Centralized gas supply fuel cell system

Abstract

The embodiment of the invention provides a fuel cell system for centralized gas supply. The fuel cell system comprises a fuel cell stack, an air inlet pipe, a communicating air pipe, a cooling liquid circulating pipe and a heat exchange component. The heat exchange component is provided with a heat pipe cavity and a cold pipe cavity, the fuel cell stack is communicated with the heat pipe cavity of the heat exchanger through the cooling liquid circulating pipe, and the air inlet pipe is sequentially communicated with the cold pipe cavity of the heat exchanger, the communicating air pipe and the fuel cell stack; therefore, heat exchange between the cooling liquid and the air in the heat exchange component is achieved. The cooling liquid led out of the fuel cell stack is led out to heat the air before entering the stack, so that the problem that the performance of a membrane electrode is reduced due to the fact that the voltage of a single fuel cell is too low is avoided. Therefore, the fuel cell system for centralized gas supply according to the embodiment of the invention has the advantage of improving the output performance of the fuel cell.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a fuel cell system with centralized gas supply. Background Art

[0002] At present, the power of a single fuel cell system is generally low. For high-power application scenarios, an independent air supply method with multiple fuel cells connected in parallel is generally adopted. The fuel cell air subsystem of this type of air supply generally includes key components such as air filters, air compressors, intercoolers and humidifiers. The heat source of the air temperature entering the stack is mainly provided by the air compressor. Therefore, multiple sets of air compressors and auxiliary accessories will be selected, resulting in a large number of parts, large volume, and complex control, and there is a problem of high equipment investment cost. Not only that, the power generation capacity is usually only 200-300kw, which is difficult to meet the needs of high-power power generation scenarios. Summary of the invention

[0003] The present invention is based on the inventor's discovery and understanding of the following facts and problems: centralized air supply is a method of using an air compressor to supply air to multiple fuel cell stacks at the same time. This method of air supply can greatly increase the power generation capacity, and the power generation capacity can reach megawatts and above. During the research process, it was found that after the centralized air supply is compressed by the air compressor and enters the fuel cell stack through the pipeline, the temperature is usually around 20-40°C. The low air inlet temperature can easily cause the fuel cell single chip voltage to be too low, which will also cause the performance of the membrane electrode to decline.

[0004] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, an embodiment of the present invention provides a fuel cell system with centralized gas supply. The fuel cell system has the advantages of reducing equipment investment costs and improving the output performance of fuel cells.

[0005] The centralized gas supply fuel cell system of the embodiment of the present invention includes a fuel cell stack, an air intake pipe, a connecting air pipe, a coolant circulation pipe and a heat exchange component.

[0006] The heat exchange component has a hot tube cavity and a cold tube cavity, the fuel cell stack is connected to the hot tube cavity of the heat exchanger through the coolant circulation pipe, the air intake pipe is connected to the cold tube cavity of the heat exchanger, and the cold tube cavity is connected to the fuel cell stack through the connecting air pipe. It can be understood that the air entering the fuel cell stack is heated by the coolant inside the stack to increase the temperature of the air entering the stack.

[0007] The centralized gas supply fuel cell system of the embodiment of the present invention heats the air entering the fuel cell stack by draining the coolant inside the fuel cell stack and exchanging heat with the air before entering the stack, thereby avoiding the problem of too low temperature of the air entering the stack causing the single fuel cell voltage to be too low, resulting in a decrease in membrane electrode performance. At the same time, the coolant inside the stack exchanges heat with the air entering the stack, and the coolant after heat exchange with the air also relieves the pressure of cooling the coolant circulation to a certain extent. In addition, appropriately increasing the intake temperature can also better control the humidity level in the battery and avoid the problem of battery performance degradation caused by over-humidity or over-dryness. For example, at lower temperatures, water may more easily condense into liquid to block the gas channel; at higher temperatures, it is more conducive to maintaining an appropriate humidity state to ensure good ion conductivity.

[0008] At the same time, for independent air supply, the temperature of the air compressed by the air compressor is generally too high (over 100°C), and usually an additional intercooler is required for cooling. The use of centralized air supply can not only save equipment investment costs, but also avoid the installation of cooling equipment. This reduces equipment investment costs and effectively avoids the consumption of additional electrical power. Therefore, the centralized air supply fuel cell system has the advantages of reducing costs and increasing efficiency.

[0009] In addition, for the problem of low temperature entering the stack caused by centralized air supply, the air can be heated without installing a new heating device, which not only reduces the equipment investment cost, but also synergistically cools the coolant in the fuel cell stack, reducing the power consumed by lowering the coolant temperature. Therefore, the centralized air supply fuel cell system of the embodiment of the present invention has the advantages of reducing costs and increasing efficiency.

[0010] Therefore, the centralized gas supply fuel cell system of the embodiment of the present invention has the advantages of reducing equipment investment costs and improving performance.

[0011] In some embodiments, the coolant circulation pipe includes an inlet pipe and a return pipe, wherein both ends of the inlet pipe are respectively connected to the coolant outlet of the fuel cell stack and the coolant inlet of the heat pipe cavity of the heat exchange component, and both ends of the return pipe are respectively connected to the coolant inlet of the fuel cell stack and the coolant outlet of the heat pipe cavity of the heat exchange component.

[0012] In some embodiments, the centralized gas supply fuel cell system also includes a coolant flow controller and a first temperature sensor, the coolant flow controller and the first temperature sensor signals respond to each other, the coolant flow controller is arranged on the liquid inlet pipe, and the first temperature sensor is arranged in the coolant chamber in the fuel cell stack to obtain the current temperature of the coolant in the coolant chamber.

[0013] In some embodiments, the centralized air supply fuel cell system also includes an air flow controller and at least one of the proportional valves and a first temperature sensor, the air flow controller and / or the proportional valve are arranged on the intake pipe, and the first temperature sensor is arranged on the intake pipe to obtain the temperature of the air before heat exchange.

[0014] In some embodiments, the centralized air supply fuel cell system further includes an air filter, which is disposed on the air intake pipe and is disposed at the front end of the air flow controller.

[0015] In some embodiments, the centralized gas supply fuel cell system further includes a gas storage tank, and the gas storage tank is connected to the inlet of the air intake pipe.

[0016] In some embodiments, the heat exchange component is a heat exchanger or an intercooler.

[0017] In some embodiments, the heat exchanger is at least one of a plate heat exchanger, a spiral plate heat exchanger, a shell and tube heat exchanger, and a shell and tube heat exchanger.

[0018] In some embodiments, the centralized gas supply fuel cell system further includes a humidifier, and the humidifier is disposed on the connecting air pipe to increase the air humidity in the connecting air pipe.

[0019] In some embodiments, a cathode outlet of the fuel cell stack is in communication with a wet side inlet of the humidifier.

[0020] In some embodiments, the centralized gas supply fuel cell system further includes a back pressure valve, which is disposed downstream of the wet side outlet of the humidifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the process flow of the centralized gas supply fuel cell system of the present invention.

[0022] Figure 2 It is a schematic diagram of a heat exchange device of the present invention.

[0023] Reference numerals:

[0024] Fuel cell stack 1;

[0025] Intake pipe 2; connecting air pipe 3;

[0026] Liquid inlet pipe 41; Liquid return pipe 42;

[0027] Heat exchange component 5; hot tube cavity 51; cold tube cavity 52;

[0028] Coolant flow controller 6;

[0029] Air filter 7;

[0030] Air flow controller 8;

[0031] Humidifier 9;

[0032] Back pressure valve 10. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0034] Reference below Figure 1-Figure 2 A fuel cell system with centralized gas supply according to an embodiment of the present invention is described.

[0035] The centralized gas supply fuel cell system of the embodiment of the present invention includes a fuel cell stack 1 , an air intake pipe 2 , a connecting air pipe 3 , a coolant circulation pipe and a heat exchange component 5 .

[0036] The heat exchange component 5 has a hot tube cavity 51 and a cold tube cavity 52. ​​The fuel cell stack 1 is connected to the hot tube cavity 51 of the heat exchanger through a coolant circulation pipe, the air intake pipe 2 is connected to the cold tube cavity 52 of the heat exchanger, and the cold tube cavity 52 is connected to the fuel cell stack 1 through a connecting air pipe 3. It can be understood that the air entering the fuel cell stack 1 is heated by the coolant inside the stack to increase the temperature of the air entering the stack.

[0037] The centralized gas supply fuel cell system of the embodiment of the present invention heats the air entering the fuel cell stack by draining the coolant inside the fuel cell stack and exchanging heat with the air before entering the stack, thereby avoiding the problem of too low temperature of the air entering the stack causing the single fuel cell voltage to be too low, resulting in a decrease in membrane electrode performance. At the same time, the coolant inside the stack exchanges heat with the air entering the stack, and the coolant after heat exchange with the air also relieves the pressure of cooling the coolant circulation to a certain extent. In addition, appropriately increasing the intake temperature can also better control the humidity level in the battery and avoid the problem of battery performance degradation caused by over-humidity or over-dryness. For example, at lower temperatures, water may more easily condense into liquid to block the gas channel; at higher temperatures, it is more conducive to maintaining an appropriate humidity state to ensure good ion conductivity.

[0038] At the same time, for independent air supply, the temperature of the air compressed by the air compressor is generally too high (over 100°C), and usually an additional intercooler is required for cooling. The use of centralized air supply can not only save equipment investment costs, but also avoid the installation of cooling equipment. This reduces equipment investment costs and effectively avoids the consumption of additional electrical power. Therefore, the centralized air supply fuel cell system has the advantages of reducing costs and increasing efficiency.

[0039] In addition, for the problem of low temperature entering the stack caused by centralized air supply, the air can be heated without installing a new heating device, which not only reduces the equipment investment cost, but also synergistically cools the coolant in the fuel cell stack, reducing the power consumed by lowering the coolant temperature. Therefore, the centralized air supply fuel cell system of the embodiment of the present invention has the advantages of reducing costs and increasing efficiency.

[0040] Therefore, the centralized gas supply fuel cell system of the embodiment of the present invention has the advantages of reducing equipment investment costs and improving performance.

[0041] like Figure 1 and Figure 2 As shown, the coolant circulation pipe includes an inlet pipe 41 and a return pipe 42. The two ends of the inlet pipe 41 are respectively connected to the coolant outlet of the fuel cell stack 1 and the coolant inlet of the heat pipe cavity 51 of the heat exchange component 5. The two ends of the return pipe 42 are respectively connected to the coolant inlet of the fuel cell stack 1 and the coolant outlet of the heat pipe cavity 51 of the heat exchange component 5.

[0042] The centralized gas supply fuel cell system of the embodiment of the present invention divides the coolant circulation pipe into a liquid inlet pipe 41 and a liquid return pipe 42, and then the two ends of the liquid inlet pipe 41 are respectively connected to the coolant outlet of the fuel cell stack 1 and the coolant inlet of the heat pipe cavity 51 of the heat exchange component 5, and the two ends of the liquid return pipe 42 are respectively connected to the coolant inlet of the fuel cell stack 1 and the coolant outlet of the heat pipe cavity 51 of the heat exchange component 5, so as to lead out the coolant inside the fuel cell stack 1 and exchange heat with the heat exchange component 5. Therefore, the centralized gas supply fuel cell system of the embodiment of the present invention has the advantages of simple structure and strong adaptability.

[0043] Furthermore, the liquid inlet pipe 41 and the liquid return pipe 42 are both connected to the cooling liquid chamber in the fuel cell stack 1 , and the liquid inlet pipe 41 and the liquid return pipe 42 can be connected to the cooling liquid chamber through a connector.

[0044] like Figure 1 As shown, the centralized gas supply fuel cell system of an embodiment of the present invention also includes a signal-responsive coolant flow controller 6 and a first temperature sensor. The coolant flow controller 6 is arranged on the liquid inlet pipe 41, and the first temperature sensor is arranged in the coolant chamber in the fuel cell stack 1 to obtain the current temperature of the coolant in the coolant chamber.

[0045] The centralized gas supply fuel cell system of the embodiment of the present invention can control the flow rate of the coolant through the cooperation between the coolant flow controller 6 and the first temperature sensor, thereby facilitating the stable gas exchange and mass transfer with the intake air, so as to ensure the stability of the intake air temperature, thereby improving the overall performance of the fuel cell.

[0046] like Figure 1 As shown, the centralized air supply fuel cell system of the embodiment of the present invention further includes an air flow controller 8 and / or a proportional valve and a second temperature sensor, the air flow controller 8 and / or the proportional valve are arranged on the intake pipe 2, and the second temperature sensor is arranged on the intake pipe 2 to obtain the temperature of the air before heat exchange. This helps to control the stability of the intake temperature and intake volume to maintain the normal operation of the fuel cell.

[0047] Furthermore, the proportional valve is a proportional valve that controls the opening.

[0048] like Figure 1 As shown, the centralized air supply fuel cell system of the embodiment of the present invention further includes an air filter 7 , which is disposed on the air intake pipe 2 , and the air filter 7 is disposed at the front end of the air flow controller 8 .

[0049] The centralized air supply fuel cell system of the embodiment of the present invention can purify the air before entering the fuel cell stack 1 through the air filter 7, thereby preventing dust in the air from entering the fuel cell stack 1 and affecting the fuel cell performance and mass transfer performance. Therefore, the centralized air supply fuel cell system improves the performance of the centralized air supply fuel cell system.

[0050] like Figure 1 As shown, the centralized gas supply fuel cell system of the embodiment of the present invention further includes a gas storage tank, which is connected to the inlet of the air intake pipe 2. According to the operating conditions of the fuel cell stack, the pipeline air flow is regulated to meet the flow control of different operating conditions.

[0051] The heat exchange component 5 is a heat exchanger or an intercooler.

[0052] Optionally, the heat exchanger is a plate heat exchanger, a spiral plate heat exchanger, a shell and tube heat exchanger or a shell and tube heat exchanger, which serves the purpose of heating the incoming air without adding any additional auxiliary parts, thus reducing the cost of equipment investment.

[0053] In addition, when the heat exchange element 5 is an intercooler, the inlet and outlet of the intercooler coolant for the fuel cell are reversed, that is, the stack coolant outlet is connected to the intercooler coolant inlet, and the intercooler coolant outlet is connected to the stack coolant inlet, both of which can achieve the purpose of fuel cell air heating under centralized air supply mode.

[0054] like Figure 1 As shown, the centralized air supply fuel cell system of the embodiment of the present invention further includes a humidifier 9 , which is disposed on the air communication pipe 3 to increase the air humidity in the air communication pipe 3 .

[0055] The air heated by the heat exchanger enters the dry side inlet of the humidifier 9 for humidification. The outlet of the humidifier 9 is connected to the air inlet of the fuel cell stack 1, and the humidified heated air is input into the fuel cell stack 1. The high temperature and high humidity gas at the outlet of the fuel cell stack 1 is connected to the wet inlet of the humidifier 9, which is the source of humidity for the humidifier 9.

[0056] The cathode outlet of the fuel cell stack 1 is connected to the wet side inlet of the humidifier 9. Since the exhaust gas temperature is relatively high, the exhaust gas can be reused to heat the intake air, further improving the utilization of the stack energy.

[0057] The centralized gas supply fuel cell system of the embodiment of the present invention further includes a back pressure valve 10, which is arranged downstream of the wet side outlet of the humidifier 9. Thus, while the exhaust gas is discharged, the air inlet pressure is adjusted by adjusting the opening of the back pressure valve 10, thereby achieving the purpose of adjusting the air inlet pressure.

[0058] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0059] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0060] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0063] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A fuel cell system with centralized gas supply, characterized in that: include: A fuel cell stack, an air intake pipe, a connecting air pipe, a coolant circulation pipe and a heat exchange component, wherein the heat exchange component has a hot tube cavity and a cold tube cavity, the fuel cell stack is connected to the hot tube cavity of the heat exchanger through the coolant circulation pipe, the air intake pipe is connected to the cold tube cavity of the heat exchanger, the connecting air pipe and the fuel cell stack are connected in sequence, so as to realize heat exchange between coolant and air in the heat exchange component.

2. The centralized gas supply fuel cell system according to claim 1, characterized in that: The coolant circulation pipe includes an inlet pipe and a return pipe, the two ends of the inlet pipe are respectively connected to the coolant outlet of the fuel cell stack and the coolant inlet of the heat pipe cavity of the heat exchange component, and the two ends of the return pipe are respectively connected to the coolant inlet of the fuel cell stack and the coolant outlet of the heat pipe cavity of the heat exchange component.

3. The centralized gas supply fuel cell system according to claim 2, characterized in that: It also includes a coolant flow controller and a first temperature sensor, the coolant flow controller and the first temperature sensor signals respond to each other, the coolant flow controller is arranged on the liquid inlet pipe, and the first temperature sensor is arranged in the coolant chamber in the fuel cell stack to obtain the current temperature of the coolant in the coolant chamber.

4. The centralized gas supply fuel cell system according to claim 1, characterized in that: It also includes at least one of an air flow controller and a proportional valve and a second temperature sensor, the air flow controller and / or the proportional valve are arranged on the intake pipe, and the second temperature sensor is arranged on the intake pipe to obtain the temperature of the air before intake.

5. The centralized gas supply fuel cell system according to claim 4, characterized in that: It also includes an air filter, which is arranged on the air intake pipe and at the front end of the air flow controller.

6. The centralized gas supply fuel cell system according to claim 1, characterized in that: It also includes an air storage tank, which is connected to the inlet of the intake pipe; and / or the heat exchange component is a heat exchanger or an intercooler.

7. The centralized gas supply fuel cell system according to claim 6, characterized in that: The heat exchanger is at least one of a plate heat exchanger, a spiral plate heat exchanger, a shell and tube heat exchanger, and a shell and tube heat exchanger.

8. The centralized gas supply fuel cell system according to claim 1, characterized in that: A humidifier is also included, and the humidifier is arranged on the communicating air pipe to increase the air humidity in the communicating air pipe.

9. The centralized gas supply fuel cell system according to claim 8, characterized in that: The cathode outlet of the fuel cell stack is in communication with the wet side inlet of the humidifier.

10. The centralized gas supply fuel cell system according to claim 9, characterized in that: A back-pressure valve is also included, and the back-pressure valve is arranged downstream of the wet-side outlet of the humidifier.

Images