AT527431B1 - Cell stack system for a fuel cell system - Google Patents

Abstract

The present invention relates to a cell stack system (100) for a fuel cell system, comprising a plurality of cell stacks (110, 112), wherein each cell stack (110, 112) has an anode section (120) and a cathode section (130), wherein the plurality of cell stacks (110, 112) have at least one edge cell stack (112), and wherein the at least one edge cell stack (112) is arranged relative to the plurality of cell stacks (110, 112) such that no cell stack (100, 112) of the plurality of cell stacks (110, 112) is arranged on one side of the edge cell stack (112), a pipe system (50) for supplying anode feed gas (AZG) and cathode feed gas (KZG) to the cell stacks (110, 112) and for discharging anode exhaust gas (AAG) and Cathode exhaust gas (KAG) from the cell stacks (110, 112), a distribution system (10) per cell stack (110, 112), each distribution system (10) fluidly connecting the anode section (120) and the cathode section (130) of the corresponding cell stack (110, 112) to the pipe system (50), and a thermal insulation device (70) for thermally insulating the at least one edge cell stack (112) against heat losses, the thermal insulation device (70) comprising a thermal insulation plate (74), the thermal insulation device (70) comprising a thermal insulation line (72) arranged in the thermal insulation plate (74), the thermal insulation line (72) being fluidly connected to the pipe system (50) for conducting cathode feed gas (KZG) through the thermal insulation plate (74).

Description

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Description

Cell stack system for a fuel cell system

[0001] The present invention relates to a cell stack system for a fuel cell system and in particular to a cell stack system with a thermal insulation device and to an arrangement with a plurality of such cell stack systems.

[0002] Cell stack systems for a fuel cell system are known in the prior art. Such cell stack systems comprise multiple cell stacks. If the cell stacks are arranged radially, then there is no edge cell stack. In contrast, with a linear or rectangular arrangement of the cell stacks, there is at least one edge cell stack, and one side of the at least one edge cell stack is exposed. This exposed side of the edge cell stack causes a concentration of heat loss at the edge cell stack. Heat loss at the edge cell stack can represent an individual disadvantage for the edge cell stack compared to the other cell stacks, in that the heat loss can lead to differences in performance and possibly to increased degradation.

[0003] Cell stack systems Cell stack systems for a fuel cell system with a thermal insulation device are known, for example, from WO 2011114972 A2, WO 2016044835 A1 and WO 2014177336 A.

[0004] Against this background, it is an object of the present invention to at least partially remedy the disadvantages described above. In particular, the object of the present invention is to provide a cell stack system in which the increased heat losses at the edge cell stack of the cell stack system can be prevented.

[0005] The above objects are achieved by a cell stack system having the features of claim 1 and an arrangement having the features of claim 11. Further features and details of the invention emerge from the subclaims, the description, and the drawings. Features and details described in connection with the cell stack system according to the invention naturally also apply in connection with the arrangement according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0006] Accordingly, a cell stack system for a fuel cell system is provided, comprising a plurality of cell stacks, each cell stack having an anode section and a cathode section, the plurality of cell stacks having at least one edge cell stack, and the at least one edge cell stack being arranged relative to the plurality of cell stacks such that no cell stack of the plurality of cell stacks is arranged on one side of the edge cell stack, a piping system for supplying anode feed gas and cathode feed gas to the cell stacks and for discharging anode exhaust gas and cathode exhaust gas from the cell stacks, a distribution system per cell stack, each distribution system fluidly connecting the anode section and the cathode section of the corresponding cell stack to the piping system, and a thermal insulation device for thermally insulating the at least one edge cell stack against heat losses.

[0007] By thermally insulating at least one edge cell stack, increased heat losses of the edge cell stack compared to the other cell stacks can be prevented. By preventing heat losses in the edge cell stack, performance differences compared to the other cell stacks can be avoided. Furthermore, increased degradation of the edge cell stack compared to the other cell stacks can be prevented.

[0008] On one side of the edge cell stack, no cell stack of the plurality of cell stacks is arranged. Accordingly, the edge cell stack is located at an edge of the plurality of

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Cell stacks. Specifically, the cell stacks are arranged in a row, with the edge cell stack located at the edge of the row. The multiple cell stacks can also be arranged in two rows. In this case, the edge cell stack is located at the edge of one of the two rows.

[0009] The thermal insulation device is arranged, in particular, on the side of the edge cell stack on which no adjacent cell stacks are arranged. Accordingly, the thermal insulation device is arranged on the exposed side of the edge cell stack, i.e., on the side on which no further cell stacks of the plurality of cell stacks are located. In principle, the thermal insulation device provides a thermal substitute for a missing adjacent cell stack.

[0010] The thermal insulation device can be a thermal insulation layer through which a fluid flows to increase the insulation temperature. This significantly increases the thermal insulation efficiency compared to an equally thick insulation layer when supplied with heat that is not dissipated into the environment by the cell stack system. Alternatively, the thermal insulation device could also be electrically operated.

[0011] In the present application, a fuel cell system is understood to mean a system (e.g., SOFC: Solid Oxide Fuel Cell) that has fuel cells for generating electrical energy using a fuel, or a system (e.g., SOEC: Solid Oxide Electrolyzer Cell) that has electrolysis cells for generating a fuel using electrical energy. A cell stack therefore comprises multiple fuel cells or multiple electrolysis cells.

[0012] The anode section of the cell stack supplies all cells (fuel cells or electrolysis cells) with anode feed gas and discharges anode exhaust gas from all cells (fuel cells or electrolysis cells).

[0013] The cathode section of the cell stack supplies all cells (fuel cells or electrolysis cells) with cathode feed gas and discharges cathode exhaust gas from all cells (fuel cells or electrolysis cells).

[0014] According to the invention, the thermal insulation device comprises a thermal insulation plate. The thermal insulation plate preferably has a suitable shape to protect the edge cell stack over a large area from excessive heat loss.

[0015] According to the invention, the thermal insulation device further comprises a thermal insulation line arranged in the thermal insulation panel. The thermal insulation line is preferably arranged in the thermal insulation panel such that the thermal insulation panel is heated evenly. This allows the thermal insulation panel to also provide uniform thermal insulation to the edge cell stack. Alternatively, the thermal insulation line can be arranged in the thermal insulation panel such that different areas of the thermal insulation panel are heated differently. In this way, the thermal insulation panel can provide varying degrees of thermal insulation to the edge cell stack at different locations.

[0016] In particular, the thermal insulation line can be arranged in a meandering pattern (i.e., in loops) within the thermal insulation panel. The thermal insulation line can also be arranged in a spiral pattern within the thermal insulation panel.

[0017] According to the invention, the thermal insulation line is fluidly connected to the pipe system for conducting cathode feed gas through the thermal insulation plate. Alternatively, the thermal insulation line can also be fluidly connected to the pipe system for conducting cathode exhaust gas through the thermal insulation plate. Advantageously, the cathode exhaust gas is already heated when it leaves the cell stack.

[0018] In principle, it can be provided that the cell stack system has a thermal insulation device distribution system, wherein the thermal insulation device distribution system comprises a supply section for supplying cathode exhaust gas to the thermal insulation line and a discharge section for discharging exhaust gas from the thermal insulation line.

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The cathode exhaust gas is routed from a cathode discharge pipe of the pipe system via the supply section to the thermal insulation line. The exhaust gas is then routed from the thermal insulation line via the discharge section back to the cathode discharge pipe.

[0019] According to a further embodiment, the cathode supply gas is used for conducting through the thermal insulation line. The thermal insulation device distribution system comprises a supply section for supplying cathode supply gas to the thermal insulation line and a discharge section for discharging exhaust gas from the thermal insulation line. In particular, the cathode supply gas is conducted from a cathode supply pipe of the pipe system via the supply section to the thermal insulation line. Furthermore, the exhaust gas is conducted from the thermal insulation line back to the cathode supply pipe via the discharge section.

[0020] According to a further embodiment of the cell stack system, the pipe system comprises at least one anode supply pipe, at least one cathode supply pipe, at least one anode discharge pipe and at least one cathode discharge pipe, wherein each distribution system comprises an anode supply section for supplying anode supply gas from the anode supply pipe to the anode section, an anode discharge section for discharging anode exhaust gas from the anode section to the anode discharge pipe, a cathode supply section for supplying cathode supply gas from the cathode supply pipe to the cathode section and a cathode discharge section for discharging cathode exhaust gas from the cathode section to the cathode discharge pipe.

[0021] Accordingly, the pipe system comprises four or more pipes. The pipe system can also be fluidly connected to cell stacks arranged in two rows. In this case, the pipe system can, in particular, comprise two anode feed pipes or two cathode feed pipes.

[0022] According to a further embodiment of the cell stack system, the pipe system extends in a longitudinal direction. "The pipe system extends in a longitudinal direction" means that the pipe system preferably extends along a straight line. Alternatively, the longitudinal direction can also have one or more bends. With a pipe system extending in the longitudinal direction, the number of cell stacks can be increased particularly easily.

[0023] In particular, the cell stacks are all arranged one behind the other along the longitudinal direction. Alternatively, the cell stacks are arranged one behind the other in two adjacent rows along the longitudinal direction.

[0024] According to a further embodiment of the cell stack system, the thermal insulation device is in mechanical contact with the at least one edge cell stack. Advantageously, good thermal insulation of the at least one edge cell stack can be achieved with direct mechanical contact between the thermal insulation device and the at least one edge cell stack.

[0025] According to a further embodiment of the cell stack system, the thermal insulation device is spaced apart from the at least one edge cell stack. In this case, heat conduction between the thermal insulation device and the edge cell stack occurs via a heat-conducting element. This heat-conducting element can also be air. There is no direct mechanical contact between the thermal insulation device and the edge cell stack.

[0026] According to a further embodiment of the cell stack system, the cell stack system comprises a further thermal insulation device for thermally insulating a further edge cell stack, wherein the at least one edge cell stack and the further edge cell stack are arranged on opposite sides of the cell stack system. Advantageously, in a linear arrangement of the plurality of cell stacks, the two edge cell stacks can then be thermally insulated at the two opposite edges of the linear arrangement.

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[0027] According to a further embodiment of the cell stack system, the plurality of cell stacks are arranged in two parallel rows. Because the plurality of cell stacks are arranged in two parallel rows, the cell stack system can be easily expanded by increasing the number of cell stacks in the two rows. One pipe system is sufficient for the fluid supply and fluid removal of the two rows of cell stacks.

[0028] According to a further embodiment of the cell stack system, the cell stack system has an edge cell stack in each of the two parallel rows. Both edge cell stacks are thermally insulated with the thermal insulation device. Advantageously, only one thermal insulation device is then required for two edge cell stacks.

[0029] The cell stack system can also have an edge cell stack at the other end of each of the two parallel rows. Both additional edge cell stacks can be thermally insulated with an additional thermal insulation device.

[0030] According to a further embodiment of the cell stack system, the cell stack system has an edge cell stack in each of the two parallel rows. Furthermore, the cell stack system has an additional thermal insulation device. The two edge cell stacks are each separately thermally insulated with one of the two thermal insulation devices. Advantageously, each of the two edge cell stacks can then be individually thermally insulated.

[0031] The cell stack system can also have an edge cell stack at the other end of each of the two parallel rows. Both additional edge cell stacks can be individually thermally insulated with two additional thermal insulation devices.

[0032] Furthermore, an arrangement comprising a plurality of cell stack systems, as described, is provided. Two cell stack systems are always connected to a pipe system via their distribution systems in a fluid-communicating manner. Furthermore, the pipe systems are connected to at least one distribution station in a fluid-communicating manner. The arrangement serves the purpose of combining the cell stack systems into an even larger unit.

[0033] In this arrangement, two cell stack systems are always connected to a common piping system. These common piping systems converge in one or more distribution stations. The distribution stations thus combine the inflows to the cell stack systems and the outflows from the cell stack systems.

[0034] According to one embodiment of the arrangement, two cell stack systems are always connected to a pipe system in a fluid-communicating manner by means of at least one thermal insulation device distribution system. The thermal insulation device distribution system then comprises the connections of both cell stack systems. Alternatively, a separate thermal insulation device distribution system can be provided for each cell stack. In the case of longitudinally extending cell stacks, the thermal insulation device distribution systems can be provided at the front and rear of the cell stack systems.

[0035] Further advantages, features, and details of the invention will become apparent from the following description, in which embodiments are described in detail with reference to the drawings. They show:

[0036] Fig. 1 is a schematic view of a cell stack system; [0037] Fig. 2 is a sectional view of the cell stack system of Fig. 1 along the line II-II;

[0038] Fig. 3 is a sectional view of the cell stack system of Fig. 1 along the line III-II1; and

[0039] Fig. 4 is a perspective view of an arrangement. [0040] Fig. 1 shows a schematic view of a cell stack system 100. The cell stack system

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tem 100 can be used as part of a fuel cell system.

[0041] The cell stack system 100 comprises a plurality of cell stacks 110, a piping system 50, a distribution system 10 per cell stack 110, and a thermal insulation device 70. Each cell stack comprises an anode section 120 and a cathode section 130. The piping system 50 serves to supply anode feed gas AZG and cathode feed gas KZG to the cell stacks 110 and to discharge anode exhaust gas AAG and cathode exhaust gas KAG from the cell stacks 110. Each distribution system 10 fluidly connects the anode section 120 and the cathode section 130 of the corresponding cell stack 110 to the piping system 50.

[0042] The multiple cell stacks 110 shown in Fig. 1 have two edge cell stacks 112. The two edge cell stacks 112 are located at the two edges of the multiple cell stacks. The two edge cell stacks 112 are arranged relative to the other cell stacks 110 such that no further cell stack 100 is arranged on either side of the edge cell stacks 112.

[0043] Figure 1 shows a thermal insulation device 70. The thermal insulation device 70 serves to thermally insulate the adjacent edge cell stack 112. This prevents heat loss in the edge cell stack 112. This prevents performance differences in the edge cell stack 112 compared to the other cell stacks 110. Furthermore, increased degradation of the edge cell stack 112 compared to the other cell stacks 110 can be prevented. As shown in Figure 1, the thermal insulation device 70 has a thermal insulation plate 74.

[0044] The thermal insulation device 70 is spaced apart from the edge cell stack 112. As shown in Fig. 1, there is no direct mechanical contact between the thermal insulation device 70 and the edge cell stack 112. Heat transfer occurs via the air. Instead of the air, a heat-conducting element can also be provided.

[0045] Alternatively, the thermal insulation device 70 can be in mechanical contact with the edge cell stack 112. This can ensure good thermal insulation.

[0046] As shown in Fig. 1, the pipe system 50 extends in a longitudinal direction 52 from a pipe system beginning 46 to a pipe system end 48. With such a course of the pipe system 50, the number of cell stacks 110 of the cell stack system 100 can be easily increased without having to make major changes to the cell stack system 100.

[0047] The cell stack system 100 shown in Fig. 1 has only one thermal insulation device 70. Alternatively, the cell stack system 100 may have a further thermal insulation device 70 for thermally insulating the second edge cell stack 112.

[0048] Fig. 2 shows a non-protective schematic sectional view of the cell stack system 100 of Fig. 1 along the line II-II. Shown are the thermal insulation device 70, the thermal insulation device distribution system 80, and the cathode exhaust pipe 68. The thermal insulation device 70 comprises the thermal insulation plate 74 and the thermal insulation line 72, wherein the thermal insulation line 72 is arranged in the thermal insulation plate 74. The thermal insulation line 72 is fluidly connected to the pipe system 50. Accordingly, in this non-protective embodiment, cathode exhaust gas KAG can be passed through the thermal insulation line 72 to heat the thermal insulation plate 74.

[0049] The thermal insulation device distribution system 80 has a supply section 82 and a discharge section 84. By means of the supply section 82, cathode exhaust gas KAG can be conducted from the cathode discharge pipe 68 to the thermal insulation line 72. By means of the discharge section 84, exhaust gas AG can be conducted from the thermal insulation line 72 to the cathode discharge pipe 68.

[0050] The cathode exhaust gas KAG is already heated by the cell stacks 110, 112, and proper-

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It is therefore well suited for heating the thermal insulation plate 74. However, according to the invention, the cathode supply gas KZG is used instead of the cathode exhaust gas KAG. In this case, the cathode supply gas KZG is conducted from the cathode supply pipe 64 to the thermal insulation line 72 by means of a supply section. Exhaust gas AG is then conducted from the thermal insulation line 72 to the cathode supply pipe 64 by means of a discharge section.

[0051] Fig. 3 shows a sectional view of the cell stack system 100 of Fig. 1 along the line I-II. Shown are the distribution system 10 with several sections 122, 124, 132, 134 and the pipe system 50 with several pipes 62, 64, 66, 68. The pipe system 50 has an anode supply pipe 62, a cathode supply pipe 64, an anode discharge pipe 66 and a cathode discharge pipe 68. The distribution system 10 has an anode supply section 122 for supplying anode supply gas AZG from the anode supply pipe 62 to the anode section 120, an anode discharge section 124 for discharging anode exhaust gas AAG from the anode section 120 to the anode discharge pipe 66, a cathode supply section 132 for supplying cathode supply gas KZG from the cathode supply pipe 64 to the cathode section 130, and a cathode discharge section 134 for discharging cathode exhaust gas KAG from the cathode section 130 to the cathode discharge pipe 68.

[0052] Fig. 4 shows a perspective view of an arrangement 200. The arrangement 200 comprises eight cell stack systems 100. Two cell stack systems 100 are each connected to a pipe system 50 in a fluid-communicating manner by means of their distribution systems 10. Two cell stack systems 100 each have the same pipe system 50. The four pipe systems 50 are connected to a distribution station 210 in a fluid-communicating manner. Alternatively, the arrangement 200 may also comprise more or fewer cell stack systems 100 or pipe systems 50. In particular, the arrangement 200 may comprise a plurality of distribution stations 210.

[0053] Two cell stack systems 100 are each connected to a pipe system 50 in fluid communication by means of a thermal insulation device distribution system 80. Accordingly, two thermal insulation devices 70 are connected to a thermal insulation device distribution system 80 in fluid communication. The thermal insulation device distribution system 80 has the corresponding supply sections 82 and discharge sections 84. Alternatively, each cell stack system 100 can also have a separate thermal insulation device distribution system 80.

[0054] As shown in Fig. 4, the cell stacks 110, 112 in the cell stack systems 100 are arranged in two parallel rows 30, 32. The eight cell stack systems 100 shown thus have a first row 30 of cell stacks 110, 112 and a second row 32 of cell stacks 110, 112.

[0055] As can be seen in Fig. 4, each cell stack system 100 has four edge cell stacks 112. The two outer edge cell stacks 112 are thermally insulated with a respective common thermal insulation device 70. Alternatively or additionally, the two inner edge cell stacks 112 can also be thermally insulated with a respective common thermal insulation device 70. In a further alternative, all respective edge cell stacks 112 can also be individually thermally insulated using a respective separate thermal insulation device 70 for each edge cell stack 112.

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LIST OF REFERENCE SYMBOLS

10 distribution system 30 first row

32 second row

46 Pipe system start 48 Pipe system end 50 Pipe system

52 Longitudinal direction

62 Anode feed pipe

64 Cathode feed pipe 66 Anode discharge pipe 68 Cathode discharge pipe

70 Thermal insulation device

72 Thermal insulation pipe

74 thermal insulation board

80 Thermal insulation device distribution system

82 feeder section

84 discharge section

100 cell stack system

110 cell stacks

112 edge cell stacks

120 anode section

122 Anode supply section 124 Anode discharge section 130 Cathode section

132 Cathode supply section 134 Cathode discharge section 200 Arrangement

210 distribution station

AZG anode feed gas

AAG anode exhaust gas

KZG cathode feed gas

KAG cathode exhaust gas

AG Exhaust

Claims (12)

x bes AT 527431 B1 2025-08-15 Ss N patent claims 1. Cell stack system (100) for a fuel cell system, comprising a plurality of cell stacks (110, 112), each cell stack (110, 112) having an anode section (120) and a cathode section (130), the plurality of cell stacks (110, 112) having at least one edge cell stack (112), and the at least one edge cell stack (112) being arranged relative to the plurality of cell stacks (110, 112) such that no cell stack (100, 112) of the plurality of cell stacks (110, 112) is arranged on one side of the edge cell stack (112), a pipe system (50) for supplying anode feed gas (AZG) and cathode feed gas (KZG) to the cell stacks (110, 112) and for discharging anode exhaust gas (AAG) and cathode exhaust gas (KAG) from the cell stacks (110, 112), a distribution system (10) per cell stack (110, 112), each distribution system (10) fluidly connecting the anode section (120) and the cathode section (130) of the corresponding cell stack (110, 112) to the pipe system (50), wherein a thermal insulation device (70) for thermally insulating the at least one edge cell stack (112) against heat losses, wherein the thermal insulation device (70) comprises a thermal insulation plate (74), characterized in that the thermal insulation device (70) has a thermal insulation line (72) which is arranged in the thermal insulation plate (74), wherein the thermal insulation line (72) is connected in a fluid-communicating manner to the pipe system (50) for conducting cathode feed gas (KZG) through the thermal insulation plate (74). 2. Cell stack system (100) according to claim 1, characterized in that the cell stack system (100) has a thermal insulation device distribution system (80), wherein the thermal insulation device distribution system (80) comprises a supply section (82) for supplying cathode exhaust gas (KAG) to the thermal insulation line (72) and a discharge section (84) for discharging exhaust gas (AG) from the thermal insulation line (72). 3. Cell stack system (100) according to one of the preceding claims, characterized in that the pipe system (50) has at least one anode feed pipe (62), at least one cathode feed pipe (64), at least one anode discharge pipe (66) and at least one cathode discharge pipe (68), wherein each distribution system (10) has an anode feed section (122) for feeding anode feed gas (AZG) from the anode feed pipe (62) to the anode section (120), an anode discharge section (124) for discharging anode exhaust gas (AAG) from the anode section (120) to the anode discharge pipe (66), a cathode feed section (132) for feeding cathode feed gas (KZG) from the cathode feed pipe (64) to the cathode section (130) and a cathode discharge section (134) for discharging cathode exhaust gas (KAG) from the cathode section (130) to the cathode discharge pipe (68). 4. Cell stack system (100) according to one of the preceding claims, characterized in that the pipe system (50) extends in a longitudinal direction (52). 5. Cell stack system (100) according to one of the preceding claims, characterized in that the thermal insulation device (70) is in mechanical contact with the at least one edge cell stack (112). 6. Cell stack system (100) according to one of claims 1 to 4, characterized in that the thermal insulation device (70) is spaced from the at least one edge cell stack (112). 7. Cell stack system (100) according to one of the preceding claims, characterized in that the cell stack system (100) has a further thermal insulation device (70) for thermally insulating a further edge cell stack (112), wherein the at least one edge cell stack (112) and the further edge cell stack (112) are arranged on opposite sides of the cell stack system (100). 8. Cell stack system (100) according to one of the preceding claims, characterized in that the plurality of cell stacks (110, 112) are arranged in two rows (30, 32) running parallel to one another. 9. Cell stack system (100) according to claim 8, characterized in that the cell stack system (100) has an edge cell stack (112) in each of the two parallel rows, and that both edge cell stacks (112) are thermally insulated with the thermal insulation device (70). 10. Cell stack system (100) according to claim 8, characterized in that the cell stack system (100) has an edge cell stack (112) in each of the two parallel rows, that the cell stack system (100) has a further thermal insulation device (70), and that the two edge cell stacks (112) are each separately thermally insulated with one of the two thermal insulation devices (70). 11. Arrangement (200) comprising a plurality of cell stack systems (100) according to one of the preceding claims, characterized in that two cell stack systems (100) are always connected to a pipe system (50) in a fluid-communicating manner by means of their distribution systems (10), and wherein the pipe systems (50) are connected to at least one distribution station (210) in a fluid-communicating manner. 12. Arrangement (200) according to claim 2 and claim 11, characterized in that two cell stack systems (100) are always connected to a pipe system (50) in a fluid-communicating manner by means of at least one thermal insulation device distribution system (80). 3 sheets of drawings