Fuel cell hydrogen circulation system

Abstract

The present invention provides a fuel cell hydrogen circulation system, comprising: a hydrogen delivery main road, one end of which is connected to a high-pressure hydrogen cylinder; at least two delivery branches, all of which are led out from the other end of the hydrogen delivery main road and respectively connected to the side of the stack; a circulation loop, which is led out from the bottom of the stack and connected to the hydrogen delivery main road or the delivery branch. The fuel cell hydrogen circulation system provided by the present invention is provided with at least two delivery branches, and all of which are led out from the other end of the hydrogen delivery main road and respectively connected to the side of the stack. Through this arrangement, the flow of the pipeline connecting the inlet of the stack can be greatly reduced, which is more convenient for the selection, adjustment and control of various control valves in the whole system. Moreover, such an arrangement can make the flow of each inlet of the stack more stable, the hydrogen flow distributed to each plate inside the stack more uniform, and the hydrogen flow easier to control.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell hydrogen circulation system. Background Art

[0002] At present, most automotive fuel cell hydrogen circulation systems use 35MPa or 70MPa high-pressure hydrogen storage tanks, which are then decompressed to a suitable pressure range through two or more stages to supply the stack. The fuel cell system mainly includes three major systems: air supply subsystem, hydrogen circulation subsystem and water and heat management subsystem. Among them, the hydrogen circulation subsystem continuously provides high-purity hydrogen with a certain pressure and flow rate to the stack to ensure the normal electrochemical reaction in the fuel cell stack. The hydrogen circulation system ensures the water balance in the fuel cell and improves the economy of the system by recycling a large amount of hydrogen.

[0003] At present, the hydrogen circulation subsystem loop mainly adopts two technical solutions, hydrogen circulation pump and ejector, to realize the recycling of hydrogen. Although there are many hydrogen circulation loop solutions, due to the limitation of the inlet and outlet structure of the fuel cell stack, hydrogen enters the fuel cell stack inlet in a single-inlet and single-outlet form (single fuel cell stack hydrogen inlet for intake, single fuel cell stack hydrogen outlet for exhaust). That is, the hydrogen inlet and outlet of the fuel cell stack are both one, usually hydrogen passes through the common inlet flow channel on one side of the fuel cell stack, and then disperses into the multi-layer bipolar plate hydrogen flow channel in the fuel cell stack, and finally converges to the common outlet flow channel on the other side. This type of loop form puts forward very strict requirements on the control elements in the hydrogen pipeline system when the hydrogen flow rate in the intake pipeline of a high-power fuel cell stack (such as 120kw power) is as high as 2000L / min. Therefore, research on the inlet and outlet flow control and flow distribution of the fuel cell stack is an urgent need currently faced. Summary of the invention

[0004] The present invention provides a fuel cell hydrogen circulation system, which is used to solve the problem in the prior art that the inlet and outlet of the fuel cell stack cannot perform effective flow control and flow distribution, and achieves the effect of facilitating the system to perform flow control.

[0005] The present invention provides a fuel cell hydrogen circulation system, comprising: a hydrogen delivery main path, one end of which is connected to a high-pressure hydrogen cylinder; at least two delivery branches, all of which are led out from the other end of the hydrogen delivery main path and are respectively connected to the side of the fuel cell stack; and a circulation loop, which is led out from the bottom of the fuel cell stack and connected to the hydrogen delivery main path or the delivery branch.

[0006] According to the fuel cell hydrogen circulation system provided by the present invention, the delivery branch includes a first delivery branch and a second delivery branch, wherein the first delivery branch and the second delivery branch are led out from the other end of the hydrogen delivery main path and are respectively connected to two sides of the fuel cell stack.

[0007] According to the fuel cell hydrogen circulation system provided by the present invention, a first solenoid valve is arranged on the hydrogen delivery main line, a second solenoid valve and a first pressure sensor are arranged in sequence on the first delivery branch line, and a second pressure sensor is arranged on the second delivery branch line.

[0008] According to the fuel cell hydrogen circulation system provided by the present invention, one end of the circulation loop is connected to the bottom of the fuel cell stack, and the other end is connected to the hydrogen delivery main line and is located upstream of the first solenoid valve, wherein the circulation loop is sequentially connected with a first three-way solenoid valve, a first water-gas separator, a hydrogen circulation pump and a one-way valve, and the first water-gas separator is connected to a third solenoid valve.

[0009] According to the fuel cell hydrogen circulation system provided by the present invention, a first ejector is arranged on the hydrogen delivery main line, a fourth solenoid valve and a third pressure sensor are arranged in sequence on the first delivery branch line, and a fourth pressure sensor is arranged on the second delivery branch line.

[0010] According to the fuel cell hydrogen circulation system provided by the present invention, one end of the circulation loop is connected to the bottom of the fuel cell stack, and the other end is connected to the first ejector, wherein a second three-way solenoid valve and a second water-gas separator are sequentially connected in the circulation loop, and a fifth solenoid valve is connected to the second water-gas separator.

[0011] According to the fuel cell hydrogen circulation system provided by the present invention, a sixth solenoid valve, a second ejector and a fifth pressure sensor are sequentially arranged on the first delivery branch, and a third ejector and a sixth pressure sensor are sequentially arranged on the second delivery branch.

[0012] According to the fuel cell hydrogen circulation system provided by the present invention, one end of the circulation loop is connected to the bottom of the fuel cell stack, and the other end is respectively connected to the second ejector and the third ejector, wherein the third three-way solenoid valve and the third water-gas separator are sequentially connected in the circulation loop, and the seventh solenoid valve is connected to the third water-gas separator.

[0013] According to the fuel cell hydrogen circulation system provided by the present invention, in the main hydrogen delivery path, a first gas cylinder inlet regulating valve, a first high-pressure pressure reducing valve, a seventh pressure sensor, a first low-pressure pressure reducing valve and an eighth pressure sensor are sequentially connected between the high-pressure hydrogen cylinder and the other end of the circulation loop.

[0014] According to the fuel cell hydrogen circulation system provided by the present invention, a second gas cylinder inlet regulating valve, a second high-pressure reducing valve, a ninth pressure sensor, a second low-pressure reducing valve, a tenth pressure sensor and an eighth solenoid valve are sequentially connected in the hydrogen delivery main path.

[0015] The fuel cell hydrogen circulation system provided by the present invention is provided with at least two delivery branches, and all the delivery branches are led out from the other end of the hydrogen delivery main road and are respectively connected to the side of the stack. Through this arrangement, the flow of the pipeline connecting the inlet of the stack can be greatly reduced, which is more convenient for the selection, adjustment and control of various control valves in the whole system. Moreover, such an arrangement can make the flow of each inlet of the stack more stable, the hydrogen flow distributed to each plate inside the stack more uniform, and the hydrogen flow is easier to control. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 This is one of the structural schematic diagrams of the fuel cell hydrogen circulation system provided by the present invention;

[0018] Figure 2 This is the second structural schematic diagram of the fuel cell hydrogen circulation system provided by the present invention;

[0019] Figure 3 This is the third structural schematic diagram of the fuel cell hydrogen circulation system provided by the present invention;

[0020] Reference numerals:

[0021] 100: fuel cell hydrogen circulation system; 102: hydrogen transportation main line;

[0022] 104: first transmission branch; 106: second transmission branch;

[0023] 108: circulation loop; 110: first solenoid valve;

[0024] 112: second solenoid valve; 114: first pressure sensor;

[0025] 116: a second pressure sensor; 118: a first three-way solenoid valve;

[0026] 120: first water-gas separator; 122: hydrogen circulation pump;

[0027] 124: one-way valve; 126: third solenoid valve;

[0028] 128: a first ejector; 130: a fourth solenoid valve;

[0029] 132: a third pressure sensor; 134: a fourth pressure sensor;

[0030] 136: second three-way solenoid valve; 138: second water-gas separator;

[0031] 140: fifth solenoid valve; 142: sixth solenoid valve;

[0032] 144: a second ejector; 146: a fifth pressure sensor;

[0033] 148: a third ejector; 150: a sixth pressure sensor;

[0034] 152: third three-way solenoid valve; 154: third water-gas separator;

[0035] 156: the seventh solenoid valve; 158: the first gas cylinder inlet regulating valve;

[0036] 160: a first high pressure reducing valve; 162: a seventh pressure sensor;

[0037] 164: a first low-pressure pressure reducing valve; 166: an eighth pressure sensor;

[0038] 168: Second gas cylinder inlet regulating valve; 170: Second high-pressure pressure reducing valve;

[0039] 172: ninth pressure sensor; 174: second low-pressure pressure reducing valve;

[0040] 176: tenth pressure sensor; 178: eighth solenoid valve;

[0041] 200: High-pressure hydrogen tank; 300: Fuel cell. DETAILED DESCRIPTION

[0042] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0043] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0044] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0045] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the 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, the first feature being "above", "above" and "above" the 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. The first feature being "below", "below" and "below" the 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.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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 embodiment 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 specific features, structures, materials or characteristics described 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.

[0047] Combine the following Figures 1 to 3 The fuel cell hydrogen circulation system 100 of the present invention is described. It should be understood that the following description is only an exemplary embodiment of the present invention and does not constitute any particular limitation to the present invention.

[0048] According to an embodiment of the present invention, a fuel cell hydrogen circulation system 100 is provided. The fuel cell hydrogen circulation system 100 includes a hydrogen delivery main path 102 , at least two delivery branches and a circulation loop 108 .

[0049] Specifically, one end of the hydrogen transport main path 102 is connected to the high-pressure hydrogen cylinder 200, and all the transport branches are led out from the other end of the hydrogen transport main path 102 and respectively connected to the side of the stack 300. The circulation loop 108 is led out from the bottom of the stack 300 and connected to the hydrogen transport main path 102 or the transport branch.

[0050] According to the above embodiments of the present invention, in the fuel cell hydrogen circulation system 100 provided in the embodiment of the present invention, at least two delivery branches are provided, and all delivery branches are led out from the other end of the hydrogen delivery main road 102 and are respectively connected to the side of the stack 300. Through this arrangement, the flow of the pipeline connecting the inlet of the stack can be greatly reduced, which is more convenient for the selection, adjustment and control of various control valves in the whole system. Moreover, such an arrangement can make the flow of each inlet of the stack more stable, the hydrogen flow distributed to each plate inside the stack more uniform, and the hydrogen flow is easier to control.

[0051] In one embodiment of the present invention, the delivery branch may include a first delivery branch 104 and a second delivery branch 106. Specifically, the first delivery branch 104 and the second delivery branch 106 are led out from the other end of the hydrogen delivery main path 102 as described above and are respectively connected to both sides of the fuel cell stack 300. In actual application, by designing the structure of the fuel cell stack 300, an isolation baffle is set in the middle part of the fuel cell stack 300, and the original common hydrogen flow channel of the fuel cell stack 300 is changed to an inlet flow channel at both ends. By setting the first delivery branch 104 and the second delivery branch 106, the flow rate of the two inlets of the fuel cell stack 300 is reduced to 1 / 2 of the original single inlet flow rate.

[0052] It can be seen that in the fuel cell hydrogen circulation system 100 provided in the embodiment of the present invention, the system shares one outlet flow channel (i.e., circulation loop 108) and includes two inlet flow channels (i.e., first delivery branch 104 and second delivery branch 106), thereby completing the design of a double-inlet and single-outlet stack. In this way, the flow rates of the two inlets of the stack 300 are reduced by half, which facilitates the system flow control.

[0053] The following describes the specific implementation of the fuel cell hydrogen circulation system 100 provided by the present invention in combination with different embodiments. It should be understood that the following is only an illustrative implementation of the present invention and does not constitute any limitation to the present invention. It should also be understood that in actual use, the user can select any of the following implementations for operation as needed.

[0054] like Figure 1 As shown, in one embodiment of the present invention, a first solenoid valve 110 is provided on the hydrogen delivery main path 102 , a second solenoid valve 112 and a first pressure sensor 114 are provided in sequence on the first delivery branch 104 , and a second pressure sensor 116 is provided on the second delivery branch 106 .

[0055] In addition, for the circulation loop 108, one end of the circulation loop 108 can be connected to the bottom of the stack 300, and the other end is connected to the hydrogen delivery main path 102 and is located upstream of the first solenoid valve 110. Specifically, the circulation loop 108 can be connected in sequence with the first three-way solenoid valve 118, the first water-gas separator 120, the hydrogen circulation pump 122 and the one-way valve 124, and the first water-gas separator 120 is connected with the third solenoid valve 126.

[0056] Furthermore, in the hydrogen delivery main path 102, the first gas cylinder inlet regulating valve 158, the first high-pressure pressure reducing valve 160, the seventh pressure sensor 162, the first low-pressure pressure reducing valve 164 and the eighth pressure sensor 166 are sequentially connected between the high-pressure hydrogen cylinder 200 and the other end of the circulation loop 108. In other words, the other end of the circulation loop 108 is located between the eighth pressure sensor 166 and the first solenoid valve 110 in the hydrogen delivery main path 102.

[0057] Thus, the formation Figure 1 The first embodiment of the fuel cell hydrogen circulation system 100 of the present invention is shown.

[0058] like Figure 2 As shown, in another embodiment of the present invention, Figure 1 The embodiment shown is different in that a first ejector 128 may be provided on the hydrogen delivery main path 102. A fourth solenoid valve 130 and a third pressure sensor 132 are provided in sequence on the first delivery branch 104, and a fourth pressure sensor 134 is provided on the second delivery branch 106.

[0059] In addition, for the circulation loop 108, one end of the circulation loop 108 is connected to the bottom of the stack 300, and the other end can be connected to the first ejector 128. Specifically, the second three-way solenoid valve 136 and the second water-gas separator 138 can be connected in sequence in the circulation loop 108, and the fifth solenoid valve 140 can be connected to the second water-gas separator 138.

[0060] like Figure 3 As shown, in another embodiment of the present invention, Figure 1 and Figure 2 What is different from the illustrated embodiment is that a sixth solenoid valve 142 , a second ejector 144 and a fifth pressure sensor 146 may be sequentially disposed on the first delivery branch 104 , while a third ejector 148 and a sixth pressure sensor 150 may be sequentially disposed on the second delivery branch 106 .

[0061] In addition, for the circulation loop 108, one end of the circulation loop 108 can be connected to the bottom of the stack 300, and the other end can be respectively connected to the second ejector 144 and the third ejector 148. Specifically, the third three-way solenoid valve 152 and the third water-gas separator 154 can be connected in sequence in the circulation loop 108, and the seventh solenoid valve 156 can be connected to the third water-gas separator 154.

[0062] for Figure 2 and Figure 3 In the embodiment shown, a second gas cylinder inlet regulating valve 168, a second high-pressure reducing valve 170, a ninth pressure sensor 172, a second low-pressure reducing valve 174, a tenth pressure sensor 176 and an eighth solenoid valve 178 may also be connected in sequence in the hydrogen delivery main path 102.

[0063] Among them, for Figure 2 For the embodiment shown, the eighth solenoid valve 178 may be located upstream of the first ejector 128, thereby forming a Figure 2 The structure shown; and for Figure 3 In the embodiment shown in the figure, the first delivery branch 104 and the second delivery branch 106 are directly led out downstream of the eighth solenoid valve 178, thereby forming the following Figure 3 The structure shown.

[0064] In summary, in the fuel cell hydrogen circulation system 100 provided in the embodiment of the present invention, since multiple delivery branches (for example, the first delivery branch 104 and the second delivery branch 106) are provided, the flow rate of the pipeline connecting the inlet of the stack can be greatly reduced, which is more convenient for the selection, adjustment and control of various control valves in the whole system. Moreover, such a setting can make the flow rate of each inlet of the stack more stable, the hydrogen flow rate distributed to each plate inside the stack more uniform, and the hydrogen flow rate is easier to control.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fuel cell hydrogen circulation system, characterized in that: include: A main hydrogen transportation path, one end of which is connected to a high-pressure hydrogen cylinder; At least two transport branches, all of which are led out from the other end of the hydrogen transport main road and are respectively connected to the side of the fuel cell stack; A circulation loop, the circulation loop is led out from the bottom of the fuel cell stack and connected to the hydrogen transportation main path or the transportation branch path; The delivery branch includes a first delivery branch and a second delivery branch, The first delivery branch and the second delivery branch are led out from the other end of the hydrogen delivery main path and are connected to two sides of the fuel cell stack respectively, and An isolation baffle is provided in the middle of the battery stack; The hydrogen delivery main line is provided with a first solenoid valve, the first delivery branch line is provided with a second solenoid valve and a first pressure sensor in sequence, and the second delivery branch line is provided with a second pressure sensor; One end of the circulation loop is connected to the bottom of the fuel cell stack, and the other end is connected to the main hydrogen delivery path and is located upstream of the first solenoid valve. Wherein, the circulation loop is sequentially connected with a first three-way solenoid valve, a first water-gas separator, a hydrogen circulation pump and a one-way valve, and the first water-gas separator is connected with a third solenoid valve.

2. The fuel cell hydrogen circulation system according to claim 1, characterized in that: The hydrogen delivery main line is provided with a first ejector, the first delivery branch line is provided with a fourth solenoid valve and a third pressure sensor in sequence, and the second delivery branch line is provided with a fourth pressure sensor.

3. The fuel cell hydrogen circulation system according to claim 2, characterized in that: One end of the circulation loop is connected to the bottom of the battery stack, and the other end is connected to the first ejector. Wherein, the circulation loop is sequentially connected with a second three-way solenoid valve and a second water-gas separator, and the second water-gas separator is connected with a fifth solenoid valve.

4. The fuel cell hydrogen circulation system according to claim 1, characterized in that: The first delivery branch is provided with a sixth solenoid valve, a second ejector and a fifth pressure sensor in sequence, and the second delivery branch is provided with a third ejector and a sixth pressure sensor in sequence.

5. The fuel cell hydrogen circulation system according to claim 4, characterized in that: One end of the circulation loop is connected to the bottom of the battery stack, and the other end is connected to the second ejector and the third ejector respectively. Wherein, the circulation loop is sequentially connected with a third three-way solenoid valve and a third water-gas separator, and the third water-gas separator is connected with a seventh solenoid valve.

6. The fuel cell hydrogen circulation system according to claim 1, characterized in that: In the main hydrogen delivery path, a first gas cylinder inlet regulating valve, a first high-pressure pressure reducing valve, a seventh pressure sensor, a first low-pressure pressure reducing valve and an eighth pressure sensor are sequentially connected between the high-pressure hydrogen cylinder and the other end of the circulation loop.

7. The fuel cell hydrogen circulation system according to claim 3 or 4, characterized in that: The second gas cylinder inlet regulating valve, the second high-pressure pressure reducing valve, the ninth pressure sensor, the second low-pressure pressure reducing valve, the tenth pressure sensor and the eighth solenoid valve are sequentially connected to the hydrogen delivery main path.

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