Fuel cell generator module having fuel cell stack arrangement structure

Abstract

The invention relates to a fuel cell generator module (10) having a fuel cell stack arrangement for generating electric power. According to the invention, a supply gallery (4) is provided in the intermediate region, which extends substantially in a vertical direction (V) and a horizontal direction (H) through the fuel cell generator module (10). Furthermore, the stacking direction (S) of the stacks (1) extends horizontally through the fuel cell generator modules (10), and the stack ends (14) of the at least two stacks (1) lie opposite each other from both sides of the supply gallery (4). The flow path of the anode supply line (20) and the flow path of the cathode supply line (30) are arranged within the supply gallery (4) between the opposite stack ends (14) of the at least two stacks (1).

Description

Technical Field

[0001] The present invention relates to a fuel cell generator module for generating electricity, which has a thermodynamically optimized fuel cell stack arrangement structure. Background Art

[0002] The fuel cell generator module according to the present invention can be used as an independent device or as part of a fuel cell power generation system in the field of energy production, feeding renewable energy into the power grid or a self - sufficient island power grid.

[0003] Currently, high - performance SOFC (Solid Oxide Fuel Cell) and SOEC (Solid Oxide Electrolyzer) fuel cell systems are known in stationary applications. They are used in large - scale application scenarios such as grid feeding and operate at a relatively constant operating point or with a small power dynamic.

[0004] Solid oxide fuel cells operate at high temperatures. Due to the high temperature, there is a large temperature gradient between the fuel cell generator module and the surrounding environment, the temperature distribution is correspondingly uneven, and the distance of the fuel cell stack inside the fuel cell generator module relative to the outside has a significant impact on the dissipation of waste heat to the surrounding environment.

[0005] In addition, due to the high temperature and the temperature gradient between regions of the fuel cell generator module, optimizing the medium flow supplied to the fuel cell stack faces challenges, especially in terms of heat distribution and heat exchange between media, which all affect the overall efficiency of the fuel cell generator module.

[0006] One method of preheating fresh media is to use a heat exchanger to transfer the waste heat in the discharged medium flow to the supplied medium flow. Although the use of such components has become standard, the development of static layout schemes for system components is still ongoing. Therefore, it is necessary to optimize the relative layout between system components in the context of efficient heat distribution. Summary of the Invention

[0007] The object of the present invention is to provide a technology that can improve the thermal efficiency or overall energy efficiency of a fuel cell generator module. The specific object of the present invention is to provide a design of such a fuel cell generator module or the layout of system components therein, in a static manner, that is, by a simple and low - cost method, without adding additional system components, to more efficiently optimize the heat distribution between medium flows in the fuel cell generator module.

[0008] The above object is achieved by a fuel cell generator module having the features of claim 1. Other features and details of the present invention come from the dependent claims, the description, and the drawings.

[0009] A fuel cell generator module having a fuel cell stack arrangement structure is used to generate electricity. The fuel cell generator module includes: a plurality of fuel cells that are stacked on top of each other in a stacking direction and are electrically connected; an anode supply line that includes an anode gas supply line for supplying a combustible gas to the anode portion of the fuel cell and an anode gas discharge line for discharging anode exhaust gas therefrom; and a cathode supply line that includes a cathode gas supply line for supplying an oxidizing gas to the cathode portion of the fuel cell and a cathode gas discharge line for discharging cathode exhaust gas therefrom.

[0010] According to the present invention, the fuel cell generator module has a supply corridor in a central region, which extends through the fuel cell generator module substantially in a vertical direction and a horizontal direction. Here, these stacks are stacked one above the other, that is, the stacking direction of the stacks vertically passes through the fuel cell generator module, and the stack ends of at least two stacks face each other from both sides of the supply corridor. The plurality of stacks can be advantageously arranged or disposed side by side. These fuel cells are in particular always designed to be flat and are stacked on top of each other or stacked vertically upwards respectively. In this case, the flow paths of the anode supply line and the cathode supply line are arranged within the supply corridor in particular between the stack ends of at least two stacks facing each other.

[0011] Therefore, the present invention provides a vertical stacking arrangement of fuel cells within a fuel cell generator module, the fuel cell stack arrangement structure is separated from the center by a vertical plane (substantially a symmetry plane), and a corridor for the extension of a medium distribution mechanism is established along this separation line.

[0012] According to the present invention, control and operation functional components, that is, balance-of-plant (BoP) components, such as an air compressor, a combustible gas regulating valve, etc., are preferably arranged in the supply corridor. The BoP components are therefore in particular not arranged in the so-called "manifold" between the fuel cell stacks, but in particular exactly within the supply corridor between the stack ends of at least two stacks facing each other.

[0013] Here, the arrangement according to the present invention makes use of the fact that the waste heat generated by the internal power generation or electrochemical reaction in the fuel cell is more concentrated in the central region of the module due to the limited heat dissipation from the outer surface of the module. Therefore, during the operation of the module, a local high-temperature region is formed in the central region, and the supply corridor according to the present invention is provided in this region.

[0014] Thus, an advantage of the present invention is that the medium distribution mechanism is arranged in the central region of the fuel cell generator module, which has the highest local temperature in the thermal distribution of the entire fuel cell generator module due to the minimum waste heat dissipation through the outer side. Due to the high operating temperature of the solid oxide fuel cell (SOFC), for high thermal efficiency operation, it is beneficial to preheat the fresh supply medium flows of the combustible gas and the oxidizing gas as fully as possible before entering the fuel cell stack. Arranging the supply galleries in the central region with the highest temperature and the very short inlet path achieved through the vertical stacking direction provide the largest possible preheating effect for the fresh medium flows by means of this static arrangement. In particular, cooling of the supply path due to passing through the outer region of the module is avoided here.

[0015] Furthermore, compared with the known point-symmetric medium flow and radial stack arrangement, a further advantage of the present invention is that standard components with existing designs and basic right-angled dimensions can be used in the arrangement according to the present invention.

[0016] According to an advantageous aspect of the present invention, the plurality of fuel cells can be divided into at least four stacks, the stack ends of which are oppositely disposed facing each other on both sides of the supply gallery, wherein at least two stacks are arranged side by side in a horizontal direction orthogonal to the stacking direction. Therefore, the arrangement of the fuel cell stacks can continue to extend in a plane of the module while maintaining the thermodynamic advantage effect. The number of stack pairs on both sides of the supply gallery can be arbitrarily expanded in the horizontal direction according to the module size.

[0017] According to an advantageous aspect of the present invention, these fuel cells can be divided into at least four stacks, the stack ends of which are oppositely disposed facing each other on both sides of the supply gallery, wherein at least two stacks are stacked one above the other in a vertical direction orthogonal to the stacking direction. Therefore, the arrangement of these fuel cell stacks can also be divided into multiple levels and stacked one above the other, while the stacking direction, the orientation of the supply gallery, and its thermodynamic advantage effect remain unchanged.

[0018] According to an advantageous aspect of the present invention, the anode supply line and the cathode supply line, as well as the anode discharge line and the cathode discharge line, can be in fluid communication with the at least two stacks respectively at the stack ends facing each other. Thereby, the possibly lower temperature inlet path between the supply gallery and the stacks is minimized.

[0019] According to an advantageous aspect of the present invention, the cathode discharge line can leave the fuel cell generator module in a substantially vertical direction in the supply gallery. Thus, the buoyancy of the high-temperature exhaust gas towards the outlet is utilized hydrodynamically.

[0020] According to an advantageous aspect of the present invention, the cathode exhaust line of a stack can pass through an oxidation catalytic converter for the oxidative reprocessing of cathode exhaust gas, wherein the oxidation catalytic converter is arranged in the supply corridor. Since the oxidation catalytic converter needs to reach and maintain a predetermined minimum operating temperature, arranging it in the locally high-temperature area of the supply corridor helps to more effectively regulate the temperature of the medium flow through mutual heat exchange.

[0021] Accordingly, according to an advantageous aspect of the present invention, at least two opposed stacks can pass through the same oxidation catalytic converter. By sharing system components in the adjacent stack arrangement structure, further efficiency improvement, simplification, and space and cost savings are achieved.

[0022] According to an advantageous aspect of the present invention, the anode exhaust line of a stack can lead into a reformer device for enriching the unreacted combustible gas portion in the anode exhaust gas with fresh combustible gas, wherein the reformer device is arranged in the supply corridor. Since the reformer device also needs to reach and maintain a predetermined minimum operating temperature, arranging it in the locally high-temperature area of the supply corridor helps to more effectively regulate the temperature of the medium flow through mutual heat exchange. For this purpose, a circulation section is particularly provided, which includes a circulation line for returning at least a part of the anode exhaust gas to the anode section. The circulation line is supplied with fresh combustible gas, so that a mixture containing anode exhaust gas and fresh combustible gas is supplied to the anode section in particular.

[0023] Accordingly, according to an advantageous aspect of the present invention, the anode exhaust lines of at least two opposed stacks can pass through the same reformer device. By sharing system components in the adjacent stack arrangement structure, efficiency improvement, simplification, and space and cost savings are achieved again.

[0024] According to an advantageous aspect of the present invention, the anode gas supply line and the cathode gas supply line can enter the fuel cell generator module in a substantially horizontal direction. This makes the flow path of the medium supply device as long as possible in the locally high-temperature area of the supply corridor, thus helping to more effectively regulate the temperature of the medium flow through maximum mutual heat exchange.

[0025] According to an advantageous aspect of the present invention, an oxidation gas heat exchanger can be provided between the cathode exhaust line and the cathode supply line of the same stack, located in the supply corridor. The oxidation gas heat exchanger is arranged in the locally high-temperature area of the supply corridor, improving the thermal efficiency during the preheating of fresh oxidation gas.

[0026] According to an advantageous aspect of the present invention, a combustible gas heat exchanger can be provided between the anode exhaust line and the anode supply line of the same stack, located in the supply corridor. The combustible gas heat exchanger is arranged in the locally high-temperature area of the supply corridor, also improving the thermal efficiency during the preheating of combustible gas.

[0027] According to an advantageous aspect of the present invention, the anode gas supply line can pass through a preheating device, which is arranged in the supply corridor and upstream of the combustible gas heat exchanger. The preheating device is arranged in the locally high-temperature area of the supply corridor, further improving the thermal efficiency during the preheating of the combustible gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other advantages, features and details of the present invention result from the following description of embodiments in detail with reference to the drawings, in which:

[0029] Figure 1 is a schematic top view block diagram of a fuel cell generator module according to an embodiment of the present invention, in which the temperature distribution is also shown,

[0030] Figure 2 is a partial perspective view of the system components of a fuel cell generator module according to an embodiment of the present invention,

[0031] Figure 3 is a partial perspective view of the system components and pipeline network of a fuel cell generator module according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Figure 1 is a top view schematic diagram of the fuel cell generator module 10, in which ten stacks 1 (A - J) are arranged on the bottom surface, divided into two opposed groups (A - E) and (F - J), wherein each stack 1 within each group is adjacent to each other in the horizontal direction (V). Stacks 1 with the same configuration are also located in the layers not further shown above and below the fuel cell generator module 10. The fuel cells are stacked along the horizontal stacking direction S, in other words, from the shown top view, the stacks 1 are laid flat.

[0033] The fuel cell generator module 10 can be used alone as an independent device for power generation, or it can also be used as a unit in a fuel cell generator system environment not further shown, the system having a plurality of electrically connected fuel cell generator modules 10.

[0034] As shown by the hatching, the outermost regions near the outer surface in the fuel cell generator module 10 are colder as they are exposed to the colder ambient temperature. The outer regions contribute to the dissipation of waste heat from the fuel cells in the stacks 1, thus forming a temperature gradient from the inside to the outside. In the middle region of the fuel cell generator module 10, since it is not directly exposed to the outer surface, the dissipation of waste heat from the fuel cells is correspondingly less, and thus there is a higher local temperature.

[0035] In this locally high-temperature area, a supply corridor 4 is provided, which is parallel to the two opposing groups (A-E) and (F-J) of the stack 1, forming a plane extending in the horizontal and vertical directions therebetween. The flow paths of the medium distribution mechanism are arranged in the supply corridor 4 through the anode supply pipeline 20 and the cathode supply pipeline 30. In addition, control and operation functional components not further shown, namely the Balance of Plant (BoP) components such as air compressors, combustible gas regulating valves, etc., are also provided in the supply corridor 4.

[0036] According to the power scale and fail-safe requirements of the fuel cell generator module 10, the anode supply pipeline 20, the cathode supply pipeline 30, and the BoP components can be provided individually or redundantly for each layer of the fuel cell generator module 10, or shared by all layers, that is, commonly used through the pipeline network of the stack 1 connected to different layers of the fuel cell generator module 10.

[0037] Figure 2 The layout of all system components in the fuel cell generator module 10 through which the medium distribution mechanism flows is schematically shown in a perspective view, and these components are related to regulating the temperature of the medium flow through heat exchange and exhaust gas treatment.

[0038] Therefore, at the left and right sides of the supply corridor 4, the mutually facing stack ends 14 of two opposing stacks 1 are representatively shown. The system components in the supply corridor 4 mentioned for regulating the temperature of the medium distribution mechanism include: an oxidation heat exchanger 34 for preheating the incoming air through the cathode exhaust gas flow, an oxidation catalytic converter 33 for oxidizing the hydrogen concentration in the cathode exhaust gas flowing out of the pressure tank, and the symbolically shown anode exhaust gas circulation device 26, which includes a preheating device 25 for preheating the fresh combustible gas and a reformer device 23 for mixing and enriching the unreacted combustible gas portion in the anode exhaust gas with the fresh combustible gas.

[0039] Except for the two combustible gas heat exchangers 24 arranged adjacent to the supply corridor 4, all the above-mentioned system components are arranged in the temperature zone of the supply corridor 4, so as to further heat the supply corridor 4 through the waste heat of the exhaust gas absorbed from the fuel cell to maintain its own working temperature, or obtain heat through the concentrated waste heat of the stack 1 to preheat the freshly supplied medium.

[0040] Figure 3 Shown from another perspective Figure 2The structure includes a pipeline network of an anode supply pipeline 20 and a cathode supply pipeline 30. The anode gas supply pipeline 21 and the cathode gas supply pipeline 31 are used to supply fresh or low-temperature combustible gas and oxidizing gas. They horizontally pass through the supply corridor so as to be preheated in advance through pipeline heat exchange as much as possible. The cathode gas discharge pipeline 32 vertically passes through the oxidation catalytic converter 33 and the oxidation gas heat exchanger 34 from the outlet of the stack end 14. The latter preheats the freshly supplied air before it enters the stack end 14. The cathode waste gas discharged from the stack end 14 flows through the reformer unit 23 and heats the freshly supplied combustible gas through the preheating device 25 and the combustible gas heat exchanger 24 before entering the stack end 14.

[0041] The system components for temperature regulation of the medium distribution mechanism shown by taking one stack 1 or stack end 14 as an example are equally applicable to a plurality of adjacent stacks 1 which are adjacent in the vertical direction and arranged in multiple layers up and down. In particular, it is stipulated that two superimposed stacks 1 are commonly connected to the same heat exchange component on both sides of the supply corridor 4 or share its function.

[0042] The description of the above embodiments only describes the present invention within the scope of examples. Obviously, as long as the various features of the embodiments are technically meaningful, they can be freely combined with each other without exceeding the scope of the present invention.

[0043] List of reference numerals

[0044] 1 Fuel cell stack

[0045] 4 Supply corridor

[0046] 10 Fuel cell generator module

[0047] 14 Stack end

[0048] 20 Anode supply pipeline

[0049] 21 Anode gas supply pipeline

[0050] 22 Anode gas discharge pipeline

[0051] 23 Reformer device

[0052] 24 Combustible gas heat exchanger

[0053] 25 Preheating device

[0054] 26 Anode gas circulation device

[0055] 30 Cathode supply pipeline

[0056] 31 Cathode gas supply pipeline

[0057] 32 Cathode gas discharge pipeline

[0058] 33 Oxidation Catalyst

[0059] 34 Oxidation Gas Heat Exchanger

[0060] H Horizontal Direction

[0061] V Vertical Direction

[0062] S Stacking Direction

Claims

1. A fuel cell generator module (10) having a fuel cell stack arrangement for generating electric power, the fuel cell generator module comprising: - A plurality of fuel cells stacked one above the other in a stack (1) in a stacking direction (S) and electrically connected; - An anode supply line (20) including an anode gas supply line (21) for supplying a combustible gas to an anode portion of the fuel cell and an anode gas discharge line (22) for discharging anode exhaust gas therefrom; - A cathode supply line (30) including a cathode gas supply line (31) for supplying an oxidizing gas to a cathode portion of the fuel cell and a cathode gas discharge line (32) for discharging cathode exhaust gas therefrom; Characterized in that the fuel cell generator module (10) has a supply corridor (4) in an intermediate region, the supply corridor extending substantially in a vertical direction (V) and a horizontal direction (H) through the fuel cell generator module (10), and the stacking direction (S) of the stack (1) extends horizontally through the fuel cell generator module (10), and stack ends (14) of at least two stacks (1) face each other from both sides of the supply corridor (4), wherein flow paths of the anode supply line (20) and the cathode supply line (30) are arranged within the supply corridor (4) between the stack ends (14) of the at least two stacks (1) facing each other.

2. The fuel cell generator module (10) according to claim 1, wherein, These fuel cells are divided into at least four stacks (1) whose stack ends (14) face each other from both sides of the supply corridor (4), wherein at least two stacks (1) are arranged side by side in a horizontal direction (H) orthogonal to the stacking direction (S).

3. The fuel cell generator module (10) according to claim 1 or 2, wherein, These fuel cells are divided into at least four stacks (1) whose stack ends (14) face each other from both sides of the supply corridor (4), and at least two stacks (1) are arranged one above the other in a vertical direction (V) orthogonal to the stacking direction (S).

4. The fuel cell generator module (10) according to one of the preceding claims, wherein, The anode supply line and the cathode supply line and the anode discharge line and the cathode discharge line are in fluid communication with the at least two stacks (1) respectively at the stack ends (14) facing each other.

5. The fuel cell generator module (10) according to one of the preceding claims, wherein, The cathode discharge line leaves the fuel cell generator module (10) in a substantially vertical direction (V) in the supply corridor (4).

6. The fuel cell generator module (10) according to one of the preceding claims, wherein, The cathode discharge line of one stack (1) passes through an oxidation catalytic converter (33) for oxidative reprocessing of the cathode exhaust gas, wherein the oxidation catalytic converter (33) is arranged within the supply corridor (4).

7. The fuel cell generator module (10) according to one of the preceding claims, wherein, The cathode discharge lines of at least two opposing stacks (1) pass through the same oxidation catalytic converter (33).

8. The fuel cell generator module (10) according to one of the preceding claims, wherein, The anode discharge line of one stack (1) leads to a reformer device (23) for enriching the anode exhaust gas with fresh combustible gas, wherein the reformer device (23) is arranged within the supply corridor (4).

9. The fuel cell generator module (10) according to claim 8, wherein, The anode discharge lines of at least two opposing stacks (1) pass through the same reformer device (23).

10. The fuel cell generator module (10) according to one of the preceding claims, wherein, The anode gas supply line (21) and the cathode gas supply line (31) enter the fuel cell generator module (10) in a substantially horizontal direction (H).

11. The fuel cell generator module (10) according to one of the preceding claims, wherein, An oxidizing gas heat exchanger (34) is provided between the cathode discharge line and the cathode supply line of the same stack (1), and is located within the supply gallery (4).

12. A fuel cell generator module (10) according to one of the preceding claims, wherein, A combustible gas heat exchanger (24) is provided between the anode discharge line and the anode supply line of the same stack (1), and is located within the supply gallery (4).

13. The fuel cell generator module (10) according to one of the preceding claims, wherein, The anode gas supply line (21) passes through a preheating device (25), which is arranged within the supply gallery (4) and upstream of the combustible gas heat exchanger (24).

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