Fuel cell system with humidification through a nozzle
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-06
- Publication Date
- 2026-08-13
Smart Images
Figure EP2026053126_13082026_PF_FP_ABST
Abstract
Description
[0001] Woodward L'Orange GmbH February 6, 2026 F&R Ref.: 46715-0182WO1
[0002] Fuel cell system
[0003] The invention relates to a fuel cell system of the type specified in the preamble of claim 1.
[0004] Fuel cell systems are generally well-known. For example, they are used in motor vehicles to power them. Their applications are diverse.
[0005] Fuel cell systems can also be used as electrochemical filters. These systems typically consist of multiple fuel cells arranged in a stack. Each fuel cell has a semi-permeable membrane through which protons from a fuel are released at the anode and migrate to the cathode, which is separated from the anode by the membrane. Meanwhile, electrons flow from the anode to the cathode via an electrical circuit, powering a load such as an electric motor. However, if the membrane becomes too dry, the fuel cell's performance is impaired, thus reducing the overall efficiency of the fuel cell system.
[0006] This means that the individual membranes must be kept moist to ensure optimal conductivity and diffusion of hydrogen through the membrane. If the membranes are too dry, their proton conductivity is reduced. Furthermore, sufficient membrane humidification extends the lifespan of the fuel cell, as an excessively dry membrane can lead to damage and failure.
[0007] Overall, membrane humidification is an important factor for the performance and efficiency of fuel cells and plays a crucial role in their use as a clean and efficient energy source.
[0008] There are various approaches to humidifying the membranes, with passive and active humidification being the most common methods. Passive humidification means that the moisture in the fuel cell comes from the fuel supplied or the ambient air. However, this method is often insufficient because the membranes require a certain minimum humidity to operate effectively. Therefore, most fuel cell systems employ active humidification.
[0009] A common method for active humidification is a so-called membrane humidifier. The membrane humidifier works by exchanging moisture between a moist exhaust gas cathode of the fuel cell and a dry intake air cathode. The exhaust gas of the fuel cell contains water vapor, which is produced by the reaction of hydrogen and oxygen. This water vapor is transferred by the membrane humidifier to the dry fresh air side of the fuel cell, where it humidifies the membranes.
[0010] The anode strand can also be moistened in this way.
[0011] One disadvantage of membrane humidifiers is their often large size, making them difficult to integrate and resulting in additional costs and complexity. Structural problems and limitations of this humidification technology arise, particularly when scaling up. A promising alternative to membrane humidification, which can also be combined with smaller membrane humidifiers, is direct water injection into the fuel cell's cathode string after a compressor. Direct water injection can be implemented using pressure nozzles or other injection technologies. Compared to membrane humidifiers, this method has the significant advantage that the air after compression in the cathode string does not need to be cooled; instead, it is used to evaporate the injected water.
[0012] For example, a fuel cell system with a membrane humidifier can be taken from the patent application DE 102022214241 A1, in which a direct injection system is provided in addition to the membrane humidifier.
[0013] The object of the present invention is to provide an improved fuel cell system. This object is achieved according to the invention with a fuel cell system having the features of claim 1. Advantageous embodiments with expedient and non-trivial further developments of the invention are specified in the dependent claims.
[0014] A fuel cell system according to the invention, comprising at least one fuel cell, has a housing that is fluidically connected to an anode strand and a cathode strand of the fuel cell system, wherein a nozzle head of a single-injection device of the fuel cell system is arranged in the fluid-flowable anode strand and / or in the fluid-flowable cathode strand. According to the invention, to effect the vaporization of an injection fluid which is injected into the anode strand and / or into the cathode strand, the nozzle head is configured to have a plurality of holes, wherein one hole of the plurality of holes is configured to generate an initial droplet, wherein the initial droplet has a Sauter diameter of less than or at most 100 pm.The advantage of the invention lies in the fact that, with the aid of such a nozzle head, rapid vaporization of the injected injection fluid, which is usually water, can be achieved in the corresponding strand. If the nozzle head is arranged in the anode strand, rapid vaporization of the injected injection fluid can be achieved within the flow of the anode fluid in the anode strand, and if the nozzle head is arranged in the cathode strand, rapid vaporization of the injected injection fluid can be achieved within the flow of the cathode fluid in the cathode strand.
[0015] In this method, the injection fluid is injected directly into the cathode and / or anode string to moisten the fuel cell membrane. One of the main advantages of this so-called direct injection with the nozzle head described above, which is designed as a pressure nozzle, is its high efficiency. Direct injection introduces the injection fluid directly into the cathode and / or anode string, where it comes into contact with the membrane and moistens it. This allows for load-adapted membrane moistening, resulting in higher fuel cell performance and efficiency, and consequently, higher performance and efficiency of the entire fuel cell stack. In other words, it increases the efficiency of the fuel cell system.The operating-point-dependent controllability of the humidification is a clear conceptual advantage over non-adjustable fixed-geometry membrane humidifiers, which typically introduce too much moisture at low airflows and too little at high airflows. Particularly in conjunction with selected nozzle head designs, uniform membrane humidification can be achieved, contributing to high efficiency and a long service life for the fuel cell. Sufficient membrane humidification is crucial to prevent damage and failure of the fuel cell and fuel cell system.
[0016] Compared to a known fuel cell system with conventional membrane humidification or with known pressure atomizers, the fuel cell system according to the invention offers cost and space advantages, as these are lower than in the known systems. Furthermore, it offers very good scalability.
[0017] A realization of the Sauter diameter of the initial droplet with a maximum size of 100pm can be advantageously achieved if the hole diameter has a value of at most 100pm.
[0018] An advantageous method for producing the hole with a diameter of at most 100 pm is a laser process. Compared to drilling or punching, no burrs are formed at the hole, thus ensuring that the Sauter diameter of the injection fluid is less than or at most 100 pm. It should be noted that the injection fluid must be selected depending on the anode and cathode fluids. If the anode fluid is hydrogen and the cathode fluid is air, particularly oxygen, then water is preferable as the injection fluid.
[0019] Provided that the nozzle head has a head diameter which, when the nozzle head is arranged in the anode strand, corresponds to an inner diameter of the anode strand, or when the nozzle head is arranged in the cathode strand, corresponds to an inner diameter of the cathode strand, the advantage is that the injection of the injection fluid can be formed over a large area and uniformly in the anode strand or cathode strand.
[0020] It should be noted here that a diameter does not necessarily refer to the diameter of a circle. While circular cross-sections for the anode and cathode strands are generally assumed, as this is the simplest and most cost-effective way to manufacture them, these strands could also have a cross-section other than a circle. Therefore, in this context, any cross-section with a mean cross-section corresponding to the mean cross-section of a circular strand should be understood as having a diameter. This also applies to the concept of diameter.
[0021] To achieve rapid atomization, the nozzle head can have a first head section with numerous holes, which can be star-shaped, ring-shaped, or spiral. Depending on this, a second head section of the nozzle head is designed through which the injection fluid is fed to the first head section. Overall, the nozzle head should result in minimal flow disturbance and pressure drop in the strand in which it is located, i.e., the cathode strand or the anode strand. For example, the least resistance is generated by a coaxial feed of the injection fluid into the first head section, coaxial with a longitudinal axis of the corresponding strand, as can be achieved with a star-shaped or spiral first head section.If the first head section is ring-shaped, an accumulation and coagulation of droplets of the injection fluid in the area of a nozzle inlet of the nozzle head, which marks a connection of the second head section to the first head section, can be prevented.
[0022] The multitude of holes can be configured in the direction of, against the direction of, and / or perpendicular to the flow of the anode fluid and / or cathode fluid at the nozzle head. Individual strands of holes in the nozzle head, which feature the multitude of holes, ensure a uniform distribution of droplets across the cross-section of the anode or cathode strand, thus guaranteeing uniform wetting of the membrane. The holes of the multitude can be located on the front, side, or rear. They can be arranged in various configurations relative to each other. They could also have different hole diameters. This can be advantageous, for example, if the flow in the anode or cathode strand is unevenly distributed across its cross-section due to unsuitable anode or cathode strand geometry.
[0023] To improve flow around the nozzle head, the numerous holes in at least one of the nozzle head's perforations are designed with a wing-like profile. This wing-like profile optimizes the flow around the nozzle head, thereby reducing flow disturbances, such as turbulence, and pressure drops resulting from the nozzle head's positioning within the anode fluid and / or cathode fluid flow.
[0024] During operation of the fuel cell system (or during its intended use), the injection fluid is subjected to a pressure, which is hereinafter referred to as the injection pressure. This pressure can, of course, be very high to achieve rapid vaporization, for example, 100 bar, but preferably also a lower value, in particular a maximum of 10 bar. Since less energy is required to achieve a low injection pressure compared to a high injection pressure, a cost-effective fuel cell system can thus be realized using a low injection pressure, especially one of 10 bar. For example, the injection pressure could result from a combination with an electrolyzer, from which the injection fluid can be drawn.
[0025] Advantageously, the injection device includes a pump upstream of the nozzle head. The pump is preferably configured to generate the injection pressure. The pump is preferably integrated into a supply line of the injection device, which serves to supply the injection fluid to the nozzle head. This preferably generates a pressure with a maximum value of no more than 100 bar. If it has a maximum value of no more than 50 bar, and particularly preferably no more than 10 bar, this contributes to making the injection of the injection fluid, which corresponds to direct injection, with the nozzle head cost-effective.
[0026] Fuel cell systems typically include a water tank, as water is the end product of the cold combustion process. If water is suitable as the injection fluid, it is cost-effective to design the injection unit to be connected to the water tank in a flow-through manner, as the water can be introduced into the membrane's humidification system and thus circulate within the fuel cell system.
[0027] When elements of the fuel cell system are described as being connected in a way that allows fluids to flow between them, this means that they are fluid-connected. In other words, the elements are connected in such a way that fluids can flow between them.
[0028] If a heating element is provided upstream of the nozzle head to heat the injected fluid, such as water, very good atomization of the injection jet can be achieved. This prevents droplets of the injection fluid from accumulating in the cathode and / or anode strand of the fuel cell system and reducing its efficiency. The heating element can be active, for example, in the form of a heating sleeve or tank heater, or it can be passive, for example, in the form of a heat exchanger.
[0029] Additionally or alternatively, a (further) heating unit can be provided in the fuel cell system, configured to heat the anode string and / or the cathode string. This means that this heating unit can heat all the fluid flowing through the respective string. This heating unit can also be active, for example, in the form of a heating jacket. It can also be passive, for example, in the form of a heat exchanger. Additionally or alternatively, a (further) heating unit can be provided in the fuel cell system, configured to heat an anode outlet and / or an anode recirculation path. This means that this heating unit can heat all the fluid flowing through the anode outlet or the anode recirculation path. In this context, the anode outlet refers to the line or string through which the anode exhaust gas, which may also contain liquid components, leaves the anode.The anode recirculation path refers to the line or string through which the anode exhaust gas, which may also contain liquid components, leaves the anode in order to be at least partially returned to the anode (via at least part of the anode string).
[0030] To reduce pressure losses, a pressure loss-reducing unit can be formed downstream of the nozzle head and directly adjacent to it. This unit is designed as a nozzle outlet, particularly in the form of a Laval nozzle. This allows pressure losses in the flow, as determined by the arrangement of the nozzle head, thus in the anode or cathode branch of the fuel cell system according to the invention, to be reduced, and a uniform droplet distribution across the flow cross-section can be achieved.
[0031] The fuel cell disclosed herein can be used to generate electrical energy by means of cold combustion. Alternatively or additionally, the fuel cell can be used as an electrochemical filter (for example, in a recirculation path of another fuel cell). The possible applications are examples, and the fuel cell or fuel cell system disclosed herein is not limited to them.
[0032] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention. Identical or functionally equivalent elements are assigned identical reference numerals. Figure 1 shows a basic representation of a fuel cell system according to the invention with a fuel cell.
[0033] Fig. 2 shows a schematic representation of a cathode string with a nozzle head of a single-nozzle device of the fuel cell system according to a first embodiment according to the invention.
[0034] Fig. 3a) shows in a general representation the nozzle head of the fuel cell system according to the invention in the first embodiment in a front view,
[0035] Fig. 3b) shows a schematic representation of the nozzle head of the fuel cell system according to the first embodiment in a side view, Fig. 4 shows a schematic representation of the nozzle head of the fuel cell system according to a second embodiment in a top view, Fig. 5a) shows a schematic representation of the nozzle head of the fuel cell system according to a third embodiment in a side view,
[0036] Fig. 5b) shows in a general representation the nozzle head of the fuel cell system according to the third embodiment in a front view,
[0037] Fig. 6a) shows in a schematic representation the nozzle head of the fuel cell system according to the invention in a fourth embodiment in a side view,
[0038] Fig. 6b) shows in a general representation the nozzle head of the fuel cell system according to the fourth embodiment in a front view,
[0039] Fig. 7 shows a top view of a perforated section of the nozzle head of the fuel cell system according to a fifth embodiment, Fig. 8 shows a schematic view of the nozzle head of the fuel cell system according to the invention in different orientations in the anode section, Fig. 9 shows a schematic view of the nozzle head according to Fig. 2 with a distribution structure over a cross-section of the cathode section, and
[0040] Fig. 10 shows in principle the nozzle head of the fuel cell system according to a sixth embodiment with the distribution structure over the cross-section of the cathode string.
[0041] Figure 1 illustrates a fuel cell 1 of a fuel cell system 2 according to the invention in a schematic diagram. The fuel cell system 2 of the embodiments described here comprises several fuel cells 1, which are arranged in the form of a stack in a housing 3 of the fuel cell system 2. Naturally, the fuel cell system 2 could also have only one fuel cell 1.
[0042] The fuel cell system 2, which is presented here as a purely exemplary configuration for generating electrical energy by means of cold combustion, serves as an energy supplier for, for example, an electric motor M, and can, for example, form a drive system for a motor vehicle in conjunction with the electric motor M. Naturally, the fuel cell system 2 according to the invention can also be used in stationary power plants or in ships. Numerous applications of the fuel cell system 2 are conceivable.
[0043] The fuel cell 1 has an anode 5 and a cathode 6 in its cell housing 4, which are connected to each other by means of a conductive connection 7, for example, a conductive cable, to generate electrical energy. The anode 5 and the cathode 6 are housed in the cell housing 4, which is divided into a first housing part 9 and a second housing part 10 by means of a membrane 8. The anode 5 is housed in the first housing part 9, where it is at least partially surrounded by an anode fluid 11. Similarly, the cathode 6 is located in the second housing part 10, where it is at least partially surrounded by a cathode fluid 12. The membrane 8 is permeable to ions, allowing them to pass through the membrane 8 into the second housing part 10.In the present embodiments, the anode fluid 11 is hydrogen and the cathode fluid 12 is oxygen, which together lead to an end product water via cold combustion, which can flow out of the housing 3 via an outlet A.
[0044] The membrane 8 must be kept moist to ensure optimal conductivity and diffusion of hydrogen through it. If the membrane 8 is too dry, its proton conductivity will be reduced. Therefore, the fuel cell system 2 according to the invention has a single-nozzle device 13 with a nozzle head 14, as illustrated in a schematic diagram in Fig. 2.
[0045] In the present embodiment, the nozzle head 14 is received in a cathode strand 16 that is connected to the housing 3 and through which fluid flows. It should be noted that the nozzle head 14 could also be received in an anode strand 15 that is connected to the housing 3 and through which fluid flows. The cathode fluid 12, in this embodiment air, is supplied to the first housing part 9 via the cathode strand 16. Hydrogen is supplied to the anode strand 15.
[0046] To supply the nozzle head 14 with an injection fluid used to moisten the membrane 8, the injection device 13 has a reservoir 23 through which a supply line 22 of the injection device 13 is also connected to the nozzle head 14. In other words, a flow-through supply line 22 is provided between the nozzle head 14 and the reservoir 23 so that the injection fluid can be supplied from the reservoir 23 to the nozzle head 14 for atomization. In the present embodiments, the injection fluid is water.
[0047] To effect particularly rapid evaporation of the injection fluid, i.e., in the present embodiments, the water injected into the anode string 15 to moisten the membrane 8, the nozzle head 14 has a plurality of holes 17, wherein one hole 18 of the plurality of holes 17 is designed to produce an initial droplet 21 with a so-called Sauter diameter SD. The Sauter diameter SD has a value that is less than or at most 100 pm. Such a Sauter diameter SD can preferably be realized with a hole diameter DL of the individual hole 18 of the plurality of holes 17, which has a value of at most 100 pm.
[0048] The nozzle head 14 has a first head section 19, which has the plurality of holes 17, and a second head section 20, which is designed to supply water to the first head section 19 and is connected to the supply line 22 by means of flow.
[0049] Figure 2 shows a schematic representation of the cathode string with the nozzle head 14 of the single-injection device 13 of the fuel cell system 2 according to a first embodiment of the invention. It should be noted that the nozzle head 14 can also be described as a shower head nozzle, since it has a plurality of holes 17, similar to a shower head.
[0050] The nozzle head 14 according to the first embodiment, as shown in Fig. 2, is illustrated in Fig. 3a) in a general front view and in Fig. 3b) in a side view.
[0051] The first head section 19, which has a head diameter DK, is star-shaped according to the first embodiment of the fuel cell system 2 according to the invention. In the present embodiment, it has eight strands of holes 24, each with holes 8, wherein the ends 25 of the strands facing each other are connected to each other and form a nozzle inlet 26, which is designed to allow flow through the second head section 20. The second head section 20 can be described as lance-shaped in this embodiment.
[0052] The holes 18 are preferably distributed over a lateral surface 31 of the perforated strand 24. In other words, the plurality of holes 17, which constitute a set of holes 18 of the perforated strands 24, can be arranged both on an end face 27 of the nozzle head 14 facing away from the second head section 20, and on side faces 28 of the perforated strands 24 extending transversely to the end face 27, as well as on a back face 29 of the nozzle head 14 facing away from the end face 27. To achieve preferred atomization, the perforated strand 24 is to be designed with the smallest possible thickness 30. This means that the two side faces 27 of the perforated strand 24 are to be arranged as close together as possible.
[0053] The first head section 19 could, for example, also be spirally shaped, as illustrated in a schematic diagram in Fig. 4 in a second embodiment of the fuel cell system 2 according to the invention. It can be formed from a single strand of holes 24, which is spirally shaped along its longitudinal extent. The plurality of holes 17 are also arranged distributed over the outer surface 31 of the strand of holes 24.
[0054] In principle, to achieve rapid evaporation of the injected water, it is advantageous if the nozzle head diameter DK corresponds to the inner diameter DIA of the anode strand when the nozzle head 14 is arranged in the anode strand 15, or, if the nozzle head 14 is arranged in the cathode strand 16, to the inner diameter DIK of the cathode strand. In other words, the first nozzle head section 19 must at least partially encompass the flow cross-section of the corresponding strand 15; 16 around its circumference.
[0055] Figures 5a), 5b), 6a), and 6b) show the nozzle head 14 of the fuel cell system 2 according to the invention in a third and a fourth embodiment, respectively. In both embodiments, the second head section 20 is designed in an annular shape, so that the water can flow into the first head section 19 via the nozzle inlet 26 formed on an outer circumferential surface 32 of the second head section 20.
[0056] The first head section 19 of the nozzle head 14 according to the third embodiment of the fuel cell system 2 according to the invention, as illustrated in principle in Figures 5a) and 5b) in a side view and a front view respectively, is designed in a star shape according to the first head section 19 of the nozzle head 14 of the first embodiment, wherein the water to flow out via the perforated strands 24 is fed into the perforated strand 24 at a further strand end 33 of the perforated strand 24, which is designed facing away from the strand end 25. In an embodiment not shown in detail, the first head section 19 is designed essentially according to the head section 19 of the third embodiment, but the perforated strands 24 are not connected to each other at the strand end 25 in a way that allows flow, but the perforated strands 24 form a circular ring.This means that the perforated strands 24 are shorter in their extension to a longitudinal axis 39 of the cathode strand 16, or if the nozzle head 14 is formed in the anode strand 15, to the longitudinal axis 39 of the anode strand 15, so that the first head section 19 is freely permeable in its center.
[0057] The first head section 19 of the nozzle head 14 is designed in the form of a circular ring, as shown in Figures 6a) and 6b) of the fuel cell system 2 according to the invention. The plurality of holes 17 are located on the front face 27, the back face 29, and on an inner annular surface 34 of the first head section 19. The nozzle inlet 26 can be fully formed on the outer annular surface 35 of the first head section 19, but it could also be formed only in sections, i.e., as a circular segment in sections.
[0058] Figure 7 shows a schematic top view of the perforated section 24 of the nozzle head 14 of the fuel cell system 2 according to a fifth embodiment. The perforated section 24 of the first head section 19, and thus the perforated section 24 of the nozzle head 14, has a wing-like profile 36 to achieve optimized airflow. In the first and third embodiments, the perforated sections 24 are designed with this profile 36. Similarly, the spiral nozzle head 14 according to the second embodiment can have the profile 36 over a cross-section of the spiral. By way of example, holes 18 of the plurality of holes 17 are shown, and it can be seen that the holes 18 are designed for water injection in the flow direction, i.e., along the arrow, and perpendicular to the flow direction, i.e., transverse to the arrow.Or in other words, it is the multitude of holes 17 formed in the direction and / or across the flow of the cathode fluid 12 and / or the anode fluid 11 at the nozzle head 14.
[0059] The nozzle head 14 can be installed in the anode strand 15 or the cathode strand 16 in different orientations, as shown in Fig. 8. That is, the nozzle head 14 can be oriented in the direction of the inflow of the cathode fluid 12 or the anode fluid 11, or opposite to it. It could also be configured in any conceivable intermediate position perpendicular to the direction of inflow of the fluid 11; 12. In other words, the end face 27 of the nozzle head 14 is arranged in the direction or against the flow of the cathode fluid 12 in the cathode strand 16 and / or in the direction or against the flow of the anode fluid 11 in the anode strand 15.
[0060] It should be mentioned at this point that at least two injection devices 13 could also be arranged in the fuel cell system 2 according to the invention, one injection device 13 in the anode string 15 and one injection device 13 in the cathode string 16.
[0061] To reduce pressure losses in the flow of the fluid 11; 12 in their strand 15; 16, it is advantageous to arrange a pressure loss-reducing unit 38 downstream of the nozzle head 14 and directly adjacent to the nozzle head 14. Thus, in Fig. 10, the nozzle head 14, comprising the unit 38 according to a sixth embodiment of the fuel cell structure 2 according to the invention, is illustrated.
[0062] The pressure loss-reducing unit 38 can have different shapes; it could also be designed in the form of an additional fluid injection. In the present sixth embodiment of the fuel cell system 2 according to the invention, the unit 38 is designed in the form of a Laval nozzle. To better illustrate the mode of operation of the unit 38, Fig. 9, which shows the nozzle head 14 of the fuel cell structure 2 according to the first embodiment, depicts its distribution structure 37 over a cross-section Q of the cathode strand 16. The distribution structure 37 is a distribution of the initial droplets 21 of the water injected into the cathode strand 16 by means of the nozzle head 14. A significantly more homogeneous distribution structure 37 over the cross-section Q can be achieved with the aid of the pressure loss-reducing unit 38, as can be seen in the distribution structure 37 in Fig. 10 in comparison with the distribution structure 37 in Fig. 16.9 makes clear. The injection fluid, thus the cathode fluid 12 if the nozzle head 14 is arranged in the cathode strand 16, or the anode fluid 11 if the nozzle head 14 is positioned in the anode strand 15, has an injection pressure with a value of at most 100 bar, but preferably at most 10 bar.
[0063] The single-injection device 13 can advantageously include a pump (not shown) upstream of the nozzle head 14 to achieve the desired injection pressure. The pump can operate at maximum pressures of up to 100 bar, or even exceed this pressure. However, particularly in combination with the single-injection device 13 described above, it can also operate at a maximum pressure significantly lower than 100 bar, for example, only 10 bar or even less. This means that, due to the single-injection device 13 described above, and especially due to the nozzle head 14 described above, even very low pump pressures are sufficient to achieve adequate wetting of the diaphragm 8. This helps to keep the single-injection device 13 cost-effective and thus contributes to a cost-effective fuel cell system 2.
[0064] The fuel cell system 2 according to the invention, illustrated in Fig. 2 in the first embodiment, comprises the injection device 13 with the reservoir 23, which is filled with the water to be injected. The end product of the cold combustion of the fuel cell 1 is water, which is discharged via outlet A. To utilize the discharged water, the reservoir 23 could be connected to outlet A by way of flow. Alternatively, the fuel cell system 2 could have a water tank (not shown) connected to outlet A by way of flow, and the reservoir 23 could be connected to the water tank by way of flow. Naturally, the reservoir 23 could also correspond to the water tank, provided the injection fluid is water. In this way, the end product water produced by the cold combustion would be reused in a cost-effective manner.
[0065] In another embodiment, not shown in detail, a heating unit (not shown in detail) is formed upstream of the nozzle head 14 in the injector assembly 13, with the aid of which the water to be injected can be heated. In the exemplary embodiments described above, the plurality of holes 17 is distributed over the outer surface 31 of the row of holes 24. It is self-evident that the plurality of holes 31 could also be formed only on the end face 27, or on one of the side faces 28, or on the back face 29. It could also be formed on the end face 27 and on one or both of the side faces 28, or on the end face 27 and the back face 29. Further combinations of the surfaces 27, 28, 29, which have the plurality of holes 31, are conceivable.
[0066] The fuel cell system 2 according to the invention can be combined with a conventional small membrane humidifier for the injection device 13, which comprises the pressure nozzle 14 and can also be referred to as direct injection, or in conjunction with water as direct water injection, in order to optimally cover all operating points of the fuel cell system 2 and to utilize the advantages of both humidification technologies. Reference numeral list
[0067] 1 fuel cell
[0068] 2 Fuel cell system 3 Housing
[0069] 4 cell casings
[0070] 5 Anode
[0071] 6 Cathode
[0072] 7 connection
[0073] 8 Membran
[0074] 9 First housing part 10 Second housing part 11 Anode fluid
[0075] 12 Cathode fluid
[0076] 13 Single-injector device
[0077] 14 nozzle heads
[0078] 15 anode strand
[0079] 16 Cathode strand
[0080] 17 Variety of holes 18 Hole
[0081] 19 First head section 20 Second head section 21 Initial drop
[0082] 22 Supply line
[0083] 23 Reservoir
[0084] 24-hole strand
[0085] 25 strand ends
[0086] 26 Nozzle inlet
[0087] 27 Front surface
[0088] 28 side surface
[0089] 29 Back surface
[0090] 30 thickness
[0091] 31 Surface area
[0092] 32 External perimeter area
[0093] 33 Further strand end
[0094] 34 Inner ring surface
[0095] 35 Outer ring surface
[0096] 36 Profile
[0097] 37 Distribution structure
[0098] 38 Pressure loss reducing unit 39 Longitudinal axis
[0099] A Exit
[0100] DIA Anode strand inner diameter DI K Cathode strand inner diameter DK Head diameter DL Hole diameter M Electric motor Q Cross-section
[0101] SD Sauter diameter
Claims
Woodward L'Orange GmbH February 6, 2026 F&R Ref.: 46715-0182WO1 Patent claims 1. Fuel cell system (2), comprising at least one fuel cell (1), wherein the fuel cell system (2) has a housing (3) which is fluidically connected to an anode string (15) and a cathode string (16) of the fuel cell system (2), wherein a nozzle head (14) of a single-nozzle device (13) of the fuel cell system (2) is arranged in the fluid-flowable anode string (15) and / or in the fluid-flowable cathode string (16), characterized by the fact that to bring about the evaporation of an injection fluid, which is injected into the anode strand (15) and / or into the cathode strand (16) by means of the injection device (13), the nozzle head (14) has a plurality of holes (17), wherein one hole (18) of the plurality of holes (17) is designed to generate an initial droplet (21), wherein the initial droplet (21) has a Sauter diameter (SD) with a value less than or at most equal to 10 Opm.
2. Fuel cell system (2) according to claim 1 , characterized by the fact that a hole diameter (DL) of the hole (18) has a value of at most 100pm.
3. Fuel cell system (2) according to claim 1 or 2, characterized by the fact that the hole (18) is a hole produced using a laser process.
4. Fuel cell system (2) according to one of the preceding claims, characterized in that the nozzle head (14) has a head diameter (DK), wherein the head diameter (DK) in an arrangement of the nozzle head (14) - in the anode strand (15) an anode strand inner diameter (DIA), and / or - in the cathode strand (16) corresponds to a cathode strand inner diameter (DIK).
5. Fuel cell system (2) according to one of the preceding claims, characterized in that the nozzle head (14) has a first head section (19) having a plurality of holes (17), which is star-shaped or ring-shaped or spiral-shaped.
6. Fuel cell system (2) according to one of the preceding claims, characterized in that the multitude of holes (17) are formed in the direction and / or against the direction and / or perpendicular to the direction of a flow of the anode fluid (11) and / or the cathode fluid (12) at the nozzle head (14).
7. Fuel cell system (2) according to one of the preceding claims, characterized in that the nozzle head (14) has a wing-like profile (36).
8. Fuel cell system (2) according to one of the preceding claims, characterized in that a front surface (27) of the nozzle head (14) is arranged in the direction or against the direction of a flow of the anode fluid (11) in the anode strand, and / or in the direction or against the direction of a flow of the cathode fluid (12) in the cathode strand (12).
9. Fuel cell system (2) according to one of the preceding claims, characterized in that, during operation of the fuel cell system (2), the injection fluid (12; 11) has an injection pressure with a value of at most 100 bar.
10. Fuel cell system (2) according to claim 9, characterized by the fact that The injection pressure has a value of no more than 10 bar.
11. Fuel cell system (2) according to one of the preceding claims, characterized in that The injector device (13) has a pump upstream of the nozzle head (14).
12. Fuel cell system (2) according to one of the preceding claims, characterized in that the fuel cell system (2) has a water tank (23), wherein the injector device (13) is fluidly connected to the water tank (23).
13. Fuel cell system (2) according to one of the preceding claims, characterized in that a heating unit is provided upstream of the nozzle head (14) which is configured to heat the injection fluid; and / or wherein the fuel cell system (2) comprises a heating unit configured to heat the anode string (15) and / or the cathode string (16); and / or wherein the fuel cell system (2) comprises a heating unit configured to heat an anode outlet and / or an anode recirculation path.
14. Fuel cell system (2) according to one of the preceding claims, characterized in that downstream of the nozzle head (14) and immediately adjacent to the nozzle head (14) a pressure loss reducing unit (38) is formed.
15. Fuel cell system (2) according to claim 14, characterized by the fact that the pressure loss reducing unit (38) is designed in the form of a Laval nozzle.