Single-plate double-flow-field polar plate structure for high-power hydrogen fuel cell

Abstract

The utility model discloses a single-plate double-flow-field polar plate structure for a high-power hydrogen fuel cell. A double-flow field structure is arranged in the middle of the polar plate, and the double-flow field is composed of a polar plate lower side reaction area and a polar plate upper side reaction area; the polar plate lower side reaction region is isolated from the polar plate upper side reaction region; an air outlet cavity opening and an air inlet cavity opening are formed in the two sides of the double-flow-field structure correspondingly. A cooling liquid outlet and a cooling liquid inlet are formed in the two sides of the double-flow-field structure correspondingly. A hydrogen inlet cavity opening and a hydrogen outlet cavity opening are further formed in one side of the double-flow-field structure provided with the cooling liquid outlet; and a hydrogen transfer cavity opening is formed in the cooling liquid inlet. The problem of flow distribution uniformity of an existing single-plate single flow field is solved by adopting a single-plate double-flow field mode; the problem that the local temperature of the center position of an existing single-plate single-flow field and the temperature gradient of the periphery are large is solved in a single-plate double-flow field mode. The sealant groove in the middle of the pole plate can effectively improve the overall bending strength of the pole plate.

Description

Technical Field

[0001] The utility model belongs to the field of fuel cells and relates to a polar plate structure, in particular to a single-plate double-flow field polar plate structure for high-power hydrogen fuel cells. Background Art

[0002] Proton exchange membrane fuel cells have the advantages of high energy conversion rate, low noise, and zero emissions. Among them, hydrogen fuel cell products, which are mainly used in vehicles on the mobile end, have great advantages and potential in the field of medium- and long-distance and heavy-duty transportation as the application scenarios expand. They are an important direction for the development of high-performance, low-pollution commercial vehicles. As the power demand for medium- and long-distance and heavy-duty commercial vehicles increases, the power of fuel cell systems is also increasing. Therefore, the power demand for the plates of high-power hydrogen fuel cell stacks is also increasing.

[0003] The existing hydrogen fuel cell stack plates are all in the form of one plate with one flow field, and there is no structure with two flow fields on one plate. The larger the reaction area of ​​a single plate with a single flow field, the worse the uniformity of flow distribution will be, and the performance will be reduced; the larger the reaction area of ​​a single plate with a single flow field, the greater the temperature gradient difference between the center and the periphery of the reaction area, and there is also the problem of reduced bending strength of the plate. Utility Model Content

[0004] The utility model overcomes the above defects and provides a single-plate dual-flow field plate structure for high-power hydrogen fuel cells. The utility model adopts a single-plate dual-flow field method to improve the current flow distribution uniformity problem of a single-plate single-flow field; the single-plate dual-flow field method improves the current problem of a large local temperature gradient between the center position and the surrounding temperature of a single-plate single-flow field; a sealant groove in the middle of the plate can effectively improve the overall bending strength of the plate.

[0005] The technical solution of the utility model is as follows.

[0006] A single-plate dual-flow field plate structure for a high-power hydrogen fuel cell, wherein a dual-flow field structure is arranged in the middle of the plate, and the dual-flow field is composed of a reaction zone on the lower side of the plate and a reaction zone on the upper side of the plate;

[0007] The reaction zone on the lower side of the electrode plate is isolated from the reaction zone on the upper side of the electrode plate; the two sides of the double flow field structure are respectively provided with air outlet cavities and air inlet cavities; the two sides of the double flow field structure are also respectively provided with a coolant outlet and a coolant inlet; the double flow field structure provided with a coolant outlet is also provided with a hydrogen inlet cavity and a hydrogen outlet cavity on one side;

[0008] A hydrogen transfer cavity is arranged in the coolant inlet.

[0009] Furthermore, the hydrogen transfer cavity is located on one side of the junction between the reaction zone on the lower side of the plate and the reaction zone on the upper side of the plate, and is used as a gathering point for hydrogen that has not been fully reacted in the reaction zone on the upper side of the plate from the inlet cavity, and at the same time serves as a hydrogen inlet for the reaction zone on the lower side of the plate. The coolant inlet surrounds the hydrogen transfer cavity, and can always keep the hydrogen temperature in the hydrogen transfer cavity within the appropriate operating temperature range of the fuel cell, wherein the hydrogen transfer cavity has a lowest point design to facilitate the collection and discharge of liquid water in the reaction zone on the upper side of the plate.

[0010] Further, the coolant outlet includes a first coolant outlet and a second coolant outlet.

[0011] Furthermore, the air inlet openings are all independent openings, and the air inlet openings are isolated by sealing rings.

[0012] Furthermore, the reaction zone on the lower side of the electrode plate and the reaction zone on the upper side of the electrode plate are two independent electrochemical reaction areas, which are isolated by a sealing ring.

[0013] Furthermore, the sealing ring is arranged on the electrode plate by dispensing or pasting.

[0014] The utility model discloses a single-plate dual-flow field plate structure for a high-power hydrogen fuel cell, wherein a dual-flow field structure is arranged in the middle of the plate, and the dual-flow field is composed of a reaction zone on the lower side of the plate and a reaction zone on the upper side of the plate;

[0015] The reaction area on the lower side of the electrode plate and the reaction area on the upper side of the electrode plate are two independent electrochemical reaction areas, which are isolated by a sealing ring;

[0016] A hydrogen inlet cavity, a first coolant outlet, a first air outlet cavity, a first air inlet cavity, a second coolant outlet, and a hydrogen outlet cavity are respectively arranged on one side of the double flow field structure; a second air outlet cavity, a coolant inlet, and a second air inlet cavity are respectively arranged on the other side of the double flow field structure;

[0017] A hydrogen transfer cavity is arranged in the coolant inlet.

[0018] The method for using the single-plate double-flow field electrode structure of the utility model comprises the following steps:

[0019] (1) The hydrogen working route on the anode side of the electrode plate is from the hydrogen inlet cavity through the upper reaction zone of the electrode plate to the hydrogen transfer cavity and then through the lower reaction zone of the electrode plate to the hydrogen outlet cavity to complete the electrochemical reaction of hydrogen in the two reaction zones;

[0020] (2) The air working routes on the cathode side of the electrode plate are two separate routes. The first route is from the second air inlet cavity through the upper reaction zone of the electrode plate to provide the air required for the electrochemical reaction and then reach the first air outlet cavity; the second route is from the first air inlet cavity through the lower reaction zone of the electrode plate to provide the air required for the electrochemical reaction and then reach the second air outlet cavity;

[0021] (3) The working route of the coolant in the electrode plate cooling circuit is to flow out from the coolant inlet in two ways. The first way passes through the upper reaction zone of the electrode plate to reach the first coolant outlet to complete the temperature control of the upper reaction zone of the electrode plate; the second way passes through the lower reaction zone of the electrode plate to reach the second coolant outlet to complete the temperature control of the lower reaction zone of the electrode plate.

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] (1) In the prior art, the larger the flow field area of ​​a single electrode plate, the more likely it is that the flow distribution will be uneven. The present invention can greatly improve the uniformity of the overall flow distribution by arranging two independent flow fields on the same electrode plate.

[0024] (2) The larger the flow field area of ​​a single electrode plate, the greater the flow resistance generated on the cathode side, and the more likely it is that water flooding and water blockage will occur. The solution described in the utility model can greatly improve the problem of water flooding and water blockage by arranging two independent flow fields on the same electrode plate, thereby making the performance consistency of the battery stack higher.

[0025] (3) The larger the flow field area of ​​a single electrode plate, the lower the strength and rigidity of the electrode plate will be due to the weight of the electrode plate after the material is removed. The solution described in the utility model arranges two independent flow fields on the same electrode plate and adds a sealing groove design (the sealing groove is used to place a sealing ring) between the two independent flow fields, which can effectively improve the strength and rigidity of the electrode plate and reduce the breakage rate of the electrode plate.

[0026] (4) The larger the flow field area of ​​a single electrode plate, the worse the temperature heat dissipation capacity of the center area of ​​the electrode plate will be, and the overall temperature control capability of the fuel cell stack will be required to be higher. The solution described in the utility model arranges two independent flow fields on the same electrode plate to make the overall temperature concentration point of the electrode plate more dispersed, which is more conducive to the heat dissipation of the fuel cell stack at high temperature, reduces the parasitic power consumption of the thermal management subsystem of the hydrogen fuel cell system, reduces the power consumption demand of the radiator, reduces the overall cost of the hydrogen fuel system, and improves the efficiency of the fuel cell system.

[0027] (5) The utility model has only one anode hydrogen inlet and one anode hydrogen outlet on the entire electrode plate. The water generated by the anode hydrogen in the upper reaction zone of the electrode plate moistens the hydrogen and then enters the lower reaction zone of the electrode plate through the hydrogen transfer cavity. This can eliminate half of the humidification effect requirements of the humidifier. Only the cathode air in the upper reaction zone of the electrode plate needs to be humidified, while the cathode air in the lower reaction zone of the electrode plate does not need to be humidified. Therefore, when the same power stack is integrated into the system, only humidifier components with half the cathode flow capacity are needed, which reduces the cost, volume and weight of the system integration, thereby improving the system power density ratio and reducing the system integration cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the structure of a single-plate double-flow field electrode plate for a high-power hydrogen fuel cell according to the utility model;

[0029] Figure 2 This is the hydrogen working route diagram of the anode side of the pole plate of the utility model;

[0030] Figure 3 This is the air working route diagram of the cathode side of the pole plate of the utility model.

[0031] The components in the figure are as follows:

[0032] Hydrogen inlet cavity 1, first coolant outlet 2, first air outlet cavity 3, first air inlet cavity 4, second coolant outlet 5, hydrogen outlet cavity 6, reaction zone 7 on the lower side of the electrode plate, second air outlet cavity 8, coolant inlet 9, hydrogen transfer cavity 10, sealing ring 11, second air inlet cavity 12, reaction zone 13 on the upper side of the electrode plate. DETAILED DESCRIPTION

[0033] The following description combines specific illustrations to explain the technical solution in order to fully understand the utility model application. However, the present application can be implemented in many other ways different from those described herein, and similar generalization embodiments made by ordinary technicians in the field without creative work are all within the scope of protection of the utility model.

[0034] Example 1

[0035] like Figure 1 As shown, the hydrogen fuel cell stack plate involved in the utility model is mainly composed of the following parts:

[0036] A double flow field structure is arranged in the middle of the electrode plate, and the double flow field is composed of a reaction zone 7 on the lower side of the electrode plate and a reaction zone 13 on the upper side of the electrode plate;

[0037] The reaction area 7 on the lower side of the electrode plate and the reaction area 13 on the upper side of the electrode plate are two independent electrochemical reaction areas, which are isolated by a sealing ring 11;

[0038] One side of the double flow field structure is provided with a hydrogen inlet cavity 1, a coolant outlet 2, an air outlet cavity 3, an air inlet cavity 4, a coolant outlet 5, and a hydrogen outlet cavity 6 from top to bottom, and the above arrangements are arranged in sequence; the other side of the double flow field structure is provided with an air outlet cavity 8, a coolant inlet 9 and an air inlet cavity 12 from bottom to top; a hydrogen transfer cavity 10 is provided in the coolant inlet 9.

[0039] In this embodiment, the hydrogen transfer cavity 10 is located on one side of the junction between the reaction zone 7 on the lower side of the electrode plate and the reaction zone 13 on the upper side of the electrode plate.

[0040] In this embodiment, the air inlet openings are all independent openings, and the air inlet openings are isolated by sealing rings 11 .

[0041] In this embodiment, the reaction area 7 on the lower side of the electrode plate and the reaction area 13 on the upper side of the electrode plate are two independent electrochemical reaction areas, which are isolated by a sealing ring 11 .

[0042] In this embodiment, the sealing ring 11 is arranged on the electrode plate by dispensing or pasting.

[0043] In this embodiment, under the same reaction zone area, the temperature distribution uniformity of the single plate double flow field is better, and the temperature difference range between the highest point and the lowest point is smaller; under the same reaction zone area, the bending strength of the electrode plate of the single plate double flow field is relatively improved.

[0044] Example 2

[0045] The use method of the single-plate double-flow field electrode structure of the utility model:

[0046] (1) The hydrogen working route on the anode side of the electrode plate is from the hydrogen inlet cavity 1 through the upper reaction zone 13 of the electrode plate to the hydrogen transfer cavity 10 and then through the lower reaction zone 7 of the electrode plate to the hydrogen outlet cavity 6 to complete the electrochemical reaction of hydrogen in the two reaction zones;

[0047] (2) There are two separate air working routes on the cathode side of the plate. The first route is from the second air inlet cavity 12 through the upper reaction zone 13 of the plate to provide the air required for the electrochemical reaction and then reach the first air outlet cavity 3; the second route is from the first air inlet cavity 4 through the lower reaction zone 7 of the plate to provide the air required for the electrochemical reaction and then reach the second air outlet cavity 8;

[0048] (3) The working route of the coolant in the electrode plate cooling circuit is to flow out from the coolant inlet 9 in two ways. The first way passes through the upper reaction zone 13 of the electrode plate to reach the first coolant outlet 2 to complete the temperature control of the upper reaction zone 13 of the electrode plate; the second way passes through the lower reaction zone 7 of the electrode plate to reach the second coolant outlet 5 to complete the temperature control of the lower reaction zone 7 of the electrode plate.

Claims

1. A single-plate dual-flow field plate structure for a high-power hydrogen fuel cell, characterized in that: A double flow field structure is arranged in the middle of the electrode plate, and the double flow field is composed of a reaction zone (7) on the lower side of the electrode plate and a reaction zone (13) on the upper side of the electrode plate; The reaction zone (7) on the lower side of the electrode plate is isolated from the reaction zone (13) on the upper side of the electrode plate; air outlet cavities and air inlet cavities are respectively provided on both sides of the double flow field structure; a coolant outlet and a coolant inlet (9) are also respectively provided on both sides of the double flow field structure; a hydrogen inlet cavities (1) and a hydrogen outlet cavities (6) are also provided on one side of the double flow field structure provided with the coolant outlet; A hydrogen transfer cavity (10) is provided in the cooling liquid inlet (9); The hydrogen transfer cavity opening (10) is located on one side of the junction between the reaction zone (7) on the lower side of the electrode plate and the reaction zone (13) on the upper side of the electrode plate; The coolant outlet comprises a first coolant outlet (2) and a second coolant outlet (5); The air inlet cavities are all independent cavities, and the air inlet cavities are isolated by sealing rings (11); The reaction area (7) on the lower side of the electrode plate and the reaction area (13) on the upper side of the electrode plate are two independent electrochemical reaction areas, which are isolated by a sealing ring (11); The sealing ring (11) is arranged on the electrode plate by dispensing; A hydrogen inlet cavity (1), a first coolant outlet (2), a first air outlet cavity (3), a first air inlet cavity (4), a second coolant outlet (5), and a hydrogen outlet cavity (6) are respectively arranged on one side of the dual flow field structure; a second air outlet cavity (8), a coolant inlet (9), and a second air inlet cavity (12) are respectively arranged on the other side of the dual flow field structure.

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