Operating media supply unit for a fuel cell stack

Abstract

The invention relates to an operating media supply unit (100) for a fuel cell stack (300). The operating media supply unit (100) has operating media discharge lines (121, 122, 123) for discharging fluid operating media from the fuel cells (360) of the fuel cell stack (300) and has operating media supply lines (111, 112, 113) for supplying fluid operating media to the fuel cells (360) of the fuel cell stack (300). The operating media supply lines (111, 112, 113) have a coolant supply line (113) and a cathode feed gas supply line (111) which are coupled to one another in a heat-transferring manner via a heat transfer portion (130) in order to change the temperature of a cathode feed gas (KZG) which is conducted, as one of the operating media, in the cathode feed gas supply line (111) to the fuel cell stack (300). The invention further relates to a fuel cell system (400) having a fuel cell stack (300) which is fluidically connected to the operating media supply unit (100) for the supply and discharge of the operating media. The invention further relates to a method for controlling the temperature of the cathode feed gas in the operating media supply unit (100), wherein the line portion of the coolant supply line (113) has a cross-sectional profile of which the cross-sectional area decreases, in relation to to the cross-sectional area at the external connection (140), with increasing proximity to the stack connection (150).

Description

[0001] PP34505WO / bg October 15, 2025 AVL List GmbH

[0002] Operating media supply unit for a fuel cell stack

[0003] The present invention relates to an operating media supply unit for a fuel cell stack and a fuel cell system with at least one such fuel cell stack.

[0004] Fuel cells play a crucial role in the emission-free generation of electrical energy. In a fuel cell, hydrogen and oxygen are converted into water, releasing thermal and electrical energy in the process. This electrical energy can be extracted and used as electricity. To increase power output, multiple fuel cells are stacked, connected in series, and operated in parallel. Various fuel cell types can be used, such as PEM fuel cells, which utilize a polymer electrolyte membrane (PEM), or solid oxide fuel cells (SOFCs), which use a membrane made of a ceramic material permeable to oxygen ions as their electrolyte.

[0005] To operate fuel cells, it is necessary to provide operating fluids such as hydrogen, oxygen, and coolant for stack cooling. Therefore, in addition to the fuel cells themselves, a fuel cell system includes other components through which these operating fluids flow.

[0006] In addition to supplying the operating media to the fuel cell stack, a component must also ensure the removal of the operating media after it has flowed through the fuel cells. It is known from the prior art to connect all supply and discharge lines of operating media to the fuel cell stack via a so-called "media supply unit" (MSU). The MSU functions solely as an adapter for different lines and as a media distributor. The MSU is often plate-like and is attached to one of the end plates of the fuel cell stack. The MSU is therefore also referred to as a "media adapter plate." The MSU often has a relatively simple component structure, with several short, separate channels extending between different sides of the component. PP34505WO / bg 15.10.2025 AVL List GmbH

[0007] In addition to supplying the operating fluids to and from the fuel cell stack, these fluids must also be provided in a defined state. To ensure that operating fluids are supplied in a defined quantity, at a defined temperature, and at a defined pressure, a fuel cell system therefore incorporates further components. For example, it is known from the prior art to first compress the air for supplying the cathode with oxygen in a compressor and then immediately adjust it to a defined temperature in a heat exchanger, which is supplied with a coolant via its own pump.

[0008] This architecture, often used in the prior art for fuel cell systems, has the disadvantage of requiring a relatively large number of components, each utilizing the same operating medium but needing its own control and resource supply. This becomes clear when considering the aforementioned heat exchanger for compressed air. In such a fuel cell system, the compressed air is first routed through the heat exchanger and then through the MSU (Modular Storage Unit) to the cathode. For this purpose, in addition to the fuel cell's coolant circuit, a further parallel coolant circuit is required for the heat exchanger. This increases the coolant demand, the required piping, and the energy needed to circulate the coolant. It also results in an increase in weight and installation space.

[0009] The object of the invention is to at least partially overcome the disadvantages described above. In particular, the object of the invention is to provide a device for distributing and guiding operating media that reduces the complexity, space requirements, and weight of fuel cell systems and increases their efficiency.

[0010] The foregoing problem is solved by an operating media supply unit with the features of claim 1, a fuel cell system with the features of claim 13 and a method with the features of claim 16.

[0011] Further advantages and features of the invention will become apparent from the dependent claims, the description, and the drawings. Features and details described in connection with the operating media supply unit according to the invention also apply, of course, to PP34505WO / bg 15.10.2025 AVL List GmbH

[0012] In connection with the fuel cell system according to the invention and with the method according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, mutual reference is always made or can be made.

[0013] One aspect of the invention relates to a utilities supply unit for a fuel cell stack. The utilities supply unit comprises utilities lines, each extending with a line section between a stack connection and an external connection. The utilities lines include utilities discharge lines to discharge fluids from the fuel cells of the fuel cell stack from the respective stack connection to the respective external connection. The utilities lines also include utilities supply lines to supply fluids from the respective external connection to the respective stack connection to the fuel cells. The utilities supply lines include at least one coolant supply line and one cathode supply gas supply line.The coolant supply line and the cathode supply gas supply line are heat-transferringly coupled to each other via a heat transfer section in order to change the temperature of a cathode supply gas, which is supplied to the stack connection in the cathode supply gas supply line as one of the operating media, wherein the line section of the coolant supply line has a cross-sectional profile whose cross-sectional area decreases with increasing proximity to the stack connection with respect to the cross-sectional area at the outer connection.

[0014] In other words, the invention provides an operating media supply unit for a fuel cell stack.

[0015] In this context, a self-contained device for guiding and directing fluid operating media can be understood as an operating media supply unit. The operating media supply unit can, for example, be an MSU (Mechanical Supply Unit). Furthermore, the operating media supply unit can preferably be understood as a single, functionally self-contained component that can fulfill its intended function independently of other components. PP34505WO / bg 15.10.2025 AVL List GmbH

[0016] The operating media supply unit has operating media lines with a stack connection and an external connection.

[0017] The "stack connection" and the "external connection" can each be understood as an inlet or outlet facing either towards or away from the fuel cell stack. Preferably, both connections are capable of being coupled to inlets or outlets of other fluid systems.

[0018] For example, the connections can be a free pipe end with a coupling element, such as a pipe coupling or a threaded section. The "operating fluid lines" can be understood, in particular, as fluid connections between the stack connection and the external connection. For example, an operating fluid line can be a hose, pipe, slot, or groove.

[0019] The operating media lines include operating media discharge lines and operating media supply lines to supply fluid operating media to or from the fuel cells of the fuel cell stack.

[0020] The term "operating medium discharge lines" refers specifically to lines that carry the operating media away from the fuel cells. Conversely, "operating medium supply lines" refers specifically to lines that carry the operating media to the fuel cells. "Operating medium" can be understood as any fluid necessary for the operation of the fuel cells. For example, the operating medium can be a process gas, a reaction product, and / or a coolant. For instance, the operating medium can be an anode supply gas, such as hydrogen or another fuel or fuel mixture. The operating medium can also be a cathode supply gas, such as oxygen or air, that is supplied to the cathode. The coolant can be, for example, water or a water-glycol mixture.

[0021] The operating media supply lines have at least one coolant supply line and one cathode supply gas supply line, which are coupled to each other via a heat transfer section to change the temperature of a cathode supply gas that is supplied to the stack connection in the cathode supply gas supply line as one of the operating media. PP34505WO / bg 15.10.2025 AVL List GmbH

[0022] The "coolant supply line" and the "cathode supply gas supply line" can be understood, in particular, as lines suitable for conveying the respective operating media towards the fuel cells during operation of the fuel cell stack. A "heat transfer coupling" can be understood, in particular, as a structure for conductive and / or convective heat transfer between the coupling components.

[0023] With the heat-transfer coupling according to the invention between the coolant supply line and the cathode supply gas supply line, heat from the cathode supply gas can be transferred to the coolant during operation of the fuel cell stack. This allows the functionality of a coolant-flowing heat exchanger for the cathode supply gas to be integrated into the operating media supply unit. Unlike in the prior art, this makes it possible to dispense with the heat exchanger of the fuel cell system, which is usually located directly after the compressor. A further advantage is that no separate heat exchanger needs to be installed in the operating media supply unit; instead, the required heat exchange can be achieved simply by routing the two supply lines that are needed anyway.This allows for savings in installation space, weight and resources, and increases the efficiency of the fuel cell system.

[0024] Additionally, it becomes possible to shift the location and timing of heat transfer between the cathode supply gas and the coolant closer to the point immediately before the operating fluids enter the fuel cell stack. This reduces temperature fluctuations upon entry into the fuel cell stack and stabilizes process temperatures. In addition to the aforementioned advantages, this also results in process-related benefits.

[0025] To improve conductive heat transfer, it is conceivable that the heat transfer section could extend along at least one section of each of the coolant supply line and the cathode gas supply line. Alternatively, the heat transfer section could also extend essentially the entire length of both line sections. PP34505WO / bg 15.10.2025 AVL List GmbH

[0026] To improve conductive heat transfer, it is also conceivable that the heat transfer section could extend, at least in sections, as a heat-conducting element between the coolant supply line and the cathode supply gas line, and be connected to the respective line sections. The heat-conducting element could have a heat-conducting structure, such as a fin, or a thermal paste.

[0027] To improve conductive heat transfer and simplify manufacturing, it is conceivable that the heat transfer section could extend, at least partially, as a common wall section of the coolant supply line and the cathode gas supply line. Alternatively or additionally, the heat transfer section could extend, at least partially, as contact surfaces between the coolant supply line and the cathode gas supply line, via which the line sections are in thermally conductive contact with each other.

[0028] To improve the amount of heat that can be transferred due to shared pathways, it can be advantageous if the coolant supply line and the cathode supply gas supply line extend at least partially parallel or essentially parallel to each other within the operating media supply unit.

[0029] To further improve the transferable heat quantity by lengthening the pipe sections, it can also be advantageous if the pipe section of the coolant supply line and / or the cathode supply gas supply line has a meandering, multi-curved, planar extension, at least in some sections. Alternatively or additionally, at least one of the aforementioned pipe sections can extend in a straight line, at least in some sections.

[0030] To simplify manufacturing and improve heat transfer, it can be advantageous if the sections of the coolant supply line and the cathode supply gas supply line run directly adjacent to each other, at least in sections. PP34505WO / bg 15.10.2025 AVL List GmbH

[0031] Furthermore, it can be advantageous if the section of the coolant supply line and / or the cathode gas supply line has an annular, circular, or rectangular cross-sectional profile. The cross-sectional profile can have a constant or variable diameter along the length of the pipe section, at least in certain sections.

[0032] To control heat dissipation, for example to ensure a constant heat transfer between the operating media carried in the two pipe sections, the coolant supply pipe section is designed with a cross-sectional profile whose cross-sectional area decreases with increasing proximity to the stack connection relative to the cross-sectional area at the outer connection. It can be advantageous if the cathode gas supply pipe further has a cross-sectional profile whose cross-sectional area increases with increasing proximity to the stack connection relative to the cross-sectional area at the outer connection, wherein, in particular, the coolant supply pipe section and / or the cathode gas supply pipe section extends with an annular, circular, or rectangular cross-sectional profile.

[0033] To increase the thermal efficiency of heat transfer, it can be advantageous if the sections of the cathode supply gas line and the coolant supply line each extend in opposite directions from their respective external connections towards their respective stack connections, at least in one section, in order to guide the respective operating media in opposite directions, at least in these sections. At least these sections can be heat-coupled via the heat transfer section. Besides this counter-current flow of the two operating media, it is of course also conceivable to guide them in parallel flow.

[0034] For improved assembly and mounting of the operating fluid supply unit on a fuel cell stack, it can be advantageous if the operating fluid supply unit also has a housing that encloses the operating fluid lines. Preferably, the housing can form one side of the stack and several sides different from the housing. PP34505WO / bg 15.10.2025 AVL List GmbH

[0035] The housing has outer surfaces, wherein the stack connections can each be arranged on the housing stack side and the outer connections can each be arranged on the housing outer surfaces. Furthermore, preferably, the outer connection of the cathode supply gas supply line and the outer connection of the coolant supply line can be arranged on different housing outer surfaces.

[0036] A "housing stacking side" can be understood to be, in particular, a side of the housing that rests against the fuel cell stack in the assembled state. For example, the housing stacking side can be an end face of the housing. Correspondingly, "housing outer sides" can be understood to be sides of the housing that are not the housing stacking side. For example, a side of the housing opposite the housing stacking side can be a housing outer side. Preferably, the housing can have a cuboid or plate-like shape with six sides.

[0037] To provide the operating media supply unit, to which a variety of operating media can be connected collectively, the operating media supply unit can be configured as follows. The operating media supply unit can include an anode supply gas line extending between an external anode supply gas connection and an anode supply gas stack connection. Furthermore, the operating media supply unit can include a cathode supply gas line extending between an external cathode supply gas connection and a cathode supply gas stack connection. Additionally, the operating media supply unit can include a coolant supply line extending between an external coolant supply connection and a coolant supply stack connection.Furthermore, the operating media supply unit can have an anode exhaust line extending between an anode exhaust stack connection and an anode exhaust external connection. The operating media supply unit can also have a cathode exhaust line extending between a cathode exhaust stack connection and a cathode exhaust external connection. The operating media supply unit can also have a coolant discharge line extending between a coolant discharge stack connection and a coolant discharge external connection.

[0038] Another aspect of the invention relates to a fuel cell system with at least one fuel cell stack. The fuel cell stack comprises an anode section with an anode supply section for supplying anode supply gas and an anode discharge section for removing anode exhaust gas. The fuel cell stack further comprises a cathode section with a cathode supply section for supplying cathode supply gas and a cathode discharge section for removing cathode exhaust gas. The fuel cell stack also includes a cooling section for cooling the fuel cell stack, comprising a coolant supply section for supplying coolant and a coolant discharge section for removing coolant. The fuel cell system further comprises the previously described operating media supply unit, which is fluidly and mechanically connected to the fuel cell stack.

[0039] A "fuel cell system" can be understood to mean, in particular, an arrangement of fuel cells for generating electricity. A fuel cell stack can, in particular, comprise a plurality of fuel cells arranged in a row along a stacking direction. Preferably, the fuel cell stack can have an end plate at each of its stack ends.

[0040] The fuel cell system according to the invention offers the same advantages as those explained in detail for the operating media supply unit according to the invention. In particular, it is possible to reduce the weight and system complexity of the fuel cell system while simultaneously increasing its efficiency. Furthermore, improved process control can be achieved.

[0041] The fuel cells of the fuel cell stack can be designed as PEM fuel cells or as solid oxide fuel cells.

[0042] According to a preferred embodiment, the operating media supply unit can have an anode supply gas supply line that is located between an anode supply gas external connection and a PP34505WO / bg 15.10.2025 AVL List GmbH

[0043] The operating media supply unit extends between an anode supply gas stack connection. Furthermore, the operating media supply unit may have a cathode supply gas supply line extending between a cathode supply gas external connection and a cathode supply gas stack connection. The operating media supply unit may also have a coolant supply line extending between a coolant supply external connection and a coolant supply stack connection. Additionally, the operating media supply unit may have an anode exhaust gas discharge line extending between an anode exhaust gas stack connection and an anode exhaust external connection. The operating media supply unit may also have a cathode exhaust gas discharge line extending between a cathode exhaust gas stack connection and a cathode exhaust external connection.The operating media supply unit may also have a coolant drain line that extends between a coolant drain stack connection and a coolant drain external connection.

[0044] In the fuel cell system, the anode supply gas line can connect the anode supply gas external port to the anode supply section via the anode supply gas stack port, thus providing fluid communication for the fuel cells of the fuel cell stack with anode supply gas from an anode supply gas supply. Furthermore, the cathode supply gas line can connect the cathode supply gas external port to the cathode supply section via the cathode supply gas stack port, thus providing fluid communication for the fuel cells of the fuel cell stack with cathode supply gas from a cathode supply gas supply. Additionally, the coolant supply line can connect the coolant supply external port to the coolant supply section via the coolant supply stack port, thus providing fluid communication for the cooling section with coolant from a coolant supply.The anode exhaust line can also connect the anode exhaust external connection to the anode exhaust section via the anode exhaust stack connection for fluid communication, enabling the disposal of anode exhaust from the fuel cells. Additionally, the cathode exhaust line can connect the cathode exhaust external connection to the cathode exhaust section via the cathode exhaust stack connection (PP34505WO / bg 15.10.2025 AVL List GmbH) for the disposal of cathode exhaust from the fuel cells. The coolant discharge line can also connect the coolant discharge external connection to the coolant discharge section via the coolant discharge stack connection for the disposal of coolant from the cooling section.

[0045] The term "disposal" can refer in particular to the removal or diversion of fluid from the fuel cells. A "fluid-communicating connection" can refer in particular to a connection through which a fluid can be transported to the respective connection partners.

[0046] To simplify the installation of the operating fluid supply unit on the fuel cell stack, the fuel cell stack can have operating fluid connections on one stack connection side for supplying and discharging operating fluids from the fuel cells of the fuel cell stack. The operating fluid supply unit can be arranged with the stack connections on the stack connection side and connected to the operating fluid connections in a fluid-tight manner.

[0047] Another aspect of the invention relates to a method for supplying cathode gas at a defined temperature to a cathode supply section of a fuel cell stack. The fuel cell system and operating media described above are supplied at the respective external connections. Specifically, a coolant for cooling the fuel cell stack is supplied, which has a defined external connection temperature upon entering the corresponding external connection. Furthermore, a cathode gas, in particular air, is supplied, which has a defined external connection temperature upon entering the corresponding external connection.The two operating media are simultaneously fed through the respective operating media supply lines to the respective stack connections in order to change the temperature of the cathode supply gas to a stack inlet temperature by heat transfer from the coolant.

[0048] The method according to the invention offers the same advantages as those explained in detail for the operating media supply unit and the fuel cell system according to the invention (PP34505WO / bg 15.10.2025 AVL List GmbH). In particular, it can be achieved that the temperature of the cathode supply gas is reliably and consistently changed throughout the operating period upon entering the fuel cell stack.

[0049] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The drawings schematically show:

[0050] Fig. 1 Embodiments of an operating media supply unit and a fuel cell system according to the invention,

[0051] Fig. 2 shows another embodiment of a fuel cell system according to the invention,

[0052] Figs. 3A, 3C-3E show various cross-sectional views of the coolant supply line and the cathode supply gas supply line of different embodiments of the operating media supply unit according to the invention.

[0053] Figs. 3B shows a longitudinal section view of the coolant supply line and the cathode supply gas supply line of an embodiment of the operating media supply unit according to the invention, and

[0054] Figs. 4 Line routing profiles of the coolant supply line and the cathode supply gas supply line of different embodiments of the operating media supply unit according to the invention.

[0055] The figures each show different views and aspects of the present invention.

[0056] The invention relates to a fuel supply unit 100 for a fuel cell stack 300 stacked in a stacking direction 301, and to a fuel cell system 400. Figures 1 and 2 each show examples of the structure of the fuel supply unit 100. In Figures 1 and 2, the fuel supply unit 100 performs the function of a fuel supply unit (FSU) by means of which fuel cells 360 of the fuel cell stack 300 are supplied with fuel media. The fuel supply unit 100 also discharges the fuel media after it has passed through the fuel cells 360. The fuel supply unit 100 can be connected to any fuel cell stack 300, such as stacks of PEM fuel cells or solid oxide fuel cells.Optionally, the operating media supply unit 100 can be connected directly to the fuel cell stack 300 (Figure 1) or to one of the end plates 370 of the fuel cell stack 300 (Figure 2).

[0057] Typical operating media for the Fuel Cell Stack 300 are air as the gas supplied to the cathode, hydrogen as the gas supplied to the anode, and a coolant such as water, which allows the waste heat generated during power generation to be dissipated from the Fuel Cell Stack 300. Substances produced in the Fuel Cell Stack 360, such as water, can also serve as an operating medium.

[0058] For conveying the operating media to and from the fuel cell stack 300, the operating media supply unit 100 has several operating media lines, each extending within the operating media supply unit 100 with a line section between a stack connection 150 and an external connection 140. The stack connections 150 are preferably provided for connection to the line inlets and outlets of the fuel cell stack 300. For this purpose, the fuel cell stack 300 can have a series of operating media connections on a stack connection side SAS for supplying and removing operating media from the fuel cells 360, as illustrated by way of example in Figure 1. The operating media supply unit 100 can preferably be arranged with the stack connections 150 on the stack connection side SAS.The stack connections 150 can, for example, have couplings or threads to ensure a quick and reliable connection to the operating media connections of the fuel cell stack 300. The external connections 140, on the other hand, are preferably intended for connection to line inlets and outlets of external devices of the fuel cell system 400. PP34505WO / bg 15.10.2025 AVL List GmbH.

[0059] Figures 1 and 2 illustrate the typical orientation and operating position intended for operation. The typical flow directions of the operating media in the operating media lines are also indicated in these figures. For the sake of clarity, these flow directions are also used in Figure 4.

[0060] For the supply of fluid operating media during the operation of the fuel cell stack 300, several operating media supply lines 111, 112, 113 are provided in the operating media supply unit 100. A fluid flow is typically directed through these supply lines 111, 112, 113 towards the fuel cell stack 300, which corresponds to a flow direction of the operating medium from an external connection 140 to a stack connection 150.

[0061] The operating media supply unit 100 in Figures 1 and 2, for example, has a cathode supply gas supply line 111, an anode supply gas supply line 112 and a coolant supply line 113.

[0062] The anode supply gas line 112 can extend between an anode supply gas external connection 145 and an anode supply gas stack connection 155. During operation of the fuel cell stack 300, an anode supply gas AZG, such as hydrogen or a hydrogen-containing fuel, can be supplied via the anode supply gas line 112 to an anode supply section 321 of an anode section 320 of the fuel cell stack 300. For this purpose, a fluid-communicating and preferably gas-tight connection can be provided between the anode supply section 321 and the anode supply gas line 112. The anode supply gas AZG can be provided by an anode supply gas supply 420. The anode supply gas supply 420 can, for example, be a storage device or a reformer.

[0063] The cathode supply gas line 111 can extend between a cathode supply gas external connection 142 and a cathode supply gas stack connection 152. During operation of the fuel cell stack 300, a cathode supply gas (CSP) can be supplied via the cathode supply gas line 111, as per PP34505WO / bg 15.10.2025 AVL List GmbH

[0064] Air is supplied to a cathode supply section 311 of a cathode section 310 of the fuel cell stack 300. For this purpose, the cathode supply gas supply line 111 can be fluidly connected and preferably gas-tight to the cathode supply section 311. The cathode supply gas (CSP) can be provided by a cathode supply gas supply 410, which can be designed, for example, as a hot air blower and / or compressor.

[0065] The coolant supply line 113 is required to provide a coolant KME for cooling a cooling section 330 of the fuel cell stack 300. The cooling section 330 can, for example, be formed by cooling channels in the fuel cells 360 of the fuel cell stack 300. The coolant supply line 113 extends between a coolant supply external connection 143 and a coolant supply stack connection 153. During operation, the coolant KME can be conveyed via the coolant supply line 113 to a coolant supply section 331 of the cooling section 330. For this purpose, the coolant supply line 113 can be fluidly connected to the coolant supply section 331 and preferably gas-tight. The incoming coolant KME can be supplied by a coolant supply 430, such as a water tank.

[0066] For the discharge of fluid operating media during the operation of the fuel cell stack 300, operating media discharge lines 121, 122, 123 are also provided. These discharge lines 121, 122, 123 thus typically direct a fluid flow away from the fuel cell stack 300 in one direction. Such flow directions correspond, for example, to a direction from a stack connection 150 to an associated external connection 140.

[0067] For the purpose of discharging the operating media, the operating media supply unit 100 in Figures 1 and 2, for example, has a cathode exhaust gas discharge line 121, an anode exhaust gas discharge line 122 and a coolant discharge line 123.

[0068] The anode exhaust gas discharge line 122 can extend between an anode exhaust gas stack connection 156 and an anode exhaust gas external connection 146. During operation, for example, anode exhaust gas, such as water, can be discharged from the fuel cells 360 via an anode discharge section 322 through the anode exhaust gas discharge line 122. The anode exhaust gas discharge line 122 can be connected to the anode discharge section in a fluid-communicating and preferably gas-tight manner.

[0069] 322 connected.

[0070] The cathode exhaust gas discharge line 121 can extend between a cathode exhaust gas stack connection 151 and a cathode exhaust gas external connection 141. During operation, for example, cathode exhaust gas (CEG), such as water, can be discharged via the cathode exhaust gas discharge line 121 through a cathode discharge section 312 of the cathode section 310. For this purpose, the cathode exhaust gas discharge line 121 can be connected to the cathode discharge section 312 in a fluid-communicating and preferably gas-tight manner.

[0071] To discharge the coolant from the cooling section 330, the coolant discharge line 123 is shown in Figures 1 and 2. This line can extend between a coolant discharge stacking connection 154 and a coolant discharge external connection 144. The coolant discharge line 123 can also be connected to a coolant discharge section 332 of the cooling section 330 in a fluid-communicating and preferably gas-tight manner.

[0072] Preferably, all operating media lines can be arranged within a housing 190 (see Figures 1 and 2). The housing 190 can have a housing stack side GSS and several housing outer sides GAS different from the housing stack side GSS. The stack connections 150 can preferably all be arranged on the housing stack side GSS to facilitate connection to the fuel cell stack 300. The outer connections 140, on the other hand, can all be arranged on the housing outer sides GAS. Preferably, by a clever arrangement of the outer connections 142, 143 of the cathode supply gas supply line 111 and the coolant supply line 113 on different housing outer sides GAS, advantageous flow routing as well as shortening or lengthening of line lengths can be achieved, which can promote heat exchange.

[0073] In the operating media supply unit 100, the coolant supply line 113 and the cathode supply gas supply line 111 are also coupled to each other via a heat transfer section 130 to change the temperature of the cathode supply gas KZG. Figures 1, 3 and 4 PP34505WO / bg 15.10.2025 AVL List GmbH show different examples of heat transfer coupling using the heat transfer section 130.

[0074] In Figure 1, the heat transfer section 130 is shown schematically as a heat-conducting element, such as a fin. Such a heat-conducting element can extend between the coolant supply line 113 and the cathode supply gas supply line 111, transversely to the direction of extension of the coolant supply line 113 and the cathode supply gas supply line 111. The heat transfer section 130 can also extend completely along these line sections, as also shown in Figure 1. Figure 3E shows a similar, further example in which the heat transfer section 130 is shown as a solid, thermally conductive material between the two supply lines 111 and 113.

[0075] Figures 3A to 3D show further examples of the heat transfer section 130. Figures 3A, 3C, and 3D show, for example, that the heat transfer section 130 can extend, at least partially, as a common wall section of the coolant supply line 113 and the cathode supply gas supply line 111. In Figure 3C, the heat transfer section 130 is formed from the same material as the supply lines 111 and 113. In Figure 3A, the heat transfer section 130 is formed by one of the supply lines 111 and 113 itself. In Figure 3D, the heat transfer section 130 has a different material, e.g., copper, than the walls enclosing the supply lines 111 and 113, such as a plastic material. Additionally, Figure 3D shows that the feed lines 111, 113 can preferably be formed as grooves in two complementary housing parts 191, 192 of the housing 190.

[0076] Figure 3E further shows an example similar to Figure 3C. However, in Figure 3B, the coolant supply line 113 and the cathode supply gas supply line 111 are pressed together, so that the heat transfer section 130 extends at least partially as contact surfaces of the two supply lines 111, 113, thus establishing a thermally conductive contact. Preferably, a thermal paste can also be provided between the two supply lines 111, 113. PP34505WO / bg 15.10.2025 AVL List GmbH

[0077] Figure 3B further shows an example where the coolant supply line 113 and the cathode gas supply line 111 can extend with an annular cross-sectional profile, which can have a variable diameter D along the length of the line section. Figure 3B illustrates by way of example that the cross-sectional area of ​​the coolant supply line 113 can decrease towards the stack connection 150, while the cross-sectional area of ​​the cathode gas supply line 111 can increase in the opposite direction towards the stack connection 150. This allows, for example, the cooling capacity to be kept constant along the length of the line.

[0078] Figures 4A to 4D show different pipe routing profiles for the coolant supply line 113 and the cathode supply gas supply line 111.

[0079] In Figure 4A, the cathode supply gas line 111 is designed, for example, as a cooling chamber, which is covered by the meandering coolant supply line 113 as a cooling coil. The heat transfer section 130 can be designed as a common wall section (for example, in the case of a cooling coil immersed in the cooling chamber) or as a standing contact surface.

[0080] Figure 4D shows a counterflow configuration of the cathode supply gas line 111 and the coolant supply line 113. In this configuration, each line section has subsections where the flow directions are opposite to each other. The heat transfer section 130 can be configured as a common wall section (as in Figures 3C or 3D) or as a heat-conducting element (as in Figure 3E).

[0081] In Figure 4B, the section of the cathode supply gas line 111 extends in a straight line. In contrast, the section of the coolant supply line 113 has a meandering, multi-curved, planar extension as well as a straight extension, from which a bypass line section 1133 is formed in Figure 4B. The bypass line section 1133 and the meandering section of the coolant supply line 113 are connected to each other via a branch point 1131 and a connection point 1132. At least one of the branch point 1131 and connection point 1132 can have a control valve, which can be controlled by a control unit 500. PP34505WO / bg 15.10.2025 AVL List GmbH

[0082] In this way, for example, the temperature of the cathode supply gas can be regulated and switched on as needed.

[0083] In Figure 4C, the pipe sections of the cathode gas supply line 111 and the coolant supply line 113 extend in a straight line, parallel to each other, and are directly adjacent. A heat transfer section 130 between the cathode gas supply line 111 and the coolant supply line 113 can be formed by a common wall section (as in Figures 3C or 3D). Furthermore, Figure 4C shows another heat transfer section 130 extending between the cathode gas supply line 111 and the coolant discharge line 123. The cathode gas supply line 111 is covered by a bypass pipe section 1233, the coolant flow KMA of which can be controlled by control valves at a branch point 1231 and / or a connection point 1232. For this purpose, the control unit 500 can preferably be provided in the fuel cell system 400.In this way, the temperature of the cathode supply gas KZG in the cathode supply gas supply line 111 can be changed not only by the coolant KMA from the fuel cell stack 300, but also by coolant KME from the coolant supply 430. It is of course also conceivable to combine the devices from Figures 4B and 4C.

[0084] Another aspect of the invention relates to a method for supplying cathode supply gas (CSP) at a defined temperature to the cathode supply section 311 in the fuel cell system 400. Here, the coolant (CME) is supplied at the external connection 143 at a defined external connection temperature (e.g., 10 degrees Celsius). Likewise, the cathode supply gas (CSP) is supplied at the external connection 142 at a defined external connection temperature (e.g., 100 degrees Celsius). The coolant (CME) and the cathode supply gas (CSP) are then simultaneously fed through the supply lines 111 and 113 to the respective stack connections 150, and the temperature of the cathode supply gas (CSP) is thereby changed to a defined stack inlet temperature (e.g., 80 degrees Celsius) by means of heat transfer. PP34505WO / bg October 15, 2025 AVL List GmbH

[0085] Preferably, the operating media supply unit can generate 100 temperature differences between the cathode supply gas external connection temperature and the stack inlet temperature of 1 to 2 degrees Celsius, 1 to 5 degrees Celsius, 1 to 10 degrees Celsius, 1 to 20 degrees Celsius or 1 to 30 degrees Celsius.

[0086] The preceding explanation of the embodiments describes the present invention exclusively by way of examples.

[0087] In principle, it is also conceivable to couple other pairs of operating fluid lines with each other in a heat-transferring manner. For example, the coolant discharge line 123 could be heat-transferred with the cathode supply gas line instead of the coolant supply line 113, for instance, to change the temperature of the cathode supply gas. Alternatively or additionally, it would also be conceivable to heat-transfer the coolant supply line 113 with the anode supply gas line 112. It is also conceivable that, for example, more than just two of the operating fluid lines are heat-transferred with each other. In particular, three or more of the operating fluid lines can be heat-transferred with each other.

[0088] PP34505WO / bg October 15, 2025 AVL List GmbH

[0089] Reference symbol list

[0090] 100 Operating media supply unit

[0091] 111, 112, 113 Operating media supply lines

[0092] 111 Cathode supply gas supply line

[0093] 113 Coolant supply line

[0094] 121-123 Operating fluid drain lines

[0095] 121 Cathode exhaust gas discharge line

[0096] 122 Anode exhaust gas discharge line

[0097] 123 Coolant drain line

[0098] 130 Heat transfer section

[0099] 140 external connection

[0100] 141 Cathode exhaust external connection

[0101] 142 Cathode supply gas external connection

[0102] 143 Coolant supply external connection

[0103] 144 Coolant drain external connection

[0104] 145 Anode supply gas external connection

[0105] 146 Anode exhaust external connection

[0106] 150 stack connection

[0107] 151 Cathode exhaust stack connection

[0108] 152 Cathode supply gas stack connection

[0109] 153 Coolant supply stacking connection

[0110] 154 Coolant drain stack connection

[0111] 155 Anode supply gas stack connection

[0112] 156 anode exhaust stack connection

[0113] 190 cases

[0114] 191, 192 Housing part

[0115] 300 fuel cell stacks

[0116] 301 Stacking direction

[0117] 310 Cathode section

[0118] 311 Cathode feed section

[0119] 312 Cathode discharge section PP34505WO / bg 15.10.2025 AVL List GmbH

[0120] 320 anode section

[0121] 321 Anode feed section

[0122] 322 Anode discharge section

[0123] 330 Cooling section

[0124] 331 Coolant supply section

[0125] 332 Coolant discharge section

[0126] 360 Fuel Cell

[0127] 370 End plate

[0128] 400 fuel cell systems

[0129] 410 Cathode supply gas supply

[0130] 420 Anode supply gas supply

[0131] 430 Coolant supply

[0132] 500 control unit

[0133] 1131 Branch point, control valve

[0134] 1132 liaison point

[0135] 1133 Bypass line section

[0136] 1231 Branch point, control valve

[0137] 1232 liaison point

[0138] 1233 Bypass line section

[0139] AAG anode exhaust

[0140] AZG anode supply gas

[0141] GAS Housing Exterior

[0142] GSS Housing Stacking Side

[0143] KAG cathode exhaust

[0144] KMA escaping coolant

[0145] KME inflowing coolant

[0146] KZG cathode supply gas

[0147] SAS stack connector side

[0148] Diameter

Claims

PP34505WO / bg October 15, 2025 AVL List GmbH Patent claims 1. Operating media supply unit (100) for a fuel cell stack (300), comprising: - Operating media lines, each extending with a line section between a stack connection (150) and an external connection (140), comprising: o Operating media discharge lines (121, 122, 123) for discharging fluid operating media from the fuel cells (360) of the fuel cell stack (300) from the respective stack connection (150) to the respective external connection (140), and o Operating media supply lines (111, 112, 113) for supplying fluid operating media to the fuel cells (360) of the fuel cell stack (300) from the respective external connection (140) to the respective stack connection (150), wherein the operating media supply lines (111, 112, 113) comprise at least one coolant supply line (113) and one cathode supply gas supply line (111), wherein the coolant supply line (113) and the cathode supply gas supply line (111) are coupled to each other via a heat transfer section (130) for heat transfer,to change the temperature of a cathode supply gas (CSG) which is supplied to the stack connection (150) in the cathode supply gas supply line (111) as one of the operating media, characterized in that the line section of the coolant supply line (113) has a cross-sectional profile whose cross-sectional area decreases with increasing proximity to the stack connection (150) with respect to the cross-sectional area at the external connection (140).

2. Operating media supply unit (100) according to claim 1, wherein the Heat transfer section (130) each at least one Section of the coolant supply line (113) and the PP34505WO / bg October 15, 2025 AVL List GmbH cathode supply gas supply line (111) extends or substantially extends along both line sections.

3. Operating media supply unit (100) according to claim 1 or claim 2, wherein the heat transfer section (130) extends at least sectionally as a heat conducting element between the coolant supply line (113) and the cathode supply gas supply line (111) and is connected to the respective line sections, wherein the heat conducting element preferably has a heat conducting structure, such as a fin, or a thermal paste.

4. Operating media supply unit (100) according to one of the preceding claims, wherein the heat transfer section (130) extends at least section by section as a common wall section of the pipe sections of the coolant supply line (113) and the cathode supply gas supply line (111), and / or wherein the heat transfer section (130) extends at least section by section as contact surfaces of the coolant supply line (113) and the cathode supply gas supply line (111), via which the pipe sections are in thermally conductive contact with each other.

5. Operating media supply unit (100) according to one of the preceding claims, wherein the coolant supply line (113) and the cathode supply gas supply line (111) extend at least sectionally parallel or substantially parallel to each other within the operating media supply unit (100).

6. Operating media supply unit (100) according to one of the preceding claims, wherein the line section of the coolant supply line (113) and / or the cathode supply gas supply line (111) extends at least PP34505WO / bg 15.10.2025 AVL List GmbH extends in sections in a straight line and / or has a meandering, multi-wound, planar extension.

7. Operating media supply unit (100) according to one of the preceding claims, wherein the pipe sections of the coolant supply line (113) and the cathode supply gas supply line (111) extend at least sectionally directly adjacent to each other.

8. Operating media supply unit (100) according to one of the preceding claims, wherein the line section of the coolant supply line (113) and / or the cathode supply gas supply line (111) extends with an annular, circular or rectangular cross-sectional profile, wherein preferably the cross-sectional profile along the extent of the line section has a diameter (D) that is at least sectionally constant or variable.

9. Operating media supply unit (100) according to one of claims 1 to 7, wherein the line section of the coolant supply line (113) and / or the cathode supply gas supply line (111) extends with an annular, circular or rectangular cross-sectional profile.

10. Operating media supply unit (100) according to one of claims 1 to 7 or 9 wherein the cathode supply gas supply line (111 ) has a cross-sectional profile whose cross-sectional area increases with increasing proximity to the stack connection (150) with respect to the cross-sectional area at the external connection (140), wherein in particular the line section of the coolant supply line (113) and / or the cathode supply gas supply line (111 ) extends with an annular, circular or rectangular cross-sectional profile. PP34505WO / bg October 15, 2025 AVL List GmbH 11. Operating media supply unit (100) according to one of the preceding claims, wherein the line sections of the cathode supply gas supply line (111) and the coolant supply line (113) each extend in opposite directions from the respective external connection (140) towards the respective stack connection (150) at least in one line section, in order to guide the respective operating media in opposite directions at least in the line sections, wherein at least the line sections are coupled to each other via the heat transfer section (130) for heat transfer.

12. Operating media supply unit (100) according to one of the preceding claims, further comprising a housing (190) in which the operating media lines are enclosed, wherein preferably the housing (190) has a housing stacking side (GSS) and several housing outer sides (GAS) different from the housing stacking side (GSS), wherein the stacking connections (150) are arranged on the housing stacking side (GSS) and the outer connections (140) are arranged on the housing outer sides (GAS), wherein further preferably the outer connection (142) of the cathode supply gas supply line (111) and the outer connection (143) of the coolant supply line (113) are arranged on different housing outer sides (GAS).

13. Fuel cell system (400) with at least one fuel cell stack (300) of fuel cells (360), wherein the fuel cell stack (300) comprises: - an anode section (320) which has an anode supply section (321) for supplying anode supply gas (AZG) and an anode discharge section (322) for removing anode exhaust gas (AAG), - a cathode section (310) which includes a cathode supply section (311) for supplying cathode supply gas (CSP) and a PP34505WO / bg October 15, 2025 AVL List GmbH cathode discharge section (312) for the discharge of cathode exhaust gas (CAG), and - a cooling section (330) for cooling the fuel cell stack (300), which has a coolant supply section (331) for supplying coolant (KME) and a coolant discharge section (332) for removing coolant (KMA), characterized by - a utilization unit (100) according to one of the preceding claims, comprising: o an anode supply gas supply line (112) extending between an anode supply gas external connection (145) and an anode supply gas stack connection (155); o a cathode supply gas supply line (111) extending between a cathode supply gas external connection (142) and a cathode supply gas stack connection (152); o a coolant supply line (113) extending between a coolant supply external connection (143) and a coolant supply stack connection (153); o an anode exhaust gas discharge line (122) extending between an anode exhaust gas stack connection (156) and an anode exhaust gas external connection (146); o a cathode exhaust gas discharge line (121 ), which extends between a cathode exhaust stack connection (151 ) and a cathode exhaust external connection (141 ), and a coolant discharge line (123),which extends between a coolant discharge stack connection (154) and a coolant discharge external connection (144), wherein the anode supply gas supply line (112) fluidly connects the anode supply gas external connection (145) via the anode supply gas stack connection (155) to the anode supply section (321) for supplying the fuel cells (360) of the fuel cell stack (300) with anode supply gas (ASG) from an anode supply gas supply (420), 1, PP34505WO / bg 15.10.2025 AVL List GmbH wherein the cathode supply gas supply line (111) connects the cathode supply gas external connection (142) via the cathode supply gas stack connection (152) to the cathode supply section (311) in a fluid-communicating manner for supplying the fuel cells (360) of the fuel cell stack (300) with cathode supply gas (CSP) from a cathode supply gas supply (410), wherein the coolant supply line (113) connects the coolant supply external connection (143) via the coolant supply stack connection (153) to the coolant supply section (331) in a fluid-communicating manner for supplying the cooling section (330) with coolant (CSP) from a coolant supply (430), wherein the anode exhaust gas discharge line (122) The anode exhaust gas external connection (146) is connected via the anode exhaust gas stack connection (156) to the anode discharge section (322) in a fluid-communicating manner for the disposal of the anode exhaust gas (AEG) from the fuel cells (360),wherein the cathode exhaust gas discharge line (121) connects the cathode exhaust gas external connection (141) via the cathode exhaust gas stack connection (151) to the cathode discharge section (312) for the disposal of the cathode exhaust gas (CEG) from the fuel cells (360), and wherein the coolant discharge line (123) connects the coolant discharge external connection (144) via the coolant discharge stack connection (154) to the coolant discharge section (332) for the disposal of the coolant (CV) from the cooling section (330).

14. Fuel cell system (400) according to claim 13, wherein the fuel cell stack (300) has operating media connections on a stack connection side (SAS) for supplying and removing operating media from the fuel cells (360) of the fuel cell stack (300), and the operating media supply unit (100) with the stack connections (150) is arranged on the stack connection side (SAS) and is fluid-tightly connected to the operating media connections. PP34505WO / bg October 15, 2025 AVL List GmbH 15. Fuel cell system (400) according to claim 13 or claim 14, wherein the fuel cells (360) have a polymer electrolyte membrane or the fuel cells (360) are solid oxide fuel cells.

16. Method for supplying cathode supply gas (CSP) with a defined cathode supply gas temperature to a cathode supply section (311) of a fuel cell stack (300), comprising: - Providing a fuel cell system (400) according to any one of claims 13 to 15, - Provision of operating media at the respective external connections, comprising: o Provision of a coolant (KME, KMA) for cooling the fuel cell stack (300) with a defined coolant external connection temperature, and o Provision of a cathode supply gas (KZG) with a defined cathode supply gas external connection temperature, - simultaneous flow of the coolant (KME) through the coolant supply line (113) and the cathode supply gas (KZG) in the cathode supply gas supply line (111) to the respective stack connections (150) in order to change the temperature of the cathode supply gas (KZG) by heat transfer from the coolant (KME, KMA) to a stack inlet temperature.

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