Electric pile structure with variable-diameter manifolds and fuel cell

Abstract

The utility model relates to an electric pile structure with variable-diameter manifolds and a fuel cell, the electric pile structure with the variable-diameter manifolds comprises an electric pile body, the electric pile body comprises a first end plate, a second end plate and a second reactor core, and the first end plate and the second end plate are respectively arranged at two ends of the second reactor core; the flow guide mechanism comprises a variable-diameter plate, the first end plate is provided with a first flow channel, the second reactor core is provided with a second flow channel communicated with the first flow channel, and the variable-diameter plate is at least arranged in the second flow channel and is arranged on one side close to the input end of the second flow channel. Through the arrangement, the gas transmission speed can be increased, so that gas can reach the interior of the blind-end single battery at the far end more quickly, the gas shortage probability is reduced, and the service life of the galvanic pile is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to fuel cell field especially is a kind of stack structure and fuel cell with variable diameter manifold. BACKGROUND

[0002] Hydrogen energy is a kind of green energy, and has been widely used in recent years in the field of automobile, power station and the like. Proton exchange membrane fuel cell stack is a device for hydrogen and oxygen to occur electrochemical reaction. Multiple single cells are stacked together to form a common passage for hydrogen, oxygen and cooling water to flow through, which is generally referred to as a manifold. Hydrogen, oxygen and cooling water enter the flow channel of bipolar plate through the manifold inlet, and then flow out through the manifold outlet. Different fluids have different cavities and are sealed and separated to avoid leakage or cross leakage between different fluids. The position close to the inlet side of the manifold is the gas inlet end, and the position away from the inlet side of the manifold is the blind end. The manifold is divided into hydrogen gas inlet manifold, hydrogen gas outlet manifold, cooling water inlet manifold, cooling water outlet manifold, air inlet manifold and air outlet manifold. In theory, hydrogen and air will be evenly distributed to the bipolar plate flow channel of each single cell through the gas inlet manifold for normal reaction and power generation. However, since the stack core is composed of multiple single cells connected in series, the distance of each single cell from the manifold inlet position is not equal. A conventional stack structure is shown in Figure 1 The stack core structure is composed of a certain number of single cells. Each single cell is composed of two bipolar plates and one membrane electrode. The number of single cells is increased or decreased according to the size of the stack power.

[0003] During the operation of the conventional stack structure, the following two failure modes are usually prone to occur: ① If the hydrogen or air source is not well separated from water vapor, liquid water will be brought into the stack interior along with the gas, which is easy to concentrate in the flow channel of the single cell close to the gas inlet end. The corresponding single cell will be caused to have performance degradation due to water blocking, and in severe cases, the single cell voltage will be low to cause shutdown and even affect the service life of the stack. ② If the hydrogen or air inlet excess coefficient is insufficient (low gas amount) during the start-up process or operation process of the stack, the gas will be preferentially distributed to the flow channel of the single cell close to the gas inlet end, and the single cell far from the blind end (non-gas inlet end) will have insufficient gas, which will further cause the performance of the under-gas reverse electrode membrane to degrade, and in severe cases, the membrane electrode will be burned through to cause the stack to be unable to operate. This failure mode has more obvious effect on high-power stacks. SUMMARY

[0004] Therefore, the utility model solves the problem of low flow rate at the input end of the stack manifold in the prior art, and provides a stack structure with variable diameter manifold and fuel cell.

[0005] To solve the above technical problems, the utility model provides a kind of electric pile structure with variable diameter manifold, including:

[0006] Electric pile body, it includes: first end plate, second end plate and second core, and the first end plate and second end plate are respectively arranged at the two ends of second core;

[0007] Flow guide mechanism, it includes variable diameter plate, the first end plate is opened with first flow channel, the second core is opened with second flow channel communicated with first flow channel, and the variable diameter plate is at least arranged in second flow channel, and the variable diameter plate is arranged at the side close to the input end of second flow channel.

[0008] In an embodiment of the utility model, the first flow channel includes: oxygen input hole and hydrogen output hole respectively opened in the first side of the first end plate, and hydrogen input hole and oxygen output hole respectively opened in the second side of the first end plate.

[0009] In an embodiment of the utility model, the second flow channel includes: oxygen input flow channel and hydrogen output flow channel respectively arranged in the first side of the second core, and hydrogen input flow channel and oxygen output flow channel respectively opened in the second side of the second core.

[0010] In an embodiment of the utility model, the two ends of hydrogen input flow channel are respectively communicated with hydrogen input hole and hydrogen output flow channel, and the two ends of oxygen input flow channel are respectively communicated with oxygen input hole and oxygen output flow channel;The two ends of hydrogen output flow channel are respectively communicated with hydrogen output hole and hydrogen input flow channel, and the two ends of oxygen output flow channel are respectively communicated with oxygen output hole and oxygen input flow channel.

[0011] In an embodiment of the utility model, the number of variable diameter plate is at least two, and at least one is arranged at the side close to hydrogen input hole of hydrogen input flow channel, and at least another one is arranged at the side close to oxygen input hole of oxygen input flow channel.

[0012] In an embodiment of the utility model, at least two variable diameter plates are respectively arranged along the length direction of oxygen input flow channel and hydrogen input flow channel.

[0013] In an embodiment of the utility model, the variable diameter plate extends to at least part length in first flow channel.

[0014] In an embodiment of the utility model, the variable diameter plate is attached to the inner wall of second flow channel, and the two ends of variable diameter plate are respectively provided with guide portion, and the guide portion is arc or inclined surface.

[0015] In one embodiment of the utility model, the first flow channel further comprises a cooling input hole and a cooling output hole, the second flow channel further comprises a cooling input flow channel and a cooling output flow channel, two ends of the cooling input flow channel are respectively communicated with the cooling input hole and the cooling output flow channel, and an end of the cooling output flow channel is communicated with the cooling output hole.

[0016] The utility model also provides a fuel cell which comprises the electric pile structure with the variable diameter manifold.

[0017] The above technical scheme of the utility model has the following advantages compared with the prior art:

[0018] The electric pile structure with the variable diameter manifold has the following advantages: 1. The variable diameter plate increases the compression speed of the air inlet in the contraction section, disperses the liquid water into water mist at the air inlet end of the air inlet manifold, reduces the water flooding probability, avoids the performance reduction or damage of the membrane electrode, and improves the service life of the electric pile. By changing the structure of the hydrogen inlet manifold and the air inlet manifold, the liquid water carried by the gas source is dispersed into water mist to avoid the water blockage at the head, the gas transmission speed is increased, the gas reaches the blind end single cell at the far end more quickly, the gas shortage probability is reduced, and the service life of the electric pile is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to make the content of the utility model more easily understood, the utility model is further described in detail below according to the specific embodiments of the utility model and in combination with the drawings, wherein

[0020] Figure 1 is a structural schematic view of the prior electric pile;

[0021] Figure 2 is a structural schematic view of the electric pile of the utility model;

[0022] Figure 3 is a front view of the electric pile structure of the utility model;

[0023] Figure 4 is a sectional view of the electric pile structure of the utility model;

[0024] Figure 5 is an enlarged view of A in the utility model. Figure 4

[0025] ​The description reference signs are as follows: 1, upper end plate; 2, upper insulating plate; 3, current collecting plate; 4, first core; 5, current collecting plate; 6, lower insulating plate; 7, lower end plate; 8, reducing plate; 9, guide part; 10, first end plate; 11, second end plate; 16, air input interface; 17, cooling input interface; 18, hydrogen output interface; 19, air output interface; 20, cooling output interface; 21, hydrogen input interface; 22, insulating plate; 23, second core; 24, air inlet manifold; 25, cooling input manifold; 26, hydrogen outlet manifold; 27, air outlet manifold; 28, cooling outlet manifold; 29, hydrogen inlet manifold; 30, hydrogen input flow channel; 31, oxygen input flow channel; 34, hydrogen contraction section; 35, hydrogen expansion section; 36, air contraction section; 37, air expansion section. DETAILED DESCRIPTION

[0026] The utility model will be further explained in combination with the drawings and specific embodiments, so that the person skilled in the art can better understand the utility model and can be implemented, but the embodiment is not as the limitation of the utility model.

[0027] Embodiment 1

[0028] Refer to Figures 2-5 The utility model discloses a kind of electric pile structures with reducing manifold, including:

[0029] Electric pile body, it includes: first end plate 10, second end plate 11 and second core 23, the first end plate 10 and second end plate 11 are respectively arranged in the two ends of second core 23;

[0030] Flow guide mechanism, it includes reducing plate 8, the first end plate 10 is opened with first flow channel, the second core 23 is opened with second flow channel that is communicated with first flow channel, the reducing plate 8 is at least arranged in second flow channel, the reducing plate 8 is arranged in the side close to the input end of second flow channel.

[0031] The utility model discloses a kind of electric pile structures with variable diameter manifold, when electric pile works, different fluid is entered into electric pile by being opened first flow passage on first end plate 10, by first flow passage into second core 23 second flow passage, since variable diameter plate 8 is arranged in second flow passage side close to input end, when hydrogen enters second flow passage and passes through variable diameter plate 8, the place of second flow passage makes hydrogen in flow passage The flow cross section of section is reduced, the fluid velocity of this place is increased.Furthermore, hydrogen and oxygen enter the inside of second core 23 with high speed, can be more quickly and evenly distributed to each single cell, not only by accelerating the gas inlet end hydrogen gas inlet manifold 29 and oxygen gas inlet manifold flow rate will be carried by gas source Liquid water is dispersed into water mist to avoid head water blockage, also by accelerating gas transmission speed makes gas more quickly reaches the blind end single cell inside of far end reduces the probability of under gas, to enhance the service life of electric pile.

[0032] The first flow passage includes: oxygen input hole and hydrogen output hole opened on the first side of the first end plate 10 respectively, and hydrogen input hole and oxygen output hole opened on the second side of the first end plate 10 respectively, oxygen enters the electric pile through the oxygen input hole on the first side of the first end plate 10. Hydrogen enters the electric pile from the hydrogen input hole on the second side of the first end plate 10. After hydrogen enters the hydrogen input hole, it flows along the corresponding first flow passage branch, flows into the hydrogen input flow passage 30 of the second core 23, and reaches each single cell to participate in electrochemical reaction.

[0033] The second flow passage includes: oxygen input flow passage 31 and hydrogen output flow passage arranged on the first side of the second core 23 respectively, and hydrogen input flow passage 30 and oxygen output flow passage opened on the second side of the second core 23 respectively. Oxygen entering from the oxygen input hole of the first end plate 10 enters the oxygen input flow passage 31. In the oxygen input flow passage 31, it is evenly distributed to each single cell to participate in electrochemical reaction. At the same time, hydrogen entering from the hydrogen input hole of the first end plate 10 flows into the hydrogen input flow passage 30 on the second side of the second core 23. Under the guidance of the hydrogen input flow passage 30, hydrogen uniformly reaches each single cell and participates in electrochemical reaction with oxygen.

[0034] Hydrogen first enters the hydrogen input hole through the hydrogen gas inlet joint, and then is gradually distributed from the gas inlet end to the blind end. Hydrogen enters the bipolar plate flow passage in sequence to participate in the reaction at the hydrogen inlet manifold. In the variable diameter contraction section, the gas is compressed at an increased speed, which can disperse the liquid water entering the section into water mist to avoid water blockage at the gas inlet end, and can make the hydrogen and air entering the stack faster through acceleration to avoid under-gas, thereby enhancing the service life of the electric pile. Figure 2For reference, the first side of the first end plate 10 and the first side of the second core 23 are the left sides of the respective bodies, and the second sides of the first end plate 10 and the second core 23 are the right sides of the respective bodies. The stacking direction of the single cells is the front-rear direction. The second core 23 is formed by stacking a plurality of single cells, and each single cell is provided with a corresponding hole to form a second flow channel, and the oxygen or hydrogen in the second flow channel passes through the gap between the single cells to the adjacent single cells. The oxygen input hole and the hydrogen output hole are arranged along the same vertical plane, and the oxygen output hole and the hydrogen input hole are arranged along the same vertical plane; the oxygen input flow channel 31 and the hydrogen output flow channel are arranged along the same vertical plane, and the oxygen output flow channel and the hydrogen input flow channel 30 are arranged along the same vertical plane. And the hydrogen flow channel and the oxygen flow channel are staggered, that is, the center lines of the oxygen input hole and the oxygen input flow channel 31 and the hydrogen input hole and the hydrogen input flow channel are located on the same horizontal plane, so that the hydrogen and oxygen enter from the symmetrical positions on the left and right sides of the single cell; the center lines of the oxygen output hole and the oxygen output flow channel and the hydrogen output hole and the hydrogen output flow channel are located on the same horizontal plane.

[0035] The two ends of the hydrogen input flow channel 30 are respectively communicated with the hydrogen input hole and the hydrogen output flow channel, and the two ends of the oxygen input flow channel 31 are respectively communicated with the oxygen input hole and the oxygen output flow channel; the two ends of the hydrogen output flow channel are respectively communicated with the hydrogen output hole and the hydrogen input flow channel 30, and the two ends of the oxygen output flow channel are respectively communicated with the oxygen output hole and the oxygen input flow channel 31. The hydrogen enters the hydrogen input hole of the first end plate 10, and due to the communication relationship between the hydrogen input flow channel 30 and the hydrogen input hole, the hydrogen directly flows into the hydrogen input flow channel 30. The oxygen enters the oxygen input hole of the first end plate 10, and through the communication between the oxygen input flow channel 31 and the oxygen input hole, the oxygen flows into the oxygen input flow channel 31. The oxygen enters each single cell under the guidance of the oxygen input flow channel 31 to provide oxygen for the electrochemical reaction.

[0036] The oxygen input hole, the hydrogen input hole, the hydrogen input flow channel 30, the oxygen input flow channel 31, the oxygen output flow channel, the hydrogen output flow channel, the oxygen output hole, and the hydrogen output hole form a manifold structure communicated with each other.

[0037] The number of the variable-diameter plates 8 is at least two, and at least one is arranged on the side of the hydrogen input flow channel 30 close to the hydrogen input hole, and at least another one is arranged on the side of the oxygen input flow channel 31 close to the oxygen input hole. Hydrogen enters the hydrogen input flow channel 30 from the hydrogen input hole, meets the variable-diameter plate 8 arranged on the side close to the hydrogen input hole, and the cross-sectional area of the flow channel at the variable-diameter plate 8 becomes smaller. In the case of constant flow, the flow rate of hydrogen at the front end of the second flow channel will increase significantly. This enables hydrogen to enter the inside of the stack more quickly and be more evenly distributed to each single cell in the subsequent flow channel. Similarly, oxygen enters the hydrogen input flow channel 30 from the oxygen input hole, meets the variable-diameter plate 8 arranged on the side close to the hydrogen input hole, and the cross-sectional area of the flow channel at the variable-diameter plate 8 becomes smaller. In the case of constant flow, the flow rate of hydrogen at the front end of the second flow channel will increase significantly. A converging variable-diameter structure is arranged at the gas inlet end of the oxygen input flow channel 31 and the hydrogen input flow channel 30. The variable-diameter structure is realized by integrating the variable-diameter plate 8 on the insulating plate 22 of the stack, and the contraction cross section and the contraction length can be freely adjusted according to the structure of the stack gas inlet manifold and the length of the second stack core 23. In this embodiment, the contraction section area is 5 / 6 of the expansion section area, and the contraction length is 1 / 3 of the total length of the hydrogen input flow channel 30 and the oxygen input flow channel 31.

[0038] The hydrogen input flow channel 30 includes a hydrogen contraction section 34 and a hydrogen expansion section 35, and the air input flow channel includes an air contraction section 36 and an air expansion section 37. In the expansion section, the pressure can be reduced to improve the atomization effect and avoid water blockage.

[0039] At least two variable-diameter plates 8 are arranged along the length direction of the oxygen input flow channel 31 and the hydrogen input flow channel 30, respectively. In some embodiments, the thickness of the variable-diameter plate 8 body gradually increases in the extension direction away from the input end of the second flow channel, to adapt to different structures of the stack. The thickness of the variable-diameter plate 8 starts from zero at the inlet of the first flow channel, and the surface extends obliquely until the end of the oxygen input flow channel 31 and the hydrogen input flow channel 30 to reach the maximum.

[0040] The variable-diameter plate 8 extends to at least part of the length of the first flow channel, for example, the variable-diameter plate 8 extends to half the length of the first flow channel. The oxygen input hole, the hydrogen input hole, the oxygen output hole, and the hydrogen output hole constitute the first flow channel. The variable-diameter plate 8 extends to the first flow channel, so that the first flow channel forms an outwardly expanding horn mouth, which is convenient for connecting to the outside and can accelerate the intake of gas and oxygen outside the second flow channel.

[0041] The variable-diameter plate 8 is attached to the inner wall of the second flow channel, and the two ends of the variable-diameter plate 8 are respectively provided with guide portions 9 which are arc-shaped or inclined, so that the flow direction of hydrogen and oxygen gradually changes, avoiding direct impact of the gas on the variable-diameter plate 8, thereby enabling the gas to enter the variable-diameter plate 8 more smoothly and increase the flow rate in the area.

[0042] The first flow channel further comprises a cooling input hole and a cooling output hole, and the second flow channel further comprises a cooling input flow channel and a cooling output flow channel, two ends of the cooling input flow channel being communicated with the cooling input hole and the cooling output flow channel respectively, and an end of the cooling output flow channel being communicated with the cooling output hole. An external cooling system pumps cooling medium into the cooling input hole of the first end plate 10, and the cooling medium flows into the cooling input flow channel through the cooling input hole. In the cooling input flow channel, the cooling medium absorbs heat from the second core 23. The cooling medium flows from the cooling input flow channel to the cooling output flow channel, and then flows to the cooling output hole of the first end plate 10 through the cooling output flow channel, and is discharged from the stack to the external cooling system. After being cooled by the external cooling system, the cooling medium enters the stack again through the cooling input hole to start a new cycle.

[0043] In this embodiment, the oxygen source is provided by the oxygen component in air, and the cooling medium is water. Specifically, the first end plate 10 is provided with two corresponding insulation plates 22 and mounting plates, the insulation plates 22 are provided with a plurality of holes, and the two mounting plates are respectively provided with interfaces corresponding to the holes of the insulation plates 22 and the first end plate 10 to form a manifold structure of the first flow channel and the second flow channel. That is, air inlet manifold 24, cooling input manifold 25, hydrogen outlet manifold 26, air outlet manifold 27, cooling outlet manifold 28, and hydrogen inlet manifold 29.

[0044] The one mounting plate is configured with an air input interface 16, a cooling input interface 17, and a hydrogen output interface 18; and the other mounting plate is configured with a hydrogen input interface 21, a cooling output interface 20, and an air output interface 19. Each interface on the two mounting plates forms a first flow channel with the corresponding holes of the insulation plate 22 and the first end plate 10.

[0045] Embodiment 2

[0046] The embodiment provides a fuel cell, which comprises the stack structure with the variable-diameter manifold as described in embodiment 1.

[0047] The fuel cell provided by the embodiment further comprises a fuel supply subsystem, an oxidant supply subsystem, a water thermal management subsystem, and an electrical management and control subsystem, etc. connected with the stack structure. The variable-diameter inlet manifold structure is suitable for all closed inlet structures of the stack, including but not limited to water-cooled metal bipolar plate stacks, graphite bipolar plate stacks, composite bipolar plate stacks, and various forms of air-cooled stacks; the contraction section cross-sectional ratio and length ratio of the variable-diameter inlet manifold can be adjusted according to the specific structure of the stack to achieve the best inlet distribution effect.

[0048] In some embodiments, the variable-diameter plate can be integrally processed with the insulating plate to form a variable-diameter intake manifold after the stack is assembled; the variable-diameter structure can be separately processed to form a variable-diameter plate, which is then installed at a corresponding position of the insulating plate through assembly to form a variable-diameter intake manifold after the stack is assembled; or the variable-diameter structure can be formed into a variable-diameter intake manifold through gluing after the stack is assembled.

[0049] Obviously, the above embodiments are only examples for clearly illustrating the present application, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A stack structure having a variable diameter manifold, characterized by, The application relates to an electric pile structure with a variable-diameter manifold. The electric pile structure comprises a pile body, a flow guide mechanism and a cooling mechanism. The pile body comprises a first end plate, a second end plate and a second pile core.

2. The stack structure with a variable diameter manifold according to claim 1, characterized in that: The flow guide mechanism comprises a variable-diameter plate.

3. The stack structure with a variable diameter manifold according to claim 2, characterized in that: The first end plate is provided with a first flow channel.

4. The stack structure with a variable diameter manifold according to claim 3, characterized in that: The second pile core is provided with a second flow channel connected with the first flow channel.

5. The stack structure with a variable diameter manifold according to claim 3, characterized in that: The variable-diameter plate is arranged on one side close to the input end of the second flow channel.

6. The stack structure with a variable diameter manifold according to claim 3, characterized in that: The first flow channel comprises oxygen input holes and hydrogen output holes arranged on the first side of the first end plate, and hydrogen input holes and oxygen output holes arranged on the second side of the first end plate.

7. The stack structure with a variable diameter manifold according to claim 1, characterized in that: The second flow channel comprises oxygen input flow channels and hydrogen output flow channels arranged on the first side of the second pile core, and hydrogen input flow channels and oxygen output flow channels arranged on the second side of the second pile core.

8. The stack structure with a variable diameter manifold according to claim 1, characterized in that: The two ends of the hydrogen input flow channel are connected with the hydrogen input holes and the hydrogen output flow channel.

9. The stack structure with a variable diameter manifold according to claim 1, characterized in that: The two ends of the oxygen input flow channel are connected with the oxygen input holes and the oxygen output flow channel.

10. A fuel cell characterized by comprising: The two ends of the hydrogen output flow channel are connected with the hydrogen output holes and the hydrogen input flow channel. The two ends of the oxygen output flow channel are connected with the oxygen output holes and the oxygen input flow channel. The variable-diameter plate comprises at least two variable-diameter plates. At least one variable-diameter plate is arranged on one side close to the hydrogen input holes of the hydrogen input flow channel. At least one variable-diameter plate is arranged on one side close to the oxygen input holes of the oxygen input flow channel. The variable-diameter plates are arranged along the length direction of the oxygen input flow channel and the hydrogen input flow channel. The variable-diameter plate extends to at least part of the length of the first flow channel. The variable-diameter plate is attached to the inner wall of the second flow channel. The two ends of the variable-diameter plate are provided with guide portions. The guide portions are arc-shaped or inclined. The first flow channel further comprises cooling input holes and cooling output holes. The second flow channel further comprises cooling input flow channels and cooling output flow channels. The two ends of the cooling input flow channel are connected with the cooling input holes and the cooling output flow channel. The end of the cooling output flow channel is connected with the cooling output holes. The application further discloses an electric pile structure with a variable-diameter manifold.

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