WO2021004714A1

WO2021004714A1 - Water tank system for providing water for a vehicle which is operated with fuel cells

Info

Publication number: WO2021004714A1
Application number: PCT/EP2020/065812
Authority: WO
Inventors: Michael Giuseppe MARINO; Jochen Braun; Ralph Leonard FUNG
Original assignee: Robert Bosch Gmbh
Priority date: 2019-07-05
Filing date: 2020-06-08
Publication date: 2021-01-14
Also published as: JP2022537837A; JP7350900B2; DE102019209932A1; EP3994754A1; CN114365314A

Abstract

The invention relates to a water tank system (100) for a vehicle which is operated with fuel cells. The water tank system has a water separator (104) which is designed to separate water from steam, comprising a feed line (106) for receiving steam from a fuel cell stack and a discharge line (110) for dispensing the separated water. The water tank system (100) additionally has a water tank (102) which is designed to store the water from the water separator (104) and a filling opening (110) which is designed for filling the water tank (102) with the separated water and which is connected to the discharge line of the water separator (104). The water tank system also has a removal device (108) for removing water from the water tank (102).

Description

description

Water tank system for providing water for a vehicle operated with fuel cells

Technical area

The invention relates to a water tank system for providing water for a vehicle operated with fuel cells, a vehicle having such a water tank system, and a method for providing water through such a water tank system.

State of the art

In fuel cells, an electrolyte separates the electrons from the hydrogen atoms at the anode. The electrons are led to the cathode through a conductor, while the hydrogen ions are conducted through the

Electrolytes migrate to the cathode side, where they combine with the electrons and oxygen atoms to form water molecules. Different electrolytes, which can consist of liquid or solid substances, can be used here. Heat is released during the process. The operating temperature is determined by the electrolyte used. For example, it is 80 ° for AFC potassium hydroxide solution, between 70 and 90 ° for PEMFC polymer film, and between 80 and 130 ° for a solid membrane DMFC.

The water or steam produced during the process is highly pure and is usually released into the open without any further use.

It is an object of the invention to provide a system for using the on the

Provide fuel point resulting water.

The object is achieved by the subjects of the independent claims. Advantageous embodiments are the subject matter of the dependent claims of the following description and of the figures.

Disclosure of the invention

According to one aspect, a water tank system for a fuel cell powered vehicle is provided. The water tank system has a water separator, for example a cyclone or cyclone separator, and open a water tank. The water separator is set up to separate water from water vapor and has a feed line for receiving

Water vapor from a fuel cell stack, and a discharge line to output the separated water. The water tank is set up to store the water from the water separator and, for this purpose, has a filling opening which is connected to the discharge line of the water separator and a filling opening for filling the tank with the separated water

Extraction device for extracting the water from the water tank. The supply and discharge lines for the steam and water exist

advantageously made of plastic.

A water separator can consist of a metal grid, for example, on which the water contained in the water vapor condenses due to its heat dissipation ability. In general, a water separator is an arrangement by which water condenses. One form of such an arrangement is, for example, a cyclone. Under a cyclone or cyclone separator there is thus a

Understood water separator, which consists essentially of a container that is shaped, for example funnel-shaped, conical or cylindrical, that air flowing in from the side along the outer wall rotates spirally downwards, for example, and is then discharged upwards within the spiral. If the outer wall is cooled, the water of the water vapor can condense over a large area on the surface of the inner wall, which is thus also cooled, and can be collected or discharged below. A grid for droplet formation and condensation of water vapor can also be attached to the inner wall of the cyclone.

The extraction device can be active components and / or passive

Have components. In the simplest case, the water tank only has an overflow pipe. To achieve the desired applications, however, active components such as a pump are required, as described below.

Thus, according to the first aspect, the water contained in the water vapor is not released directly into the environment, but is first collected in a water tank, and is thus available for use for various purposes

Applications available. This includes, for example, an optimization of the Air compression through water injection when supplying air to the fuel cell stack and flexible humidification of the cathode air or the anode path through water injection.

Furthermore, an emergency cooling reservoir can be provided, which can be used if a component in the vehicle is threatened with overheating. But also in general, excess water can be used

Evaporative cooling can be used for components to be cooled by applying the water to the components in a metered manner.

Another application is the humidification of indoor air or

Air conditioning of the vehicle. This is achieved, for example, by atomizing water taken from the tank and adding it to the air flow of the air conditioning system.

The water can also be used for electrolysis. Due to the purity of the water, it is particularly suitable for electrolysis through coupling with an electrolyzer. This can, for example, after the

Parking the vehicle at home.

Since the water is extremely pure, it can also be used as drinking water. The water can also optionally be mineralized and made available to the vehicle occupants via suitable lines on a tap, such as a tap or a machine for hot or cold drinks. In addition to being used as drinking water, it can also be used as service water. Especially with larger ones

The water can be used for flushing toilets or a shower in passenger transport vehicles such as buses or campers. Another application is the use of the water for a windshield wiper, e.g. the windscreen, the light, etc. This increases the maintenance intervals for these systems. Excess water can be specifically drained off.

According to one embodiment, the water separator including the supply line is at least partially integrated into the water tank. Although this reduces the usable space of the tank, it also advantageously reduces the space space required to install the water tank system in the vehicle is reduced. Only the water separator can also be partially integrated into the water tank, and the supply line is attached outside the water tank, but this reduces the space-saving effect. The integration or partial integration in connection with a flexible shape of the water tank enables flexible installation according to the various spatial conditions

different vehicle types possible.

According to one embodiment, the water separator is connected to a condenser which is set up to absorb any residual water vapor emerging from the water separator and to condense the water contained therein and to release the condensed water. Cooling fins can be attached to the condenser so that it can pass through their

Heat dissipation the temperature of the water vapor or the condensed water is reduced, and the condenser can thus also act as a heat exchanger. A condenser proposed here thus has the function of a water separator and a heat exchanger.

According to one embodiment, the water separated by the water separator and collected in the water tank and / or the condensed water from the condenser is fed to an actuator for provision for use, such as one of the applications described above. The condensed water from the condenser can be made available directly to an application, for example a cooling application, but it can also be fed into the water tank and collected there.

According to one embodiment, the water tank system furthermore has an equipment carrier on which the actuator is mounted. The equipment carrier also has at least one sensor and a pump for conveying the water from the water tank into a pressure line. The water tank as well as the built-in components and the equipment rack are resistant to ice pressure, so that damage due to possible freezing of water is excluded. Furthermore, a heater can be attached to the equipment rack in order to prevent or reverse ice formation at low temperatures. The at least one sensor can, for example, be a fill level sensor for measuring the water level

Temperature sensor for recording the water temperature or a pressure sensor be part of a measurement and control system for pumping water into a pressure pipe.

According to one embodiment, the equipment carrier is welded or tightly welded into the water tank, i.e. into the tank bladder, for example by plastic welding. This allows the water tank with the equipment rack to be produced as a module. This allows a flexible - the respective

Vehicle / installation space adapted tank bladder - and a standardized equipment rack. The lines can be made of flexible plastic. This enables a compact and space-saving structure with simple assembly.

According to one embodiment, the extraction device has a pump return arrangement which is set up to provide a return of the pump into the water tank or back to the pump. Different feed pumps for water can be used. The pump for

Water pumping can be equipped with an overflow valve, a pressure valve or a pressure relief valve. Forms of realization are

for example a pump with a regulated overflow bypass, a pump with a throttle as an overflow bypass or a pump with a throttle as an overflow bypass with a return to the water tank. A variant with a controlled overflow bypass valve is also possible, with the return flow being fed directly into the tank.

In the water tank system, the pressure line for providing the water to different consumers can have branches. The lines of the branches can have different pressures and temperatures. A heater can be integrated into one or more of the branches. The heaters can be controlled the same or differently, so that an individual temperature is available depending on the application or consumer. Furthermore, the supply of the water from the branches to the consumers can be done via metering devices, e.g.

Dosing valves, take place so that the water flow is restricted.

Thus, a water tank system is provided for a different, flexible and needs-based use of the same medium water, which enables a responsible use of water, in particular also for use in regions with a lack of water. The

Product water release to the environment is reduced. For example, freezing puddles at red lights are avoided in winter. The separated water can be used for any purpose. The integrated and closed system enables advantageous use of resources in humidity and temperature management. With regard to the cost-effectiveness in production, a standardized device carrier can result in high

Quantity and thus a reduction in costs can be achieved, and the flexible tank bladder allows flexible integration into different vehicles and installation spaces.

According to a further embodiment, the water tank system has a control device for acquiring sensor data from a sensor or several sensors and for controlling the one or more actuators based on the sensor data in the water tank system. The sensor data are, for example, temperature data of the water in the water tank, in the pipes or any components in the vehicle that need to be cooled, on the basis of which pumps, valves or heating can be controlled. By including the fill level, overflow or idling can be prevented or, for example, switching on a pump if there is no water available. The control device has logic circuits, for example in logic components such as FPGA, CPLD, processors, microprocessors, ASICs, or simple logic modules, as well as analog and digital control circuits, interfaces to sensors and actuators. The control device can also have analog-to-digital and / or digital-to-analog converters, as well as integrated or external ones

Memory cells in which sensor data, characteristic values and program elements can be stored.

According to one exemplary embodiment, a program element is provided which, when it is on a control device, has one of the above-described

Water tank system is running, the water tank system instructs you to perform the following steps:

- Feeding water vapor from a fuel cell reaction via a feed line to a water separator for separating water that is collected in a water tank; - Acquisition and processing of sensor data to determine the water level in the

Determine water tank;

- Controlling an actuator on the basis of the recorded sensor data and / or user inputs; and

Conveying water from the water tank to provide the water for use.

The program element thus contains the logic for evaluating the

Sensor data and for controlling the actuators. The program element can also have a user interface in order, for example, to react to an actuation of a digital or analog button in order, for example, to provide water with a specific temperature and quantity through the water tank system.

According to one exemplary embodiment, a computer-readable medium, such as, for example, the integrated or external memory cells mentioned above, is provided on which the program element is stored.

According to a second aspect, a vehicle is provided which has a water tank system as described above.

According to a third aspect, a method for providing water through a water tank system for a vehicle operated with fuel cells is proposed. The procedure consists of the following steps:

- Supply of water vapor from the fuel cell reaction of the

Fuel cells via a feed line to a water separator, e.g. a cyclone, to generate condensed water;

- collecting the condensed water in a water tank;

- Conveying the condensed water from the water tank to provide the condensed water for use.

The method can take further steps as described in the

Have water tank system. In particular, the remaining water vapor after being fed to the water separator can be used for another

Water separator, for example a condenser, are fed so that the water of the remaining water vapor can condense and is available via a further discharge to an application or a feed to the water tank. Furthermore, the conveying of the condensation water from the Water tank can be accomplished in particular by a pump, the pump having the properties described above, such as a

May have return arrangement and / or an overflow device. Furthermore, the water delivered from the water tank or

Condensation water via a branching pressure line or a branching rail and several different metering valves

Applications are fed. The water can also be in

Water tank or in the pipes.

Brief description of the drawings

In the following, exemplary embodiments of the invention are explained in more detail with reference to the schematic drawings. Here shows

1 shows a block diagram of a water tank system according to a first

Embodiment,

2 shows a block diagram of a water tank system according to a second exemplary embodiment,

3 shows a block diagram of a water tank system according to a third embodiment,

4 shows a flow diagram of a method for providing water by a water tank system according to an embodiment,

5 shows a block diagram of a vehicle with a water tank system according to an embodiment.

Execution forms

1 shows a water tank system with a tank 102, a cyclone 104 as a water separator, a filling opening 110 and a removal device 108. The cyclone 104 has a feed line 106 which transports the water vapor that is generated in the fuel cell to the cyclone 104. The water vapor rotates in the cyclone 104 in a spiral. The water of the water vapor, which drips or flows into the water tank 102 via the filling opening 110, condenses on its inner wall, which is cooled by fresh outside air which surrounds the cyclone. The water can be withdrawn from the water tank via the discharge line 112, the water either being active via the

Removal device 108, for example by a pump, can be removed or through a valve that protects the water tank from overflow. The over The air flow entering the cyclone 100 via the supply line 106 is diverted via the line 114.

The water vapor can also come indirectly from the fuel cells or the fuel cell stack. For example, the compressed air that is supplied to the fuel cells for reaction with hydrogen can be humidified by a humidifier. For this purpose, the water vapor from the

Fuel cells are used, which is first fed to the humidifier and from there to the cyclone.

FIG. 2 shows a further exemplary embodiment of the water tank system 100, in which the cyclone 104 is partially integrated into the water tank 102. The feed line 106 to the cyclone 104 is also integrated into the water tank 102. This reduces the space required for assembling the water tank system 100, but at the expense of the water tank volume.

3 shows a third exemplary embodiment of a water tank system 100 which, in addition to the water tank 102 and the cyclone 104, also has a condenser 302 and an equipment carrier 310 and a control device 320. The air flow from the cyclone 104, which is discharged via the line 114, flows into the condenser, which contains cooling grids on which the water of the water vapor remaining after flowing through the cyclone 104 is condensed and discharged downwards via the line 306. The airflow in that

The condenser 302 is finally released via the line 304 to e.g. the environment as exhaust air. The cyclone 104 further has cooling fins 308, so that the wall of the cyclone is effectively cooled and favorable conditions for the condensation of the water on the inner wall of the cyclone are created. The condensed water arrives at the filling port 316

Water tank 102.

Furthermore, FIG. 3 shows a venting device 312 through which the air can escape via the line 318 when the tank is being filled. The

Ventilation device 312 is preferably protected against ingress of dirt from the surroundings, e.g. by using an air-permeable membrane.

The tank ventilation can optionally also be active, ie with a valve. The device carrier 310 has a heater 312, a pump 314 and

various sensors, such as an optional fill level sensor, which is e.g. based on the ultrasonic principle, an optional

Pressure sensor, an optional thermal sensor, or other sensors. The heater can thaw frozen water or at least part of the frozen water locally in the area of the suction port of the pump. The heating principle can be different here. In one variant, the heater is an electric heater. Alternatively, it is also possible to completely or partially thaw frozen water in the water tank system using the coolant of the fuel cell. In this variant, the equipment rack contains connectors for the coolant. The device carrier 310 also has a plug for the electrical / electronic connection of actuators and sensors and optionally a filter in the suction area of the pump.

The equipment carrier and the tank bladder are connected by means of a tight connection, e.g. by plastic welding.

The water from the water tank can thus be pumped into the pressure line 112 or a rail in a controlled manner via the feed pump 314 for water, so that it can be fed to an application. There is at least one

Connection stub for pressure line 112 implemented. The feed pump 314 for water can in principle be implemented using different feed principles and drives, such as a rotary motor, a lifting magnet, etc. Pumps with an overflow throttle or an overflow valve can preferably be used. A possible return of the pump can take place directly in the tank or in the suction path of the pump. The water can from the

Pressure line 112 can be metered via devices such as metering valves transported to the application. For example, inexpensive metering valves from combustion technology can be used as metering valves, such as valves for gasoline injection. The rail enables

Delivery of water to various uses. The rail can be realized with a flexible pressure hose and various

Branches included. The line system can optionally be designed with an integrated heater. The lines can be made resistant to ice pressure (flexible material) and / or can also be emptied if there is a risk of frost. Partial emptying is also possible. The system 100 can also be expanded by adding rainwater from the chassis of the vehicle through a particle filter and, if necessary, additionally through a chemical filter, for example an activated carbon filter

Water tank system 100 is directed.

FIG. 4 shows a flow diagram of a method 400 for providing water by a water tank system according to an exemplary embodiment. Method 400 has the following steps:

- Supply 402 of water vapor from the fuel cell reaction of the

Fuel cells 502 via a feed line to a water separator 104 for generating condensed water.

- Collecting 404 the condensed water in a water tank 102, and

Conveying 406 the condensed water from the water tank 102 to

Provision of condensation water for use.

5 shows the water tank system 100 in a vehicle 500.

Advantageously, the place of condensation is thermally shielded from the stack as well as possible, e.g. by a sufficient distance or by insulation, in order to avoid the condensation heat being transferred back to the stack. The tank bladder can preferably have a shape that is adapted to the installation space of the vehicle, while the device carrier with actuators, sensors and connectors can remain the same, which has a correspondingly positive effect on costs and quantities.

Warm to hot water vapor emerging from the fuel cell 502 is condensed and, depending on the temperature of the steam and the pipelines, either collected in the water tank 102 for later use or, at a high temperature, condensed in a chimney with a large surface and back to the fuel cell 502, i.e. to the surface of the outside area, or out of condenser 302 or heat exchanger in contact with a fuel cell 502. At the point of the desired condensation, a water separator 104, for example a wire mesh, can be attached as a condenser. In addition, a cyclone 104 can be installed in the feed 106, which additionally promotes condensation. The water tank system 100 is also supplied with outside air 504, which surrounds the cyclone 104 for cooling. The air stream 114, 304 from the cyclone 104 or the condenser 302 is released into the environment. Condensed water is available from the water tank 102 or the condenser 306 on the lines 112 and 306, respectively. The control unit 320 for data acquisition and for controlling the actuators is via an interface with the

Water tank system 100 connected.

Claims

Expectations

1. Water tank system (100) for a vehicle operated with fuel cells, comprising:

a water separator (104), set up to separate water from water vapor, with a feed line (106) for receiving water vapor from a fuel cell stack, and a discharge line (110) for outputting the separated water;

a water tank (102) set up to store the water from the water separator (104)

a filling opening (110), which is connected to the discharge line of the water separator (104), for filling the water tank (102) with the

separated water.

2. Water tank system (100) according to claim 1, wherein the water separator (104) including the supply line (106) at least partially in the

Water tank (102) is integrated.

3. Water tank system (100) according to claim 1 or 2, wherein the

Water separator (104) is connected to a condenser which is set up to absorb a residual water vapor emerging from the water separator (104) and to condense the water contained therein and to release the condensed water.

4. Water tank system (100) according to one of the preceding claims, wherein the water tank system (100) is further configured to supply water from the water tank (102) and / or from the condenser (302) to an actuator for providing the water for use of the water .

5. Water tank system (100) according to one of the preceding claims, further comprising an equipment carrier (310) on which the actuator (312, 314) is mounted, and which also has a sensor and / or a pump (314) for conveying the water from the water tank (102) into a pressure line (112).

6. Water tank system (100) according to one of the preceding claims, wherein the equipment carrier (310) is welded into the water tank (102).

7. The water tank system (100) according to any one of the preceding claims, wherein the water tank system (100) further comprises a removal device (108) with a pump return arrangement which is set up to return the pump (314) to the water tank (102) or to the pump (314) to be provided back.

8. Water tank system (100) according to one of the preceding claims, wherein the pump (314) has an overflow device.

9. water tank system (100) according to one of the preceding claims,

further comprising a control device (320) for acquiring sensor data from a sensor or several sensors and for controlling an actuator or several actuators (312, 314) based on the sensor data in a water tank system (100).

10. Vehicle (500), comprising a water tank system (100) according to one of the preceding claims.

11. The method (400) for providing water through a water tank system (100) for a vehicle (400) operated with fuel cells (502), comprising the steps:

Feeding (402) water vapor from the fuel cell reaction of the fuel cells (502) via a feed line to a water separator (104) for generating condensed water;

Collecting (404) the condensed water in a water tank (102); and

Conveying (406) the condensed water from the water tank (102) to provide the condensed water for use.