other. In principle, it is also possible to arrange the ambient air heating unit 38 and the fuel cell exhaust gas discharge area 34 relative to each other so that the flow direction S B , S U Basically parallel to each other. Mainly when the mixing zone M is outside the vehicle 12, for example, below its bottom, in this design, the ambient air receiving the two air flows can cause or assist in supporting the exhaust gas A of the fuel cell. B and the heated ambient air U E The mixing of the two air flows has a relative speed that causes turbulence when the vehicle 12 is traveling.

[0061] In another alternative design, the ambient air heating assembly 38 and the fuel cell exhaust gas discharge area 34 may be arranged relative to each other such that the fuel cell exhaust gas discharge area 34 is oriented with respect to the ambient air flow direction S U The ambient air heating assembly 38 or its ambient air discharge area 42 is arranged upstream. Here, the fuel cell exhaust gas A can be guided in this way. B , so that the fuel cell exhaust gas circulates around the ambient air heating component 38, that is, for example, the heat exchanger 44, but is not heated therein. Downstream of the ambient air discharge area 42, the fuel cell exhaust gas A B and the heated ambient air U discharged at the ambient air discharge area 42 E Mix well.

Claims

1. A vehicle, comprising: A fuel cell system (10) comprising a fuel cell assembly (14) and a fuel cell exhaust gas (A) received from the fuel cell assembly (14) B ) of a fuel cell exhaust device (20), the fuel cell exhaust device (20) having a fuel cell exhaust exhaust region (34) for discharging fuel cell exhaust gas (A) from the fuel cell exhaust device (20) B ), - an ambient air heating assembly (38) for heating the exhaust gas (A) to be transported to the fuel cell B ), wherein the ambient air heating component (38) has an ambient air discharge area (42) for discharging the ambient air (U) heated in the ambient air heating component (38) E ), Features: the fuel cell exhaust gas discharge region (34) with respect to the heated ambient air (U) emitted from the ambient air heating assembly (38) at the ambient air discharge region (42); E ) of the ambient air flow direction (U S ) is positioned downstream of said ambient air exhaust region (42), or the fuel cell exhaust gas discharge region (34) with respect to the heated ambient air (U) emitted from the ambient air heating assembly (38) at the ambient air discharge region (42); E ) of the ambient air flow direction (U S ) is positioned upstream of said ambient air exhaust region (42), or / and The fuel cell exhaust gas discharge area (34) and the ambient air discharge area (42) are positioned so that the fuel cell exhaust gas (A) discharged at the fuel cell exhaust gas discharge area (34) is B ) and the heated ambient air (U ) discharged at the ambient air discharge area (42) E )'s flows at least partially pass through each other.

2. The vehicle according to claim 1, characterized in that The ambient air heating assembly (38) has at least one heat exchanger (44) through which ambient air (U) to be heated and a cooling medium flowing in a cooling circuit can flow, the heat exchanger being used to transfer heat contained in the cooling medium to the ambient air (U) to be heated.

3. The vehicle according to claim 2, characterized in that The ambient air heating component (38) comprises a plurality of heat exchangers (44a, 44b, 44c) through which the ambient air (U) to be heated can flow continuously, and the fuel cell exhaust gas discharge area (34) is preferably positioned downstream of the heat exchanger (44c) positioned most downstream of the plurality of heat exchangers (44a, 44b, 44c) with respect to the flow direction of the ambient air (U) to be heated.

4. The vehicle according to any one of claims 1 to 3, characterized in that The ambient air heating component (38) is provided with a throttle component (50) for throttling the amount of ambient air (U) to be heated that flows through the ambient air heating component (38).

5. The vehicle according to any one of claims 1 to 4, characterized in that The fuel cell exhaust gas discharge region (34) has at least one fuel cell exhaust gas discharge opening (32).

6. The vehicle according to claim 4, characterized in that: - at least one, preferably each fuel cell exhaust gas outlet opening (32) is configured to be arranged to flow in a direction substantially corresponding to the direction of flow of the ambient air (S U ) of the fuel cell exhaust gas flow direction (S B ) Release fuel cell exhaust gas (A B ), or / and - at least one, preferably each fuel cell exhaust gas outlet opening (32) is configured to be discharged in a direction substantially opposite to the direction of flow of the ambient air (S U ) of the fuel cell exhaust gas flow direction (S B ') Release fuel cell exhaust (A B ), or / and At least one, preferably each fuel cell exhaust gas outlet opening (32) is designed to emit a fuel cell exhaust gas flow that expands in a fan-shaped or cone-shaped manner.

7. The vehicle according to any one of claims 1 to 6, characterized in that Regarding the ambient air flow direction (S U ) A mixing assembly (46) having at least one ambient air / fuel cell exhaust gas mixer (48) is arranged downstream of the fuel cell exhaust gas discharge region (34).

8. The vehicle according to any one of claims 1 to 7, characterized in that The ambient air outlet area (42) is configured to discharge the heated ambient air (U E ) is discharged into a plant space (36) of the vehicle (12) which is open to the environment via at least one opening area (40), and the fuel cell exhaust gas discharge area (34) is configured to discharge the fuel cell exhaust gas (A B ) is released into the complete equipment space (36).

9. The vehicle according to claim 8, characterized in that The distance (a) between the fuel cell exhaust gas discharge area (34) and the ambient air discharge area (42) is less than 50%, preferably less than 10%, of the distance (A) between the at least one opening area (40) and the ambient air discharge area (42).

10. The vehicle according to the preamble of claim 1 or any one of claims 1 to 9, characterized in that The ambient air heating component (38) is equipped with an ambient air fan (52) for conveying the ambient air to be heated (U) and / or the heated ambient air (U E ), and the ambient air fan (52) is arranged with respect to the ambient air flow direction (U S ) is arranged downstream of the ambient air heating component (38).

11. The vehicle according to claim 10, characterized in that The ambient air fan (52) is arranged with respect to the ambient air flow direction (U S ) is arranged downstream of the fuel cell exhaust gas discharge area (34).

12. The vehicle according to any one of claims 1 to 11, characterized in that The fuel cell exhaust device (20) comprises a fuel cell exhaust treatment component (22), wherein the fuel cell exhaust treatment component (22) comprises at least one of the following structural components: - a liquid separator (24), - Catalyst (26), -Muffler (28).

13. A method for operating a fuel cell system in a vehicle, the vehicle preferably being a vehicle according to any one of claims 1 to 12, in which method a fuel cell exhaust gas (A) is generated from ambient air (U) and a fuel cell exhaust gas outlet region (34) of a fuel cell exhaust gas device (20) associated with a fuel cell component (14) of the fuel cell system. B ) is mixed with the exhaust gas (A) of the fuel cell. B ) of the ambient air (U) in contact with the fuel cell exhaust gas (A B ) Heat before mixing.

14. The method according to claim 13, characterized in that The heated ambient air (U E ) and the fuel cell exhaust gas (A B ) is discharged into an equipment space (36) of the vehicle (12) which is open to the environment, and essentially forms a fuel cell exhaust gas (A) in the equipment space (36). B ) and heated ambient air (U E ) is a mixture (G).

15. The method according to claim 13 or 14, characterized in that The fuel cell exhaust gas (A B ) mixed with heated ambient air (U E ) is heated in at least one heat exchanger (44) by thermal interaction with a cooling medium flowing in a cooling circuit of the vehicle (12).

16. The method according to claim 15, characterized in that The mass flow of the ambient air (U) flowing through the at least one heat exchanger (44) and / or the mass flow of the cooling medium flowing through the at least one heat exchanger (44) is varied in order to set the temperature of the ambient air (U) to be heated in the at least one heat exchanger.

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