A fuel cell system using compressed air

Abstract

The present application relates to a fuel cell system using compressed air, including an air filter, an air compressor, an intercooler, a switch valve, an intake combination valve, a hydrogen pump, a hydrogen bottle, a fuel cell stack and a humidifier; the air filter, the air compressor, the intercooler, the intake combination valve, the humidifier and the fuel cell stack are connected in sequence; the inlet of the switch valve is respectively connected to the air compressor and the intercooler, and the outlet of the switch valve is respectively connected to the intake combination valve, the fuel cell stack and the hydrogen pump; the hydrogen bottle is respectively connected to the fuel cell stack and the hydrogen pump. The present application heats the hydrogen pump and the fuel cell stack through the high-temperature air at the rear end of the air compressor, which facilitates the low-temperature cold start of the fuel cell system; at the same time, the gas energy in the intake combination valve bypass passage is used to dissipate heat for the hydrogen pump and the fuel cell stack, which effectively improves the overall efficiency of the fuel cell system.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a fuel cell system utilizing compressed air. Background Art

[0002] A fuel cell is a power generation device that converts the chemical energy in the fuel directly into electrical energy through an electrochemical reaction. The cold start of an existing fuel cell system generally requires PTC auxiliary heating, using electricity to continuously heat the coolant, while the water pump continues to rotate, and the coolant flows to heat the stack. In addition, the cold start of an existing fuel cell system generally adopts a low-potential cold start. At startup, a low stoichiometric ratio is used, and the concentration difference overpotential of the fuel cell is used to lower the external output efficiency of the fuel cell, converting as much chemical energy as possible into heat and using it for heating the fuel cell stack. In order to adjust the characteristics of the air compressor, when the fuel cell is operating normally, the air in the bypass passage of the intake combination valve is discharged.

[0003] However, the use of PTC auxiliary heating requires the addition of additional electronic control components, which increases the complexity and cost of the fuel cell system and also increases energy consumption. In addition, low-potential cold start has relatively high requirements for the fuel cell stack, requiring precise control of the anode and cathode stoichiometric ratio, which is difficult to operate and has poor universality. Moreover, after the fuel cell is running, the gas in the bypass passage of the intake combination valve is directly discharged through the tail pipe, wasting this part of the gas energy. Summary of the invention

[0004] Based on this, the present invention provides a fuel cell system utilizing compressed air, aiming to solve technical problems such as the need to add additional electronic control components for cold start of existing fuel cell systems, complexity of fuel cell systems, high costs, high energy consumption, high requirements for fuel cell stacks, high operating difficulty and poor universality.

[0005] To achieve the above-mentioned purpose, the embodiment of the present invention proposes the following technical solution: a fuel cell system using compressed air, comprising an air filter, an air compressor, an intercooler, a switch valve, an intake combination valve, a hydrogen pump, a hydrogen bottle, a fuel cell stack and a humidifier; the air filter, the air compressor, the intercooler, the intake combination valve, the humidifier and the fuel cell stack are connected in sequence;

[0006] The inlet of the switch valve is connected to the air compressor and the intercooler respectively, and the outlet of the switch valve is connected to the intake combination valve, the fuel cell stack and the hydrogen pump respectively; the hydrogen bottle is connected to the fuel cell stack and the hydrogen pump respectively.

[0007] As a preferred embodiment, the air outlet of the air compressor is connected to the intercooler and the switch valve respectively; the air outlet of the air intake combination valve is connected to the air inlet of the humidifier and the air outlet of the switch valve respectively.

[0008] As a preferred embodiment, the fuel cell system further includes a water separator and a drain valve, wherein the water separator is respectively connected to the drain valve, the fuel cell stack and the hydrogen pump; and the drain valve is respectively connected to the hydrogen pump and the first tail drain.

[0009] As a preferred embodiment, the water outlet of the fuel cell stack is connected to the water separator and the hydrogen pump respectively.

[0010] As a preferred embodiment, the fuel cell system further comprises a pressure reducing valve, and the pressure reducing valve is respectively connected to the fuel cell stack, the hydrogen bottle, and the hydrogen pump.

[0011] As a preferred embodiment, the hydrogen inlet of the fuel cell stack is connected to the pressure reducing valve; the gas outlet of the hydrogen pump is connected to the pressure reducing valve and the hydrogen bottle respectively.

[0012] As a preferred embodiment, the fuel cell system further comprises a back pressure valve and a second tail drain, and the back pressure valve is connected to the humidifier, the fuel cell stack, and the second tail drain respectively.

[0013] As a preferred embodiment, the fuel cell stack is arranged in a fuel cell stack packaging box; the fuel cell stack packaging box is adapted to the fuel cell stack; and the fuel cell stack packaging box is connected to the switch valve.

[0014] As a preferred implementation, the hydrogen pump is disposed in a hydrogen pump packaging box; the hydrogen pump packaging box is adapted to the hydrogen pump; and the hydrogen pump packaging box is connected to the switch valve.

[0015] As a preferred embodiment, the fuel cell stack is a proton exchange membrane fuel cell stack (PEMFC).

[0016] This application uses the high-temperature air at the rear end of the air compressor to heat the hydrogen pump and the fuel cell stack, which facilitates the low-temperature cold start of the fuel cell system; at the same time, the gas energy in the bypass passage of the intake combination valve is used to dissipate heat for the hydrogen pump and the fuel cell stack, effectively improving the overall efficiency of the fuel cell system. The system of this application can effectively solve the cold start problem of the fuel cell system, and has the following advantages:

[0017] (1) The PTC heater is removed, reducing system costs; and low-potential cold start is not required, which increases the technical universality of low-temperature cold start of fuel cells. The high-temperature air generated by the air compressor is used to heat the hydrogen pump and the fuel cell stack at the same time, effectively utilizing the energy generated by existing components, making it easier to successfully cold start the fuel cell and reducing the risk of damage to the stack due to cold start failure of the fuel cell system;

[0018] (2) When the fuel cell system is operating normally, the gas flow bypassing the intake combination valve at the rear end of the air compressor can be used to dissipate heat for the fuel cell stack and hydrogen pump, effectively reducing the power consumption of the fan and water pump during operation, saving energy, and effectively improving the overall efficiency of the fuel cell system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0020] Figure 1 This is a schematic structural diagram of a fuel cell system using compressed air according to an embodiment of the present invention;

[0021] Figure 2 To adopt Figure 1 Schematic diagram of the working process of a fuel cell system using compressed air.

[0022] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In this application, 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 connection; it can be a mechanical connection or an electrical connection; 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 this application can be understood according to specific circumstances.

[0026] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0027] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their 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 addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] Specifically, Figure 1 As shown, an embodiment of the present invention provides a fuel cell system using compressed air, including an air filter 10, an air compressor 20, an intercooler 30, a switch valve 40, an intake combination valve 50, a hydrogen pump 60, a hydrogen bottle 70, a fuel cell stack 80 and a humidifier 90; the air filter 10, the air compressor 20, the intercooler 30, the intake combination valve 50, the humidifier 90 and the fuel cell stack 80 are connected in sequence;

[0029] The inlet of the switch valve 40 is connected to the air compressor 20 and the intercooler 30 respectively, and the outlet of the switch valve 40 is connected to the intake combination valve 50, the fuel cell stack 80, and the hydrogen pump 60 respectively; the hydrogen bottle 70 is connected to the fuel cell stack 80 and the hydrogen pump 60 respectively.

[0030] As a preferred embodiment, the air outlet of the air compressor 20 is connected to the intercooler 30 and the switch valve 40 respectively; the air outlet of the intake combination valve 50 is connected to the air inlet of the humidifier 90 and the air outlet of the switch valve 40 respectively.

[0031] As a preferred embodiment, the fuel cell system further includes a water separator 100 and a drain valve 110, wherein the water separator 100 is respectively connected to the drain valve 110, the fuel cell stack 80, and the hydrogen pump 60; the drain valve 110 is respectively connected to the hydrogen pump 60 and the first tail row A.

[0032] As a preferred embodiment, the water outlet of the fuel cell stack 80 is connected to the water separator 100 and the hydrogen pump 60 respectively.

[0033] As a preferred embodiment, the fuel cell system further includes a pressure reducing valve 120 , and the pressure reducing valve 120 is connected to the fuel cell stack 80 , the hydrogen bottle 70 , and the hydrogen pump 60 , respectively.

[0034] As a preferred embodiment, the hydrogen inlet of the fuel cell stack 80 is connected to the pressure reducing valve 120; the gas outlet of the hydrogen pump 60 is connected to the pressure reducing valve 120 and the hydrogen bottle 70 respectively.

[0035] As a preferred embodiment, the fuel cell system further includes a back pressure valve 130 and a second tail row B. The back pressure valve 130 is connected to the humidifier 90, the fuel cell stack 80, and the second tail row B respectively.

[0036] As a preferred embodiment, the fuel cell stack 80 is disposed in a fuel cell stack packaging box C; the fuel cell stack packaging box C is adapted to the fuel cell stack 80; and the fuel cell stack packaging box C is connected to the switch valve 40 (ie, connected in a communication manner).

[0037] As a preferred embodiment, the hydrogen pump 60 is disposed in a hydrogen pump packaging box D; the hydrogen pump packaging box D is adapted to the hydrogen pump 60; and the hydrogen pump packaging box D is connected to (ie, communicated with) the switch valve 40.

[0038] As a preferred embodiment, the fuel cell stack is a proton exchange membrane fuel cell stack.

[0039] like Figure 2 As shown, the fuel cell system of the present application works through a low-temperature cold start heating mode and a fuel cell operation heat dissipation mode:

[0040] When the fuel cell system works in the low-temperature cold start heating mode, the air compressor is started first, and the air is filtered through the air filter and then compressed by the air compressor to form high-temperature, high-pressure gas. At this time, the intake combination valve is closed, so the gas is not cooled by the intercooler and the gas temperature is very high; the switch valve is opened, and the high-temperature gas can only flow into the hydrogen pump packaging box and the fuel cell stack packaging box through the switch valve; as the air compressor continues to run, the temperature of the hydrogen pump and the temperature of the fuel cell stack continue to rise. When the temperature of the hydrogen pump reaches the set temperature T1 and the temperature of the fuel cell stack reaches the set temperature T2, the fuel cell system can be cold started normally.

[0041] When the fuel cell system is cold-started successfully, the fuel cell stack can output power normally, and the fuel cell system works through the fuel cell operation heat dissipation mode: at this time, the switch valve is closed, and the rear end gas of the air compressor all flows through the intercooler, the air temperature will be reduced, and the intake combination valve operates normally. The gas with reduced temperature can enter the humidifier through the intake combination valve, and can also enter the hydrogen pump packaging box and the fuel cell stack packaging box after the intake combination valve. This part of the gas is used to continuously cool the hydrogen pump and the fuel cell stack. Especially in a high-power working environment, the hydrogen pump speed is high, the hydrogen pump temperature rises quickly, and it is easy to trigger an over-temperature fault. Therefore, the hydrogen pump needs to be cooled, and the fuel cell stack will also increase heat generation and need to be cooled; using the above part of the gas to cool down can reduce the power consumption of the fan and water pump in the thermal management of the fuel cell, reduce the energy consumption of the fuel cell, and improve the efficiency of the overall system.

[0042] This application uses the high-temperature air at the rear end of the air compressor to heat the hydrogen pump and the fuel cell stack, which facilitates the low-temperature cold start of the fuel cell system; at the same time, the gas energy in the bypass passage of the intake combination valve is used to dissipate heat for the hydrogen pump and the fuel cell stack, effectively improving the overall efficiency of the fuel cell system. The system of this application can effectively solve the cold start problem of the fuel cell system, and has the following advantages:

[0043] The PTC heater has been removed, reducing system costs; and there is no need for low-potential cold start, which increases the technical universality of low-temperature cold start of the fuel cell. The high-temperature air generated by the air compressor is used to heat the hydrogen pump and the fuel cell stack at the same time, effectively utilizing the energy generated by existing components, making the fuel cell cold start easier to succeed and reducing the risk of damage to the stack due to cold start failure of the fuel cell system.

[0044] When the fuel cell system is operating normally, the gas flow bypassing the intake combination valve at the rear end of the air compressor can be used to dissipate heat for the fuel cell stack and hydrogen pump, effectively reducing the power consumption of the fan and water pump during operation, saving energy, and effectively improving the overall efficiency of the fuel cell system.

[0045] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means 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 representation of the above terms does not necessarily refer to the same embodiment or example.

[0046] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0047] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A fuel cell system using compressed air, characterized in that: It includes an air filter, an air compressor, an intercooler, a switch valve, an intake combination valve, a hydrogen pump, a hydrogen bottle, a fuel cell stack and a humidifier; the air filter, the air compressor, the intercooler, the intake combination valve, the humidifier and the fuel cell stack are connected in sequence; The inlet of the switch valve is connected to the air compressor and the intercooler respectively, and the outlet of the switch valve is connected to the intake combination valve, the fuel cell stack and the hydrogen pump respectively; the hydrogen bottle is connected to the fuel cell stack and the hydrogen pump respectively; The air outlet of the air compressor is respectively connected to the intercooler and the switch valve; the air outlet of the air intake combination valve is respectively connected to the air inlet of the humidifier and the air outlet of the switch valve; The fuel cell stack is arranged in a fuel cell stack packaging box; the fuel cell stack packaging box is adapted to the fuel cell stack; the fuel cell stack packaging box is connected to the switch valve; The hydrogen pump is arranged in a hydrogen pump packaging box; the hydrogen pump packaging box is adapted to the hydrogen pump; the hydrogen pump packaging box is connected to the switch valve; The fuel cell system works in a low-temperature cold start heating mode and a fuel cell operation heat dissipation mode: When the fuel cell system works in the low-temperature cold start heating mode, the air compressor is started first, and the air is filtered through the air filter and then compressed by the air compressor to form high-temperature, high-pressure gas. At this time, the intake combination valve is closed, so the gas is not cooled by the intercooler, and the gas temperature is very high; the switch valve is opened, and the high-temperature gas can only flow into the hydrogen pump packaging box and the fuel cell stack packaging box through the switch valve; as the air compressor continues to operate, the temperature of the hydrogen pump and the temperature of the fuel cell stack continue to rise. When the temperature of the hydrogen pump reaches the set temperature T1 and the temperature of the fuel cell stack reaches the set temperature T2, the fuel cell system can be cold started normally; When the fuel cell system is cold-started successfully, the fuel cell stack can output power normally, and the fuel cell system works through the fuel cell operation heat dissipation mode: at this time, the switch valve is closed, and the rear end gas of the air compressor all flows through the intercooler, the air temperature will drop, and the intake combination valve operates normally. The gas with reduced temperature can enter the humidifier through the intake combination valve, and can also enter the hydrogen pump packaging box and the fuel cell stack packaging box after passing through the intake combination valve. This part of the gas is used to continuously cool the hydrogen pump and the fuel cell stack.

2. The fuel cell system using compressed air according to claim 1, characterized in that: The fuel cell system further comprises a water separator and a drain valve. The water separator is respectively connected to the drain valve, the fuel cell stack and the hydrogen pump; the drain valve is respectively connected to the hydrogen pump and the first tail drain.

3. The fuel cell system using compressed air according to claim 2, characterized in that: The water outlet of the fuel cell stack is connected to the water separator and the hydrogen pump respectively.

4. The fuel cell system using compressed air according to claim 1, characterized in that: The fuel cell system further comprises a pressure reducing valve, which is respectively connected to the fuel cell stack, the hydrogen bottle and the hydrogen pump.

5. The fuel cell system using compressed air according to claim 4, characterized in that: The hydrogen inlet of the fuel cell stack is connected to the pressure reducing valve; the gas outlet of the hydrogen pump is connected to the pressure reducing valve and the hydrogen bottle respectively.

6. The fuel cell system using compressed air according to claim 1, characterized in that: The fuel cell system further includes a back pressure valve and a second tail drain, wherein the back pressure valve is connected to the humidifier, the fuel cell stack, and the second tail drain respectively.

7. The fuel cell system using compressed air according to claim 1, characterized in that: The fuel cell stack is a proton exchange membrane fuel cell stack.

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