Method for operating an electrochemical device, as well as an electrochemical device operated by such a method

Abstract

The invention relates to a method for operating an electrochemical device (10), and to an electrochemical device (10) operated by such a method, comprising an electrochemical unit (12). It is proposed to define an actual temperature (T Stack,Out,Act ) of a medium discharged from the electrochemical unit (12) at least substantially to a target temperature (T Stack,Out,Set ) for the medium discharged from the electrochemical unit (12), wherein the actual temperature (T Stack,Out,Act ) by measuring an actual temperature (T Stack,Anode,Out,Act ) of a medium (M3) discharged from the anode side of the electrochemical unit is to be determined.

Description

[0001] The present invention relates to a method for operating an electrochemical device, as well as an electrochemical device comprising an electrochemical unit. State of the art

[0002] Methods for operating electrochemical devices comprising an electrochemical unit are known. Disclosure of the invention

[0003] In contrast, the present method for operating an electrochemical device with the features of the main claim has the advantage that the actual temperature of a medium discharged by the electrochemical unit is adjusted, at least substantially, to a target temperature for the medium discharged by the electrochemical unit, wherein the actual temperature is determined by measuring the actual temperature of a medium discharged from the anode side of the electrochemical unit. This allows the efficiency of the electrochemical device to be specifically increased.

[0004] Advantageous embodiments of the invention according to the main claim are possible through the features listed in the dependent claims. For example, it is advantageous if the target temperature for the medium discharged from the electrochemical unit, preferably on the anode side, corresponds to a difference between a predetermined, in particular specified, preferably maximum, temperature value and a compensation value, wherein the compensation value is determined, in particular fixed. This enables a simplified increase in the efficiency of the electrochemical device.

[0005] It is also advantageous if the target temperature for the medium discharged from the electrochemical unit, preferably on the anode side, and in particular the compensation value, is not dynamically adjusted. This further simplifies increasing efficiency.

[0006] It is also advantageous if the target temperature for the medium discharged from the electrochemical unit, preferably on the anode side, and in particular the compensation value, is determined and especially fixed once. This greatly simplifies the process of increasing efficiency.

[0007] It is advantageous if the target temperature for the medium discharged from the electrochemical unit, preferably on the anode side, and in particular the compensation value, is determined, preferably once, by means of a temperature loss measurement, particularly on the anode and / or cathode side, especially between a temperature that is substantially at its maximum within the electrochemical unit and a temperature that is at the anode-side outlet of the electrochemical unit. This enables a particularly reliable increase in efficiency.

[0008] It is also advantageous if the target temperature for the medium supplied to the electrochemical unit, preferably on the anode side, is determined, preferably once, during operation of the electrochemical device or before commissioning the electrochemical device. This simplifies the operation of the electrochemical device.

[0009] The present electrochemical device has the advantage that it is operated using a method as described above. This allows the efficiency of the electrochemical device to be increased.

[0010] Within the scope of the present invention, an "electrochemical device" can be understood to mean, in particular, a device designed to convert chemical energy into electrical and / or thermal energy, or vice versa. An electrochemical device can, for example, be a fuel cell device, which in particular enables the conversion of a fuel, e.g., hydrogen, into electrical and / or thermal energy, or an electrolysis cell device, which in particular enables the conversion of electrical energy into chemical energy, preferably for storage. Preferably, the electrochemical device comprises one or more electrochemical units.

[0011] Within the scope of the present invention, an "electrochemical unit" can be understood to mean, in particular, a unit comprising a plurality of electrochemical cells. If the electrochemical cells are fuel cells, the electrochemical unit can, in particular, be a fuel cell unit. If the electrochemical cells are electrolysis cells, the electrochemical unit can be an electrolysis cell unit. Preferably, the electrochemical unit can be an electrochemical cell stack in which the plurality of electrochemical cells are stacked on top of one another. If the electrochemical cells are fuel cells, the electrochemical cell stack can, in particular, be a fuel cell stack.If the electrochemical cells are electrolysis cells, then the electrochemical cell stack can in particular be an electrolysis cell stack (English: Electrolyser Cell Stack).

[0012] Within the scope of the present invention, an "electrochemical cell" can be understood to mean, in particular, a cell designed to convert chemical energy into electrical energy or vice versa. An electrochemical cell can, for example, be a fuel cell, which in particular enables the conversion of a fuel, e.g., hydrogen, into electrical and / or thermal energy, or an electrolysis cell, which in particular enables the conversion of electrical energy into chemical energy, preferably for storage. In the case of a fuel cell, it can, for example, be designed as a solid oxide fuel cell (SOFC), a proton exchange membrane fuel cell (PEMFC), or an anion exchange membrane fuel cell (AEMFC).In the case of an electrolysis cell, it can be designed, for example, as a solid oxide electrolyzer cell (SOEC), a proton exchange membrane electrolyzer cell (PEMEC), or an anion exchange membrane electrolyzer cell (AEMEC).

[0013] Within the scope of the present invention, an “actual temperature” can be understood in particular as an actually prevailing temperature, which can be determined, for example, by means of a measurement, preferably direct, in particular by means of a sensor.

[0014] Within the scope of the present invention, a “target temperature” can be understood in particular as a temperature value that can be determined, for example, by a mathematical and / or experimental analysis, preferably an indirect one.

[0015] In the context of the present invention, the phrase "at least substantially" can be understood to mean, in particular, that a condition or property to which the phrase refers is present or fulfilled in its fundamental or important aspects or characteristics, but possibly not in all details or with perfect accuracy. Specifically, the phrase indicates that, although there may be some minor tolerances, deviations, variations, or imperfections, the condition or property is nevertheless present. Specifically, the phrase indicates that a close approximation to the condition or property has been achieved, even if it is not 100% perfect or exact. Specifically, the phrase indicates that the condition or property can be achieved to at least 90%, preferably at least 95%. Drawings The single figure shows a schematic representation of an exemplary embodiment of an electrochemical device. Description of the exemplary implementations

[0016] The single figure shows a schematic representation of an embodiment of an electrochemical device 10. The electrochemical device 10 comprises an electrochemical unit 12. The electrochemical unit 12 comprises an electrochemical cell stack 14, which in turn comprises a plurality of electrochemical cells.

[0017] In the illustrated embodiment, the electrochemical device 10 is a fuel cell device 16 and the electrochemical unit 12 is a fuel cell unit 18. Accordingly, the fuel cell device 16 comprises the fuel cell unit 18.

[0018] In the case shown, the fuel cell unit 18 is an electrochemical unit 12, comprising a fuel cell stack 20, which in turn comprises a plurality of fuel cells.

[0019] In the case shown, the fuel cells are solid oxide fuel cells (SOFCs). Alternatively, they could also be proton exchange membrane fuel cells (PEMFCs) or anion exchange membrane fuel cells (AEMFCs).

[0020] In an alternative embodiment, the electrochemical device 10 could also be an electrolysis cell device, and the electrochemical unit 12 could be an electrolysis cell unit. Accordingly, the electrolysis cell device would then comprise the electrolysis cell unit. Alternatively, in the case of an electrolysis cell device, the electrolysis cell unit could comprise an electrolysis cell stack, which in turn comprises a plurality of electrolysis cells, for example, proton exchange membrane electrolyzer cells (PEMECs) or anion exchange membrane electrolyzer cells (AEMECs).

[0021] In the illustrated embodiment, a first medium M1 is supplied to a first electrode compartment 22 of the electrochemical unit 12 via a first media supply 24, and a second medium M2 is supplied to a second electrode compartment 26 via a second media supply 28. In the electrochemical unit 12, the first medium M1 is then electrochemically reacted with the participation of the second medium M2.

[0022] In the illustrated case of the fuel cell unit 18 as electrochemical unit 12, the first electrode compartment 22 is an anode compartment 30 and the second electrode compartment 22 is a cathode compartment 32. Furthermore, in the illustrated case of the fuel cell unit 18 as electrochemical unit 12, the first medium supplied, M1, is fuel containing a reducing agent, in this case hydrogen, and the second medium supplied, M2, is air containing an oxidizing agent, in this case oxygen. Thus, in the case of the fuel cell unit 18 as electrochemical unit 12, the fuel is supplied to the anode side, i.e., the anode compartment 30, while air is supplied to the cathode side, i.e., the cathode compartment 32. The hydrogen contained in the fuel is then electrochemically reacted with the oxygen contained in the air.

[0023] Subsequently, in the illustrated embodiment, a third medium M3 is removed from the first electrode compartment 22, in this case the anode compartment 30, via a first media outlet 34, and a fourth medium M4 is removed from the first electrode compartment 22, in this case the cathode compartment 32, via a second media outlet 36 from the electrochemical unit 12.

[0024] In the case of the fuel cell unit 18 as electrochemical unit 12, the third medium M3 is an exhaust gas discharged from the anode compartment 30, in this case an anode exhaust gas, which contains at least some of a product formed during the electrochemical reaction in the anode compartment 30. In contrast, in the case of the fuel cell unit 18 as electrochemical unit 12, the medium M4 is an exhaust gas discharged from the cathode compartment 32, in this case a cathode exhaust gas, which contains at least some unused air or oxygen.

[0025] In the illustrated embodiment, the first media discharge 34 leads via a first heat exchanger 38, which is in thermal exchange with the first media supply 24, and via a second heat exchanger 40, which is in thermal exchange with the second media supply 28. Thus, during operation of the electrochemical device 10, thermal energy generated during the electrochemical reaction of the fuel contained in the first medium M1 can be transferred to preheat the media M1 and M2 yet to be supplied.

[0026] In the illustrated embodiment, a first compressor 42 regulates the quantity of the first medium M1, in this case fuel, supplied to the electrochemical unit 12 (anode side in this case). A second compressor 44, in turn, regulates the quantity of the second medium M2, in this case air, supplied to the electrochemical unit 12 (cathode side in this case).

[0027] The thermal energy generated during the electrochemical reaction in the electrochemical unit 12 is at least partially transferred to the media flowing through the electrochemical unit 12. Thus, the media discharged from the electrochemical unit 12, in this case the third medium M3 and the fourth medium M4, exhibit a higher level of thermal energy than the media supplied to the electrochemical unit 12, in this case the first medium M1 and the second medium M2. Accordingly, a temperature gradient ΔT prevails at the electrochemical unit 12 during operation of the electrochemical device 10.

[0028] The temperature gradient ΔT, on the cathode side in the case shown, corresponds to a difference between an actual temperature (T) Stack,Out,Act ) of the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, and an actual temperature (TStack,In,Act ) of the medium supplied to the electrochemical unit 12, in this case on the cathode side, here the second medium M2. Accordingly, the temperature gradient ΔT, in this case on the cathode side, can be set by adjusting the actual temperature (T Stack,In,Act ) of the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, and / or the actual temperature (T Stack,Out,Act ) of the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, are adjusted.

[0029] In the illustrated embodiment, the electrochemical device 10 comprises a bypass 46, which is designed to divert a portion of the medium M2 supplied to the electrochemical device 10 from the second media supply 28 upstream of the second heat exchanger 40 and return it to the second media supply 28 downstream of the second heat exchanger 40. In the illustrated case, the quantity of the portion of the second medium M2 diverted by the bypass 46 can be controlled by a three-way valve 48, which is controllable in this case. This ensures that the portion of the second medium M2 diverted by the bypass 46 does not flow through the second heat exchanger 40 and is therefore not preheated.

[0030] By mixing the unheated portion of the second medium M2, which in the case shown is diverted through bypass 48 downstream of the second heat exchanger 40, with the preheated portion of the second medium M2, which in the case shown is passed through the second heat exchanger 40, the actual temperature (T) can then be adjusted. Stack,In,Act The temperature of the medium supplied to the electrochemical unit 12, in this case the cathode side, namely the second medium M2, can be influenced. Accordingly, in the case shown, the actual temperature (T) can be controlled by regulating the amount of the portion of the second medium M2 diverted through bypass 46. Stack,In,Act ) of the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, is regulated or adjusted.

[0031] The actual temperature (T) can be determined by the total amount of medium supplied to the electrochemical unit 12, in this case the cathode side, in this case the second medium M2. Stack,Out,Act ) of the medium discharged by the electrochemical unit 12, in this case on the cathode side, here the fourth medium M4. Accordingly, in the case shown, the actual temperature (T) can be influenced by regulating the total quantity of the medium, here the second medium M2, supplied by the compressor 44 of the electrochemical unit 12, in this case on the cathode side. Stack,Out,Act ) of the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, is regulated or adjusted.

[0032] In the illustrated embodiment, the electrochemical device 10 is operated in such a way that the prevailing temperature gradient ΔT does not leave a predetermined temperature range, specified in the illustrated case, thereby preventing damage in and / or to the electrochemical unit 12.

[0033] The temperature range corresponds to a range between a predetermined, specified minimum temperature value T. Cell,In and a predetermined, specified maximum temperature value T Cell,Out .

[0034] Accordingly, in the illustrated embodiment, the actual temperature T Stack,In,Act of the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, and the actual temperature T Stack,Out,Actof the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, is set such that the specified minimum temperature value T is reached. Cell,In not undercut and the specified maximum temperature value T Cell,Out is not exceeded.

[0035] Furthermore, the electrochemical device 10 shown is operated in such a way that the temperature gradient ΔT prevailing at the electrochemical unit 12, in this case on the cathode side, is increased, particularly within the specified temperature range. By increasing the temperature gradient ΔT, the volume flow rate of the medium supplied to the electrochemical unit 12, in this case on the cathode side, namely the second medium M2, can be kept essentially constant or only slightly increased. This, in turn, allows the power consumption of the first compressor 44 to be kept essentially constant or only slightly increased. Ultimately, this increases the overall efficiency of the electrochemical device 10.

[0036] In the illustrated embodiment, the temperature gradient ΔT can be dynamically increased within the specified temperature range. This allows the volumetric flow rate of the medium supplied to the electrochemical unit 12 (in this case, the cathode side), in this instance the second medium M2, to be flexibly increased during operation of the electrochemical device 10. Consequently, the efficiency of the electrochemical device 10 can be flexibly increased during operation.

[0037] In the case shown, the dynamic increase of the temperature gradient ΔT can occur at regular time intervals. Alternatively, it would also be possible for the dynamic adjustment of the temperature gradient ΔT to occur continuously.

[0038] In the case shown, the temperature gradient ΔT can be increased within the specified temperature range depending on the service life of the electrochemical unit 12. This allows the volume flow rate of the medium supplied to the electrochemical unit 12, preferably on the cathode side (in this case, the second medium M2), and thus the power consumption of the blower, to be adjusted in such a way as to counteract power losses of the electrochemical unit that may accompany a longer service life. This, in turn, allows the efficiency of the electrochemical device 10 to be maintained at a high level.

[0039] In this case, the temperature gradient ΔT within the specified temperature range can be adjusted as a function of a state parameter, in particular a degradation parameter, preferably of a component, of the electrochemical unit. Thus, the volume flow rate of the medium supplied to the electrochemical unit 12 (in this case, the cathode side), in this instance the second medium M2, and consequently the power consumption of the first compressor 44, can be adjusted in such a way as to counteract power losses of the electrochemical unit 12 caused by a change of state, for example, by degradation of components, within the electrochemical unit 12 over its lifetime. This allows the efficiency of the electrochemical device 10 to be maintained at a particularly high level.

[0040] The increase of the temperature gradient ΔT, particularly within the specified temperature range, can be achieved, for example, by the methods described in more detail below.

[0041] In a first embodiment, the electrochemical device 10 shown can be operated such that the temperature gradient ΔT within the specified temperature range is at least reduced to the specified minimum temperature value T. Cell,In This increases the efficiency of the electrochemical device.

[0042] In this first embodiment, the temperature gradient (ΔT) can be adjusted within the specified temperature range, preferably at least towards the specified minimum temperature value T. Cell,InThe volume flow rate of the medium supplied to the electrochemical unit 12 (in this case, the second medium M2) – in this instance, the second medium M2 – and thus the power consumption of the compressor 44, can be adjusted as a function of a degradation parameter of a reformer component within the electrochemical unit 12. This allows for targeted counteracting of power losses in the electrochemical unit 12 caused by degradation of a reformer component within the electrochemical unit 12 over its lifetime. This results in a particularly advantageous increase in efficiency.

[0043] The temperature gradient ΔT can be adjusted or increased in this first version by specifying an actual temperature T. Stack,In,Act one of the electrochemical units 12, in the case shown cathode-side, supplied medium, in this case second medium M2, at least substantially to a target temperature TStack,In,Set The temperature of the medium supplied to the electrochemical unit, in this case the cathode side (second medium M2), is adjusted, in particular reduced. Thus, the temperature gradient ΔT can be reduced to the specified minimum temperature value T. Cell,In This can be specifically regulated. This also enables a particularly advantageous increase in efficiency.

[0044] In the illustrated embodiment of the electrochemical device 10, the actual temperature (T) can be used for this purpose. Stack,In,Act ) of the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case second medium M2, by means of a sensor 50, in this case arranged in the second medium supply 28.

[0045] In the first version mentioned, the target temperature T can be Stack,In,Setfor the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case second medium M2, a sum of the specified, in particular specified, minimum temperature value T Cell,In and a compensation value T Offset,In correspond to the compensation value T Offset,In This can be determined. This makes it possible to determine the target temperature T. Stack,In,Set , in particular the compensation value T Offset,In , to determine via a mathematical and / or experimental analysis, whereby the setting or regulation of the actual temperature T Stack,In,Act to the target temperature T Stack,In,Set This can be done more easily. This, in turn, allows for a simplified adjustment of the temperature gradient ΔT, in this case towards the specified minimum temperature value T. Cell,In This enables a simplified increase in efficiency.

[0046] The target temperature T Stack,In,Setfor the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case medium M2, in particular the compensation value T Offset,In In the first version, the target temperature (T) can be adjusted dynamically, preferably continuously or at regular intervals. Stack,In,Set , in particular the compensation value T Offset,In , also to be determined dynamically via a mathematical and / or experimental analysis, thereby enabling dynamic adjustment or control of the actual temperature T Stack,In,Act to the target temperature T Stack,In,Set This can be done more easily. Accordingly, the efficiency of the electrochemical device 10 can be simplified and flexibly increased during its operation.

[0047] In the first version mentioned, the target temperature T can be Stack,In,Setfor the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, in particular the compensation value T Offset,In , depending on a state parameter, in particular a component, of the electrochemical unit 12. Thus, a change in state, which is caused, for example, by degradation of components within the electrochemical unit 12 over its lifetime, can be adjusted when adjusting the target temperature T. Stack,In,Set for the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, in particular the compensation value T Offset,In , must be taken into account. Accordingly, the efficiency of the electrochemical device 10 can be simplified and efficiently maintained at a high level.

[0048] The target temperature T Stack,In,Setfor the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, in particular the compensation value T Offset,In In the aforementioned first embodiment, the temperature T can be adjusted depending on a degradation parameter of a reformer component of the electrochemical unit. Thus, a specific change of state, caused particularly by degradation of the reformer component of the electrochemical unit 12 over its lifetime, can be accounted for when adjusting the target temperature T. Stack,In,Set for the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, in particular the compensation value T Offset,In , must be taken into account. Accordingly, the efficiency of the electrochemical device 10 can be simplified and maintained at a particularly high level of efficiency.

[0049] In the first version mentioned, the target temperature T can beStack,In,Set for the medium supplied to the electrochemical unit 12, in the case shown on the cathode side, in this case the second medium M2, in particular the compensation value T Offset,In , is determined from a comparison, in particular of the state parameter, preferably the degradation parameter, with an existing data set, in particular a characteristic curve, stored in a control unit 56. The existing data set, or the characteristic curve, can be determined from an experimental analysis, preferably a single measurement, and / or a mathematical analysis, for example a simulation. Thus, the setting or control of the actual temperature T can be achieved. Stack,In,Act to the target temperature T Stack,In,Set This can be done in a particularly simplified way. This, in turn, allows the efficiency of the electrochemical device 10 to be particularly simplified and efficiently maintained at a high level.

[0050] In a second embodiment, the electrochemical device 10 shown can be operated such that the temperature gradient ΔT within the specified temperature range at least approaches the specified maximum temperature value T. Cell,Out This increases the efficiency of the electrochemical device 10.

[0051] In this second embodiment, the temperature gradient ΔT can be adjusted within the specified temperature range, preferably at least towards the specified maximum temperature value T. Cell,Out, depending on a degradation parameter of a functional layer component of the electrochemical unit 12. Thus, the volume flow rate of the medium supplied to the electrochemical unit 12, in this case the second medium M2, and consequently the power consumption of the compressor 44, can be adjusted in such a way as to specifically counteract power losses of the electrochemical unit 12 caused by degradation of a functional layer within the electrochemical unit 12 over its lifetime. This also enables a particularly advantageous increase in the efficiency of the electrochemical device 10.

[0052] The temperature gradient ΔT can be increased in the second embodiment mentioned above by setting an actual temperature T. Stack,Out,Actof the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, at least essentially to a target temperature T Stack,Out,Set The temperature gradient ΔT of the medium discharged from the electrochemical unit 12, in this case from the cathode side (medium M4), is adjusted, in particular increased. Thus, the temperature gradient ΔT can be reduced to the specified maximum temperature value T. Cell,Out can be specifically controlled. This also enables a particularly advantageous increase in the efficiency of the electrochemical device 10.

[0053] In the illustrated embodiment of the electrochemical device 10, the actual temperature T can be used for this purpose. Stack,Out,Actthe medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case fourth medium M4, is measured by means of a sensor 52, in this case arranged in the second medium discharge 36.

[0054] The target temperature T Stack,Out,Set For the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, here the fourth medium M4, in the aforementioned second embodiment a difference between the specified maximum temperature value T can be observed. Cell,Out and a compensation value T Offset,Out correspond to the compensation value T Offset,Out This can be determined. This makes it possible to determine the target temperature T. Stack,Out,Set , in particular the compensation value T Offset,Out , to determine via a mathematical and / or experimental analysis, whereby the setting or regulation of the actual temperature T Stack,Out,Act to the target temperature T Stack,Out,SetThis can be done more easily. This, in turn, allows for a simplified adjustment of the temperature gradient ΔT, in this case towards the specified maximum temperature value T. Cell,Out This enables a simplified increase in efficiency.

[0055] In the second version mentioned, the target temperature T can be Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,Out , dynamically, preferably continuously or at regular intervals, adjusted. This makes it possible to adjust the target temperature T. Stack,Out,Set , in particular the compensation value T Offset,Out , also to be determined dynamically via a mathematical and / or experimental analysis, thereby enabling dynamic adjustment or control of the actual temperature T Stack,Out,Act to the target temperature T Stack,Out,SetThis can be done more easily. Accordingly, the efficiency of the electrochemical device can be simplified and flexibly increased during operation.

[0056] The target temperature T Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,Out In the second embodiment mentioned, the temperature can be adjusted depending on a state parameter, in particular a component, of the electrochemical unit 12. Thus, a change in state, caused, for example, by component degradation within the electrochemical unit 12 over its lifetime, can be compensated for by adjusting the target temperature T. Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,Out, must be taken into account. Accordingly, the efficiency of the electrochemical device 10 can be simplified and efficiently maintained at a high level.

[0057] In the second version mentioned, the target temperature T can be Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,Out , depending on a degradation parameter of a functional layer component of the electrochemical unit 12 and / or a reformer component of the electrochemical unit 12. In this way, a specific change of state, caused specifically by degradation of the functional layer component and / or the reformer component of the electrochemical unit 12 over its lifetime, can be adjusted when adjusting the target temperature T. Stack,Out,Setfor the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,Out , must be taken into account. Accordingly, the efficiency of the electrochemical device 10 can be simplified and maintained at a particularly high level of efficiency.

[0058] The target temperature T Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the cathode side, in this case the fourth medium M4, in particular the compensation value T Offset,OutIn the second embodiment mentioned, the temperature T can be determined by comparing, in particular, the state parameter, preferably the degradation parameter, with an existing data set, in particular a characteristic curve, stored in the control unit 56. The existing data set, or characteristic curve, can be determined from an experimental analysis, preferably a single measurement, and / or a mathematical analysis, for example, a simulation. This allows for the setting or control of the actual temperature T. Stack,Out,Act to the target temperature T Stack,Out,Set This can be done in a particularly simplified way. This, in turn, allows the efficiency of the electrochemical device 10 to be particularly simplified and efficiently maintained at a high level.

[0059] In a third embodiment, the electrochemical device 10 shown can be operated such that an actual temperature T Stack,Out,Actof a medium discharged from the electrochemical unit 12 at least substantially to a target temperature value T Stack,Out,Set for the medium discharged by the electrochemical unit 12, whereby the actual temperature T Stack,Out,Act by measuring an actual temperature T Stack,Anode,Out,Act The temperature of a medium discharged from the anode side of electrochemical unit 12, in this case the third medium M3, is determined by measuring the actual temperature T. Stack,Anode,Out,Act of the medium discharged from the anode side of the electrochemical unit 12, in this case the third medium M3, the influence of temperature losses, such as those that occur during a measurement of the actual temperature T, can be Stack,Cathode,Out,Act The potential for fluctuations in the medium discharged from the cathode side of electrochemical unit 12 can be reduced. This, in turn, allows for more precise control of the actual temperature T. Stack,Out,Actof the medium discharged from the electrochemical unit 12, and thus a more targeted increase of the temperature gradient ΔT is possible. Accordingly, the efficiency of the electrochemical device 10 can be specifically increased.

[0060] In the illustrated embodiment of the electrochemical device 10, the actual temperature T can be used for this purpose. Stack,Anode,Out,Act the medium discharged from the electrochemical unit 12, in the case shown on the anode side, in this case the third medium M3, is measured by means of a sensor 54, in this case arranged in the first medium discharge 34.

[0061] In this third version, the target temperature T can be set. Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the anode side, here the third medium M3, a difference between a predetermined, here specified, maximum temperature value T Cell,Out and a compensation value T Offset,Outcorrespond to the compensation value T Offset,Out This allows the target temperature T to be determined, and in particular, set. Stack,Out,Set to determine, via a mathematical and / or experimental analysis, the setting or regulation of the actual temperature T Stack,Out,Act to the target temperature T Stack,Out,Set This can be done more easily. In addition to more precise control of the actual temperature T, this also allows for... Stack,Out,Act also a simpler control of the actual temperature T Stack,Out,Act This enables a simplified increase in efficiency.

[0062] In the third version mentioned, the target temperature T can be Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the anode side, in this case the third medium M3, in particular the compensation value T Offset,Out , cannot be dynamically adjusted. Thus, the determination of the target temperature T cannot be Stack,Out,SetThis can be simplified. In turn, this can further simplify increasing efficiency.

[0063] The target temperature T Stack,Out,Set for the medium discharged from the electrochemical unit 12, preferably on the anode side, in this case the third medium M3, in particular the compensation value T Offset,Out , can be determined once in the aforementioned third version, in particular, it can be specified.

[0064] Furthermore, the target temperature T can be Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the anode side, in this case the third medium M3, in particular the compensation value T Offset,OutIn the third embodiment mentioned above, the target temperature T can be determined, preferably once, by measuring a temperature loss, particularly between a substantially maximum temperature prevailing in the electrochemical unit 12 and a temperature prevailing at the anode-side outlet of the electrochemical unit 12, especially on the anode and / or cathode side. Stack,Out,Set , in the present case of the compensation value T Offset,Out This process is particularly reliable. Accordingly, it also enables a particularly reliable increase in efficiency.

[0065] The target temperature T Stack,Out,Set for the medium discharged from the electrochemical unit 12, in the case shown on the anode side, in this case the third medium M4, in particular the compensation value T Offset,OutIn the aforementioned third embodiment, the target temperature T can be determined, preferably once, during the operation of the electrochemical device 10 or before commissioning the electrochemical device 10. This allows for the determination of the target temperature value T, particularly on a one-off basis. Stack,Out,Set , in the present case of the compensation value T Offset,Out This can occur, for example, during the start-up phase of the electrochemical device, during assembly of the electrochemical device, or during factory settings. This simplifies the operation of the electrochemical device.

[0066] In a further, alternative embodiment, it is possible for the electrochemical device 10 shown to be operated with a combination of the first, second, and / or third embodiments described above. This would enable a particularly significant increase in the efficiency of the electrochemical device 10.

[0067] Within the framework of this further, alternative embodiment, it would also be possible for the electrochemical device 10 shown to be operated in such a way that the temperature gradient ΔT within the specified temperature range according to the first embodiment described above, in particular dynamically, approaches the specified minimum temperature value T. Cell,In , and according to the second embodiment described above, in particular dynamically, towards the specified maximum temperature value T. Cell,Out is increased.

[0068] In this further, alternative embodiment, it would also be possible for the electrochemical device 10 shown to be operated in such a way that the temperature gradient ΔT within the specified temperature range, as described above in the first embodiment, is increased, in particular dynamically, towards the specified minimum temperature value T. Cell,In , is increased and, according to the third execution described above, the actual temperature T Stack,Out,Act of a medium discharged from the electrochemical unit 12 at least substantially to a target temperature value T Stack,Out,Set for the medium discharged by the electrochemical unit 12, whereby the actual temperature T Stack,Out,Act by measuring an actual temperature T Stack,Anode,Out,Act a medium, in this case third medium M3, is determined from the anode side of the electrochemical unit 12.

[0069] Likewise, within the framework of this further, alternative embodiment, it would be possible for the electrochemical device 10 shown to be operated in such a way that the temperature gradient ΔT within the specified temperature range according to the first embodiment described above, in particular dynamically, decreases towards the specified minimum temperature value T. Cell,In , and according to the second embodiment described above, in particular dynamically, towards the specified maximum temperature value T. Cell,Out is increased, whereby, according to the third version described above, the actual temperature T Stack,Out,Act of a medium discharged from the electrochemical unit 12 at least substantially to a target temperature value T Stack,Out,Set for the medium discharged by the electrochemical unit 12, whereby the actual temperature T Stack,Out,Actby measuring an actual temperature T Stack,Anode,Out,Act a medium, in this case third medium M3, is determined from the anode side of the electrochemical unit 12.

Claims

[1] Method for operating an electrochemical device (10) comprising an electrochemical unit (12), characterized by that an actual temperature (T Stack,Out,Act ) of a medium discharged from the electrochemical unit (12) at least substantially to a target temperature (T Stack,Out,Set ) for the medium discharged by the electrochemical unit (12), where the actual temperature (T Stack,Out,Act ) by measuring an actual temperature (T Stack,Anode,Out,Act ) of a medium (M3) discharged from the anode side of the electrochemical unit. [2] Method according to claim 1, characterized by that the target temperature (T Stack,Out,Set ) for the medium (M3) discharged from the electrochemical unit (12), preferably on the anode side, a difference between a predetermined, in particular specified, preferably maximum, temperature value (T Cell,Out ) and a compensation value (T Offset,Out ) corresponds to the compensation value (TOffset,Out ) is determined, in particular established. [3] Method according to any one of the preceding claims, characterized by that the target temperature (T Stack,Out,Set ) for the medium (M3) discharged from the electrochemical unit (12), preferably on the anode side, in particular the compensation value (T Offset,Out ), is not dynamically adjusted. [4] Method according to any one of the preceding claims, characterized by that the target temperature (T Stack,Out,Set ) for the medium (M3) discharged from the electrochemical unit (12), preferably on the anode side, in particular the compensation value (T Offset,Out ), determined once, in particular set. [5] Method according to any one of the preceding claims, characterized by that the target temperature (T Stack,Out,Set ) for the medium (M3) discharged from the electrochemical unit (12), preferably on the anode side, in particular the compensation value (T Offset,Out), preferably once, by means of a measurement of a temperature loss, in particular between a temperature prevailing substantially at its maximum in the electrochemical unit (12) and a temperature prevailing at the anode-side outlet of the electrochemical unit (12), in particular on the anode-side and / or cathode-side. [6] Method according to any one of the preceding claims, characterized by that the target temperature (T Stack,Out,Set ) for the medium (M3) discharged from the electrochemical unit (12), preferably on the anode side, preferably once, during the operation of the electrochemical device (10) or before commissioning the electrochemical device (10). [7] Electrochemical device (10) operated by a method according to one of the preceding claims.

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