Reactive gas redistribution structure of fuel cell stack

Abstract

The invention discloses a fuel cell stack reaction gas redistribution structure, and relates to the technical field of fuel cells, the fuel cell stack reaction gas redistribution structure comprises an electric pile assembly and a gas-water separator, the electric pile assembly comprises a fuel cell, a first connecting piece and a second connecting piece, and the two ends of the fuel cell are connected to the first connecting piece and the second connecting piece respectively; the gas inlet end of the first connecting piece is used for being connected with a reaction gas supply source. The air inlet end of the air-water separator is connected with the air outlet end of the first connecting piece, the air outlet end of the air-water separator is connected with the air inlet end of the second connecting piece, and the air outlet end of the second connecting piece is used for being connected with the air inlet end of another air-water separator. A gas-water separator is connected between every two adjacent fuel cells, the gas-water separator can separate and discharge water in gas-water mixed fluid after the reaction of the previous fuel cell, the water content of gas flowing into the next fuel cell is low, and the electrode side of the subsequent fuel cell cannot be flooded; and the gas can be continuously used by the next fuel cell, so that energy is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell stack reaction gas redistribution structure. Background Art

[0002] A fuel cell is a chemical device that converts the chemical energy of a fuel directly into electrical energy. It is also called an electrochemical generator. It is the fourth power generation technology after hydroelectric power generation, thermal power generation, and atomic power generation. Since fuel cells convert part of the Gibbs free energy in the chemical energy of a fuel into electrical energy through electrochemical reactions, they are not limited by the Carnot cycle effect and therefore have high efficiency. In addition, fuel cells use fuel and oxygen as raw materials and have no mechanical transmission parts, so they emit very little harmful gas and have a long service life. It can be seen that from the perspective of energy conservation and ecological protection, fuel cells are the most promising power generation technology.

[0003] In order to increase the battery capacity, multiple fuel cells can be connected in series to form a stack. During operation, the reaction gas is passed into each battery in turn so that each battery can generate electricity. However, since each battery is directly connected in series, water will be generated after the battery reacts with the reaction gas. After the reaction gas passes through the front battery, it will be mixed with water; when the mixture of reaction gas and water passes through the battery behind the stack, it is easy to cause water flooding on the anode side of the rear battery, thereby affecting the stability and life of the fuel cell. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned technical deficiencies and propose a fuel cell stack reaction gas redistribution structure to solve the technical problem in the prior art that the mixture of the reaction gas and water of the fuel cell is easily flooded on the anode side of the rear battery when passing through the rear battery of the stack, thereby affecting the stability and life of the fuel cell.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: The present invention provides a fuel cell stack reaction gas redistribution structure, comprising: A fuel cell stack assembly, comprising a fuel cell, a first connector and a second connector, wherein two ends of the fuel cell are respectively connected to the first connector and the second connector, and an air inlet end of the first connector is used to connect to a reactant gas supply source; and An air-water separator, wherein the air inlet end of the air-water separator is connected to the air outlet end of the first connecting piece, the air outlet end of the air-water separator is connected to the air inlet end of the second connecting piece, and the air outlet end of the second connecting piece is used to connect to the air inlet end of another air-water separator.

[0006] In some embodiments, the first connector and the second connector have the same structure, and plug-in components are disposed on both sides of the first connector, and the plug-in components are detachably connected to the fuel cell.

[0007] In some embodiments, a hydrogen inlet channel and a hydrogen outlet channel are respectively formed at both ends of the first connecting member, the hydrogen inlet channel is connected to the inlet of the hydrogen channel of the fuel cell, and the hydrogen outlet channel is connected to the outlet of the hydrogen channel of the fuel cell.

[0008] In some embodiments, an oxygen inlet channel and an oxygen outlet channel are respectively formed at both ends of the first connecting member, wherein the oxygen inlet channel is connected to the inlet of the oxygen channel of the fuel cell, and the oxygen outlet channel is connected to the outlet of the oxygen channel of the fuel cell.

[0009] In some embodiments, the gas-water separator includes a first separation unit, which includes a shell and a centrifugal mechanism arranged inside the shell, the shell has a gas-water inlet, a gas outlet and a liquid outlet, the gas inlet is connected to the gas outlet of the fuel cell, the gas outlet is connected to the gas inlet of the second connecting member, and the liquid outlet is used to discharge the liquid separated by the centrifugal mechanism.

[0010] In some embodiments, the gas-water separator also includes a second separation unit, the structure of the second separation unit is consistent with that of the first separation unit, the gas-water inlet of the first separation unit is connected to the hydrogen outlet channel of the first connecting piece, the gas-water outlet of the first separation unit is connected to the hydrogen inlet channel of the second connecting piece, the gas-water inlet of the second separation unit is connected to the oxygen outlet channel of the first connecting piece, and the gas outlet of the second separation unit is connected to the oxygen inlet channel of the second connecting piece.

[0011] In some embodiments, a connected centrifugal chamber and a gas chamber are provided in the shell, the gas chamber is located above the centrifugal chamber, the gas-water inlet is connected to the top of the centrifugal chamber, the liquid outlet is connected to the bottom of the centrifugal chamber, and the gas outlet is connected to the top of the gas chamber.

[0012] In some embodiments, the centrifugal mechanism includes a motor and a separation paddle connected to each other, the motor is connected to the shell and is located outside the shell, the separation paddle is rotatably arranged in the centrifugal chamber, and the motor can drive the separation paddle to rotate to centrifugally separate the gas and water entering the centrifugal chamber through the gas-water inlet.

[0013] In some embodiments, the separation paddle includes a rotating rod and a plurality of water blocking plates, and the plurality of water blocking plates are arranged at intervals along the length direction of the rotating rod.

[0014] In some embodiments, the separation paddle further comprises a plurality of liquid anti-rotation plates, and the plurality of liquid anti-rotation plates are all located at the bottom of the rotating rod and are evenly arranged around the circumference of the rotating rod.

[0015] Compared with the prior art, the fuel cell stack reaction gas redistribution structure provided by the present invention can connect multiple fuel cells included in the stack assembly end to end through the first connector and the second connector to enhance the stability of the connection of multiple fuel cells. A gas-water separator is connected between two adjacent fuel cells, and the gas-water separator can separate and discharge the water in the gas-water mixed fluid after the reaction of the previous fuel cell. The water content of the gas flowing into the next fuel cell is small, and the electrode side of the subsequent fuel cell will not be flooded. The gas can also be used by the next fuel cell, which is conducive to saving energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a structural schematic diagram of a fuel cell stack reaction gas redistribution structure according to an embodiment of the present invention; Figure 2 is a cross-sectional schematic diagram of a first connecting member provided by an embodiment of the present invention; Figure 3 is a cross-sectional schematic diagram of a gas-water separator provided by an embodiment of the present invention; Figure 4 is a structural schematic diagram of a centrifugal mechanism provided in an embodiment of the present invention; Figure 5 It is a structural schematic diagram of a fuel cell stack reaction gas redistribution structure according to another embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In order to solve the technical problem that the mixture of the reaction gas and water of the fuel cell is prone to flooding the anode side of the rear cell when passing through the rear cell of the stack, thereby affecting the stability and life of the fuel cell, the present invention provides a fuel cell stack reaction gas redistribution structure, which can enhance the stability of the connection of multiple fuel cells connected in series and discharge the moisture in the gas-water mixed fluid of the previous fuel cell to avoid flooding the electrode side of the next fuel cell.

[0019] See also Figure 1 , Figure 1This is a structural schematic diagram of a fuel cell stack reaction gas redistribution structure in an embodiment of the present invention. The fuel cell stack reaction gas redistribution structure includes a stack assembly 1 and a gas-water separator 2. The stack assembly 1 includes a fuel cell 11, a first connecting member 12 and a second connecting member 13. Both ends of the fuel cell 11 are respectively connected to the first connecting member 12 and the second connecting member 13. The air inlet end of the first connecting member 12 is used to connect to a reaction gas supply source. The reaction gas supply source includes a hydrogen supply source and an oxygen supply source. The hydrogen supply source is used to provide the fuel cell with hydrogen required for the reaction, and the oxygen supply source is used to provide the fuel cell with oxygen required for the reaction.

[0020] The air inlet of the gas-water separator 2 is connected to the air outlet of the first connector 12, and the air outlet of the gas-water separator 2 is connected to the air inlet of the second connector 13. The air outlet of the second connector 13 is used to connect to the air inlet of another gas-water separator 2. Similarly, the shells of multiple fuel cells 11 are connected end to end through the first connector 12 and the second connector 13 to enhance the strength of the connection structure between the multiple fuel cells 11. The gas pipelines of multiple fuel cells 11 are connected through the gas-water separator 2. The residual gas discharged after the reaction of the previous fuel cell 11 will be mixed with a certain amount of water. In order to avoid the influence of flooding on the electrode side of the next fuel cell 11, a gas-water separator 2 is set between adjacent fuel cells 11 to remove the water in the residual gas discharged from the previous fuel cell 11. The residual gas enters the next fuel cell 11 for secondary use, which is conducive to saving energy.

[0021] In one embodiment, see Figure 1 and Figure 2 The first connector 12 and the second connector 13 have the same structure. Connectors 14 are provided on both sides of the first connector 12 and the second connector 13. The connectors 14 are detachably connected to the fuel cell 11, so that multiple fuel cells 11 can be connected end to end through the connectors 14 of the first connector 12 and the second connector 13, and it is also convenient to disassemble and assemble to increase or decrease the number of fuel cells 11.

[0022] In one embodiment, see Figure 2, a hydrogen inlet channel 121 and a hydrogen outlet channel 122 are respectively provided at both ends of the first connecting member 12. As is well known, the fuel cell 11 itself has a hydrogen channel and an oxygen channel, and the hydrogen channel and the oxygen channel are used to supply hydrogen and oxygen for circulation, respectively, so as to facilitate the use of the fuel cell for power generation. The hydrogen inlet channel 121 is connected to the inlet of the hydrogen channel of the fuel cell 11, and the hydrogen outlet channel is connected to the outlet of the hydrogen channel of the fuel cell. In this embodiment, when the first connecting member 12 is connected to a hydrogen supply source, the hydrogen supply source can input hydrogen into the hydrogen inlet channel 121 of the first connecting member 12, so that hydrogen enters the hydrogen channel of the fuel cell through the hydrogen inlet channel 121. The hydrogen channel of the fuel cell is roughly U-shaped (refer to Figure 1 The hydrogen passes through the U-shaped hydrogen channel and can fully react with the oxygen in the fuel cell, and then is discharged from the outlet of the hydrogen channel, and is discharged through the hydrogen outlet channel 122 of the first connecting member 12 to the gas-water separator 2. The gas-water separator 2 removes the water in the remaining hydrogen, and then passes through the hydrogen inlet channel 121 of the second connecting member 13, and enters the hydrogen channel of the next fuel cell through the hydrogen inlet channel 121. By analogy, the hydrogen can be continuously used without the need to configure a separate hydrogen supply source for each fuel cell, which greatly improves the working efficiency of the fuel cell and saves costs.

[0023] In one embodiment, see Figure 2 In some embodiments, an oxygen inlet channel 123 and an oxygen outlet channel 124 are respectively provided at both ends of the first connecting member 12. The oxygen inlet channel 123 is connected to the inlet of the oxygen channel of the fuel cell 11, and the oxygen outlet channel is connected to the outlet of the oxygen channel of the fuel cell. In the present embodiment, when the first connecting member 12 is connected to the oxygen supply source, the oxygen supply source can input oxygen into the oxygen inlet channel 123 of the first connecting member 12, so that the oxygen enters the oxygen channel of the fuel cell 11 through the oxygen inlet channel 123. The oxygen channel of the fuel cell is roughly U-shaped. The oxygen can fully react with the hydrogen in the fuel cell 11 through the U-shaped oxygen channel, and then be discharged from the outlet of the oxygen channel, and be discharged through the oxygen outlet channel 124 of the first connecting member 12 to the gas-water separator 2. The gas-water separator 2 removes moisture from the remaining oxygen, and then passes it into the oxygen inlet channel 123 of the second connecting member 13, and enters the oxygen channel of the next fuel cell 11 through the oxygen inlet channel 123. By analogy, the oxygen can be continuously used without the need to configure a separate oxygen supply source for each fuel cell 11, which greatly improves the working efficiency of the fuel cell and saves costs.

[0024] In one embodiment, the gas-water separator 2 includes a first separation unit, which includes a shell 21 and a centrifugal mechanism 22 disposed inside the shell 21. The shell 21 has a gas-water inlet 211, a gas outlet 212 and a liquid outlet 213. The gas inlet 211 is connected to the gas outlet of the fuel cell 11, specifically connected to the hydrogen outlet channel 122 of the first connector 12, so that the remaining hydrogen after the fuel cell reaction enters the shell 21. The hydrogen contains more water. The gas outlet 212 is connected to the gas inlet of the second connector 13, specifically connected to the hydrogen inlet channel 121 of the second connector 13, so that the hydrogen with less water content separated by the centrifugal mechanism 22 can enter the hydrogen inlet channel 121 of the second connector 13, and then enter the next fuel cell through the hydrogen inlet channel 121, so that the hydrogen continues to be used. The liquid outlet 213 is used to discharge the liquid separated by the centrifugal mechanism 22 to prevent the liquid from following the hydrogen into the next fuel cell and causing flooding on the electrode side.

[0025] In some embodiments, the gas-water separator 2 further includes a second separation unit, which has the same structure as the first separation unit, and the gas-water inlet 211 of the second separation unit is connected to the oxygen outlet channel 124 of the first connector 12, for receiving the remaining oxygen after the fuel cell reaction, which contains a lot of water. The gas outlet 212 of the second separation unit is connected to the oxygen inlet channel 123 of the second connector 13, so that the oxygen with less water content separated by the centrifugal mechanism 22 can enter the oxygen inlet channel 123 of the second connector 13, and then enter the next fuel cell through the oxygen inlet channel 123, so that the oxygen can continue to be used.

[0026] The first separation unit and the second separation unit are both independent structures and do not interfere with each other. The first separation unit is used to separate water from hydrogen, and the second separation unit is used to separate water from oxygen.

[0027] In one embodiment, see Figure 3 and Figure 4 In some embodiments, the housing 21 is provided with a connected centrifugal chamber 214 and a gas chamber 215, the gas chamber 215 is located above the centrifugal chamber 214, the gas-water inlet 211 is connected to the top of the centrifugal chamber 214, the liquid outlet 213 is connected to the bottom of the centrifugal chamber 214, and the gas outlet 212 is connected to the top of the gas chamber 215. The centrifugal mechanism 22 includes a motor 221 and a separation paddle 222 connected to each other, the motor 221 is connected to the housing 21 and is located outside the housing 211, the separation paddle 222 is rotatably arranged in the centrifugal chamber 214, the motor 221 can drive the separation paddle 222 to rotate to centrifugally separate the gas and water entering the centrifugal chamber 214 from the gas-water inlet 211, the gas is discharged through the gas outlet 212, and the liquid is discharged from the liquid outlet 213.

[0028] In this embodiment, the housing 21 is set to an inverted L-shaped structure, which is conducive to reducing the rotation speed of the airflow, and can also increase the contact area between the inner wall of the housing 21 and the gas-water mixed fluid, accelerate the condensation of the gas-water mixed fluid, and improve the separation efficiency of the gas-water mixed fluid. At the same time, the cavity wall of the centrifugal cavity is set to an inclined channel, which can redirect the sliding liquid water to the bottom of the centrifugal cavity. The centrifugal cavity 214 is designed to be slender, so that the height-to-diameter ratio (ratio of height to diameter) reaches more than 3. Compared with the centrifugal cavity 214 with a height-to-diameter ratio of less than 3, the resistance is smaller, which is conducive to improving the working flow.

[0029] The separation paddle 222 includes a rotating rod 223 and a plurality of water baffles 224, and the plurality of water baffles 224 are arranged at intervals along the length direction of the rotating rod 222. The separation paddle 222 also includes a plurality of liquid anti-rotation plates 225, and the plurality of liquid anti-rotation plates 225 are all located at the bottom of the rotating rod 223 and are evenly arranged around the circumference of the rotating rod 223.

[0030] The gas-water mixed fluid enters the centrifugal chamber 214 from the gas-water inlet 211; the motor 221 drives the rotating rod 223 to rotate, and the rotating rod 223 drives multiple water baffles 224 and liquid anti-rotation plates 225 to rotate, and the gas-water mixed fluid performs centrifugal motion in the centrifugal chamber 214. The strong centrifugal force will drive the liquid water to drip along the inner wall of the centrifugal chamber 214; the liquid water falls with a large rotation speed, and after passing the last water baffle 224, it enters the bottom liquid anti-rotation plate 225, gradually reducing the rotation speed of the liquid water, and finally the liquid water is discharged from the liquid outlet 213. During the centrifugal motion of the gas-water mixed fluid in the centrifugal chamber 214, most of the gas will not move to the bottom of the centrifugal chamber 214, but spirally rise and enter the gas chamber 215; the high-speed moving gas hits the gas baffle 216 in the gas chamber 215, and the gas movement speed is reduced, and finally the gas is discharged from the gas outlet 212. The gas baffle 216 has the function of reducing the gas movement speed and accelerating the condensation of gaseous water. The small droplets and condensed water gradually slide down the gas baffle 216 and flow toward the centrifugal chamber 214 .

[0031] See also Figure 5 , Figure 5 The illustrated embodiment shows that a plurality of fuel cells 11 are connected end to end through a plurality of first connectors 12 and second connectors 13 to enhance the stability of the connection of the plurality of fuel cells 11. The plurality of first connectors 12 and second connectors 13 are connected through a gas-water separator 2 to remove most of the water in the hydrogen and oxygen exhausted from the previous fuel cell 11, thereby avoiding flooding of the electrode side when the remaining hydrogen and oxygen are used by the next fuel cell.

[0032] In order to better understand the present invention, the following Figures 1 to 5 The technical solution of the present invention is described in detail: In the fuel cell stack reaction gas redistribution structure provided by the present invention, the multiple fuel cells 11 included in the stack assembly can be connected end to end through the first connector 12 and the second connector 13 to enhance the stability of the connection of the multiple fuel cells 11. A gas-water separator 2 is connected between two adjacent fuel cells 11. The gas-water separator 2 can separate and discharge the water in the gas-water mixed fluid after the reaction of the previous fuel cell 11. The water content of the gas flowing into the next fuel cell 11 is small, and the electrode side of the subsequent fuel cell 11 will not be flooded. The residual gas can also be used by the next fuel cell 11, which is conducive to saving energy.

[0033] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A fuel cell stack reaction gas redistribution structure, characterized in that: include: A fuel cell stack assembly, comprising a fuel cell, a first connector and a second connector, wherein two ends of the fuel cell are respectively connected to the first connector and the second connector, and an air inlet end of the first connector is used to connect to a reactant gas supply source; and An air-water separator, wherein the air inlet end of the air-water separator is connected to the air outlet end of the first connecting piece, the air outlet end of the air-water separator is connected to the air inlet end of the second connecting piece, and the air outlet end of the second connecting piece is used to connect to the air inlet end of another air-water separator.

2. The fuel cell stack reaction gas redistribution structure according to claim 1, characterized in that: The first connecting member and the second connecting member have the same structure. Connectors are provided on both sides of the first connecting member. The connectors are detachably connected to the fuel cell.

3. The fuel cell stack reaction gas redistribution structure according to claim 2, characterized in that: A hydrogen inlet channel and a hydrogen outlet channel are respectively provided at both ends of the first connecting member. The hydrogen inlet channel is connected to the inlet of the hydrogen channel of the fuel cell, and the hydrogen outlet channel is connected to the outlet of the hydrogen channel of the fuel cell.

4. The fuel cell stack reaction gas redistribution structure according to claim 3, characterized in that: An oxygen inlet channel and an oxygen outlet channel are respectively formed at two ends of the first connecting member. The oxygen inlet channel is connected to the inlet of the oxygen channel of the fuel cell, and the oxygen outlet channel is connected to the outlet of the oxygen channel of the fuel cell.

5. The fuel cell stack reaction gas redistribution structure according to claim 1, characterized in that: The gas-water separator includes a first separation unit, which includes a shell and a centrifugal mechanism arranged inside the shell, the shell has a gas-water inlet, a gas outlet and a liquid outlet, the gas inlet is connected to the gas outlet of the fuel cell, the gas outlet is connected to the gas inlet of the second connecting piece, and the liquid outlet is used to discharge the liquid separated by the centrifugal mechanism.

6. The fuel cell stack reaction gas redistribution structure according to claim 5, characterized in that: The gas-water separator also includes a second separation unit, which has the same structure as the first separation unit, wherein the gas-water inlet of the first separation unit is connected to the hydrogen outlet channel of the first connecting piece, the gas-water outlet of the first separation unit is connected to the hydrogen inlet channel of the second connecting piece, the gas-water inlet of the second separation unit is connected to the oxygen outlet channel of the first connecting piece, and the gas outlet of the second separation unit is connected to the oxygen inlet channel of the second connecting piece.

7. The fuel cell stack reaction gas redistribution structure according to claim 5, characterized in that: A centrifugal chamber and a gas chamber are connected in the shell. The gas chamber is located above the centrifugal chamber, the gas-water inlet is connected to the top of the centrifugal chamber, the liquid outlet is connected to the bottom of the centrifugal chamber, and the gas outlet is connected to the top of the gas chamber.

8. The fuel cell stack reaction gas redistribution structure according to claim 7, characterized in that: The centrifugal mechanism includes a motor and a separation paddle connected to each other. The motor is connected to the shell and is located outside the shell. The separation paddle is rotatably arranged in the centrifugal chamber. The motor can drive the separation paddle to rotate to centrifugally separate the gas and water entering the centrifugal chamber from the gas-water inlet.

9. The fuel cell stack reaction gas redistribution structure according to claim 8, characterized in that: The separation paddle comprises a rotating rod and a plurality of water blocking plates, and the plurality of water blocking plates are arranged at intervals along the length direction of the rotating rod.

10. The fuel cell stack reaction gas redistribution structure according to claim 9, characterized in that: The separation paddle further comprises a plurality of liquid anti-rotation plates, which are all located at the bottom of the rotating rod and are evenly arranged around the circumference of the rotating rod.

Images