Fuel cell vehicle with a tunnel

Abstract

According to the invention, a fuel cell vehicle is provided with a fuel cell to which a hydrogen tank and a cooling system are associated, and with a tunnel formed under a passenger compartment in which the hydrogen tank is located, wherein the tunnel has an inner tunnel surface and the hydrogen tank has an outer tank surface, and a free space exists between the inner tunnel surface and the outer tank surface. According to the invention, at least one cooling line of the cooling system is arranged in the free space.

Description

[0001] The invention relates to a fuel cell vehicle with a fuel cell to which a hydrogen tank and a cooling system are assigned, and with a tunnel formed under the passenger compartment in which the hydrogen tank is located, wherein the tunnel has an inner tunnel surface and the hydrogen tank has an outer tank surface and there is a free space between the inner tunnel surface and the outer tank surface.

[0002] In motor vehicles, especially passenger cars, which have a passenger compartment, there is usually a tunnel beneath the passenger compartment that extends longitudinally, or in the main direction of travel, from the front to the rear of the vehicle. The tunnel thus connects the front of the vehicle to the rear and serves to house the drivetrain and to channel exhaust gases.

[0003] Vehicles powered by gaseous energy carriers, especially hydrogen, typically have a large tank system. This is particularly true for vehicles with a fuel cell as their drive unit, where the tank system requires considerable installation space. It is common practice for such vehicles to locate the tank system, or at least parts of it, within the tunnel.

[0004] A fuel cell vehicle with a fuel cell is already known from DE 10 2009 048 573 A1. The fuel cell is associated with a hydrogen tank and a cooling system, with the hydrogen tank located below the passenger compartment.

[0005] According to the invention, a fuel cell vehicle is provided with a fuel cell to which a hydrogen tank and a cooling system are assigned, and with a tunnel formed under a passenger compartment in which the hydrogen tank is located. The tunnel has an inner tunnel surface and the hydrogen tank has an outer tank surface, and a free space exists between the inner tunnel surface and the outer tank surface. According to the invention, at least one cooling line of the cooling system is arranged in this free space. The tunnel according to the invention is particularly delimited towards the passenger compartment by a tunnel wall, which preferably has a ceiling section and two side wall sections. Furthermore, the tunnel is advantageously delimited towards the underbody of the fuel cell vehicle by a tunnel floor. The tunnel wall, orThe ceiling section and the two side wall sections and / or the tunnel floor thus form interior tunnel surfaces. The hydrogen tank according to the invention is bounded externally by a tank wall, which thus forms an exterior tank surface.

[0006] The cooling system according to the invention is, in particular, a cooling system for a fuel cell in which cooling water is heated by the fuel cell and subsequently conveyed through an air-cooled radiator (direct cooling). A further preferred cooling system involves spraying pure water into air supplied to the fuel cell (indirect cooling). The water evaporates and is then condensed from the exhaust gas of the fuel cell. This condensation preferably takes place in two stages in a high-temperature-to-high-temperature condenser or a high-temperature-to-low-temperature condenser.

[0007] Alternatively, a compression cooling system is used. In such a cooling system, a gaseous refrigerant or cooling medium is compressed by a compressor, particularly adiabatically (without heat exchange with the environment), which causes the refrigerant to heat up. The thermal energy of the gaseous, compressed refrigerant is released to the environment by means of a condenser, causing the refrigerant to condense. The refrigerant then flows through a throttle to reduce its pressure and then into an evaporator. The evaporator is located in or on the space or component to be cooled. There, the evaporating refrigerant absorbs the necessary heat of vaporization (evaporative cooling) and flows back to the compressor as a gas. In such a cooling system, the cooling lines according to the invention are used to transport the gaseous, pressurized refrigerant and / or the liquid refrigerant.

[0008] The outer surface of the tank is rounded, and the inner surface of the tunnel is at least partially angled. The cooling line according to the invention is arranged in the space between the rounded tank surface and the angled tunnel surface. The cooling line is specifically adapted to the cross-sectional shape of the surrounding components, in this case the tank and tunnel. This design makes particularly advantageous use of the free or empty installation space that would otherwise result from the technically most sensible construction of the associated vehicle body and hydrogen tank.

[0009] The cooling line according to the invention particularly preferably forms a section of a high-temperature circuit of the cooling system. The high-temperature circuit is a circuit or section of the cooling system in which components with a temperature above approximately 60 °C are cooled. Such components are, in particular, a charge air cooler of the fuel cell, the fuel cell itself, or a condenser of an indirect cooling system. Advantageously, the fuel cell is installed in the rear of the fuel cell vehicle. Furthermore, at least one radiator of the cooling system is advantageously installed in the front of the fuel cell vehicle.

[0010] Alternatively, according to the invention, the cooling line forms a section of a low-temperature circuit of the cooling system. The low-temperature circuit is a circuit or section of the cooling system in which components with a temperature below approximately 60 °C are cooled. Such components are, in particular, electronic components, a high-voltage storage device, or a condenser for indirect cooling. The fuel cell is preferably installed in the front section of the fuel cell vehicle. Furthermore, it is advantageous to install at least one radiator of the cooling system in the rear section of the fuel cell vehicle.

[0011] In the cooling system according to the invention, at least one further component of the motor vehicle to be cooled is also advantageously arranged. Such a component is, in particular, a charge air cooler of the fuel cell.

[0012] Furthermore, according to the invention, two or more cooling lines of the cooling system are preferably formed in a corresponding free space between the tunnel surface and the tank surface.

[0013] With the solution according to the invention and its further developments, it is possible to transfer a cooling medium, in particular a coolant, from the front of the vehicle to the rear of the vehicle, where it can be used to cool the fuel cell and other components. This is particularly advantageous because it allows both the front and rear of the vehicle to be used for cooling functions. This is advantageous with regard to the total external surface area available on the vehicle and the available installation space.

[0014] The inventive, targeted routing of one or more cooling lines through a free space in the tunnel can be advantageously used to connect two or more cooling components of a fuel cell system. In particular, it is advantageous to route coolant from a cooler to a fuel cell.

[0015] The solution according to the invention allows coolant to be conveyed and returned from a front radiator to the rear of the associated vehicle with particular advantage. This is especially beneficial with regard to cooling a fuel cell located in the rear of the vehicle.

[0016] Exemplary embodiments of the solution according to the invention are explained in more detail below with reference to the accompanying schematic drawings. These show: Fig. 1 a side view of a first embodiment of a fuel cell motor vehicle according to the invention, Fig. 2 the top view II according to Fig. 1, Fig. 3 the section III - III according to Fig. 2 and Fig. 4 the top view according to Fig. 2 of a second embodiment of a fuel cell motor vehicle according to the invention.

[0017] The figures show a fuel cell vehicle 10 designed as a passenger car (PKW) and having a front section 12 with two front wheels 14, a passenger compartment 16 arranged behind it in relation to the longitudinal axis of the vehicle and a rear section 18 arranged behind it with two rear wheels 20.

[0018] On the front section 12 there is a front inlet 22 for outside air, which can be directed through a front radiator 26 located behind it by means of a front fan 24.

[0019] In the embodiment according to Fig. In the rear section 18, a fuel cell 28 is located as part of a drive unit for the fuel cell vehicle 10. The fuel cell 28 and the front radiator 26 are integrated into a cooling system 30, which forms a high-temperature circuit and serves in particular for the direct cooling of the fuel cell 28. For this purpose, two cooling lines 32 are provided as part of the cooling system 30, by means of which a coolant (not shown) can be transported from the front radiator 26 to the fuel cell 28 and back. The cooling lines 32 are routed from the front section 12 to the rear section 18 and back.

[0020] A tunnel 34 is located centrally beneath the passenger compartment 16, extending along its entire length. This tunnel is separated from the passenger compartment 16 by a tunnel wall 36 and from below by a tunnel floor 38, thus largely closing it off. The tunnel wall 36 and the tunnel floor 38 form an interior tunnel surface, which is angled, particularly at the transition between the tunnel wall 36 and the tunnel floor 38. An elongated hydrogen tank 40, which supplies hydrogen as fuel for the fuel cell 28, is located within the tunnel 34. The hydrogen tank 40 is separated from the tunnel 34 by a tank wall 42, which is cylindrical or rounded. A space 44 is located between this tank wall 42 and the tunnel wall 36 or the tunnel floor 38. This space is specifically used as installation space for the cooling lines 32.

[0021] For pumping the cooling medium in the cooling lines 32, the cooling system 30 designed in this way also includes a coolant pump 46, an optional second coolant pump 48, an ion exchanger 50, and an expansion tank 52. These components 46, 48, 50, and 52 can also advantageously be arranged in the free space 44 or a part thereof.

[0022] Furthermore, an additional component 54 to be cooled, such as in particular a charge air cooler, can advantageously be arranged in the cooling system 30.

[0023] In Fig. Figure 4 illustrates an embodiment of a fuel cell vehicle 10 in which the fuel cell 28 is arranged in a high-temperature circuit of a cooling system 30 in the front section 12, and an electric machine or electric motor 56 is located at the rear end of the tunnel 34, relative to the main direction of travel. This electric motor 56 is integrated into a low-temperature circuit of the cooling system 30. As in the embodiment according to Fig. 1 to 3 two cooling lines 32 through associated free spaces 44 in the tunnel 34 from front to back and back to the front.

[0024] In the rear section 18 of this embodiment there are also two rear radiators 58 and a coolant pump 46, which are also integrated into the low-temperature circuit of the cooling system 30.

[0025] In the front section 12 of the associated motor vehicle 10, an ion exchanger 50 and an expansion tank 52 are also integrated into the high-temperature circuit of the cooling system 30.

[0026] In the low-temperature circuit, further components 54 to be cooled are also arranged in the front section 12, namely a DC and / or AC converter for a compressor, as well as an optional coolant pump 48.

[0027] In the high-temperature circuit of the cooling system 30 according to Fig. In addition, a front radiator 26, a coolant pump 46, an ion exchanger 50, and an expansion tank 52 are integrated into the front section 12. Further components 54 requiring cooling can also be connected to this high-temperature circuit.

Claims

[1] Fuel cell motor vehicle (10) with a fuel cell (28) to which a hydrogen tank (40) and a cooling system (30) are assigned, and with a tunnel (34) formed under a passenger compartment (16) in which the hydrogen tank (40) is located, wherein the tunnel (34) has an inside tunnel surface (36, 38) and the hydrogen tank (40) has an outside tank surface (42) and there is a free space (44) between the inside tunnel surface (36, 38) and the outside tank surface (42), wherein at least one cooling line (32) of the cooling system (30) is arranged in the free space (44), characterized by that the outer tank surface (42) is rounded and the inner tunnel surface (36, 38) is angled and the cooling line (32) is arranged in the free space (44) between the rounded tank surface (42) and the angled tunnel surface (36, 38). [2] Fuel cell motor vehicle according to claim 1, wherein the cooling line (32) forms a portion of a high-temperature circuit of the cooling system (30). [3] Fuel cell motor vehicle according to claim 2, wherein the fuel cell (28) is installed in the rear carriage (18) of the fuel cell motor vehicle (10). [4] Fuel cell motor vehicle according to claim 2 or 3, wherein at least one cooler (26) of the cooling system (30) is installed in the front end (12) of the fuel cell motor vehicle (10). [5] Fuel cell motor vehicle according to claim 1, wherein the cooling line (32) forms a portion of a low-temperature circuit of the cooling system (30). [6] Fuel cell motor vehicle according to claim 4, wherein the fuel cell (28) is installed in the front end (12) of the fuel cell motor vehicle (10). [7] Fuel cell motor vehicle according to claim 5 or 6, wherein at least one cooler (58) of the cooling system (30) is installed in the rear section (18) of the fuel cell motor vehicle (10). [8] Fuel cell motor vehicle according to one of claims 1 to 7, wherein at least one further component (54) of the motor vehicle (10) to be cooled is arranged in the cooling system (30). [9] Fuel cell motor vehicle according to one of claims 1 to 8, wherein at least two cooling lines (32) of the cooling system (30) are each formed in an associated free space (44) between the tunnel surface (36, 38) and the tank surface (42).

Images