Integrated fuel cell hydrogen path gas distribution system and fuel cell system

Abstract

The invention discloses an integrated fuel cell hydrogen path gas distribution system and a fuel cell system. The integrated fuel cell hydrogen path gas distribution system comprises a gas-water separator, a hydrogen injection structure is integrated on a shell of the gas-water separator, an injection pipe is arranged on the outer side of a hydrogen outlet of the shell, and the injection pipe is provided with a mixing cavity and a diffusion cavity. An injection cavity is omitted, and a hydrogen return area in the gas-water separator serves as the injection cavity. The ejector assembly, the gas-water separator, the heat exchanger and the gas distribution plate are highly integrated. The number of parts is reduced, and risk points are reduced. The functions of heat exchange, hydrogen supply, gas-water separation and hydrogen return are achieved. The whole design scheme does not have any pipeline connection.

Description

Technical Field

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

[0002] In the hydrogen supply system of the fuel cell system, the requirements for the hydrogen metering ratio are different due to the different working conditions of the fuel cell stack. In order to ensure high efficiency, the hydrogen supply is required to be greater than the hydrogen consumption. During the operation of the fuel cell stack, there must be excess hydrogen that is not consumed. Direct discharge pollutes the environment and is explosive and unsafe. Therefore, a hydrogen circulation system is needed to reuse the excess hydrogen. Among them, the hydrogen ejector is one of the important components in the hydrogen circulation system of the fuel cell. Its main function is to circulate the hydrogen-containing ejector fluid back to the fuel cell for recycling and reuse.

[0003] For example, the utility model with authorization announcement number CN221665005U discloses a hydrogen ejector for a fuel cell, including a hydrogen supply body and an ejector body, wherein one end of the first hydrogen supply channel is connected to the main channel, and the other end is provided with a first ejector nozzle, a second ejector nozzle is provided around the outer periphery of the first ejector nozzle, a second hydrogen supply channel is connected between the first hydrogen supply channel and the second ejector nozzle, an ejector chamber, a mixing chamber and a diffusion chamber are arranged in sequence along the hydrogen flow direction inside the ejector body, one end of the ejector chamber is connected to the first hydrogen supply channel, and the ejector chamber is also provided with a hydrogen return port, characterized in that a gas supply channel is also provided inside the hydrogen supply body, one end of the gas supply channel is connected to the main channel, and the other end is connected to the second hydrogen supply channel, and a gas supply valve for controlling the opening and closing of the gas supply channel is provided on the gas supply channel.

[0004] The excess hydrogen coming out of the fuel cell stack, also known as the anode tail exhaust, is mixed with water produced during the reaction. Before it is returned to the fuel cell stack, a gas-water separator is generally used to separate the gas and water to remove excess water, and then the hydrogen is returned for use.

[0005] For example, the utility model with authorization announcement number CN220939612U discloses a gas-water separator for a fuel cell system, including a gas-water separator body, the gas-water separator body having an inner cavity for gas-water separation, the inner cavity being provided with a horizontal filter baffle which divides the inner cavity into an upper inner cavity and a lower inner cavity, the horizontal filter baffle being provided with a plurality of through holes, and the upper inner cavity being also provided with a plurality of vertical baffles for deflection.

[0006] At present, the gas distribution circuit of the hydrogen subsystem in the fuel cell industry adopts a gas distribution solution that integrates independent components such as heat exchangers, gas distribution systems, ejectors, and gas-water separators. The existing problems are:

[0007] (1) Each component is independent, and the integrated gas distribution circuit is large and bulky. Pipes are required to connect the components, which poses a high risk.

[0008] (2) There are too many parts and each part needs to be designed, processed and verified individually, which is costly. Summary of the invention

[0009] In view of the above-mentioned deficiencies in the prior art, the present invention provides an integrated fuel cell hydrogen gas distribution system and a fuel cell system.

[0010] The design idea is to remove the overlapping parts of the heat exchanger, gas distribution system, ejector and gas-water separator, and integrate the various components into one to achieve an integrated solution. This solution can be regarded as a component, which simplifies the overall design. The layout space and weight are greatly reduced, reducing costs and risks. The elimination of the ejector cavity in the ejector simplifies the design idea.

[0011] The present invention first provides an integrated fuel cell hydrogen gas distribution system, including a gas-water separator, wherein the gas-water separator includes a shell, wherein the shell has an inner cavity for gas-water separation, and one side of the shell is provided with an anode tail exhaust mixed gas inlet for introducing an anode tail exhaust mixed gas into the inner cavity of the gas-water separator, a hydrogen outlet for discharging separated hydrogen, and a water outlet for discharging separated water; the hydrogen outlet is located at an upper part of one side of the inner cavity of the gas-water separator,

[0012] The shell is also integrated with a hydrogen injection structure, which includes a hydrogen supply channel arranged in the shell, the hydrogen supply channel is provided with a hydrogen inlet joint on one side of the shell, and the hydrogen supply channel is provided with an injection nozzle facing the hydrogen outlet in the inner cavity;

[0013] The shell is provided with an ejector pipe on the outside of the hydrogen outlet. The ejector pipe has a mixing chamber connected to the hydrogen outlet and a diffusion chamber away from the hydrogen outlet and with an inner diameter gradually expanding outward. The ejector pipe is used to connect the hydrogen inlet on the fuel cell gas distribution board at the end where the diffusion chamber is located during assembly.

[0014] Preferably, the hydrogen supply channel comprises a main channel and a first hydrogen supply channel, one end of the main channel is provided with the hydrogen inlet connector, and the main channel is provided with a proportional valve;

[0015] One end of the first hydrogen supply channel is connected to the main channel, and the other end is provided with a first injection nozzle. A second injection nozzle is arranged around the outer periphery of the first injection nozzle. A second hydrogen supply channel is connected between the main channel and the second injection nozzle. The second hydrogen supply channel is provided with a solenoid valve.

[0016] Preferably, the shell of the gas-water separator has a fitting surface that fits with the stack end plate of the fuel cell system, and the anode tail exhaust mixed gas inlet is arranged on the fitting surface;

[0017] The hydrogen inlet joint is arranged on the other surface opposite to the bonding surface.

[0018] Preferably, the inner cavity of the gas-water separator has a vertically distributed partition plate, which divides the inner cavity into a separation zone and a hydrogen return zone. The anode tail exhaust mixed gas inlet is located in the separation zone, and the hydrogen outlet is located at the upper part of the hydrogen return zone. A gap is left between the bottom of the partition plate and the bottom surface of the inner cavity for the separated hydrogen and water to pass through.

[0019] The inner cavity has a water storage area below the hydrogen recovery area, and the drain port is located at the bottom surface of the water storage area.

[0020] More preferably, the separation zone has grids spaced apart vertically or diagonally downward.

[0021] More preferably, a portion of the bottom surface of the inner cavity located at the separation area is inclined downward toward the water storage area.

[0022] More preferably, the partition plate and / or the side of the inner cavity is provided with a blocking plate above the water storage area to prevent the hydrogen and water from remixing;

[0023] The blocking plate is arranged obliquely downward from the side of the partition plate or the inner cavity toward the other end.

[0024] More preferably, the anode tail exhaust mixed gas inlet is located in the middle of the separation zone away from the separator plate;

[0025] A through hole connecting the separation zone and the hydrogen return zone is provided on the top of the partition plate.

[0026] Preferably, the shell of the gas-water separator is provided with a mounting hole at the hydrogen outlet, and one end of the ejector tube is provided with a mounting portion, and the mounting portion extends into the mounting hole;

[0027] The opening of the mixing chamber at one end of the mounting portion is connected to the hydrogen outlet. Preferably, the opening is a bell mouth, and the diameter gradually decreases along the gas flow direction, which is conducive to the gas converging to the ejector tube.

[0028] The present invention further provides a fuel cell system, including a fuel cell stack, a gas distribution plate is provided on one side of the fuel cell stack, the gas distribution plate has a hydrogen inlet, the fuel cell stack is also provided with an anode tail exhaust mixed gas outlet, the fuel cell system also includes the integrated fuel cell hydrogen gas path gas distribution system, the ejector pipe is connected to the hydrogen inlet on the fuel cell gas distribution plate at the end where the diffusion chamber is located, and the anode tail exhaust mixed gas inlet is connected to the anode tail exhaust mixed gas outlet.

[0029] Beneficial effects of the present invention:

[0030] The present invention eliminates the ejector assembly and hydrogen preheater, and directly integrates some parts such as proportional valve, solenoid valve and nozzle on the gas-water separator. The ejector connects the gas-water separator and the gas distribution plate into one. The ejector cavity is eliminated, and the hydrogen return area inside the gas-water separator is used as the ejector cavity.

[0031] The ejector assembly, gas-water separator, heat exchanger and gas distribution plate are highly integrated. The number of parts is reduced and the risk points are reduced. The functions of heat exchange, hydrogen supply, gas-water separation and hydrogen return are realized. The entire design scheme has no pipeline connection.

[0032] Since the hydrogen ejection structure is integrated on the gas-water separator, part of the heat in the anode tail exhaust mixed gas can be exchanged with the newly introduced hydrogen from the hydrogen ejection structure through heat transfer, thereby achieving the heat exchange effect of hydrogen. In the present application, since the waste heat in the anode tail exhaust mixed gas is used to heat the newly introduced hydrogen, the newly introduced hydrogen does not need to be preheated by a hydrogen preheater.

[0033] This design method is suitable for all fuel cell hydrogen gas distribution systems. This design method breaks the existing design thinking and makes the integration of fuel cell hydrogen gas distribution systems have a higher design concept. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the three-dimensional structure of the hydrogen gas distribution system of the fuel cell of the present invention.

[0035] Figure 2 It is a schematic cross-sectional view of the hydrogen gas distribution system of a fuel cell according to the present invention.

[0036] Figure 3 It is a cross-sectional view of the gas-water separator of the present invention.

[0037] Figure 4 It is a schematic structural diagram of the inner cavity of the gas-water separator shell of the present invention.

[0038] Figure 5 It is a schematic diagram of the three-dimensional structure of the inner cavity of the shell of the gas-water separator of the present invention.

[0039] Figure 6 It is a structural schematic diagram of the hydrogen injection structure on the gas-water separator of the present invention.

[0040] Reference numerals: gas-water separator 1, shell 101, partition plate 102, separation zone 103, hydrogen return zone 104, anode tail exhaust mixed gas inlet 105, hydrogen outlet 106, water outlet 107, notch 108, water storage area 109, grid 110, blocking plate 111, through hole 112, cover plate 113, hydrogen inlet connector 114, main channel 115, first hydrogen supply channel 116, proportional valve 117, first ejector nozzle 118, second ejector nozzle 119, second hydrogen supply channel 120, solenoid valve 121, drain valve 122,

[0041] Injector tube 2, mixing chamber 201, diffusion chamber 202, mounting portion 203,

[0042] Gas distribution plate 3, hydrogen inlet 301, coolant outlet 302, air outlet 303. DETAILED DESCRIPTION

[0043] like Figures 1 to 6 As shown, an integrated fuel cell hydrogen gas distribution system includes a gas-water separator 1, and the gas-water separator 1 includes a shell 101. The shell 101 has an inner cavity for gas-water separation. One side of the shell 101 is provided with an anode tail exhaust mixed gas inlet 105 for introducing the anode tail exhaust mixed gas into the inner cavity of the gas-water separator 1, a hydrogen outlet 106 for discharging the separated hydrogen, and a water outlet 107 for discharging the separated water.

[0044] The housing 101 of the gas-water separator 1 has a fitting surface that fits with the stack end plate of the fuel cell system, and the anode tail exhaust mixed gas inlet 105 is arranged on the fitting surface. The other side of the gas-water separator 1 opposite to the fitting surface is a detachable cover plate 113.

[0045] like Figure 4 and Figure 5 As shown, the inner cavity structure inside the shell 101 of the gas-water separator 1 after the cover plate 113 is removed.

[0046] The inner cavity of the gas-water separator 1 has a vertically distributed partition plate 102, which divides the inner cavity into a separation zone 103 and a hydrogen return zone 104. The anode tail exhaust mixed gas inlet 105 is located in the separation zone 103, and the hydrogen outlet 106 is located at the upper part of the hydrogen return zone 104. A gap 108 is left between the bottom of the partition plate 102 and the bottom surface of the inner cavity for the separated hydrogen and water to pass through.

[0047] The separation zone 103 has grids 110 that are spaced apart vertically or obliquely downward. In the structure shown in the figure, the grids 110 are spaced apart vertically. The height of the grids 110 is lower than the anode tail exhaust mixed gas inlet 105. The anode tail exhaust mixed gas that enters the inner cavity from the anode tail exhaust mixed gas inlet 105 is first dispersed above the grids 110, and then enters the channel between the grids 110. The mixed gas flows downward under the guidance of the grids 110, and the gas and water are separated under the collision with the grids 110 and the action of its own gravity. The separation scheme combining the grid type and the gravity type is adopted, and the separation effect is good.

[0048] The inner cavity of the shell 101 has a water storage area 109 below the hydrogen recovery area 104, and the drain port 107 is located at the bottom of the water storage area 109. The bottom of the inner cavity located at the separation area 103 is inclined downward toward the water storage area 109, so that the separated water can flow into the water storage area 109.

[0049] The partition plate 102 and / or the side of the inner cavity are provided with a baffle plate 111 above the water storage area 109 to prevent the hydrogen and water from remixing. The baffle plate 111 can be provided on one side of the partition plate 102 or one side of the side of the inner cavity, or both.

[0050] The separation area 103, the water storage area 109 and the hydrogen recovery area 104 are clearly separated, and a baffle plate 111 is designed between the water storage area 109 and the hydrogen recovery area 104 to prevent the separated gas and water from recombining. In addition, the baffle plate 111 is arranged to be inclined downward from the side of the partition plate 102 or the inner cavity to the other end, so that the water droplets condensed on the upper and lower surfaces of the baffle plate 111 can flow downward to the water storage area 109.

[0051] On the outer surface of the shell 101, a drain valve 122 is also provided at the water storage area 109. The drain valve 122 is connected to the drain port 107 for controlling drainage and regularly discharging the water separated and collected in the water storage area 109.

[0052] like Figure 2 and Figure 4 As shown, the anode tail exhaust mixed gas inlet 105 is located in the middle of the separation zone 103 away from the separator 102. A through hole 112 is provided on the top of the separator 102 to connect the separation zone 103 and the hydrogen return zone 104. The anode tail exhaust mixed gas entering the separation zone 103 from the anode tail exhaust mixed gas inlet 105 is divided into two paths. The first path passes through the grid 110 and the gravity separation method to separate the gas and water; the second path goes up to the through hole 112 and separates the gas and water by gravity separation. The two-path design can reduce the hydrogen return flow resistance.

[0053] like Figure 2 , Figure 3 , Figure 6As shown, a hydrogen injection structure is also integrated on the shell 101, and the hydrogen injection structure includes a hydrogen supply channel arranged in the shell 101. The hydrogen supply channel is provided with a hydrogen inlet connector 114 on one side of the shell 101, and the hydrogen inlet connector 114 is provided on the other side opposite to the fitting surface of the shell 101, that is, the side where the cover plate 113 is located.

[0054] The hydrogen supply channel includes a main channel 115 and a first hydrogen supply channel 116. A hydrogen inlet connector 114 is provided at one end of the main channel 115, and a proportional valve 117 is provided at the main channel 115. One end of the first hydrogen supply channel 116 is connected to the main channel 115, and a first ejection nozzle 118 is provided at the other end. A second ejection nozzle 119 is provided around the outer periphery of the first ejection nozzle 118. A second hydrogen supply channel 120 is connected between the main channel 115 and the second ejection nozzle 119, and a solenoid valve 121 is provided at the second hydrogen supply channel 120. The first ejection nozzle 118 and the second ejection nozzle 119 extend into the inner cavity of the housing 101, toward the hydrogen outlet 106.

[0055] The hydrogen inlet connector 114 is connected to the hydrogen supply system, and then the hydrogen enters the first hydrogen supply channel 116 along the main channel 115, wherein the proportional valve 117 provided in the main channel 115 is used to adjust the amount of hydrogen. The hydrogen entering through the main channel 115 is divided into two paths, one path passes through the first hydrogen supply channel 116 and is ejected from the first ejection nozzle 118, and the other path passes through the second hydrogen supply channel 120 and is ejected from the second ejection nozzle 119. The solenoid valve 121 on the second hydrogen supply channel 120 is used to control the amount of hydrogen entering the second ejection nozzle 119, so that the distribution of hydrogen between the first ejection nozzle 118 and the second ejection nozzle 119 can be achieved.

[0056] like Figure 1 , Figure 2 , Figure 6 As shown, the shell 101 is provided with an ejector tube 2 on the outside of the hydrogen outlet 106. The ejector tube 2 has a mixing chamber 201 connected to the hydrogen outlet 106 and a diffusion chamber 202 which is away from the hydrogen outlet 106 and gradually expands from the inner diameter to the outside. The ejector tube 2 is used to connect the hydrogen inlet 301 on the gas distribution plate 3 of the fuel cell at the end where the diffusion chamber 202 is located during assembly.

[0057] The housing 101 of the gas-water separator 1 is provided with a mounting hole at the hydrogen outlet 106, and a mounting portion 203 is provided at one end of the ejector tube 2, and the mounting portion 203 extends into the mounting hole. The opening of the mixing chamber 201 at one end of the mounting portion 203 is connected to the hydrogen outlet 106. Preferably, the opening is a bell mouth, and the diameter gradually decreases along the gas flow direction, which is conducive to the gas converging to the ejector tube 2.

[0058] When the integrated fuel cell hydrogen gas distribution system of the present invention is used in a fuel cell system, Figure 1 and Figure 2As shown, the fuel cell system includes a fuel cell stack (not shown in the figure), a gas distribution plate 3 is provided on one side of the fuel cell stack, the gas distribution plate 3 has a hydrogen inlet 301, and the fuel cell stack is also provided with an anode tail exhaust mixed gas outlet, the ejector tube 2 is connected to the hydrogen inlet 301 on the fuel cell gas distribution plate 3 at the end where the diffusion chamber 202 is located, and the anode tail exhaust mixed gas inlet 105 is connected to the anode tail exhaust mixed gas outlet. The gas distribution plate 3 is also provided with a coolant outlet 302 and an air outlet 303.

[0059] The present invention eliminates the conventional ejector assembly and hydrogen preheater, directly integrates the proportional valve, solenoid valve, nozzle and other components on the gas-water separator 1, and then connects the gas-water separator 1 and the gas distribution plate 3 through an ejector pipe 2. The ejector cavity is eliminated, and the hydrogen return area 104 in the inner cavity of the gas-water separator 1 is used as the ejector cavity. Each component is highly integrated, which reduces the number of components and risk points, and realizes the functions of heat exchange, hydrogen supply, gas-water separation and hydrogen return.

[0060] The temperature of the anode tail exhaust mixed gas discharged from the fuel cell stack is about 80°C, and the inner cavity of the gas-water separator 1 is filled. The temperature of the newly introduced hydrogen from the hydrogen injection structure is at a lower ambient temperature. Since the hydrogen injection structure is integrated into the gas-water separator 1, part of the heat in the anode tail exhaust mixed gas can be exchanged with the newly introduced hydrogen from the hydrogen injection structure through heat transfer, thereby realizing the heat exchange effect of hydrogen. In the prior art, a hydrogen preheater is generally provided, and the coolant exchanges heat with the newly introduced hydrogen in the hydrogen preheater after flowing out of the stack, so as to avoid the production of liquid water after the newly introduced cold hydrogen and the hot hydrogen of the return hydrogen merge. However, in the present application, since the waste heat in the anode tail exhaust mixed gas is used to heat the newly introduced hydrogen, the newly introduced hydrogen does not need to add a hydrogen preheater to preheat the newly introduced hydrogen.

Claims

1. An integrated fuel cell hydrogen gas distribution system, comprising a gas-water separator, the gas-water separator comprising a shell, the shell having an inner cavity for gas-water separation, one side of the shell being provided with an anode tail mixed gas inlet for introducing an anode tail mixed gas into the inner cavity of the gas-water separator, a hydrogen outlet for discharging the separated hydrogen, and a water outlet for discharging the separated water; the hydrogen outlet being located at an upper part of one side of the inner cavity of the gas-water separator, characterized in that The shell is also integrated with a hydrogen injection structure, which includes a hydrogen supply channel arranged in the shell, the hydrogen supply channel is provided with a hydrogen inlet joint on one side of the shell, and the hydrogen supply channel is provided with an injection nozzle facing the hydrogen outlet in the inner cavity; The shell is provided with an ejector pipe on the outside of the hydrogen outlet. The ejector pipe has a mixing chamber connected to the hydrogen outlet and a diffusion chamber away from the hydrogen outlet and with an inner diameter gradually expanding outward. The ejector pipe is used to connect the hydrogen inlet on the fuel cell gas distribution board at the end where the diffusion chamber is located during assembly.

2. The integrated fuel cell hydrogen gas distribution system according to claim 1, characterized in that: The hydrogen supply channel comprises a main channel and a first hydrogen supply channel, one end of the main channel is provided with the hydrogen inlet connector, and the main channel is provided with a proportional valve; One end of the first hydrogen supply channel is connected to the main channel, and the other end is provided with a first injection nozzle. A second injection nozzle is arranged around the outer periphery of the first injection nozzle. A second hydrogen supply channel is connected between the main channel and the second injection nozzle. The second hydrogen supply channel is provided with a solenoid valve.

3. The integrated fuel cell hydrogen gas distribution system according to claim 1, characterized in that: The shell of the gas-water separator has a fitting surface that fits with the stack end plate of the fuel cell system, and the anode tail exhaust mixed gas inlet is arranged on the fitting surface; The hydrogen inlet joint is arranged on the other surface opposite to the bonding surface.

4. The integrated fuel cell hydrogen gas distribution system according to claim 1, characterized in that: The inner cavity of the gas-water separator has a vertically distributed partition plate, which divides the inner cavity into a separation zone and a hydrogen return zone. The anode tail exhaust mixed gas inlet is located in the separation zone, and the hydrogen outlet is located at the upper part of the hydrogen return zone. A gap is left between the bottom of the partition plate and the bottom surface of the inner cavity for the separated hydrogen and water to pass through. The inner cavity has a water storage area below the hydrogen recovery area, and the drain port is located at the bottom surface of the water storage area.

5. The integrated fuel cell hydrogen gas distribution system according to claim 4, characterized in that: The separation zone has grids spaced apart vertically or diagonally downward.

6. The integrated fuel cell hydrogen gas distribution system according to claim 4, characterized in that: The portion of the bottom surface of the inner cavity located at the separation area is inclined downward toward the water storage area.

7. The integrated fuel cell hydrogen gas distribution system according to claim 4, characterized in that: The partition plate and / or the side of the inner cavity are provided with a blocking plate above the water storage area to prevent the hydrogen and water from remixing; The blocking plate is arranged obliquely downward from the side of the partition plate or the inner cavity toward the other end.

8. The integrated fuel cell hydrogen gas distribution system according to claim 4, characterized in that: The anode tail exhaust mixed gas inlet is located in the middle of the separation zone away from the side of the partition plate; A through hole connecting the separation zone and the hydrogen return zone is provided on the top of the partition plate.

9. The integrated fuel cell hydrogen gas distribution system according to claim 1, characterized in that: The shell of the gas-water separator is provided with a mounting hole at the hydrogen outlet, and one end of the ejector tube is provided with a mounting portion, and the mounting portion extends into the mounting hole; The opening of the mixing chamber at one end of the mounting portion is connected to the hydrogen outlet.

10. A fuel cell system, comprising a fuel cell stack, a gas distribution plate is provided on one side of the fuel cell stack, the gas distribution plate has a hydrogen inlet, the fuel cell stack is also provided with an anode tail exhaust mixed gas outlet, characterized in that: The fuel cell system also includes the integrated fuel cell hydrogen gas distribution system according to any one of claims 1 to 9, the ejector pipe is connected to the hydrogen inlet on the fuel cell gas distribution board at the end where the diffusion chamber is located, and the anode tail exhaust mixed gas inlet is connected to the anode tail exhaust mixed gas outlet.

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