Device for detecting hydrogen in a liquid circuit and for removing hydrogen from the liquid circuit, and vehicle with such a device

Abstract

The invention relates to a device (2) for detecting hydrogen, in particular small amounts of hydrogen, in a liquid circuit (3) and for removing the hydrogen, in particular the small amounts of hydrogen, from the liquid circuit (3). According to the invention, the device (2) is characterized by - a platinum plate (4) which is arranged or can be arranged in the liquid circuit (3), and - a temperature sensor (6) designed and configured to measure the temperature of the platinum plate (4).

Description

[0001] The invention relates to a device for detecting hydrogen in a liquid circuit and for removing the hydrogen from the liquid circuit according to the features of the preamble of claim 1 and a vehicle.

[0002] As described in DE 31 51 084 C1, a method for detecting and removing small quantities of hydrogen from liquid circuits used for temperature control of metal hydride storage systems is known from the prior art. The hydrogen is separated from the liquid circuit by a gas-liquid separator and fed via a first porous wall to a hydrogen-oxygen recombination catalyst, which is connected to the outside air via a second porous wall. The porous walls have a pore diameter of 0.0001 to 0.1 mm. Hydrogen and oxygen combine at the catalyst to form water. The resulting temperature increase serves to detect the presence of hydrogen. At the same time, the escape of hydrogen into the atmosphere is prevented. Even 5 cm 3 Gas bubbles containing hydrogen can be detected.

[0003] German patent DE 10 2004 052 542 A1 describes a vehicle component and a coating material for a vehicle component. The vehicle component is a body part of a vehicle that uses hydrogen for propulsion or transports hydrogen. Under normal operating conditions, it is not exposed to gaseous hydrogen. The surfaces of the component that are exposed to released hydrogen have a coating containing a hydrogen-oxygen recombination catalyst.

[0004] The invention is based on the objective of providing a device improved compared to the prior art for detecting hydrogen in a liquid circuit of a temperature control circuit of a vehicle battery and for removing the hydrogen from the liquid circuit.

[0005] The object is solved according to the invention by a device for detecting hydrogen in a liquid circuit of a temperature control circuit of a vehicle battery and for removing the hydrogen from the liquid circuit with the features of claim 1.

[0006] Advantageous embodiments of the invention are the subject of the dependent claims.

[0007] According to the invention, a device for detecting hydrogen, particularly small quantities of hydrogen, in a liquid circuit of a temperature control circuit of a vehicle battery and for removing the hydrogen, particularly small quantities of hydrogen, from the liquid circuit comprises a platinum plate which is arranged or can be arranged in the liquid circuit. Furthermore, according to the invention, the device comprises a temperature sensor designed and configured to measure the temperature of the platinum plate.

[0008] A platinum plate is a plate, particularly a small one, made especially of platinum or a platinum alloy, or which has at least a surface coating of platinum or a platinum alloy. The platinum alloy is specifically designed such that it has platinum as its main component, particularly in a proportion that is greater, especially significantly greater, than half of the total mass and / or weight and / or volume of the alloy.

[0009] The platinum plate can also consist of a dispersed platinum mixture on a carbon support.

[0010] A vehicle according to the invention has this device, wherein the platinum plate is already arranged in the fluid circuit. The fluid circuit is, in particular, a component of the vehicle.

[0011] The vehicle includes, in particular, a battery, the fluid circuit of which is a temperature control circuit of the vehicle, designed and configured for temperature control, in particular cooling, of the battery. The battery is, in particular, a traction battery, which is intended, in particular, for supplying electrical energy to at least one electric drive motor of the vehicle for propelling the vehicle. The vehicle is, in particular, an electric vehicle or a hybrid vehicle.

[0012] In one embodiment, the fluid circuit includes oil or an oil mixture as the temperature control fluid.

[0013] In another embodiment, the fluid circuit includes water or a water mixture as the temperature control fluid, in particular a water-containing temperature control fluid.

[0014] In one embodiment, the fluid circuit, in particular the embodiment of the fluid circuit which has oil or an oil mixture as a temperature control fluid, is thermally coupled to a further fluid circuit of the vehicle via a heat exchanger of the vehicle, wherein the further fluid circuit has in particular water or a water mixture as a temperature control fluid, in particular a water-containing temperature control fluid.

[0015] The liquid circuit includes, in particular, an expansion tank, which is a component of the device. The platinum plate is advantageously arranged in this expansion tank. Alternatively, the platinum plate can, for example, be arranged at another suitable collection point for the hydrogen in the liquid circuit.

[0016] The temperature sensor is advantageously coupled with a warning unit, which is specifically designed and configured to warn of hydrogen in the liquid circuit when a temperature of the platinum plate determined by means of the temperature sensor exceeds a predetermined temperature limit.

[0017] In particular, a vehicle designed as an electric or hybrid vehicle has a high-voltage battery as its traction battery, as described above. Depending on the operating conditions, this battery must be temperature-controlled, and especially cooled. This is done as described above, for example, using a water-based temperature control fluid or an anhydrous oil or oil mixture as the temperature control fluid. However, leaks, aging, or other damage to seals can lead to water entering the oil-based or oil-mixed temperature control fluid, especially from the wider fluid circuit via the heat exchanger. Alternatively, the water-based or water-mixed temperature control fluid in the fluid circuit can come into contact with live parts of the battery.

[0018] If oil or an oil mixture is used as the temperature control fluid, it can directly flow around and thus temperature-controlled, and especially cool, the battery's live parts. However, this can also allow water to come into contact with the live parts of the battery. If water or a water mixture is used as the temperature control fluid, this is avoided by a suitable temperature control channel design. However, even here, due to the leaks described above or damaged seals, water can still come into contact with the battery's live parts. This can lead to hydrogen production within the battery, which is then transported in the fluid circuit along with the temperature control fluid.

[0019] When hydrogen, especially in small quantities, reaches the platinum plate, a catalytic recombination to form water, particularly water vapor, occurs on the platinum plate, even outside the ignition limits of hydrogen, particularly at room temperature and with a sufficient supply of oxygen. This is also known as catalytic combustion or catalytic oxidation of hydrogen. The platinum of the plate acts as a catalyst and heats up in the process. The temperature of the platinum plate is measured by a temperature sensor, allowing this heating to be detected and the presence of hydrogen in the liquid circuit to be monitored. For example, a warning unit can then issue an alert that hydrogen has formed and is present in the liquid circuit if the temperature of the platinum plate exceeds the predefined temperature limit.For example, maintenance and repair can then be recommended or arranged.

[0020] By constantly converting the hydrogen to water on the platinum plate in the manner described, an accumulation of larger quantities of hydrogen and a resulting risk of explosion are avoided.

[0021] For example, the platinum plate is located in an upper section of the expansion tank. This allows hydrogen contained in the temperature control fluid to escape from the expansion tank, rise to the top, and reach the platinum plate.

[0022] In one embodiment, a hydrogen-permeable and liquid-tight membrane is arranged between the upper and lower sections of the expansion tank. The lower section of the expansion tank advantageously has an inlet and an outlet for the fluid circuit. The hydrogen escaping from the temperature control fluid in the lower section of the expansion tank can thus pass through the membrane into the upper section and to the platinum plate. Water is produced by the platinum plate and the hydrogen, with the hydrogen being consumed and thus removed. The liquid-tight membrane prevents this water from flowing downwards into the lower section and thus into the temperature control fluid, and / or prevents the temperature control fluid from flowing into the upper section.This is particularly advantageous for the embodiment of the fluid circuit which uses oil or an oil mixture as the temperature control fluid, since this oil or oil mixture should not mix with water. However, this can also be advantageous for the other embodiment of the fluid circuit, which uses a water mixture as the temperature control fluid, in order to avoid increasing the water content in this mixture.

[0023] The water that accumulates, particularly in the upper section of the expansion tank, can be drained, for example, via a drain line, for example by opening a shut-off valve, either manually, for example during vehicle maintenance, or automatically, for example at a predetermined water level, or pumped out, for example during vehicle maintenance or automatically, for example at a predetermined water level.

[0024] As an alternative to the platinum plate, a hydrogen-permeable and, for example, liquid-tight membrane can be arranged at a suitable location in the liquid circuit and / or the battery, in particular at a location where the hydrogen collects, through which the hydrogen can be discharged, in particular in a predetermined manner, especially into an external environment of the vehicle.

[0025] Alternatively or in addition to arranging the platinum plate in the liquid circuit as described above, the platinum plate can also be arranged, for example, in the battery, particularly within a battery housing, especially at a collection point where hydrogen formed in the battery accumulates. The operating principle is then as described above. In particular, temperature sensors and especially a warning unit can also be provided, the warning unit being specifically designed and configured to warn of hydrogen in the battery when a predetermined temperature limit is exceeded, based on the temperature of the platinum plate determined by the temperature sensor.

[0026] This solution is particularly useful when the battery's temperature control fluid uses water or a water mixture. As described above, it is specifically designed to prevent this temperature control fluid from coming into contact with the battery's live parts. If this does occur, especially due to leaks or damaged seals, there is a risk that the resulting hydrogen will not be circulated through the fluid circuit but will instead accumulate in the battery, particularly in the battery casing, and especially at a designated collection point. By placing the platinum plate there, this hydrogen can then be converted back into water in the manner described, thus preventing large accumulations of hydrogen in the battery that could lead to an explosion.Furthermore, the temperature sensor can also detect the resulting heating of the platinum plate, allowing the warning unit to issue an alert that hydrogen has formed and is present in the battery if the temperature of the platinum plate exceeds the predefined temperature limit. Maintenance and repair can then be recommended or initiated.

[0027] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing.

[0028] This shows: Fig. 1 schematically a vehicle with a device for detecting hydrogen in a liquid circuit and for removing the hydrogen from the liquid circuit.

[0029] Fig.Figure 1 shows a schematic representation of an exemplary embodiment of a vehicle 1 with a device 2 for detecting hydrogen, in particular small amounts of hydrogen, in a liquid circuit 3 of the vehicle 1 and for removing the hydrogen, in particular the small amounts of hydrogen, from this liquid circuit 3.

[0030] Vehicle 1 has a battery 7. The fluid circuit 3 is a temperature control circuit of vehicle 1, designed and configured for temperature control, in particular cooling, of battery 7. Battery 7 is, in particular, a traction battery, intended specifically for supplying electrical energy to at least one electric drive motor of vehicle 1 for propelling vehicle 1. Vehicle 1 is, in particular, an electric vehicle or a hybrid vehicle.

[0031] The device 2 has a platinum plate 4 which is arranged in the liquid circuit 3, in the illustrated example in an expansion tank 5 of the liquid circuit 3. Furthermore, the device 2 has a temperature sensor 6 which is designed and configured to measure the temperature of the platinum plate 4.

[0032] In the illustrated embodiment, the fluid circuit 3 has oil or an oil mixture as a temperature control fluid and is thermally coupled via a heat exchanger 8 of the vehicle 1 to a further fluid circuit 9 of the vehicle 1, wherein the further fluid circuit 9 has water or a water mixture as a temperature control fluid, in particular a water-containing temperature control fluid.

[0033] The temperature sensor 6 is advantageously coupled with a warning unit 10, which is in particular designed and configured to warn of hydrogen in the liquid circuit 3 when a predetermined temperature limit is exceeded by a temperature of the platinum plate 4 determined by means of the temperature sensor 6.

[0034] In particular, such a vehicle 1, which is designed as an electric vehicle or hybrid vehicle, has a high-voltage battery as battery 7, in particular a traction battery, as described above. This battery 7 must be temperature-controlled, in particular cooled, depending on the operating conditions. This is done in the manner described above, for example, with anhydrous oil or an oil mixture as the temperature control fluid. However, water can enter the temperature control fluid, which is designed as oil or an oil mixture, for example, due to leaks, aging, or otherwise damaged seals, particularly from the further fluid circuit 9 via the heat exchanger 8.

[0035] In the described example, when using oil or an oil mixture as a temperature control fluid, the current-carrying parts of battery 7 can be directly cooled and thus heated. However, this can also bring water into contact with the current-carrying parts of battery 7. This can lead to hydrogen production within battery 7, which is then transported in the liquid circuit 3 together with the temperature control fluid.

[0036] When this hydrogen, especially in small quantities, reaches the platinum plate 4, a catalytic recombination to form water, especially water vapor, occurs on this platinum plate 4, particularly even outside the ignition limits of hydrogen, especially at room temperature and with a sufficient supply of oxygen. This is also referred to as catalytic combustion or catalytic oxidation of hydrogen. The platinum of the platinum plate 4 acts as a catalyst and heats up in the process. The temperature of the platinum plate 4 is determined by the temperature sensor 6, so that this heating is detected and the hydrogen in the liquid circuit 3 is thus sensed. For example, a warning unit 10 can issue a warning that hydrogen has formed and is present in the liquid circuit 3 if the temperature of the platinum plate 4 exceeds the predefined temperature limit.For example, maintenance and repair can then be recommended or arranged.

[0037] By constantly converting the hydrogen at the platinum plate 4 to water in the manner described, an accumulation of larger quantities of hydrogen and a resulting risk of explosion are avoided.

[0038] In the illustrated example, the platinum plate 4 is arranged in an upper section 5.1 of the expansion vessel 5. This allows hydrogen contained in the temperature control fluid in the expansion vessel 5 to escape from the temperature control fluid, rise to the top, and reach the platinum plate 4.

[0039] In the illustrated example, a hydrogen-permeable and liquid-tight membrane 11 is arranged between the upper section 5.1 and a lower section 5.2 of the expansion tank 5, which has an inlet and an outlet of the liquid circuit 3. The hydrogen escaping from the temperature control fluid in the lower section 5.2 of the expansion tank 5 can thus pass through the membrane 11 into the upper section 5.1 and to the platinum plate 4. Water is produced by the platinum plate 4 and the hydrogen, whereby the hydrogen is consumed and thus removed. The liquid-tight membrane 11 prevents this water from flowing downwards into the lower section 5.2 and thus into the temperature control fluid, and / or prevents the temperature control fluid from flowing into the upper section 5.1.

[0040] The water accumulating in the upper section 5.1 of the expansion tank 5 can be drained, for example, via a drain line, for example by opening a shut-off valve, manually, for example during maintenance of the vehicle 1, or automatically, for example at a predetermined water level, or pumped out, for example during maintenance of the vehicle 1 or automatically, for example at a predetermined water level. Reference symbol list 1 vehicle 2 Device 3. Fluid Cycle 4 platinum plates 5 expansion tanks 5.1 upper section 5.2 lower section 6 Temperature sensors 7 Battery 8 heat exchangers 9 further fluid circuits 10 warning units 11 Membran

Claims

[1] Device (2) for detecting hydrogen, in particular small amounts of hydrogen, in a liquid circuit (3) and for removing the hydrogen, in particular the small amounts of hydrogen, from the liquid circuit (3), comprising - a platinum plate (4) which is arranged or can be arranged in the liquid circuit (3), and - a temperature sensor (6) designed and configured to measure the temperature of the platinum plate (4) characterized by , that the liquid circuit (3) is a temperature control circuit designed and equipped for temperature control, in particular cooling, of a battery (7) of a vehicle (1). [2] Device (2) according to claim 1, characterized by a reservoir (5) of the fluid circuit (3), wherein the platinum plate (4) is arranged in the reservoir (5). [3] Device (2) according to any one of the preceding claims, characterized by, that the platinum plate (4) is arranged in an upper section (5.1) of the expansion tank (5). [4] Device (2) according to claim 3, characterized by , that a hydrogen-permeable and liquid-tight membrane (11) is arranged between the upper section (5.1) and a lower section (5.2) of the expansion tank (5), which has an inlet and an outlet of the liquid circuit (3). [5] Device (2) according to any one of the preceding claims, characterized by , that the temperature sensor (6) is coupled with a warning unit (10) which is designed and configured to warn of hydrogen in the liquid circuit (3) when a predetermined temperature limit is exceeded by a temperature of the platinum plate (4) determined by means of the temperature sensor (6). [6] Vehicle (1) comprising a device (2) according to any of the preceding claims. [7] Vehicle (1) according to claim 6, characterized by , that the fluid circuit (3) includes oil or an oil mixture or water or a water mixture as the temperature control fluid. [8] Vehicle (1) according to claim 6 or 7, characterized by , that the liquid circuit (3) is thermally coupled via a heat exchanger (8) to another liquid circuit (9), wherein the other liquid circuit (9) contains water or a water mixture as the temperature control fluid.

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