Electrochemical device, in particular fuel cell device

Abstract

The invention relates to an electrochemical device (1), in particular a fuel cell device (10), comprising an electrochemical unit (11) designed to electrochemically react a supplied medium, and a particle filter (50) designed to filter particles from a flow (S) of the supplied medium. It is proposed to integrate the particle filter (50) at least substantially into the electrochemical unit (11).

Description

[0001] The present invention relates to an electrochemical device, in particular a fuel cell device, comprising an electrochemical unit which is intended to electrochemically convert a supplied medium, and a particle filter which is intended to filter out particles from a flow of the supplied medium. State of the art

[0002] Electrochemical devices, in particular fuel cell devices, are known which comprise an electrochemical unit or a fuel cell unit to which a medium, e.g. fuel, is supplied, wherein particles are filtered out of a flow of the medium by means of a separately arranged upstream particle filter. Disclosure of the invention

[0003] The present invention, with the features of the main claim, has the advantage that the particulate filter is at least substantially integrated into the electrochemical unit. This allows for a reduction in installation space and the variety of components.

[0004] In the context of the present invention, an "electrochemical device" can be understood in particular as a device intended to convert chemical energy into electrical 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 energy, or an electrolysis cell device, which in particular enables the conversion of electrical energy into chemical energy, preferably for storage. Accordingly, a high-temperature electrochemical device can, for example, be a high-temperature fuel cell device or a high-temperature electrolysis cell device.

[0005] The phrase “at least substantially” is to be understood in the context of the invention in particular to mean that a condition or property to which the phrase refers is present or satisfied in its basic or important aspects or characteristics, but possibly not in all details or not with perfect accuracy. In particular, the phrase indicates that, although there may be some minor tolerances, deviations, variations or imperfections, the condition or property is nevertheless present. In particular, the phrase indicates that a proximity to the condition or property has been achieved, even if it is not 100% perfect or exact. In particular, the phrase indicates that the condition or property has been achieved at least 90%, preferably at least 95%.

[0006] The features listed in the subclaims enable advantageous developments of the invention according to the main claim. Thus, it is advantageous if the electrochemical unit comprises a plurality of electrochemical cells designed to electrochemically convert the supplied medium. The electrochemical unit comprises a supply channel designed to distribute the supplied medium across the plurality of electrochemical cells. The particle filter is at least substantially incorporated into the supply channel. This enables a particularly space-saving design.

[0007] It is also advantageous if the particulate filter is cylindrical, preferably tubular. This allows the particulate filter to have a relatively large surface area despite limited installation space, which in turn allows the pressure loss at the particulate filter to be kept relatively low.

[0008] In the context of the invention, "tubular" is understood to mean, in particular, that an object has the shape of a hollow cylinder whose length is significantly greater than its diameter. A tubular object can, in particular, have a cylindrical shape with an empty interior defined by a tubular wall.

[0009] It is advantageous if the particulate filter is closed at one end. This can have a beneficial effect on the flow pattern.

[0010] It is also advantageous if the particulate filter has a stop at one end, preferably at the end opposite the closed end. This can simplify installation of the particulate filter.

[0011] It is also advantageous if the particle filter, preferably a tube wall of the particle filter, contains pores with a pore size of 50 µm to 200 µm. This allows for efficient particle filtering while simultaneously keeping pressure loss to a minimum.

[0012] In the context of the invention, “pores” are to be understood in particular as hollow or empty spaces or openings in a material or structure.

[0013] It is also advantageous if the particulate filter is at least essentially dimensionally stable. This can increase the stability of the assembly.

[0014] It is particularly advantageous if the particulate filter is made of a temperature-resistant material, preferably at least up to 650°C. This also enables application in the high-temperature range.

[0015] For the purposes of the invention, “temperature-resistant” is understood to mean, in particular, the ability of a material or substance to maintain its structural integrity, mechanical properties or functionality under certain temperature conditions without suffering significant changes, damage or decomposition.

[0016] It is also particularly advantageous if the particulate filter is at least partially made of an electrically non-conductive material and / or coated with an electrically non-conductive material. This can reduce the risk of short circuits within the electrochemical unit.

[0017] It is also advantageous if the particulate filter is arranged at a distance from the numerous electrochemical cells. This can also reduce the risk of short circuits within the electrochemical unit. Drawings

[0018] The drawings schematically illustrate embodiments of the invention and explain them in more detail in the following description. Fig. 1 is a schematic circuit diagram of an embodiment of an electrochemical device, Fig. 2 shows a schematic cross-section of a part of an electrochemical unit from Fig. 1, Fig. 3 an enlarged view of the schematic cross-section of the part of the electrochemical unit from Fig. 2. Description of the embodiments

[0019] In Fig. Figure 1 shows a schematic circuit diagram of an exemplary embodiment of an electrochemical device 1. In the exemplary embodiment shown, the electrochemical device 1 is a fuel cell device 10. Alternatively, it would also be possible for the electrochemical device 1 to be an electrolysis cell device. However, the invention will be explained in more detail using the example of the fuel cell device 10 shown, without being limited to this.

[0020] The electrochemical device 1, in this case the fuel cell device 10, comprises two electrochemical units 11 in the illustrated embodiment, in the case shown two fuel cell units 12. In the illustrated embodiment, the fuel cell units 12 are designed as fuel cell stacks 13, which have a plurality of fuel cells. In the present case, the fuel cells are solid oxide fuel cells (SOFCs). Alternatively, it would also be possible for the fuel cells to be polymer electrolyte fuel cells (PEFCs) or proton exchange membrane fuel cells (PEMFCs).

[0021] Furthermore, the fuel cell device 10 comprises a plurality of processor units 14. A "processor unit" can be understood here, in particular, as a unit or component of the fuel cell device 10 that is not a fuel cell unit 12, or a fuel cell and / or a fuel cell stack. In particular, the processor unit 14 is one for the, preferably chemical and / or thermal, pre- and / or post-processing of at least one medium to be converted and / or converted in a fuel cell unit, such as a fuel B, RB, air L, and / or an exhaust gas A, AA. A processor unit 14 is preferably a reformer 26, an afterburner 28, and / or a heat exchanger 36, 38, 44.

[0022] In the illustrated embodiment, for example, during normal operation, air L is supplied to a cathode chamber 20 of the fuel cell units 12 via an air supply 16, while reformed fuel RB, in this case hydrogen, is supplied to an anode chamber 22. In the fuel cell units 12, the reformed fuel RB is electrochemically converted with the aid of oxygen from the air L, generating electricity and heat.

[0023] The fuel cell device 10 comprises a processor unit 14, in the case shown a reformer 26. The reformer 26 is provided to convert a fuel B, in the present case natural gas containing methane (CH4), supplied to the fuel cell device 10, in the case shown via a fuel supply 24, into the reformed fuel RB, in the present case a mixture containing hydrogen (H2), for the electrochemical conversion in the fuel cell units 12.

[0024] Furthermore, the fuel cell units 12 are connected on the exhaust side to a further processor unit 14, in this case to an afterburner 28. The exhaust gases of the fuel cell units 12 are fed to the afterburner 28, in this case cathode exhaust gas KA via a cathode exhaust gas duct 30 and a portion of the anode exhaust gas AA via an anode exhaust gas duct 32. The cathode exhaust gas KA contains unused air L or unused oxygen, while the anode exhaust gas AA contains any unreacted, reformed fuel RB and / or any unreformed fuel B. By means of the afterburner 28, the anode exhaust gas AA or any unreacted, reformed fuel RB and / or any unreformed fuel B contained therein is combusted with the admixture of the cathode exhaust gas KA or the oxygen of the air L contained therein.

[0025] The hot exhaust gas A produced during combustion in the afterburner 28 is discharged from the afterburner 28 via an exhaust gas duct 34 and a further processor unit 14, in this case via a heat exchanger 36. The heat exchanger 36 is in turn fluidly connected to the reformer 26, so that heat can be transferred from the hot exhaust gas A to the fuel B supplied to the reformer 26. Accordingly, the heat of the hot exhaust gas A can be used to reform the supplied fuel B in the reformer 26.

[0026] Furthermore, another processor unit 14, in this case a further heat exchanger 38, is located in the exhaust duct 34 downstream of the heat exchanger 36. The heat exchanger 38 is in turn fluidically connected to the air supply 16, so that the remaining heat of the hot exhaust gas A can be transferred to the supplied air L in the air supply 16. Accordingly, the remaining heat of the hot exhaust gas can be used to preheat the supplied air L in the air duct 16.

[0027] Furthermore, the fuel cell device 10 has a return line 39, by means of which a portion of the anode exhaust gas AA can be diverted from the anode exhaust gas line 32 and fed to a recirculation line 42 forming a recirculation circuit 40. The diverted anode exhaust gas AA passes through a further processor unit 14, in this case a further heat exchanger 44.

[0028] By means of the recirculation circuit 40 or the recirculation line 42, the branched portion of the anode exhaust gas AA can be returned or re-supplied to the respective anode chamber 22 of the fuel cell units 12 and / or to the reformer 26, so that any unreacted, reformed fuel RB contained in the branched anode exhaust gas AA can be subsequently converted in the fuel cell unit 12 and / or any unreformed fuel B contained in the branched anode exhaust gas AA can be subsequently reformed in the reformer 26. This can further increase the efficiency of the fuel cell device 10. Furthermore, fresh fuel B can be admixed to the branched anode exhaust gas AA recirculated in the recirculation circuit 40 via the fuel supply line 24.By means of the further heat exchanger 44, heat can then be transferred from the branched anode exhaust gas AA from the return line 38 to the fuel mixture in the recirculation circuit 40 resulting from the addition of the fresh fuel B for thermal processing.

[0029] The supply of air L in the air supply 16, the supply of fuel B in the fuel supply 24 and the recirculation rate of the media in the recirculation circuit 40 can be regulated and / or coordinated with one another via compressors 46 in the respective lines.

[0030] As already explained, the electrochemical device 1, or fuel cell device 10, shown here comprises two electrochemical units 11, or fuel cell units 12, which are intended to electrochemically convert a supplied medium, in the case shown the reformed fuel RB.

[0031] The electrochemical device 1, or the fuel cell device, is characterized in that a particle filter 50 is integrated into at least one, in this case into each, of the electrochemical units 11, or fuel cell units 12, which is intended to filter out particles from a flow S of a supplied medium, in the case shown, the reformed fuel RB. Accordingly, in Fig. 2 a schematic cross-section of a part of one of the electrochemical units 11, or fuel cell units 12, from Fig. 1 shown.

[0032] By integrating the particulate filter 50 into the electrochemical unit 11 or the fuel cell unit 12, the particulate filter 50 does not need to be installed separately upstream of the electrochemical unit 11 or the fuel cell unit 12, thus saving installation space. Furthermore, the variety of parts is reduced.

[0033] In the embodiment shown, the electrochemical unit 11 or fuel cell unit 12 shown comprises - as already mentioned - a plurality of electrochemical cells 52 or fuel cells 54, which are intended to electrochemically convert the supplied medium, in this case the reformed fuel RB.

[0034] Furthermore, the electrochemical unit 11, or fuel cell unit 12, in the embodiment shown comprises a supply channel 56, which is provided to distribute the supplied medium, in this case the reformed fuel RB, over the plurality of electrochemical cells 52, or fuel cells 54.

[0035] In the embodiment shown, the particle filter 50 is now at least substantially inserted into the supply channel 56. This enables a particularly space-saving design.

[0036] In the illustrated embodiment, the particulate filter 50 is cylindrical, and in the illustrated case, tubular. This allows the particulate filter 50 to have a relatively large surface area despite the limited installation space, which in turn allows the pressure loss at the particulate filter 50 to be kept relatively low.

[0037] In the illustrated embodiment, the particulate filter 50 is designed to be closed at one end 58. This advantageously influences the flow guidance.

[0038] Furthermore, the particulate filter 50 has a stop 62 at one end 60, in this case at an end 60 opposite the closed end 58. This simplifies assembly of the particulate filter. Accordingly, Fig. 3 an enlarged view of the schematic cross-section of the part of the electrochemical unit 11, or fuel cell unit 12, from Fig. 2 shown.

[0039] In the illustrated case, the particle filter 50, in this case a tube wall 64 of the particle filter 50, comprises pores with a pore size of 50 µm to 200 µm. This allows particles to be filtered efficiently while simultaneously keeping pressure loss low.

[0040] Furthermore, in the illustrated embodiment, the particulate filter 50 is at least substantially—in this case, entirely—dimensionally stable. This can increase the stability of the assembly.

[0041] Furthermore, in the illustrated embodiment, the particulate filter 50 is made of a material that is temperature-resistant, in this case at least up to 650°C. This also enables application in the high-temperature range.

[0042] Furthermore, in the illustrated embodiment, the particulate filter 50 is at least partially, in this case entirely, made of an electrically non-conductive material. This reduces the risk of short circuits within the electrochemical unit 11 or fuel cell unit 12.

[0043] Alternatively, it would also be conceivable for the particle filter 50 to be coated with an electrically non-conductive material, which can also reduce the risk of short circuits within the electrochemical unit 11 or fuel cell unit 12.

[0044] In an alternative embodiment, which is not illustrated, it would also be possible for the particulate filter 50 to be arranged at a distance from the plurality of electrochemical cells 52 or fuel cells 54. This can also reduce the risk of short circuits within the electrochemical unit 11 or fuel cell unit 12.

Claims

[1] Electrochemical device (1), in particular fuel cell device (10), comprising an electrochemical unit (11) which is intended to electrochemically convert a supplied medium, and a particle filter (50) which is intended to filter out particles from a flow (S) of the supplied medium, characterized by that the particle filter (50) is at least substantially integrated into the electrochemical unit (11). [2] Electrochemical device (1) according to claim 1, characterized byin that the electrochemical unit (1) comprises a plurality of electrochemical cells (52) which are provided for electrochemically converting the supplied medium, wherein the electrochemical unit (11) comprises a feed channel (56) which is provided for distributing the supplied medium over the plurality of electrochemical cells (52), and wherein the particle filter (50) is at least substantially introduced into the feed channel (56). [3] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50) is cylindrical, preferably tubular. [4] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50) is closed at one end (58). [5] Electrochemical device (1) according to one of the preceding claims, characterized bythat the particle filter (50) has a stop (62) at one end (60), preferably at an end (60) opposite the closed end (58). [6] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50), preferably a tube wall (64) of the particle filter (50), comprises pores with a pore size of 50 µm to 200 µm. [7] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50) is at least substantially dimensionally stable. [8] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50) is made of a material that is temperature-resistant, preferably at least up to 650°C. [9] Electrochemical device (1) according to one of the preceding claims, characterized bythat the particle filter (50) is at least partially formed from an electrically non-conductive material and / or is coated with an electrically non-conductive material. [10] Electrochemical device (1) according to one of the preceding claims, characterized by that the particle filter (50) is arranged at a distance from the plurality of electrochemical cells (52).

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