Solid oxide fuel cell intake preheating structure and cell

Abstract

The invention relates to a solid oxide fuel cell intake preheating structure, which comprises: a first shell, one end of which is provided with a first gas inlet and a second gas inlet; the second shell is coaxially arranged in the first shell at intervals, a third gas inlet is formed in the end, away from the first gas inlet, of the second shell, a combustor assembly and an electric pile assembly are sequentially arranged in the second shell in the axial direction, and the combustor assembly communicates with the electric pile assembly through a pipeline; and the heat exchange assembly is arranged in the second shell, one end of the heat exchange assembly communicates with the third gas inlet and the second gas inlet, and the other end of the heat exchange assembly communicates with the electric pile assembly. In order to solve the problems that the temperature of fuel in the system is overhigh due to reforming reaction, and the temperature of air is low due to insufficient heat exchange of an interlayer, a simple heat exchange assembly is additionally arranged on the inner side of a hot area, so that the condition of the overhigh temperature of the reforming reaction is reduced, and meanwhile, the air is further heated by heat to ensure that the temperature of the air is reduced before entering a galvanic pile. The temperature of air and fuel is controlled within a certain temperature difference range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of solid oxide fuel cells, in particular to a solid oxide fuel cell gas inlet preheating structure and a cell. BACKGROUND

[0002] Solid oxide fuel cells (SOFC) have broad application prospects in distributed power generation, mobile power supply and other fields due to their high energy conversion efficiency and strong fuel adaptability. However, SOFC normal operation needs to be carried out in a high temperature environment (usually 600-800℃), and the requirements for gas preheating and temperature control are extremely strict. On the one hand, air and fuel need to be preheated to meet the inlet temperature to ensure efficient electrochemical reaction; on the other hand, the inlet temperatures of the fuel side and the air side need to be maintained within a reasonable temperature difference range to avoid excessive temperature difference leading to thermal stress imbalance of the cell material, thereby reducing the performance of the cell or causing structural damage. In recent years, with the development of portable power supply, unmanned aerial vehicle power supply, mobile emergency power supply and other application scenarios, the market demand for lightweight, fast start and high power density SOFC systems is increasing. In conventional SOFC systems, components such as finned heat exchangers and insulation layers need to be integrated, which has the following problems: the finned heat exchanger is usually composed of multiple layers of metal fins and a shell, which is bulky, and the insulation material such as ceramic fiber is thick, resulting in expansion of the equipment volume, which is difficult to meet the demand for lightweight and miniaturization of portable mobile power supply. SUMMARY

[0003] The embodiments of the present application provide a solid oxide fuel cell gas inlet preheating structure to solve the problem that the conventional SOFC system in the related art adopts a bulky finned heat exchanger and an excessively thick insulation material, resulting in large equipment volume and heavy weight, which is difficult to meet the demand for lightweight and miniaturization in application scenarios such as portable mobile power supply.

[0004] In a first aspect, a solid oxide fuel cell gas inlet preheating structure is provided, comprising: a first shell having a first gas inlet and a second gas inlet at one end; a second shell coaxially and spacedly arranged in the first shell, having a third gas inlet at an end away from the first gas inlet, and a combustor assembly and a cell assembly arranged in sequence along the axis inside, and the combustor assembly and the cell assembly being connected in communication through a pipeline; a heat exchange assembly arranged in the second shell, having one end in communication with the third gas inlet and the second gas inlet respectively, and the other end in communication with the cell assembly.

[0005] In some embodiments, the heat exchange assembly is connected to the third gas inlet through a first gas inlet pipe and connected to the second gas inlet through a second gas inlet pipe. The other end of the heat exchange assembly is connected to the cathode of the stack assembly through a first gas outlet pipe and connected to the anode of the stack assembly through a second gas outlet pipe.

[0006] In some embodiments, the heat exchange assembly comprises: a heat exchanger shell, which is provided with two parallel partition plates to divide the heat exchanger shell into: a first cavity, which is connected to the second gas inlet pipe and the second gas outlet pipe; a second cavity, which is provided on both sides of the first cavity and connected to the first gas inlet pipe and the first gas outlet pipe, respectively; the first cavity is provided with heat exchange pipes, and both ends of the heat exchange pipes are connected to the second cavity.

[0007] In some embodiments, the heat exchange pipes are arranged in a spiral shape. In some embodiments, the heat exchange pipes are arranged in parallel.

[0008] In some embodiments, the second gas inlet pipe and the second gas outlet pipe are arranged diagonally.

[0009] In some embodiments, the second gas inlet pipe is provided with a reformer.

[0010] In some embodiments, the burner assembly is arranged with several heat flow baffles along the axial direction, the heat flow baffles are provided with notches, and the notches of adjacent heat flow baffles are arranged oppositely.

[0011] In some embodiments, the heat exchange assembly is arranged on the side wall of the burner assembly along the axial direction of the second shell.

[0012] In some embodiments, the reformer is arranged on the side wall of the burner assembly along the axial direction of the second shell.

[0013] In a second aspect, a solid oxide fuel cell is provided, which comprises the solid oxide fuel cell gas inlet preheating structure.

[0014] The embodiment of the present application provides a solid oxide fuel cell air inlet preheating structure and a cell, a first shell and a second shell are coaxial and are arranged at intervals, since the fuel temperature is relatively high in the cell system, and the air is relatively low in temperature due to insufficient interlayer heat exchange, a heat exchange assembly is arranged in the second shell, the air is further heated by using the heat exchange assembly, so that the air and the fuel temperature are controlled within a certain temperature difference range before entering the cell stack assembly. The interlayer is arranged to insulate the system, the flowing air is a good insulation layer, the temperature of the outer surface of the first shell is reduced, the use of thermal insulation materials can be reduced, the weight of the fuel cell is further reduced, and the weight and volume of the system are reduced for the portable mobile power supply system. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0016] Figure 1 A structure schematic diagram of the solid oxide fuel cell air inlet preheating structure provided by the embodiment of the present application is provided. Figure 2 A cross-sectional schematic diagram of the solid oxide fuel cell air inlet preheating structure provided by the embodiment of the present application is provided. Figure I Figure 3 A cross-sectional schematic diagram of the solid oxide fuel cell air inlet preheating structure provided by the embodiment of the present application is provided. Figure II Figure 4 An internal structure schematic diagram of the solid oxide fuel cell air inlet preheating structure provided by the embodiment of the present application is provided. Figure 5 A heat exchange assembly structure schematic diagram of the solid oxide fuel cell air inlet preheating structure provided by the embodiment of the present application is provided.

[0017] In the figure: 1, first shell; 101, first gas inlet; 102, second gas inlet; 103, tail gas outlet; 2, second shell; 201, third gas inlet; 3, combustor assembly; 4, cell stack assembly; 5, heat exchange assembly; 501, heat exchanger shell; 502, partition plate; 503, first cavity; 504, second cavity; 505, heat exchange pipe; 6, first air inlet pipeline; 7, second air inlet pipeline; 8, first air outlet pipeline; 9, second air outlet pipeline; 10, reformer; 11, hot flow partition plate; 111, notch. DETAILED DESCRIPTION​​

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] This application provides a solid oxide fuel cell inlet preheating structure, which can solve the problem that conventional SOFC systems in related technologies are large in size and heavy in weight due to the use of bulky finned heat exchangers and excessively thick insulation materials, making it difficult to meet the lightweight and miniaturization requirements of application scenarios such as portable power supplies.

[0020] like Figures 1 to 3 As shown, a solid oxide fuel cell inlet preheating structure includes: The first housing 1 has a first gas inlet 101, a second gas inlet 102 and an exhaust gas outlet 103 at one end. The exhaust gas outlet 103 extends into the interior of the second housing 2 through a pipe that passes through the first housing 1 and the second housing 2. The second housing 2 is coaxially and spaced apart inside the first housing 1. The first housing 1 and the second housing 2 form a sandwich. The second housing 2 has a third gas inlet 201 at the end away from the first gas inlet 101. Inside, a burner assembly 3 and a fuel cell assembly 4 are arranged sequentially along the axial direction. The burner assembly 3 is close to the third gas inlet 201, and the burner assembly 3 and the fuel cell assembly 4 are connected by a pipe. The heat exchange component 5 is disposed inside the second housing 2, with one end connected to the third gas inlet 201 and the second gas inlet 102 respectively, and the other end connected to the fuel cell assembly 4.

[0021] The first housing 1 and the second housing 2 are coaxially spaced and form an annular interlayer channel between them. Air or oxygen enters the interlayer from the first gas inlet 101, flows along the annular channel, forming a gaseous heat insulation layer, which reduces the outer surface temperature of the first housing 1. The air preheated by the interlayer enters the interior of the second housing 2 from the third gas inlet 201 and enters the cathode side of the fuel cell stack assembly 4. The fuel gas enters the anode side of the fuel cell stack assembly 4 from the second gas inlet 102, passing through the first housing 1 and the second housing 2. Since the fuel gas temperature in the battery system is high, while the air temperature is low due to insufficient heat exchange in the interlayer, a heat exchange assembly 5 is installed before entering the fuel cell stack assembly 4. The heat exchange assembly 5 exchanges heat between the air and the fuel gas, reducing the risk of the fuel gas overheating due to the reforming reaction. At the same time, the heat exchange assembly 5 further heats the air, ensuring that the temperature difference between the air and the fuel gas is controlled within a reasonable range before entering the fuel cell stack assembly 4, thus reducing thermal stress.

[0022] At the same time, the flowing air forms a convection heat shield in the interlayer, reducing the heat loss of the system to the outside, reducing the temperature of the outer surface of the first shell 1, reducing the dependence on external thermal insulation materials, and further reducing the weight of the fuel cell. For portable mobile power supply systems, the weight and volume of the system are reduced.

[0023] Further, as shown in Figure 2 The burner assembly 3 is a square structure, and the heat exchange assembly 5 and the reformer 10 are arranged along the axis direction of the second shell 2 on the side wall of the burner assembly 3. The burner assembly 3, the heat exchange assembly 5, the reformer 10, and the stack assembly 4 are distributed along the same axis, avoiding the redundant space occupation of the traditional annular or scattered layout, and are especially suitable for portable SOFC systems. The high-temperature burner assembly 3 is adjacent to the heat exchange assembly 5 and the reformer 10, and the heat is directly conducted through the side wall, reducing heat loss.

[0024] Further, one end of the heat exchange assembly 5 is connected to the third gas inlet 201 through the first gas inlet pipe 6 and connected to the second gas inlet 102 through the second gas inlet pipe 7; The other end of the heat exchange assembly 5 is connected to the cathode of the stack assembly 4 through the first gas outlet pipe 8 and connected to the anode of the stack assembly 4 through the second gas outlet pipe 9.

[0025] Further, the second gas inlet pipe 7 is provided with the reformer 10.

[0026] Further, as shown in Figure 1 And Figure 5 The heat exchange assembly 5 comprises: The heat exchanger shell 501 is fixed on the side wall of the burner assembly 3, and the opposite surface away from the burner assembly 3 is arc-shaped and fits the inner wall of the second shell 2. Two parallel partition plates 502 are arranged in the heat exchanger shell 501, which divides the heat exchanger shell 501 into: The first cavity 503 is connected to the second gas inlet pipe 7 and the second gas outlet pipe 9; The second cavity 504 is arranged on both sides of the first cavity 503 and is connected to the first gas inlet pipe 6 and the first gas outlet pipe 8, respectively.

[0027] It should be noted that the volume of the first cavity 503 is greater than the volume of the second cavity 504.

[0028] The heat exchange pipe 505 is arranged in the first cavity 503, and the two ends of the heat exchange pipe 505 are connected to the second cavity 504.

[0029] After the gas passes through the reformer 10, the temperature is high, the second gas inlet pipe 7 penetrates through the side wall of the heat exchanger shell 501 and one of the partition plates 502 to enter the first cavity 503, the first cavity 503 is filled with high-temperature gas, air / oxygen enters the second cavity 504 from the first gas inlet pipe 6, the air / oxygen in the second cavity 504 is heated by the heat exchange pipe 505 and then enters the second cavity 504 on the other side, and then flows into the cathode side of the stack assembly 4 from the first gas outlet pipe 8, and the high-temperature gas in the first cavity 503 is cooled and then enters the anode side of the stack assembly 4 from the second gas outlet pipe 9.

[0030] In the embodiment, the heat exchange pipe 505 is provided with a plurality of heat exchange pipes 505 arranged in parallel to increase the heat exchange area and strengthen the heat transfer effect.

[0031] In some optional embodiments, the heat exchange pipe 505 is arranged in a spiral to prolong the air / oxygen flow path and improve the heat exchange time.

[0032] Further, the second gas inlet pipe 7 and the second gas outlet pipe 9 are arranged diagonally. The diagonal arrangement prolongs the residence time of the gas in the first cavity 503 and ensures sufficient heat exchange.

[0033] Further, as shown in Figure 3 and Figure 4 , the burner assembly 3 is arranged with a plurality of heat flow baffles 11 along the axial direction, the heat flow baffles 11 are provided with notches 111, and the notches 111 of adjacent heat flow baffles 11 are arranged oppositely. The gas flow presents a serpentine flow, the heat exchange area is increased, and the convective heat transfer coefficient of the gas-solid surface is increased.

[0034] The application also provides a solid oxide fuel cell, comprising a solid oxide fuel cell gas inlet preheating structure.

[0035] The working process of the application is as follows: When working, the burner assembly 3 works to generate high-temperature flue gas to heat the reformer 10 and the heat exchange assembly 5, fuel (supplied by an external outdoor portable gas tank) enters the reformer 10 from the second gas inlet 102 through the first shell 1 and the second shell 2, and the hydrogen and carbon monoxide generated after reforming are at a high temperature, and enter the first cavity 503 of the heat exchange assembly 5 from the second gas inlet pipe 7, so that the first cavity 503 is filled with high-temperature fuel gas. At the same time, air (supplied by a fan) enters the interlayer from the first gas inlet 101 and flows along the annular channel to form a gaseous heat insulation layer to reduce the temperature of the outer surface of the first shell 1. The air preheated by the interlayer enters the second shell 2 from the third gas inlet 201, enters the second cavity 504 from the first gas inlet pipe 6, and enters the other side of the second cavity 504 after heat exchange through the heat exchange pipe 505. The high-temperature fuel gas in the first cavity 503 enters the cathode side of the stack assembly 4 from the second gas outlet pipe 9 after being cooled, so as to avoid that the sealing material, the metal support, the cathode material and the anode material in the stack assembly 4 are deactivated due to a large temperature difference. After the gas reacts in the cathode and the anode, the remaining gas enters the burner assembly 3 from the stack assembly 4 for combustion, and then flows out from the tail gas outlet 103 after being folded back.

[0036] In the structure, the temperature of the fuel in the system is too high due to the reforming reaction, and the temperature of the air is too low due to insufficient heat exchange in the interlayer. To solve this problem, a simple heat exchange assembly 5 is added inside the hot area to reduce the over-temperature of the reforming reaction, and the air is further heated by using the heat to ensure that the temperature of the air and the fuel before entering the stack is controlled within a certain temperature difference range.

[0037] In the description of the present application, it should be noted that the terms "upper", "lower" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] It should be noted that, in the present application, the relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0039] The foregoing is merely illustrative of the principles of the application and various modifications can be made by those skilled in the art without departing from the spirit and scope of the application. The above embodiments are illustrative, and not restrictive, of the scope of the application.

Claims

1. A preheating structure for the intake air of a solid oxide fuel cell, characterized in that, include: The first housing (1) is provided with a first gas inlet (101), a second gas inlet (102) and an exhaust gas outlet (103). The second housing (2) is coaxially and spaced apart inside the first housing (1). A third gas inlet (201) is provided at the end away from the first gas inlet (101). Inside, a burner assembly (3) and a fuel cell assembly (4) are arranged sequentially along the axial direction. The burner assembly (3) and the fuel cell assembly (4) are connected by a pipe. The exhaust gas outlet (103) passes through the first housing (1) and the second housing (2) through a pipe. The heat exchange assembly (5) is disposed in the second housing (2), with one end connected to the third gas inlet (201) and the second gas inlet (102) respectively, and the other end connected to the fuel cell assembly (4).

2. The solid oxide fuel cell inlet preheating structure as described in claim 1, characterized in that: One end of the heat exchange component (5) is connected to the third gas inlet (201) through the first air inlet pipe (6), and the other end is connected to the second gas inlet (102) through the second air inlet pipe (7). The other end of the heat exchange component (5) is connected to the cathode of the fuel cell assembly (4) through the first exhaust pipe (8), and to the anode of the fuel cell assembly (4) through the second exhaust pipe (9).

3. The solid oxide fuel cell inlet preheating structure as described in claim 2, characterized in that: The heat exchange assembly (5) includes: The heat exchanger shell (501) has two parallel partition plates (502) inside, which divide the heat exchanger shell (501) into the following shapes: - The first cavity (503) is connected to the second air inlet pipe (7) and the second air outlet pipe (9); - The second cavity (504) is disposed on both sides of the first cavity (503) and is connected to the first air inlet pipe (6) and the first air outlet pipe (8) respectively; The first cavity (503) is provided with a heat exchange tube (505), and the two ends of the heat exchange tube (505) are respectively connected to the second cavity (504).

4. The solid oxide fuel cell inlet preheating structure as described in claim 3, characterized in that: The heat exchange tube (505) is arranged in a spiral; And / or, the heat exchange tube (505) is provided with multiple tubes, and the multiple heat exchange tubes (505) are arranged in parallel.

5. The solid oxide fuel cell inlet preheating structure as described in claim 2, characterized in that: The second air intake pipe (7) and the second air outlet pipe (9) are arranged diagonally.

6. The solid oxide fuel cell inlet preheating structure as described in claim 2, characterized in that: A reformer (10) is provided on the second air intake pipe (7).

7. The solid oxide fuel cell inlet preheating structure as described in claim 1, characterized in that: The burner assembly (3) has several heat flow baffles (11) spaced apart along the axial direction. The heat flow baffles (11) have notches (111) and the notches (111) of adjacent heat flow baffles (11) are arranged opposite to each other.

8. The solid oxide fuel cell inlet preheating structure as described in claim 1, characterized in that: The heat exchange component (5) is disposed on the side wall of the burner assembly (3) along the axial direction of the second housing (2).

9. The solid oxide fuel cell inlet preheating structure as described in claim 1, characterized in that: The reformer (10) is disposed on the side wall of the burner assembly (3) along the axial direction of the second housing (2).

10. A solid oxide fuel cell, characterized in that: Includes the solid oxide fuel cell inlet preheating structure as described in any one of claims 1 to 9.

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