Cathode open type air-cooled fuel cell bipolar plate

Abstract

The invention belongs to the technical field of fuel cell bipolar plates, and particularly relates to a cathode open type air-cooled fuel cell bipolar plate, which comprises a bipolar plate body, and the two surfaces of the bipolar plate body are respectively configured as an anode side and a cathode side; the anode side is provided with a plurality of parallel anode runners, the anode runners are arranged along the length direction of the bipolar plate body, and the anode runners are straight runners or wave runners; a plurality of sections of flow fields are arranged on the cathode side, the plurality of sections of flow fields are arranged along the width direction of the bipolar plate body, each section of flow field comprises a plurality of parallel cathode flow channels, and in two adjacent sections of flow fields, the cathode flow channels are arranged in a staggered manner; a plurality of parallel cooling flow channels are formed in the bipolar plate body along the width direction, and the cooling flow channels are positioned between the anode side and the cathode side. Under the condition that the length and width of the bipolar plate are not increased, the mass transfer uniformity and the temperature distribution uniformity are improved, and the electrochemical reaction efficiency and the overall performance of a fuel cell stack are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of fuel cell bipolar plates, and in particular relates to a cathode open air-cooled fuel cell bipolar plate. Background Art

[0002] A fuel cell stack consists of multiple key components, including end plates, insulating plates, current collecting plates, bipolar plates, seals, membrane electrode assemblies, and fasteners. The bipolar plates are crucial to the performance of the stack, not only considering the mass transfer characteristics and electrical conductivity of the electrochemical reaction, but also the heat exchange efficiency in the cooling system to ensure that the entire stack can operate in the best condition.

[0003] The bipolar plate flow field design of the fuel cell stack is the main factor affecting its internal gas transmission, water transport and temperature distribution. By optimizing the flow field design, the reactants can be effectively distributed, high gas utilization and easy water removal can be achieved, which is crucial to improving the performance of the fuel cell. There are two cooling methods for fuel cells: air cooling and liquid cooling. Air-cooled fuel cells are different from water-cooled fuel cells. The heat generated by the bipolar plates is mainly carried away by external air flow. Since air has a small specific heat capacity and can only carry a limited amount of heat, the temperature control level and temperature distribution uniformity have become the main factors restricting the performance of air-cooled fuel cells.

[0004] According to the different cathode cooling methods, air-cooled fuel cells are divided into cathode closed air-cooled fuel cells and cathode open air-cooled fuel cells. The cooling air and the air participating in the chemical reaction of the cathode closed air-cooled fuel cell are supplied separately, and each has an independent channel. This design increases the complexity of the system. Compared with the cathode closed air-cooled fuel cell, the bipolar plate structure of the cathode open air-cooled fuel cell is simpler, with fewer auxiliary systems and lower additional power consumption, which is more convenient for portable scene applications. However, the air used for cooling the cathode open air-cooled fuel cell and the air participating in the reaction are both supplied to the cathode flow channel through a fan. The air dissipates heat and cools the bipolar plate while participating in the reaction, which makes the reaction and heat dissipation affect each other in the limited cathode flow channel space, and the insufficient heat dissipation capacity causes the temperature of the cathode flow channel to gradually increase along the way, which is not conducive to the uniformity of the power density of the stack. In order to achieve sufficient excess air, the fan speed must be increased, which increases the additional energy consumption and noise.

[0005] Patent CN113451601A provides a cathode open air-cooled fuel cell bipolar plate with double-sided flow channels. The bipolar plate is designed with serpentine hydrogen flow channels and arc-shaped air flow channels. The hydrogen flow channels are four parallel serpentine flow channels, which are bent multiple times from the hydrogen inlet to the hydrogen outlet; the curvature of the air flow channel is 5°. The patent believes that the arc flow channel can interfere with the air flow, increase the concentration of air entering the cathode gas diffusion layer, and improve the performance of the air-cooled fuel cell. However, this bipolar plate design has a small hydrogen inlet and outlet, a small number of anode serpentine flow channels, too many bends and too long paths, huge flow resistance in the anode flow field, and a large inlet and outlet pressure drop, which causes the hydrogen concentration in the anode flow channel to decrease, resulting in uneven power density in the length direction; at the same time, the concave flow field of the cathode flow channel will also increase the flow resistance, resulting in insufficient mass transfer capacity, slow gas transfer rate and uneven distribution.

[0006] Patent CN220358139U discloses an air-cooled fuel cell stack, whose cooling flow field is arranged on both sides of the anode flow field, and is mutually offset with the anode flow field and the cathode flow field, so as to ensure that the air-cooled fuel cell stack has a smaller size in its stacking direction, that is, the overall thickness is thinner, and it can be applied to certain application scenarios with strict requirements on thickness size. However, in order to pursue a smaller size in the thickness direction of the plate, this cathode open air-cooled stack arranges the cooling flow field on both sides of the anode flow field, which undoubtedly greatly increases the size in the width direction of the plate, and makes it impossible for the cooling flow field to directly cool the center part of the battery where the heat is most serious through air convection heat exchange, and the heat removed only by heat conduction on both sides is extremely limited.

[0007] Analysis shows that for cathode open air-cooled fuel cells, how to improve the mass transfer and heat transfer characteristics without increasing the length and width of the bipolar plate is a technical problem that needs to be solved. Summary of the invention

[0008] In order to solve the above technical problems, the present invention provides a cathode open air-cooled fuel cell bipolar plate. Compared with the traditional cathode open air-cooled fuel cell bipolar plate, the present invention improves the mass transfer uniformity and temperature distribution uniformity without increasing the length and width of the bipolar plate.

[0009] The present invention is specifically implemented through the following scheme.

[0010] The present invention provides a cathode open air-cooled fuel cell bipolar plate, comprising a bipolar plate body, wherein two side surfaces of the bipolar plate body are respectively configured as an anode side and a cathode side.

[0011] The anode side is provided with a plurality of parallel anode flow channels, which are arranged along the length direction of the bipolar plate body, and are straight flow channels or wavy flow channels, and hydrogen flows from one end of the anode flow channel to the other end of the anode flow channel.

[0012] The cathode side is provided with multiple flow fields, which are arranged along the width direction of the bipolar plate body, and a transition zone is configured between two adjacent flow fields. Each flow field includes multiple parallel cathode flow channels, and the cathode flow channels are arranged along the width direction of the bipolar plate body. In two adjacent flow fields, the cathode flow channels are arranged in an alternating manner.

[0013] A plurality of parallel cooling channels are opened on the bipolar plate body between the anode side and the cathode side. The cooling channels are arranged along the width direction of the bipolar plate body, and both ends of the cooling channels respectively penetrate the bipolar plate body; the cooling channels and the cathode channels take in air on the same side and discharge air on the same side, sharing a common air source.

[0014] The present invention provides a cathode open air-cooled fuel cell bipolar plate that enhances heat dissipation and uniformity of flow field distribution. Compared with the traditional open air-cooled fuel cell bipolar plate, the anode flow channel adopts parallel flow channels, which reduces the anode inlet and outlet pressure drop while ensuring the anode flow field mass transfer efficiency; the cathode flow field adopts a segmented cross-row disturbance flow design, which strengthens the cathode gas disturbance flow, enhances the cathode flow field mass transfer efficiency, and greatly improves the mass transfer uniformity and temperature distribution uniformity, thereby improving the electrochemical reaction efficiency and the overall performance of the fuel cell stack. The amount of air entering the cathode flow channel ensures the amount required for the cathode reaction while playing a partial cooling role. The main cooling function is completed by the cooling flow channel, which significantly improves the temperature control level. The present invention can increase the convection heat exchange area of ​​the bipolar plate without increasing the length and width of the bipolar plate, and achieves a significant temperature control purpose under the condition of unchanged fan power consumption, and can control the temperature of the fuel cell stack in the most ideal temperature range.

[0015] In a preferred embodiment of the present invention, an anode channel ridge is arranged between two adjacent anode channels, the width of the anode channel is 0.5 mm to 2 mm, the width of the anode channel ridge is 0.5 mm to 2 mm, and the depth of the anode channel is 0.2 mm to 0.5 mm.

[0016] In a preferred embodiment of the present invention, a plurality of parallel anode flow channels constitute an anode flow field, anode through holes are respectively opened at both ends of the bipolar plate body, and anode gas distribution areas are respectively arranged around the two anode through holes on the anode side, and the anode gas distribution areas connect the anode through holes and the anode flow field; the width of the anode gas distribution area is the same as the width of the anode flow field, and the width of the anode through hole is 2 mm to 4 mm smaller than the width of the anode gas distribution area. The large-diameter anode through hole and anode gas distribution area design can ensure uniform gas distribution in the anode flow channel.

[0017] In a preferred embodiment of the present invention, the cathode flow channel is a straight flow channel or a wavy flow channel, and a cathode flow channel ridge is configured between two adjacent cathode flow channels. The width of the cathode flow channel is 0.75mm~3mm, the width of the cathode flow channel ridge is 0.5mm~2mm, and the cathode flow channel width is greater than the cathode flow channel ridge width, and the depth of the cathode flow channel is 0.75mm~2mm.

[0018] In a preferred embodiment of the present invention, the number of segments of the flow field is ≥3 and is an odd number.

[0019] In a preferred embodiment of the present invention, the transition zone and the bottom of the cathode flow channel are located on the same horizontal plane, and the width of the transition zone is 1 mm.

[0020] In a preferred embodiment of the present invention, the cooling flow channel is a straight flow channel or a wavy flow channel, the cooling flow channel is arranged in parallel with the cathode flow channel, and the cooling flow channel and the cathode flow channel ridge are arranged correspondingly.

[0021] In a preferred embodiment of the present invention, the depth of the cooling channel is less than or equal to the depth of the cathode channel, and the width of the cooling channel is less than or equal to the width of the cathode channel.

[0022] In a preferred embodiment of the present invention, the bipolar plate body is circumferentially provided with an anode sealing groove on the anode side, in which an anode sealing ring is embedded. The anode sealing groove cooperates with the anode sealing ring to surround the anode flow field, two anode through holes and two anode gas distribution areas to seal the hydrogen.

[0023] The bipolar plate body is provided with two cathode sealing grooves on the cathode side, the two cathode sealing grooves are respectively arranged around the two anode through holes, and cathode sealing rings are respectively embedded in the two cathode sealing grooves to seal the hydrogen.

[0024] In a preferred embodiment of the present invention, during processing, the anode side is arranged on one side of the first plate body, and the cathode side is arranged on one side of the second plate body, half of the cooling channel is arranged on the other side of the first plate body, and the other half of the cooling channel is arranged on the other side of the second plate body, and anode through holes are arranged on one side of the cooling channel of the first plate body and the second plate body, and sealing grooves are arranged accordingly, and the first plate body and the second plate body on one side of which the cooling channel is arranged are combined to constitute a cathode open air-cooled fuel cell bipolar plate.

[0025] In a preferred embodiment of the present invention, positioning holes are respectively provided at the four corners of the bipolar plate body, and voltage inspection holes are respectively provided on both sides of the length direction of the bipolar plate body, and the voltage inspection holes are located between the anode through hole and the cathode flow channel in the thickness direction.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] Compared with the conventional cathode open air-cooled fuel cell bipolar plate, the present invention improves the structure of the anode flow channel and the cathode flow channel respectively, and sets a separate cooling flow channel between the anode side and the cathode side, which improves the mass transfer characteristics and heat transfer characteristics without increasing the length and width of the bipolar plate, which is specifically reflected in:

[0028] On the anode side: A plurality of parallel anode flow channels are arranged on the anode side. The anode flow channels are arranged along the length direction of the bipolar plate body. The anode flow channels are straight flow channels or wavy flow channels, which reduce the anode inlet and outlet pressure drop while ensuring the anode flow field mass transfer efficiency.

[0029] On the cathode side: multiple flow fields are arranged on the cathode side, and the multiple flow fields are arranged along the width direction of the bipolar plate body. A transition zone is arranged between two adjacent flow fields, and each flow field includes multiple parallel cathode flow channels, which are arranged along the width direction of the bipolar plate body. In the two adjacent flow fields, the cathode flow channels are arranged in an alternating manner. The cathode flow field of the present invention adopts a flow channel segmented cross-row disturbance design, which strengthens the cathode gas disturbance, enhances the mass transfer efficiency of the cathode flow field, and greatly improves the mass transfer uniformity and temperature distribution uniformity, thereby improving the electrochemical reaction efficiency and the overall performance of the fuel cell stack.

[0030] Between the anode side and the cathode side: A plurality of parallel cooling channels are opened along the width direction on the bipolar plate body, and the cooling channels are located between the anode side and the cathode side. The present invention adds a cooling channel used solely for cooling, which plays a major cooling role and improves the temperature control level.

[0031] Through the above structural improvements, the mass transfer characteristics and heat transfer characteristics can be improved without increasing the length and width of the bipolar plate.

[0032] In addition, compared with the traditional cathode open air-cooled fuel cell bipolar plate, the present invention adopts a large-diameter anode through hole and cooperates with the design of the anode gas distribution area to ensure the uniformity of gas distribution in the anode flow channel, thereby further improving the anode flow field mass transfer efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The invention provides a cathode open air-cooled fuel cell bipolar plate.

[0034] Figure 2 Schematic diagram of the anode side structure in which the anode flow channel is a direct flow channel.

[0035] Figure 3 This is a schematic diagram of the anode side structure in which the anode flow channel is a wavy flow channel.

[0036] Figure 4 Schematic diagram of the cathode side structure in which the cathode flow channel is a direct flow channel.

[0037] Figure 5 This is a schematic diagram of the cathode side structure in which the cathode flow channel is a wavy flow channel.

[0038] Figure 6 Schematic diagram of the cross section of the bipolar plate along the thickness direction.

[0039] Figure 7 A schematic diagram of a bipolar plate formed by combining two plates.

[0040] Description of reference numerals:

[0041] 1. Anode side, 2. Cathode side, 3. Cooling channel, 4. Anode through hole, 5. Positioning hole, 6. Voltage inspection hole, 7. Anode channel, 8. Anode gas distribution area, 9. Anode sealing groove, 10. Cathode channel, 11. Cathode sealing groove, 12. Transition zone, 1-1. First plate body, 1-2. Second plate body. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0043] The present invention provides a cathode open air-cooled fuel cell bipolar plate, comprising a bipolar plate body, wherein two sides of the bipolar plate body are respectively configured as an anode side 1 and a cathode side 2.

[0044] The bipolar plate body is provided with a plurality of parallel anode flow channels 7 on the anode side 1 . The anode flow channels 7 are arranged along the length direction of the bipolar plate body. The anode flow channels 7 are straight flow channels or wavy flow channels. Hydrogen flows from one end of the anode flow channel 7 to the other end of the anode flow channel 7 .

[0045] The bipolar plate body is provided with multiple flow fields on the cathode side 2, and the multiple flow fields are arranged along the width direction of the bipolar plate body. A transition zone 12 is configured between two adjacent flow fields. Each flow field includes multiple parallel cathode flow channels 10, and the cathode flow channels 10 are arranged along the width direction of the bipolar plate body. In two adjacent flow fields, the cathode flow channels 10 are arranged in an alternating manner.

[0046] A plurality of parallel cooling channels 3 are opened between the anode side 1 and the cathode side 2. The cooling channels 3 are arranged along the width direction of the bipolar plate body, and both ends of the cooling channels 3 pass through the bipolar plate body. The cooling channels 3 and the cathode channels 10 take in air on the same side and discharge air on the same side, sharing a common air source.

[0047] The present invention sets parallel anode flow channels 7 on the anode side 1, and the anode flow channels 7 are straight channels or wavy channels, which reduce the anode inlet and outlet pressure drop while ensuring the anode flow field mass transfer efficiency. The present invention adopts a segmented cross-row disturbance flow design on the cathode side 2, which strengthens the cathode gas disturbance, enhances the cathode flow field mass transfer efficiency, and greatly improves the mass transfer uniformity and temperature distribution uniformity, thereby improving the electrochemical reaction efficiency and the overall performance of the fuel cell stack. An independent cooling channel 3 is set between the anode side 1 and the cathode side 2, and the amount of air entering the cathode flow channel 10 ensures the amount of air required for the cathode reaction while playing a partial cooling role. The main cooling function is completed by the cooling channel 3, which significantly improves the temperature control level and the cooling efficiency. Through the above-mentioned improvement strategy, the present invention can increase the convection heat exchange area of ​​the bipolar plate without increasing the length and width of the bipolar plate, and achieves a significant temperature control purpose under the condition of unchanged fan power consumption, and can control the temperature of the stack in the most ideal temperature range.

[0048] In a preferred embodiment of the present invention, compared with the conventional cathode open air-cooled fuel cell bipolar plate, the present invention also improves the anode through hole and increases the size of the anode through hole. Specifically, a plurality of parallel anode flow channels 7 constitute an anode flow field. Anode through holes 4 are respectively opened at both ends of the bipolar plate body. Anode gas distribution areas 8 are respectively arranged around the two anode through holes 4 on the anode side 1. The anode gas distribution areas 8 connect the anode through holes 4 and the anode flow field. The width of the anode gas distribution area 8 is the same as the width of the anode flow field, and the width of the anode through hole 4 is 2 mm to 4 mm smaller than the width of the anode gas distribution area 8. The large-diameter anode through hole 4 and the anode gas distribution area 8 design can ensure the uniformity of gas distribution in the anode flow channel 7. The bipolar plate of the present invention realizes efficient heat and mass transfer of the flow fields on both sides of the bipolar plate through the parallel flow channel design on the anode side, the segmented cross-row turbulence design on the cathode side, the independent cooling flow channel design, the large-diameter anode through-hole and the anode gas distribution area design, etc., greatly improves the uniformity of mass transfer and temperature distribution, increases the convection heat exchange area, achieves significant temperature control purposes under the condition of unchanged fan power consumption, can control the temperature of the battery stack in the most ideal temperature range, and improves the electrochemical reaction efficiency and the overall performance of the fuel cell stack. Compared with the traditional cathode open air-cooled fuel cell bipolar plate, the present invention can increase the convection heat exchange area of ​​the bipolar plate without increasing the length and width of the bipolar plate, and achieves significant temperature control purposes under the condition of unchanged fan power consumption, and can control the temperature of the battery stack in the most ideal temperature range. The cathode flow field adopts a segmented cross-row turbulence design, which strengthens the cathode gas turbulence, enhances the mass transfer efficiency of the cathode flow field, and greatly improves the mass transfer uniformity and temperature distribution uniformity, thereby improving the electrochemical reaction efficiency and the overall performance of the fuel cell stack. The large-diameter anode through-hole and anode gas distribution area design can ensure the uniformity of gas distribution in the anode flow channel; the anode flow channel adopts parallel flow channels, which reduces the anode inlet and outlet pressure drop while ensuring the anode flow field mass transfer efficiency.

[0049] The content of the present invention is described in detail below with reference to the accompanying drawings.

[0050] In a preferred embodiment of the present invention, Figure 1 As shown, the present invention provides a cathode open air-cooled fuel cell bipolar plate, including a bipolar plate body, on which are arranged an anode side 1, a cathode side 2, a cooling channel 3, an anode through hole 4, a positioning hole 5 and a voltage inspection hole 6. The bipolar plate body is a rectangular thin plate, and the two sides of the bipolar plate body are respectively configured as an anode side 1 and a cathode side 2, an anode through hole 4 is respectively provided at both ends of the length direction of the bipolar plate body, and a plurality of parallel cooling channels 3 are provided between the anode side 1 and the cathode side 2 in the thickness direction of the bipolar plate body, and the cooling channels 3 are arranged along the width direction of the bipolar plate body.

[0051] like Figure 2 and Figure 3 As shown, the bipolar plate body is provided with a plurality of parallel anode flow channels 7 on the anode side 1, with anode gas distribution areas 8 at both ends and anode sealing grooves 9 arranged circumferentially. The anode flow channels 7 are straight flow channels ( Figure 2 ) or parallel wave flow channel ( Figure 3 ), the width of the anode channel 7 is 0.5mm~2mm, and the anode channel ridge is configured between two adjacent anode channels 7, the width of the anode channel ridge is 0.5mm~2mm, and the depth of the anode channel 7 is 0.2mm~0.5mm. There is an anode gas distribution area 8 on each side of the anode channel 7, and the anode gas distribution area 8 is designed around the anode through-hole 4. Multiple parallel anode channels 7 constitute the anode flow field, and the anode gas distribution area 8 connects the anode flow field and the anode through-holes 4 located on both sides. The anode through-hole 4 adopts a large diameter, and the width of the anode gas distribution area 8 is the same as the width of the anode flow field. The width of the anode through-hole 4 is 2mm~4mm smaller than the width of the anode gas distribution area 8. The large-diameter anode through-hole and the anode gas distribution area design can ensure the uniformity of gas distribution in the anode channel. The anode sealing groove 9 cooperates with a sealing ring of corresponding shape for sealing. Specifically, the bipolar plate body is circumferentially provided with an anode sealing groove 9 on the anode side 1, and an anode sealing ring is embedded in the anode sealing groove 9. The anode sealing groove 9 cooperates with the anode sealing ring to surround the anode flow field, two anode through holes 4 and two anode gas distribution areas 8 to seal the hydrogen.

[0052] In a preferred embodiment of the present invention, Figure 4As shown, the bipolar plate body is provided with multiple flow fields on the cathode side 2, and the multiple flow fields are arranged along the width direction of the bipolar plate body. A transition zone 12 is arranged between two adjacent flow fields. Each flow field includes multiple parallel cathode flow channels 10, and the cathode flow channels 10 are arranged along the width direction of the bipolar plate body. In the two adjacent flow fields, the cathode flow channels 10 are arranged alternately. The cathode flow channels 10 are parallel direct current channels ( Figure 4 ) or parallel wave flow channel ( Figure 5 ), the width of the cathode flow channel 10 is 0.75mm~3mm, and the cathode flow channel ridge is configured between two adjacent cathode flow channels 10, the width of the cathode flow channel ridge is 0.5mm~2mm, and the depth of the cathode flow channel 10 is 0.75-2mm. The cathode flow channel 10 is designed in a segmented cross row in the flow field direction to strengthen the cathode flow field turbulence and enhance mass transfer and heat transfer, that is, the outlet of the cathode flow channel 10 of the previous section corresponds to the ridge of the cathode flow channel 10 of the next section, and the width of the cathode flow channel is greater than the width of the cathode flow channel ridge. In order to ensure the symmetry and uniformity of the cathode flow field, the number of flow field segments is ≥3, and it is an odd number. The larger the number of segments, the more uniform the flow field distribution, but too many segments will increase the air flow resistance to a certain extent, so it can be specifically determined according to the width of the bipolar plate. There is a transition zone 12 with a width of 1mm between the segmented flow channels. The transition zone 12 is on the same horizontal plane as the bottom of the cathode flow channel 10, which is used to transition between the front and rear flow fields and redistribute the gas and moisture between the two flow fields. The cathode sealing groove 11 is mainly arranged around the anode through hole 4 penetrating the cathode side 2, and cooperates with a sealing ring of a corresponding shape to seal the hydrogen passing through the through hole to prevent leakage to the cathode side.

[0053] In a preferred embodiment of the present invention, the cooling channel 3 is a row of channels designed separately between the anode side 1 and the cathode side 2 in the thickness direction of the bipolar plate body ( Figure 6 ), the heat dissipation area is increased on the basis of the traditional cathode open bipolar plate. The cooling channel 3 is arranged in parallel with the cathode channel 10, and is a parallel straight channel or a parallel wavy channel that runs through the width direction of the plate. In order to ensure the mechanical strength of the plate, the ridges of the cooling channel 3 and the cathode channel 10 remain vertical on the inlet and outlet sides; the depth of the cooling channel 3 is less than or equal to the depth of the cathode channel 10, and the width of the cooling channel 3 is less than or equal to the width of the cathode channel 11. The cooling channel 3 and the cathode channel 10 have air intake and air outlet on the same side, and share a wind source. The amount of air entering the cathode channel 10 ensures the amount of air required for the cathode reaction while playing a partial cooling role. The main cooling function is completed by the 3-cooling channel, which significantly improves the temperature control level.

[0054] The bipolar plate body is also provided with a positioning hole 5 and a voltage inspection hole 6. The positioning hole 5 has a diameter of 3mm to 4mm and is located at the four corners of the bipolar plate. It is a through hole that penetrates the anode side 1 and the cathode side 2 and is used to accurately position the bipolar plate during the assembly of the battery stack; the voltage inspection hole 6 has a diameter of 1mm to 1.5mm and a depth of 1mm to 2mm and is located between the anode through hole 4 and the cathode flow channel in the thickness direction of both sides of the bipolar plate.

[0055] In order to facilitate the processing and forming of the cooling channel, another preferred embodiment of the invention is to design the anode side 1 and the cathode side 2 separately on two plates, and to set half of the cooling channel 3, that is, half of the channel depth direction, on the other side of each plate, and the two plates are combined to form the above-mentioned bipolar plate. At the same time, the cooling channel side of the two plates also has an anode through hole penetrating through it, and each is provided with a sealing groove accordingly. Specifically, as Figure 7 As shown, the anode side 1 and the cathode side 2 are separately designed on one side of the first plate body 1-1 and the second plate body 1-2, half of the cooling channel 3 is provided on the other side of the first plate body 1-1, and the other half of the cooling channel 3 is provided on the other side of the second plate body 1-2. Anode through holes are provided on one side of the cooling channels of the first plate body 1-1 and the second plate body 1-2, and sealing grooves are provided accordingly. The first plate body 1-1 and the second plate body 1-2 on one side of which the cooling channels 3 are provided are combined to form a cathode open air-cooled fuel cell bipolar plate.

[0056] Compared with the open air-cooled fuel cell bipolar plate disclosed in patent CN220358139U, the present invention can increase the convection heat exchange area of ​​the bipolar plate without increasing the length and width of the bipolar plate, and achieves a significant temperature control purpose under the condition of unchanged fan power consumption, and can control the temperature of the fuel cell stack in the most ideal temperature range.

[0057] Compared with the cathode open air-cooled fuel cell bipolar plate provided by patent CN113451601A, the cathode flow field of the present invention adopts a segmented cross-shaped turbulence design, which strengthens the cathode gas turbulence, enhances the mass transfer efficiency of the cathode flow field, and greatly improves the mass transfer uniformity and temperature distribution uniformity, thereby improving the electrochemical reaction efficiency and the overall performance of the fuel cell stack.

[0058] Compared with the small-diameter anode through holes and serpentine anode flow channels of the above two patents, the present invention adopts large-diameter anode through holes and anode gas distribution area design to ensure uniform gas distribution in the anode flow channel; the anode flow channel adopts parallel flow channels, which reduces the anode inlet and outlet pressure drop while ensuring the anode flow field mass transfer efficiency.

[0059] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, they are also intended to be included.

Claims

1. A cathode open air-cooled fuel cell bipolar plate, comprising a bipolar plate body, wherein two side surfaces of the bipolar plate body are respectively configured as an anode side (1) and a cathode side (2), Features: The anode side (1) is provided with a plurality of parallel anode flow channels (7), the anode flow channels (7) are arranged along the length direction of the bipolar plate body, the anode flow channels (7) are straight flow channels or wavy flow channels, and hydrogen flows from one end of the anode flow channel (7) to the other end of the anode flow channel (7); The cathode side (2) is provided with multiple flow fields, the multiple flow fields are arranged along the width direction of the bipolar plate body, a transition zone (12) is arranged between two adjacent flow fields, each flow field includes a plurality of parallel cathode flow channels (10), the cathode flow channels (10) are arranged along the width direction of the bipolar plate body, and the cathode flow channels (10) are arranged in a staggered manner in two adjacent flow fields; A plurality of parallel cooling channels (3) are opened on the bipolar plate body between the anode side (1) and the cathode side (2), the cooling channels (3) being arranged along the width direction of the bipolar plate body, and the two ends of the cooling channels (3) respectively penetrate the bipolar plate body; the cooling channels (3) and the cathode channels (10) are inlet and outlet on the same side, and share a common air source.

2. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that An anode channel ridge is arranged between two adjacent anode channels (7), the width of the anode channel (7) is 0.5 mm to 2 mm, the width of the anode channel ridge is 0.5 mm to 2 mm, and the depth of the anode channel (7) is 0.2 mm to 0.5 mm.

3. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that A plurality of parallel anode flow channels (7) form an anode flow field. Anode through holes (4) are respectively provided at both ends of the bipolar plate body. Anode gas distribution areas (8) are respectively arranged on the periphery of the two anode through holes (4) on the anode side (1). The anode gas distribution areas (8) connect the anode through holes (4) and the anode flow field. The width of the anode gas distribution area (8) is the same as the width of the anode flow field, and the width of the anode through hole (4) is 2 mm to 4 mm smaller than the width of the anode gas distribution area (8).

4. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that The cathode flow channel (10) is a straight flow channel or a wavy flow channel, and a cathode flow channel ridge is arranged between two adjacent cathode flow channels (10). The width of the cathode flow channel (10) is 0.75 mm to 3 mm, the width of the cathode flow channel ridge is 0.5 mm to 2 mm, and the width of the cathode flow channel (10) is greater than the width of the cathode flow channel ridge. The depth of the cathode flow channel (10) is 0.75 mm to 2 mm.

5. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that The number of flow field segments is at least 3 and is an odd number.

6. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that The transition zone (12) and the bottom of the cathode flow channel (10) are located on the same horizontal plane, and the width of the transition zone (12) is 1 mm.

7. The cathode open air-cooled fuel cell bipolar plate according to claim 4, It is characterized in that The cooling flow channel (3) is a straight flow channel or a wavy flow channel, the cooling flow channel (3) is arranged in parallel with the cathode flow channel (10), and the cooling flow channel (3) is arranged corresponding to the ridge of the cathode flow channel.

8. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that The depth of the cooling channel (3) is less than or equal to the depth of the cathode channel (10), and the width of the cooling channel (3) is less than or equal to the width of the cathode channel (10).

9. The cathode open air-cooled fuel cell bipolar plate according to claim 3, It is characterized in that The bipolar plate body is provided with an anode sealing groove (9) in the circumferential direction on the anode side (1), an anode sealing ring is embedded in the anode sealing groove (9), and the anode sealing groove (9) cooperates with the anode sealing ring to surround the anode flow field, two anode through holes (4) and two anode gas distribution areas (8) to seal the hydrogen; The bipolar plate body is provided with two cathode sealing grooves (11) on the cathode side (2), the two cathode sealing grooves (11) are respectively arranged around the two anode through holes (4), and cathode sealing rings are respectively embedded in the two cathode sealing grooves (11) to seal the hydrogen.

10. The cathode open air-cooled fuel cell bipolar plate according to claim 1, It is characterized in that During processing, the anode side (1) is arranged on one side of the first plate body (1-1), and the cathode side (2) is arranged on one side of the second plate body (1-2); the other side of the first plate body (1-1) is provided with half of the cooling channel (3); the other side of the second plate body (1-2) is provided with the other half of the cooling channel (3); the first plate body (1-1) and the second plate body (1-2) are combined on the side provided with the cooling channel (3) to form a cathode open air-cooled fuel cell bipolar plate.

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