Electrically operated vehicle

Abstract

The invention relates to an electrically operated vehicle containing an electrically rechargeable vehicle battery for supplying an electric drive for moving the vehicle; a tank for receiving a liquid or gaseous fuel; and a fuel cell which is operated using fuel from the tank for heating a passenger compartment, vehicle components, and / or the battery of the vehicle. The invention is characterized in that the tank and the fuel cell form modules with which the vehicle is retrofitted.

Description

[0001] Patent application

[0002] H2 Power 'n' Heat GmbH, Templiner Straße I 9B, 14473 Potsdam

[0003] Electric vehicle

[0004] Technical area

[0005] The invention relates to an electrically powered vehicle comprising

[0006] (a) an electrically rechargeable vehicle battery for supplying an electric drive for the propulsion of the vehicle;

[0007] (b) a tank for containing a liquid or gaseous fuel; and

[0008] (c) a fuel cell powered by fuel from the tank for heating the passenger compartment, vehicle components and / or vehicle battery of the vehicle.

[0009] A vehicle can be moved on land, water, or air. In particular, a vehicle can be a passenger car, truck, mobile home, sailboat, ship, airplane, motorcycle, and the like.

[0010] In the past, most vehicles were powered by fossil fuels, such as combustion engines. To achieve climate neutrality, other solutions are now being sought. In particular, vehicles with electric drive and a powerful vehicle battery are already available as standard equipment. Fuel cell drive systems are also known.

[0011] In internal combustion engines, energy stored chemically in fuel is first converted into thermal energy and then into mechanical work. In electric vehicles, the energy stored in a battery is converted into mechanical work via an electric drive. In a fuel cell, the energy stored chemically in a fuel, such as hydrogen, is converted directly into electrical energy and then into mechanical work.

[0012] In addition to these drive systems, hybrid systems are also known. These utilize a conventional combustion engine and an additional electric drive system with a battery as an energy storage device. As long as the battery is supplying power, the vehicle is powered exclusively by electric energy. After that, the combustion engine serves as the primary drive. Depending on the design, the battery can be recharged through recuperation or, in the case of plug-in hybrids, from external energy sources. Hybrid drives utilize two primary drives and two associated energy storage systems—a battery and a fuel tank. These systems are complex and heavy, thus increasing manufacturing costs, maintenance effort, and energy consumption.

[0013] The disadvantages of purely electric vehicles are their limited range, the long charging time, and the short battery life. These adverse effects are more pronounced at low temperatures, particularly in cold regions, at night, and in winter. At low temperatures, battery efficiency decreases. This makes it necessary to heat the battery. The heating is powered by energy from the vehicle battery. The same applies to the passenger compartment, which also requires electrical heating. This reduces the vehicle's range.

[0014] State of the art

[0015] DE102009035471A1 discloses a vehicle with a temperature control device for temperature control of a vehicle battery in a vehicle in which a heat engine or fuel cell is provided as the main drive and the vehicle battery is provided for operating auxiliary units.

[0016] DE102011079640A1 discloses a cooling system for a fuel cell system with heat extraction. The system comprises a stationary energy supply system with a fuel cell system, a fuel cell cooling circuit for cooling the fuel cell system, and an accumulator cooling circuit for cooling an accumulator. The heat energy between the fuel cell cooling circuit and the accumulator cooling circuit is exchangeable.

[0017] DE102014009772A1 discloses an electric vehicle with a fuel cell system. The fuel cell system is designed to recharge the electrical energy storage device. DE102017006158A1 discloses a method for operating an electric vehicle with a range extension by emptying an energy carrier before recharging energy.

[0018] DE102011076737A1 discloses a device for providing electrical energy, in which the electrical energy storage device is thermally coupled to the fuel cell assembly by means of a heat transfer arrangement. The known fuel cell assembly is permanently installed in the vehicle. The associated additional costs and weight therefore arise even when they are not actually needed, for example, when the vehicle is to be used in warmer climates or only in summer, or when the vehicle is regularly parked in a garage, where additional heating of the battery is not necessary.

[0019] Disclosure of the invention

[0020] The object of the invention is to create an electrically powered vehicle of the type mentioned above that enables a long range even at low temperatures. It is also an object of the invention to create further possible uses for fuel cells.

[0021] According to the invention, this object is achieved in that the tank and the fuel cell form modules with which the vehicle is retrofitted. Vehicles for which there is no need for additional heating of the battery, for example because the vehicle is only used at higher temperatures, can then drive without a fuel cell and tank. This saves costs and weight, allowing a greater range to be achieved. Vehicles that are also intended to be used at low temperatures can be retrofitted with the modules. The retrofitting of the otherwise unchanged vehicle can be permanent or temporary, for example for the cold season. Retrofitting with modules enables the production of identical vehicles for both applications - with and without a fuel cell - and thus in higher quantities. A higher unit volume has a beneficial effect on production costs.In addition to the passenger compartment and vehicle battery, vehicle components, especially electrical components such as the engine, inverter, etc., can also be heated.

[0022] A particular advantage of the modules is that they are also available for other uses independent of the vehicle. For example, the modules can be used as a combined heater and power generator for mobile applications in camping, emergency supplies, emergency shelters, events, and the like.

[0023] It is particularly advantageous if the tank forms a separate module and is detachably installed in the vehicle. This eliminates the need for separate refueling. Rather, the tank can be replaced as a whole, similar to cartridges in a soda maker. For this purpose, a deposit system can be established, for example, or existing pressurized container systems can be used.

[0024] The fuel cell primarily serves as a heat source. High efficiency is achieved when the electrical power generated during operation is utilized. This can be done directly by connecting electrical consumers. However, it is advantageous for the fuel cell to be connected to the vehicle battery, allowing electrical energy to be fed into the vehicle battery during operation. Then, only one connection is required, and the electrical consumers are supplied in the usual way via the vehicle electrical system.

[0025] In an advantageous embodiment, the fuel tank is a hydrogen tank, and the fuel cell is operable with hydrogen. It is understood that other fuel cell technologies are also possible.

[0026] A control unit can be provided for controlling the fuel cell, which operates the fuel cell at least partially in accordance with a temperature value. Thus, the fuel cell can be operated whenever the temperature of the energy storage unit of the vehicle's main drive drops below a threshold. It can also be operated when, for example, the passenger compartment needs to be heated.

[0027] A method for operating a fuel cell may comprise the steps:

[0028] (a) determining a temperature value;

[0029] (b) controlling the temperature value by generating thermal energy with the fuel cell to a set value; where

[0030] (c) electrical energy generated during the operation of the fuel cell, stored, or used for an electrical consumer. The temperature value can represent the temperature in the passenger compartment of a vehicle or a vehicle battery. However, other temperature values, such as those in the cargo area, can also be regulated to a setpoint.

[0031] The electrical energy is advantageously stored in a vehicle battery intended to power a vehicle. This can extend the range. Alternatively or additionally, the electrical energy can be fed into the electrical system of a vehicle with one or more electrical consumers. This is particularly useful when a consumer requires continuous electrical energy, such as a refrigeration unit. This minimizes energy losses and aging in the battery due to intermediate storage.

[0032] The object of the invention is also achieved by an auxiliary unit for retrofitting a vehicle with an additional energy source, comprising

[0033] (a) a tank for containing a liquid or gaseous fuel;

[0034] (b) a fuel cell for generating thermal and electrical energy;

[0035] (c) a control unit for controlling the operation of the fuel cell as a function of a temperature and / or the battery level.

[0036] Such an auxiliary power unit can be installed in any production vehicle. Installation is carried out as needed, meaning the costs and effort only arise when the vehicle is to be driven in low temperatures and a long range is desired. However, the auxiliary power unit can also be used for other purposes. It is particularly advantageous if the tank is detachably connected to the module. Then the tank can be refilled, for example, while installed, or replaced with a full tank.

[0037] Advantageously, the tank, the fuel cell, and the control unit are arranged in a jointly mountable module having interfaces via which the module can be connected to the respective functional units of the vehicle. The module can then be installed and removed by automotive mechatronics engineers and other specialists who are not familiar with fuel technology. It is sufficient if they know which interfaces the module is connected to in the motor vehicle. Embodiments of the invention are the subject of the dependent claims. One exemplary embodiment is explained in more detail below with reference to the accompanying drawings.

[0038] Definitions

[0039] In this description and the appended claims, all terms have a meaning familiar to the person skilled in the art, as defined in the specialist literature, standards, and relevant internet pages and publications, particularly lexical ones, such as www.Wikipedia.de, www.wissen.de, or those of competitors, research institutes, universities, and associations. In particular, the terms used do not have the opposite meaning to what the person skilled in the art would understand from the above publications.

[0040] Short description of the drawings

[0041] Fig. l is a schematic representation of a vehicle to illustrate the installation variants of a fuel cell module.

[0042] Fig.2 is a perspective view of a fuel cell module with housing and pressure vessel for hydrogen.

[0043] Fig.3 shows the arrangement from Figure 2 with support structure without housing.

[0044] Fig.4 shows the arrangement from Figure 3 without support structure.

[0045] Fig.5 shows the arrangement of Figure 4 from a different perspective.

[0046] Fig.6 is a side view of the arrangement of Figure 5 without pressure vessel.

[0047] Fig.7 is a plan view of the arrangement of Figure 6.

[0048] Fig.8 is a side view of the arrangement of Figure 6.

[0049] Fig.9 shows part of the arrangement from Figure 6 with water / coolant / power

[0050] Connections on the underside of the support structure.

[0051] Fig.10 shows the arrangement of Figure 6 on a base in use as a stationary fuel cell for providing electrical energy.

[0052] Fig.11 is a perspective view of the base of Figure 10 without the housing.

[0053] Fig.12 shows the arrangement of Figure 11 from a different perspective.

[0054] Fig.13 is a side view of the base of Figure 11.

[0055] Fig.14 is a schematic representation of the circuits for the mobile application of the arrangement of Figure 2.

[0056] Fig.15 is a schematic representation of the cathode subsystem from Figure 14.

[0057] Fig.16 is a schematic representation of the anode subsystem from Figure 14.

[0058] Figure 17 is a schematic representation of the cooling circuit subsystem. Figure 18 is a variant of Figure 14 with a dedicated cooling unit, when heat is not removed solely by the vehicle.

[0059] Fig.19 is another variant of Figure 14 with two separate heat exchangers for e.g. a battery and the cabin

[0060] Fig.20 is a schematic representation of the circuits for the stationary application of the arrangement of Figure 10.

[0061] Description of the embodiment

[0062] Figure 1 shows a vehicle generally designated 10. In the present embodiment, the vehicle 10 is a passenger car. It is understood that the invention can also be applied to any other vehicle, i.e., trucks, mobile homes, sailboats, ships, airplanes, motorcycles, and the like. The vehicle has a hollow space at the front or rear, such as a trunk 12 or 18, respectively. A fuel cell module 14 can be installed in the trunk 12 or 18. The fuel cell module 14 is supplied with hydrogen from a tank 16 via a supply line 20.

[0063] Figure 2 shows the fuel cell module 14 and the tank 16 in detail. In the present embodiment, the tank 16 comprises two pressure vessels 22, each with a volume of, for example, 6 liters and a pressure of, for example, 350 bar or 700 bar, which are filled with liquid hydrogen. Depending on the fuel cell, other gases or liquids can of course also be used in more or fewer pressure vessels 22.

[0064] The pressure vessels 22 are bottle-shaped and secured in a crash-proof manner to a common base plate 24. Tensioning straps 26 are provided for this purpose. It is understood that other crash-proof fastenings are also possible instead of tensioning straps. The base plate 24 can be firmly screwed into the vehicle or secured in another way before the pressure vessels 22 are attached. This facilitates the installation of the base plate 24. The tensioning straps 26 can also be operated by a layperson, allowing the pressure vessels 22 to be easily removed and replaced, serviced, and / or filled as needed.

[0065] The supply line 20 to the fuel cell module 14 is provided with a manually operated shut-off valve 28 on the module side. It is understood that self-closing shut-off valves are also possible instead of a manually operated shut-off valve. Upstream of the shut-off valve 28, T-pieces 30 and 34 or a corner piece 32 are installed in the supply line 20. A first pressure vessel 22 is connected via the T-piece 30. It is understood that additional pressure vessels can also be connected via additional T-pieces. Another pressure vessel is connected to the corner piece 32. If only one pressure vessel 22 is provided, a T-piece 30 is not required. It is understood that a linear connection is also possible instead of a corner piece 32.

[0066] A filling connection 36 with a valve opening in the direction of the supply line is connected to the T-piece 34. The pressure vessels 22 can be filled and refilled via the filling connection 36 when the shut-off valve 28 is closed. Instead of filling the pressure vessels 22 via the filling connection 36, empty pressure vessels 22 can also be replaced with full pressure vessels. To do this, a quick-connector 38 is opened and the tensioning straps 26 are released. The quick-connector 38 can, for example, be designed similarly to commercially available quick-connectors for gardening hoses, where the opening in the pressure vessel 22 is closed by a valve as soon as the quick-connector 38 is released. It goes without saying that any other connection can also be used.

[0067] The use of replaceable pressure vessels 22 enables the use of a deposit system, so that not every gas station has to provide the required fuel at a pump. In an alternative embodiment, the tank 16 is permanently integrated into the fuel cell module 14 and enclosed together with it. Only one nozzle for filling is then accessible from the outside. The fuel cell module 14 is then somewhat larger but easier to install.

[0068] Figure 2 shows the fuel cell module 14 with a simple housing 40 made of thin sheet metal. The housing 40 serves to protect against environmental influences, dust, and unauthorized access. Figure 3 shows the arrangement from Figure 2 without the housing 40. A support structure 42 can be seen on which the housing 40 is held. The support structure 42 comprises a front 50, a rear 52, side walls 54 and 56, a base 58, and a top 60. The side walls 54 and 56 and the base 58 of the support structure 42 are made of a solid material, for example, 4 mm thick steel, to prevent damage to the components contained therein as much as possible, even in the event of an accident.

[0069] The interior of the essentially cuboid-shaped support structure 42 is easily accessible via an opening 44 in the top 60 and several openings 46 in the side walls 54 and 56. The components of the fuel cell module 14 described below are attached to this support structure 42. The openings 44, 46 allow access to the interior and also reduce the weight of the fuel cell module 14. Furthermore, less material is required for the support structure 42. This reduces costs.

[0070] Figure 4 shows the fuel cell module 14 without side walls 54 and 56 and without the top side 60 from a first perspective, in which the front side 50 is completely visible. Figure 5 shows the same fuel cell module 14 from a second perspective, in which the rear side 52 is completely visible.

[0071] Figure 4 shows that the front side 50 has an opening 62 provided with a grid. Air is drawn in from outside through the opening 62. This is illustrated in Figure 14 by an arrow 74. The air flows through a filter and a funnel 64 into a compressor or blower 66. This is illustrated in Figures 14 and 15 by an arrow 74. In the compressor or blower 66, the air is compressed from ambient pressure in the range of 1 bar to a higher pressure of, for example, 1.3 bar and transported into the fuel cell.

[0072] The output of the compressor or blower 66 is connected to a humidifier 68 via a connecting line 70. In the humidifier 68, the water content of the air is increased. From the humidifier 68, the air is fed to the fuel cell 76 via a line 80. The fuel cell is attached to the rear wall 52 of the support structure 42 and is clearly visible in Figure 4. Increasing the air pressure and thus the amount of oxygen at the cathode 98 of the fuel cell 76 has a positive effect on the performance of the fuel cell 76, but at the same time requires more drive power at the compressor 66. The compressor 66 is the largest consumer of all components in the fuel cell module 14. The operating strategy is therefore crucial for a good overall efficiency of the fuel cell module 14. The cathode circuit is illustrated separately again in Figure 15.

[0073] Also on the front side 50 is the inlet for the fuel supply, hydrogen in the present embodiment, via the supply line 20. Behind the front side 50, a high-pressure valve 82 and downstream a low-pressure valve 84 are arranged in the line 20. The high-pressure valve 82 reduces the fuel pressure from the tank 16, for example, 700 bar or 350 bar, to a lower pressure of, for example, 10 bar. The downstream, adjustable low-pressure valve 84 regulates the fuel pressure to the required operating pressure of the fuel cell 76, for example, between 1 and 2.5 bar. The low-pressure valve 84 thus regulates the pressure to the operating pressure of the anode circuit. To avoid damage to the membrane of the fuel cell 76, the pressure difference between the anode 100 and the cathode 98 is as small as possible. An optional heat exchanger 102 serves to adapt the gas temperature to the fuel cell temperature.

[0074] The fuel is fed to the anode of the fuel cell 76 via a supply line 86. The hydrogen path (anode subsystem) described above is illustrated separately in Figure 16. It provides the required amount of hydrogen at the correct concentration, pressure, and temperature to the fuel cell 76 for the electrochemical reaction.

[0075] In the fuel cell 76, the fuel reacts with the oxygen contained in the air. The functioning of fuel cells is generally known and therefore needs no further explanation here. In principle, any fuel cell is suitable. In the present embodiment, the fuel is molecular hydrogen, and the fuel cell is a low-temperature polymer electrolyte fuel cell, also known as a low-temperature PEM fuel cell. The reaction produces heat and water. Furthermore, a voltage is generated at the electrodes.

[0076] To prevent a hydrogen shortage, more hydrogen is typically supplied to the anode 100 than the reaction consumes. The excess hydrogen can be recirculated, with excess water in the hydrogen being removed downstream of the anode 100 using a water separator 102. An actively controlled recirculation pump 106 optionally closes the circuit and feeds the hydrogen mixture to the fresh hydrogen supply line 104. The optional recirculation enables better flow through the fuel cell 76, improves water management, and reduces losses.

[0077] The water generated in the fuel cell 76 is conveyed via a line 88 to the humidifier 68. There, it is used to humidify the air entering the assembly. Downstream of the humidifier, the gas is discharged to the outside as exhaust gas via a check valve 92. The check valve can also be designed as a siphon. This is illustrated in Figure 14 by an arrow 94. Heat is generated during operation of the fuel cell 76. The heat is dissipated via a cooling circuit, generally designated 96. The cooling circuit 96 is illustrated separately again in Figure 17. Depending on the quality of the hydrogen, the present fuel cell 76 achieves electrical efficiencies of up to 40%. This means that during operation, up to 60% of the supplied energy is dissipated as heat. The heat output is thus in a similar range to the useful electrical output. The operating temperature is comparatively low, ranging from 60 to 85°C.For this reason, the exhaust gas enthalpy is low and the exhaust gas enthalpy flow reaches a share of 5-15%.

[0078] The electrical power of the fuel cell system is determined by the power of the fuel cell stack minus the power of the components. The electrical efficiency is determined by the effective power described above, the mass flow of the hydrogen, and its calorific value:

[0079] In general, the highest effective efficiency is achieved at low current densities. At high current densities, the electrical efficiency decreases due to the increasing power requirements of the components and the decreasing fuel cell efficiency. The thermal power is also determined from the power of the fuel cell stack, the supplied fuel energy, and the exhaust gas enthalpy flow. The following relationship applies to the thermal efficiency:

[0080] Relative to the hydrogen used, the overall efficiency of the fuel cell module 14 increases with the utilization of the heat. In winter operation, an overall efficiency of over 90% can be achieved. In mobile applications, the heat output can be used to heat the vehicle interior and as a heat source for the thermal management system of the vehicle battery to operating temperature. The heat from the fuel cell 76 is absorbed and dissipated via the cooling circuit 96. The design of the thermal management required for this depends not only on the connection to the fuel cell 76, but also on the auxiliary units used and their integration into the vehicle. The main task of thermal management is to monitor the temperature of the components, regulate the optimal temperature range, and ensure rapid start-up after a standstill. Figures 14 and 17 show the required components and their interconnection.

[0081] The coolant is passed through a filter 112 to a coolant pump 110. This pumps the coolant through the fuel cell 76, where the reaction heat is absorbed. A portion of the coolant is passed via a throttle valve 114 to electronic components 116 in the vehicle, which are to be cooled and where heat is also absorbed. The warm coolant streams are recombined at a T-piece 118. From there, the warm coolant can be pumped to the vehicle battery 120 and / or into the passenger compartment. There, the heat is dissipated. If no heating is to occur, the coolant can be passed via a bypass 122. A bypass valve 124 is provided for this purpose. The bypass valve 124 deactivates the thermal coupling in order to prevent any excess heat from being introduced into the vehicle, for example because the fuel cell takes too long to shut down.

[0082] By controlling a coolant pump 110 and the various valves, the optimal temperature range for the fuel cell module 14 is regulated. The 3-way valve 124 ideally distributes the heat flow to a cooler or a heat exchanger for heating the vehicle battery 120 or the vehicle interior. The cooling medium must be electrically insulating, as it is in direct contact with the conductive bipolar plates. This can be achieved, for example, by using deionized coolants.

[0083] An integrated control unit 126 on the floor of the support structure 42 controls, regulates, and monitors operation. It includes the various operating modes, such as the start-up process, the three operating points, and the shutdown process. The controller 126 communicates with the vehicle control unit. In particular, signals relating to the vehicle's temperatures and battery status are read out at the control unit diagnostic interface. Specifically, the control unit 126 receives signals via signal lines that represent the temperature of the battery 120, the passenger compartment, and the fuel cell 76. The control unit 126 also receives signals that represent the charge state of the battery 120. The fuel cell module 14 can replace the otherwise standard heater. However, the measuring points remain the same. If a temperature falls below a threshold, the fuel cell 76 is switched on.

[0084] A heat exchanger is provided in the housing for heat transfer. The inlet and outlet of the heat exchanger each form interfaces for water or glycol lines. The filling opening, for example, is suitable for connection. Alternatively, the lines can be broken open and fitted with a T-piece. Water lines are connected to the heating circuit, for example, of the passenger compartment and / or the battery and / or other components. The control system regulates the temperature at the vehicle outlet of the heat exchanger. If only signals for the inlet temperature are available, the heat loss value for the vehicle can be determined or estimated to account for path losses.

[0085] The fuel cell module 14 provides energy that is cost-effective, makes optimal use of hydrogen, and is low in complexity. Instead of combining a large fuel cell with a small battery, as is common today in fuel cell vehicles, the present invention takes the opposite approach. A small fuel cell, which delivers, for example, up to 11 kilowatts of electrical power, is installed in an electric vehicle with a standard storage capacity. This approach not only significantly reduces costs and the packaging, but also the application effort. To improve the service life of the fuel cell, it can be operated in a stationary mode at, for example, three operating points. Since the load points are charging points of the vehicle battery, this also aids integration and integration into the vehicle. Examples of operating points are listed below:

[0086] 1. Low load point (near idle) with an electrical power of 2.1 kW and a thermal power of 3.0 kW. This serves to heat the battery at low temperatures.

[0087] 2. Medium load point with an electrical output of 3.6 kW and a thermal output of 6.2 kW. This is useful, for example, for operating critical consumers in the vehicle, such as lights and fans. 3. High load point with an electrical output of 11.0 kW and a thermal output of 20.5 kW. This load point is particularly useful for additional consumers, such as when operating a cooling or air conditioning system or a mobile office.

[0088] There are various activation conditions. These include thermal activation conditions, when the vehicle is switched off, no charging current is flowing, the outside temperature is below 15°C, and the battery's charge level allows charging, i.e., the battery is not already fully charged. Electrical activation conditions include the vehicle being moved and the range indicated by the navigation system is insufficient to reach the destination with the current battery charge level. Here, too, the battery's charge level must allow charging. Operation is generally advisable when the battery temperature is below the optimal operating temperature of, for example, 15°C.

[0089] Retrofitting vehicles with electric main drive is advantageously only necessary if temperatures in the locations where the vehicle is driven actually fall below the threshold of, for example, 15°C. Unlike heat pumps, fuel cells operate even in cold temperatures, thus preventing the battery from freezing. The fuel cell module can have its own small battery for its own operation and the start-up phase.

[0090] In addition to supplying vehicles with heat and electrical energy, various special applications are possible without modifying the fuel cell module 14. For example, the module 14 can be used to power a cooling system in refrigerated vehicles, as well as the heating and power supply of mobile homes, caravans, and boats, especially when the engine is switched off. In addition to mobile applications, the fuel cell module 14 can also be used in stationary applications, such as camping or as an emergency power supply for agricultural machinery, construction machinery, for firefighters, and in disaster relief as a replacement for emergency power generators powered by climate-damaging fossil fuels.

[0091] A second embodiment, in which the fuel cell module 14 is used in a stationary manner, is illustrated in Figures 9 to 13 and Figure 18. Terminals 200 for power transfer are provided in the base 58. The terminals 200 are connected to an inverter 130 in the module 14, where the electrical energy tapped from the fuel cell 76 is converted into a desired voltage, for example, 12, 24, 48, 230, or 400 volts. Terminals 202 are also provided for connection to the water circuit.

[0092] The fuel cell module 14 is mounted on a base 204. This can be seen in Figure 10. The base 204 has the external shape of a table with four legs 206. Power is supplied via conventional sockets 208 on the front 210 of the base 204. The tank 16 can be attached to the panel on the rear of the base 204 using the base plate 24.

[0093] Figure 11 shows the base 204 without its casing. The base 204 is provided with a base 212 slightly above ground level. A converter unit 222 is mounted on the base 212, which converts the voltage provided by the fuel cell module 14 into a voltage required by the consumer, for example, an alternating voltage of 230 V or 400 V. The power is transferred to protruding terminals 214 on the top side of the base 204, which interact with the terminals 200 on the bottom side of the module 14.

[0094] A screw-capped refill port 216 for cooling water on the base 204 allows the cooling circuit 224 and expansion tank 218 to be filled and refilled with coolant. The coolant pump 226 can be seen in Figure 13.

[0095] A fan 220 is also arranged on the base 212. The fan 220 serves to dissipate heat to the outside into the area below the base 212. A capacitor 228 is arranged above the fan 220. This capacitor is clearly visible in Figures 11 and 13.

[0096] If the fuel cell module 14 is to be used stationary, for example to provide emergency power, it is placed on the base 204 between two brackets 230 and 234 (Figure 11) and can be held and secured there with straps 232 to mounting brackets 236. This is illustrated in Figure 10.

[0097] Stationary use with the base 204 operates as illustrated in Figure 18: In addition to the components already described in Figure 14, a heat exchanger 238 for the fuel and the condenser 228 with fan 220 are integrated into the cooling circuit. These are located in the base 204. Figure 19 is a further variant of Figure 14 with two separate heat exchangers for, for example, a battery and the cabin 320. Figure 20 shows circuits for the stationary application of the arrangement from Figure 10. A filter 227 can optionally be arranged upstream of the pump.

[0098] The exemplary embodiments explained above serve to illustrate the invention claimed in the claims. Features which are disclosed together with other features can generally also be used alone or in combination with other features which are explicitly or implicitly disclosed in the text or in the drawings in the exemplary embodiments. Dimensions and sizes are given only as examples. Suitable ranges will become apparent to those skilled in the art from their specialist knowledge and therefore need not be explained in more detail here. The disclosure of a specific embodiment of a feature does not mean that the invention is to be limited to this specific embodiment. Rather, such a feature can be implemented by a multitude of other embodiments familiar to those skilled in the art.The invention can therefore be realized not only in the form of the embodiments explained, but by all embodiments covered by the scope of protection of the appended claims.

[0099] The terms "top," "bottom," "right," and "left" refer exclusively to the attached drawings. It is understood that claimed devices may also assume other orientations. The terms "containing" and "comprising" mean that additional, unmentioned components may be provided. The terms "essentially," "predominantly," and "predominantly" include all features that exhibit a property or content in the majority, i.e., more than all other mentioned components or properties of the feature—for example, more than 50% for two components.

Claims

Patent claims 1. Electrically powered vehicle, containing (a) an electrically rechargeable vehicle battery for supplying an electric drive for propelling the vehicle; (b) a tank for holding a liquid or gaseous fuel; and (c) a fuel cell powered by fuel from the tank for heating the passenger compartment, vehicle components and / or vehicle battery of the vehicle; characterized in that (d) the tank and the fuel cell form modules with which the vehicle has been retrofitted.

2. Vehicle according to claim 1, characterized in that the tank forms a separate module and is detachably inserted into the vehicle or the module.

3. Vehicle according to one of the preceding claims, characterized in that the fuel cell is connected to the vehicle battery and electrical energy can be fed into the vehicle battery during operation.

4. Vehicle according to one of the preceding claims, characterized in that the fuel tank is a hydrogen tank and the fuel cell is operable with hydrogen.

5. Vehicle according to one of the preceding claims, characterized in that a control unit for controlling the fuel cell is provided, which operates the fuel cell at least partially according to a temperature value.

6. Procedure for operating a fuel cell with the following steps: (a) Determining a temperature value; (b) Controlling the temperature value by generating thermal energy with the fuel cell to a setpoint; wherein (c) electrical energy generated during the operation of the fuel cell, stored or used for an electrical consumer.

7. Method according to claim 6, characterized in that the temperature value represents the temperature in the passenger compartment of a vehicle, after the vehicle radiator or a vehicle battery.

8. Method according to claim 6 or 7, characterized in that the electrical energy is stored in a vehicle battery which is intended for powering a vehicle.

9. Method according to one of claims 6 to 8, characterized in that the electrical energy is fed at least partially into the vehicle electrical system with one or more electrical consumers.

10. Method according to claim 9, characterized in that at least one electrical consumer is a cooling unit.

11. Method according to one of claims 6 to 10, characterized in that the state of charge of the battery is determined.

12. Method according to claim 11, characterized in that the fuel cell is only operated when the battery has a charge level that allows for further charging.

13. Method according to any of the preceding claims, characterized by the steps: (a) Determining a distance to a target (b) Determining the power required for the distance from the consumption and charge level of the vehicle battery; (c) Adjusting the load point to the required power.

14. Auxiliary unit for retrofitting a vehicle with an additional energy source, containing (a) a tank for holding a liquid or gaseous fuel; (b) a fuel cell for generating thermal and electrical energy; (c) a control unit for controlling the operation of the fuel cell depending on a temperature and / or the battery charge level.

15. Auxiliary unit according to claim 14, characterized in that the tank, the fuel cell and the control unit are arranged in a jointly mountable module which has interfaces via which the module can be connected to the respective functional units of the vehicle.

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