CN109643809B - Engaged ultrathin metal bipolar plate and three-dimensional flow field thereof - Google Patents
Engaged ultrathin metal bipolar plate and three-dimensional flow field thereof Download PDFInfo
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- CN109643809B CN109643809B CN201880002721.2A CN201880002721A CN109643809B CN 109643809 B CN109643809 B CN 109643809B CN 201880002721 A CN201880002721 A CN 201880002721A CN 109643809 B CN109643809 B CN 109643809B
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- 239000002184 metal Substances 0.000 title claims abstract description 53
- 239000000446 fuel Substances 0.000 abstract description 24
- 238000013461 design Methods 0.000 abstract description 16
- 239000000110 cooling liquid Substances 0.000 abstract description 4
- 239000000112 cooling gas Substances 0.000 abstract description 3
- 230000005540 biological transmission Effects 0.000 abstract 1
- 239000002737 fuel gas Substances 0.000 abstract 1
- 239000012528 membrane Substances 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000005404 monopole Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0204—Non-porous and characterised by the material
- H01M8/0206—Metals or alloys
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
- H01M8/026—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant characterised by grooves, e.g. their pitch or depth
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/02—Details
- H01M8/0202—Collectors; Separators, e.g. bipolar separators; Interconnectors
- H01M8/0258—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
- H01M8/0265—Collectors; Separators, e.g. bipolar separators; Interconnectors characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant the reactant or coolant channels having varying cross sections
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Fuel Cell (AREA)
Abstract
The meshed ultrathin metal bipolar plate for the fuel cell comprises two metal unipolar plates (1), wherein a plurality of sunken flow channels (2) are arranged on the metal unipolar plates and are used as flow field grooves, flow field ridges are arranged between the adjacent flow channels, the cross sections of the flow channels in the width direction are trapezoidal, the cross sections of the flow channels in the length direction are wavy, the flow field ridge of one unipolar plate is inserted into the flow field groove of the other unipolar plate, and the two metal unipolar plates are meshed at the wavy wave troughs. The metal bipolar plate can realize three-dimensional transmission of fuel gas on one hand, and meshed combination between two unipolar plates on the other hand through the trough of the trapezoidal wave flow field, and a flow field of cooling liquid can be formed in the hollow part of the bipolar plate by utilizing the crest of the wavy flow field. Through the design of the meshed metal bipolar plate, the thickness of the bipolar plate can be further reduced, the design and the forming of the ultrathin metal bipolar plate are realized, and meanwhile, the flow field of cooling liquid or cooling gas is reserved.
Description
Technical Field
The utility model relates to the technical field of metal bipolar plates and flow field design for proton exchange membrane fuel cells, in particular to a meshed metal bipolar plate for a fuel cell and a three-dimensional flow field thereof.
Background
Currently, air pollution has been increasingly worsened, and environmental issues have been increasingly emphasized by the nation. In the aspect of automobiles, many countries internationally set up a time schedule for exiting a history stage of a traditional fuel vehicle, so that new energy automobiles become one of the national development strategies. The proton exchange membrane fuel cell taking hydrogen as fuel can directly convert chemical energy in the hydrogen into electric energy, only discharges water in the process, is a green power generation device for hydrogen energy utilization, can be used as a driving power supply of an electric automobile, and has been industrialized internationally.
The bipolar plate is one of the key components of the vehicle fuel cell, and due to the space limitation of a car, the requirement on the volume power density of the vehicle fuel cell is high, so that the thickness of the bipolar plate is required to be thin, so that the volume of the vehicle fuel cell is reduced as much as possible under the condition of keeping the same output power, namely, the volume power density of the vehicle fuel cell is improved. Under the condition that the thickness of the bipolar plate is reduced, the traditional graphite bipolar plate or the composite bipolar plate cannot be applied due to factors such as mechanical property, gas permeability and the like, and a metal material is required to be used for preparing the bipolar plate. In the existing metal bipolar plate design, a flow field groove is designed based on a rectangular section, two metal unipolar plates with rectangular sections are combined in a 'meshing' mode to prepare a metal bipolar plate, ridge parts of the two unipolar plates form a hollow part in the middle of the bipolar plate, and therefore a flow field of cooling liquid or cooling gas is formed. If the flow field with the rectangular cross section is assembled in a meshing mode, the hollow flow field for cooling is closed, and the fuel cell cannot be cooled. In order to further improve the volumetric power density of the vehicle fuel cell, the flow field design of the metal bipolar plate needs to be improved, the thickness of the metal bipolar plate is reduced while the flow field is optimized, so that the volume of the vehicle fuel cell is reduced while the output power of the vehicle fuel cell is maintained, and the purpose of improving the volumetric power density of the vehicle fuel cell is achieved.
Disclosure of Invention
The utility model aims to solve the problems in the prior art and provide an engaged metal bipolar plate for a fuel cell, which can effectively reduce the thickness of the metal bipolar plate, keep the output power and reduce the volume of the fuel cell for a vehicle by designing a three-dimensional flow field of the metal bipolar plate, thereby realizing the purpose of improving the volume power density of the fuel cell for the vehicle.
In order to achieve the purpose, the technical scheme of the utility model is as follows:
the meshed ultrathin metal bipolar plate comprises two metal unipolar plates, wherein a plurality of downward-recessed flow channels are arranged on the metal unipolar plates, the flow channels are used as flow field grooves, the part between every two adjacent flow channels is a flow field ridge, the cross section of each flow channel along the width direction is trapezoidal, the cross section of each flow channel along the length direction is wavy, the flow field grooves and the flow field ridges of the two metal unipolar plates are mutually alternated, namely the flow field ridge of one unipolar plate is inserted into the flow field groove of the other unipolar plate, and the two metal unipolar plates are meshed at the wavy trough.
The lower bottom of the trapezoid is the upper part of the flow channel, the upper bottom of the trapezoid is the lower part of the flow channel, and the ridge-groove ratio of the flow field is controlled by changing the lengths of the upper bottom and the lower bottom of the trapezoid.
The wave-shaped equation is a sine function or a cosine function.
The upper bottom and the lower bottom of the trapezoidal section of the flow field groove are respectively the same as the upper bottom and the lower bottom of the flow field ridge.
The utility model has the technical effects that:
the utility model provides a metal bipolar plate for a fuel cell and a three-dimensional flow field design scheme thereof.A flow field design with trapezoidal and sine curves or cosine curves in section is adopted, the ridge-groove ratio of the flow field can be effectively controlled through the trapezoidal section design, and a unipolar plate with two flow field grooves and ridges which are mutually alternated is combined into a bipolar plate in a meshing manner at the trough of the sine or cosine curves through the wavy section design, so that the thickness of the metal bipolar plate is the thickness of two metal plates plus the depth of the flow field groove, the thickness of the depth of the flow field groove can be effectively reduced, and the ultrathin metal bipolar plate is obtained; meanwhile, because of the adoption of the design of sine or cosine curve section, a space is reserved at the peak position, and a flow field of cooling liquid or cooling gas in the hollow part of the metal bipolar plate is formed. Because the unipolar plate design that two kinds of flow field grooves and ridges alternate with each other is adopted, when the cell stack is assembled, the positions of the flow field grooves and the ridges of the metal bipolar plates on the two sides of the membrane electrode of the fuel cell need to be ensured to be the same and can not alternate, and if the flow field grooves and the ridges are alternately arranged, the membrane electrode can be damaged by shearing force. Compared with the traditional metal bipolar plate designed in a 'meshing' mode, the meshing type ultra-thin metal bipolar plate can effectively reduce the thickness of the bipolar plate, reduce the volume of a fuel cell stack for a vehicle and improve the volume power density.
The utility model effectively reduces the depth of one flow field groove of the metal bipolar plate and realizes the design of a thinner metal bipolar plate by improving the design of the traditional meshed metal bipolar plate into the meshed design, thereby achieving the purposes of reducing the volume of the fuel cell stack and improving the volume power density of the fuel cell stack for the vehicle under the condition of keeping the output power of the fuel cell stack for the vehicle unchanged.
Drawings
The utility model will be further explained with reference to the drawings
FIG. 1 is a cross-sectional view of a bipolar plate according to the present invention taken along the width direction thereof;
FIG. 2 is a schematic view of a flow field configuration of a bipolar plate according to the present invention;
FIG. 3 is a schematic cross-sectional view of a trapezoidal shape in the flow channel width direction;
FIG. 4 is a sectional view in the longitudinal direction of the flow path;
fig. 5 is a schematic lengthwise view of a metallic bipolar plate.
Detailed Description
The utility model is further described below by way of examples.
Example 1
The utility model provides an engagement type ultra-thin metal bipolar plate, includes two metal unipolar plates 1, has a plurality of recessed runners 2 on the metal unipolar plate 1, runner 2 is as the flow field groove, the part between adjacent runner 2 is the flow field ridge, runner 2 is trapezoidal along the cross-section of width direction, the cross-section along length direction is the wave, the flow field groove of two metal unipolar plates 1 and flow field ridge are each other alternate, namely the part of a unipolar plate flow field groove corresponds the part of another unipolar plate flow field ridge, two metal unipolar plates mesh in "wave" trough department. The wave equation is a sine function or a cosine function, in this embodiment a sine function.
The processing method comprises the following steps:
step 1, using a metal plate with the thickness of 0.1mm as a metal monopole plate base material;
the cross sections of flow channels are respectively in a trapezoid shape and a wave shape, and a flow field plate is shown as an attached drawing 1;
the length of the upper bottom and the length of the lower bottom of the isosceles trapezoid cross section are respectively 0.5mm and 0.8mm, namely the groove width of the surface of the flow field plate is 0.8mm, and the ridge width is 0.5mm, as shown in the attached figures 1 and 2;
③ the wave-shaped section equation is 0.12 × sin (x), the maximum depth of the runner groove is 0.4mm, and the minimum depth is 0.16mm, as shown in the attached drawings 1 and 3;
step 3, designing a flow field plate drawing with the positions opposite to those of the flow field grooves and the flow field ridges in the step 2;
step 4, respectively processing corresponding stamping dies based on the designs in the steps 2 and 3;
step 5, respectively using the dies in the step 4 to punch and form the metal plate in the step 1;
and 6, combining the two unipolar plates punched based on the steps 2 and 3 in a meshing manner at the positions of the wave troughs, and obtaining the meshing type ultrathin metal bipolar plate as shown in the attached figure 4.
Example 2:
the equation for the waveform in this embodiment is a cosine function.
Step 1, using a metal plate with the thickness of 0.1mm as a base material;
firstly, the cross sections of the flow passages are respectively in a trapezoidal shape and a wave shape;
the length of the upper bottom of the isosceles trapezoid cross section is 0.6mm, the length of the lower bottom is 1mm, namely the groove width of the surface of the flow field plate is 1mm, and the ridge width is 0.6 mm; thirdly, the wave-shaped cross section equation is 0.1 × cos (x), the maximum depth of the runner groove is 0.4mm, and the minimum depth is 0.2 mm;
step 3, designing a flow field plate drawing with the positions opposite to those of the flow field grooves and the flow field ridges in the step 2;
step 4, respectively processing corresponding stamping dies based on the designs in the steps 2 and 3;
step 5, respectively using the dies in the step 4 to punch and form the metal plate in the step 1;
and 6, combining the two unipolar plates punched based on the steps 2 and 3 in a meshing manner at the positions of the wave troughs to obtain the meshed ultra-thin metal bipolar plate.
It is to be emphasized that: the above embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and all simple modifications, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention are within the scope of the technical solution of the present invention.
Claims (4)
1. The meshed metal bipolar plate comprises two metal unipolar plates, wherein a plurality of sunken flow channels are arranged on the metal unipolar plates, the flow channels are used as flow field grooves, and the part between every two adjacent flow channels is a flow field ridge.
2. The engaged metallic bipolar plate of claim 1, wherein the lower bottom of said trapezoid is the upper portion of said flow channel, and the upper bottom of said trapezoid is the lower portion of said flow channel, and the ridge-to-groove ratio of said flow field is controlled by varying the length of said upper bottom and said lower bottom of said trapezoid.
3. The intermeshing metal bipolar plate of claim 1, wherein the equation for the waviness is a sine function or a cosine function.
4. The engaged metallic bipolar plate of claim 1, wherein the upper and lower bottoms of the trapezoidal cross-section of the flow field grooves are identical to the upper and lower bottoms of the flow field ridges, respectively.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/CN2018/079264 WO2019174028A1 (en) | 2018-03-16 | 2018-03-16 | Engagement-type ultra-thin metal bipolar plate and three-dimensional flow field thereof |
Publications (2)
Publication Number | Publication Date |
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CN109643809A CN109643809A (en) | 2019-04-16 |
CN109643809B true CN109643809B (en) | 2022-04-01 |
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CN201880002721.2A Expired - Fee Related CN109643809B (en) | 2018-03-16 | 2018-03-16 | Engaged ultrathin metal bipolar plate and three-dimensional flow field thereof |
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CN (1) | CN109643809B (en) |
WO (1) | WO2019174028A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102022106045A1 (en) | 2022-03-16 | 2023-09-21 | Schaeffler Technologies AG & Co. KG | Bipolar plate for a fuel cell stack |
CN114976099A (en) * | 2022-04-27 | 2022-08-30 | 同济大学 | Fuel cell bipolar plate flow channel optimization design method |
CN115528267B (en) * | 2022-09-20 | 2023-08-15 | 中国科学院宁波材料技术与工程研究所 | Flow field plate, fuel cell unit, fuel cell, power generation system and electric equipment |
CN117543042B (en) * | 2024-01-10 | 2024-04-09 | 武汉理工大学 | Fuel cell material flow field plate with adjustable modularized three-dimensional hierarchical pore structure and cell |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104868129A (en) * | 2015-05-26 | 2015-08-26 | 昆山弗尔赛能源有限公司 | Metal bipolar plate for proton exchange membrane fuel cell |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
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US20050064270A1 (en) * | 2003-09-24 | 2005-03-24 | Marianowski Leonard G. | Fuel cell bipolar separator plate |
US7309540B2 (en) * | 2004-05-21 | 2007-12-18 | Sarnoff Corporation | Electrical power source designs and components |
GB2509319A (en) * | 2012-12-27 | 2014-07-02 | Intelligent Energy Ltd | Fluid flow plate for a fuel cell |
CN104051771B (en) * | 2013-03-15 | 2018-11-02 | 福特全球技术公司 | Fuel cell pack and vehicle including it |
CN203607487U (en) * | 2013-12-02 | 2014-05-21 | 新源动力股份有限公司 | Metal bipolar plate with high integration degree for proton exchange membrane fuel cell |
BR112016030212A2 (en) * | 2014-06-27 | 2017-08-22 | Nuvera Fuel Cells Llc | ELECTROCHEMICAL CELL, FLOW FIELD AND OPEN POROUS FLOW FIELD MANUFACTURE METHOD FOR USE IN IT |
JP2018018768A (en) * | 2016-07-29 | 2018-02-01 | トヨタ車体株式会社 | Manufacturing method of gas passage formation plate for fuel cell, and gas passage formation plate for fuel cell |
CN107634240A (en) * | 2017-09-04 | 2018-01-26 | 苏州中氢能源科技有限公司 | A kind of small fuel cell metal double polar plates |
-
2018
- 2018-03-16 WO PCT/CN2018/079264 patent/WO2019174028A1/en active Application Filing
- 2018-03-16 CN CN201880002721.2A patent/CN109643809B/en not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104868129A (en) * | 2015-05-26 | 2015-08-26 | 昆山弗尔赛能源有限公司 | Metal bipolar plate for proton exchange membrane fuel cell |
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CN109643809A (en) | 2019-04-16 |
WO2019174028A1 (en) | 2019-09-19 |
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