CN114551916A - Fuel cell stack - Google Patents

Fuel cell stack Download PDF

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Publication number
CN114551916A
CN114551916A CN202210175724.4A CN202210175724A CN114551916A CN 114551916 A CN114551916 A CN 114551916A CN 202210175724 A CN202210175724 A CN 202210175724A CN 114551916 A CN114551916 A CN 114551916A
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CN
China
Prior art keywords
fuel cell
plate
frame
cathode plate
anode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210175724.4A
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Chinese (zh)
Inventor
王猛
张华农
高鹏然
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Center Power Tech Co Ltd
Shenzhen Hydrogen Fuel Cell Technology Co Ltd
Original Assignee
Shenzhen Center Power Tech Co Ltd
Shenzhen Hydrogen Fuel Cell Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Center Power Tech Co Ltd, Shenzhen Hydrogen Fuel Cell Technology Co Ltd filed Critical Shenzhen Center Power Tech Co Ltd
Priority to CN202210175724.4A priority Critical patent/CN114551916A/en
Publication of CN114551916A publication Critical patent/CN114551916A/en
Pending legal-status Critical Current

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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
    • 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
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/1004—Fuel cells with solid electrolytes characterised by membrane-electrode assemblies [MEA]
    • 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
    • H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
    • H01M8/2465—Details of groupings of fuel cells
    • 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 fuel cell stack comprises a plurality of fuel cell units connected in series, wherein each fuel cell unit comprises a first fuel cell unit and a second fuel cell unit which are connected in series; the first fuel cell unit comprises a first upper frame, a first cathode plate, a first membrane assembly, a first anode plate and a first insulating frame which are arranged from top to bottom; the second fuel battery unit comprises a second insulating frame, a second cathode plate, a second membrane assembly, a second anode plate and a first lower frame which are arranged from top to bottom; the first anode plate and the second cathode plate are integrally formed; the second membrane assembly is abutted with the first insulating frame; the first membrane assembly is abutted against the second insulating frame. The bipolar plate has a left structure and a right structure, and can be fine in effective area of the bipolar plate, so that the power density of the fuel cell is improved, the contact resistance of the bipolar plate with the traditional upper structure and the lower structure is eliminated, and the ohmic impedance of the fuel cell is effectively reduced.

Description

Fuel cell stack
Technical Field
The invention relates to the technical field of fuel cells, in particular to a fuel cell stack.
Background
The fuel cell, which uses chemical conversion of fuel and oxygen to generate water for generating electric power, includes a membrane electrode unit as a core component. The membrane electrode unit is a united body composed of a membrane that can conduct protons and electrodes (anode and cathode) respectively disposed on both sides of the membrane. Furthermore, Gas Diffusion Layers (GDLs) may be provided on both sides of the membrane electrode unit, arranged on the side of the electrodes facing away from the membrane. A fuel cell is generally composed of a large number of membrane electrode units arranged in a stack, the electrical power of which is superimposed on one another.
In fuel cell operation, fuel, especially hydrogen H2Or the hydrogen-containing gas mixture is directed to the anode where H is carried out2To H+To release electrons. The protons H are separated from one another by an electrolyte or by an electrically insulating membrane which hermetically separates the reaction chambers+Transport (with or without water) from the anode chamber to the cathode chamber, and electrons produced at the anode are directed through the electrical circuit to the cathode. Oxygen or a gas mixture containing oxygen is directed to the cathode to complete the reaction from O by absorbing electrons2To O2-While in the cathode compartment the oxygen ions react with protons transported through the membrane to produce water. Compared to other power generation systems, fuel cells convert chemical energy directly into electrical energy, achieving better efficiency due to the elimination of the carnot factor.
The traditional fuel cell is formed by stacking a plurality of bipolar plate membrane electrode units, a cooling water flow field in the bipolar plate is formed by bonding two unipolar plates with water flow channels, and the bipolar plate with the structure has contact resistance between a cathode plate and an anode plate and larger ohmic loss because the two unipolar plates are attached into one bipolar plate.
Disclosure of Invention
Based on the above, the invention provides a fuel cell stack, which aims to solve the problems of large contact resistance, large ohmic loss of a cell and the like of the traditional fuel cell due to the fact that a polar plate and a membrane electrode are stacked up and down. The utility model provides a can effectively improve the effective area and the power density of polar plate under the prerequisite that does not influence the air current distribution homogeneity, eliminate the negative and positive plate because pile up the contact resistance that produces from top to bottom, effectively reduce fuel cell's ohmic impedance, further improve fuel cell's power density.
To achieve the above object, the present invention provides a fuel cell stack including a plurality of fuel cell units connected in series, the fuel cell units including a first fuel cell unit and a second fuel cell unit connected in series;
the first fuel cell unit comprises a first upper frame, a first cathode plate, a first membrane assembly, a first anode plate and a first insulating frame which are arranged from top to bottom;
the second fuel battery unit comprises a second insulating frame, a second cathode plate, a second membrane assembly, a second anode plate and a first lower frame which are arranged from top to bottom;
the first anode plate and the second cathode plate are integrally formed;
the second membrane assembly is abutted with the first insulating frame; the first membrane assembly is abutted against the second insulating frame.
Further, the fuel cell stack further comprises a third anode plate integrally formed with the first cathode plate, and the third anode plate is abutted against the second insulating frame; the third anode plate is connected with the anode of the load.
Furthermore, a second upper frame integrally formed with the first upper frame is arranged at the top end of the third anode plate, and the second upper frame is abutted to the third anode plate.
Further, the fuel cell stack also comprises a third cathode plate which is integrally formed with the second anode plate, and the third cathode plate is abutted with the first insulating frame; and the third cathode plate is connected with a negative electrode of a load. Therefore, the third anode plate and the third cathode plate are connected with the anode and the cathode of the load to play a role in conducting electricity.
Furthermore, a second lower frame integrally formed with the first lower frame is arranged at the bottom end of the third cathode plate, and the second lower frame is abutted to the third cathode plate.
Further, the first membrane assembly comprises a first carbon paper, a first proton membrane and a second carbon paper which are arranged from top to bottom; the second membrane assembly comprises third carbon paper, a second proton membrane and fourth carbon paper which are arranged from top to bottom.
Further, second insulating frames are arranged between the first cathode plate and the first anode plate and between the second cathode plate and the second anode plate; the second insulating frame is arranged at the edges of the first cathode plate and the first anode plate, or the second insulating frame is arranged at the edges of the second cathode plate and the second anode plate.
Further, the edge is an area 3mm to 6mm from the boundary of the first cathode plate/the first anode plate/the second cathode plate/the second anode plate.
Furthermore, first sealant lines are arranged on the first insulating frame and the second insulating frame.
Furthermore, second sealing glue lines are arranged between the first cathode plate and the first upper frame, between the third anode plate and the second upper frame, between the third cathode plate and the second lower frame, and between the second anode plate and the first lower frame.
Further, the first fuel cell unit and the second fuel cell unit have flow passages provided independently of each other; the flow channels include a hydrogen flow channel, an oxygen flow channel and a cooling liquid flow channel.
Furthermore, cooling liquid flow channels are arranged on the side face, close to the first upper frame, of the first negative plate, on the side face, close to the second insulating frame, of the second negative plate and on the side face, close to the first insulating frame, of the third negative plate.
Further, hydrogen flow channels are arranged on the side face, close to the first membrane assembly, of the first cathode plate, the side face, close to the second membrane assembly, of the second cathode plate, and the side face, close to the second lower frame, of the third cathode plate.
Further, an oxygen flow channel is arranged on the side surface of the first anode plate close to the first membrane assembly, on the side surface of the second anode plate close to the second membrane assembly and on the side surface of the third anode plate close to the second upper frame.
Compared with the prior art, the method has the following technical effects: the bipolar plate is changed into a left-right structure from an upper structure, so that the fuel cell polar plate is changed into a square structure from a long and narrow structure, the effective area of the polar plate can be well increased on the premise of not influencing the distribution uniformity of air flow, and the power density of the fuel cell is increased; because the bipolar plate adopts the left and right structure of integrated into one piece, has eliminated the contact resistance of the bipolar plate of traditional upper and lower structure, effectively reduces the ohmic impedance of fuel cell to the whole power density of fuel cell pile has further been improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a schematic diagram showing a longitudinal cross-sectional structure of a fuel cell stack according to an embodiment of the present invention;
FIG. 2 is a schematic longitudinal cross-sectional view of a first fuel cell unit of the fuel cell stack of FIG. 1;
fig. 3 is a schematic longitudinal sectional view of a second fuel cell unit of the fuel cell stack of fig. 1.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that, if directional indications (such as up, down, left, right, front, back, top and bottom … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.
In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and encompass, for example, both fixed and removable connections or integral parts thereof; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.
In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
At present, the traditional fuel cell is formed by stacking a plurality of bipolar plate membrane electrodes, a cooling water flow field in the bipolar plate is formed by bonding two unipolar plates with water flow channels, and the bipolar plate with the structure is attached into a bipolar plate by using the two unipolar plates, so that contact resistance exists between a cathode plate and an anode plate, and ohmic loss of the fuel cell is increased. Based on this, it is necessary to provide a fuel cell stack to solve the above technical problems.
The invention provides a fuel cell stack, which aims to solve the problems of large contact resistance, large ohmic loss of a cell and the like of the traditional fuel cell due to the fact that a polar plate and a membrane electrode are stacked up and down. The utility model provides a can effectively improve the effective area and the power density of polar plate under the prerequisite that does not influence the air current distribution homogeneity, eliminate the negative and positive plate because pile up the contact resistance that produces from top to bottom, effectively reduce fuel cell's ohmic impedance, further improve fuel cell pile's whole power density.
Specifically, as shown in fig. 1 to 3, an embodiment of the present invention provides a fuel cell stack including a plurality of fuel cell units connected in series, the fuel cell units including a first fuel cell unit 10 and a second fuel cell unit 20 connected in series;
the first fuel cell unit 10 comprises a first upper frame 11, a first cathode plate 12, a first membrane assembly 13, a first anode plate 14 and a first insulating frame 15 which are arranged from top to bottom;
the second fuel battery unit 20 comprises a second insulating frame 21, a second cathode plate 22, a second membrane assembly 23, a second anode plate 24 and a first lower frame 25 which are arranged from top to bottom;
the first anode plate 14 and the second cathode plate 22 are integrally formed;
the second membrane assembly 23 is abutted against the first insulating frame 15; the first diaphragm assembly 13 abuts against the second insulating frame 21.
Further, the fuel cell stack further comprises a third anode plate 30 integrally formed with the first cathode plate 12, wherein the third anode plate 30 abuts against the second insulating frame 21; the third anode plate 30 is connected to the positive electrode of a load (not shown).
Further, a second upper frame 40 integrally formed with the first upper frame 11 is disposed at the top end of the third anode plate 30, and the second upper frame 40 abuts against the third anode plate 30.
Further, the fuel cell stack further includes a third cathode plate 50 integrally formed with the second anode plate 24, and the third cathode plate 50 abuts against the first insulating frame 15; the third cathode plate 50 is connected to the negative electrode of the load. Therefore, the third anode plate and the third cathode plate are connected with the anode and the cathode of the load to play a role in conducting electricity.
Further, a second lower frame 60 integrally formed with the first lower frame 25 is disposed at the bottom end of the third cathode plate 50, and the second lower frame 60 abuts against the third cathode plate 50.
Further, the first membrane module 13 includes a first carbon paper 131, a first proton membrane 132, and a second carbon paper 133, which are disposed from top to bottom; the second membrane module 23 includes a third carbon paper 231, a second proton membrane 232, and a fourth carbon paper 233 arranged from top to bottom.
Further, third insulating frames 70 are arranged between the first cathode plate 12 and the first anode plate 14 and between the second cathode plate 22 and the second anode plate 24; the third insulating frame 70 is disposed at the edges of the first cathode plate 12 and the first anode plate 14, or the third insulating frame 70 is disposed at the edges of the second cathode plate 22 and the second anode plate 24.
Further, the edge is an area 3mm-6mm from the boundary of the first cathode plate 12/the first anode plate 14/the second cathode plate 22/the second anode plate 24.
Further, the first insulating frame 15, the second insulating frame 21, and the third insulating frame 70 are all provided with a first sealant line 80.
Further, second sealant lines 90 are disposed between the first cathode plate 12 and the first upper frame 11, between the third anode plate 30 and the second upper frame 40, between the third cathode plate 50 and the second lower frame 60, and between the second anode plate 24 and the first lower frame 25.
Further, the first fuel cell unit 10 and the second fuel cell unit 20 have flow passages provided independently of each other; the flow channels comprise a hydrogen flow channel A, an oxygen flow channel B and a cooling liquid flow channel C.
Further, a cooling liquid flow passage C is provided on the side of the first cathode plate 12 close to the first upper frame 11, on the side of the second cathode plate 22 close to the second insulating frame 70, and on the side of the third cathode plate 50 close to the first insulating frame 15.
Further, a hydrogen flow channel a is provided on the side of the first cathode plate 12 close to the first membrane module 13, on the side of the second cathode plate 22 close to the second membrane module 23, and on the side of the third cathode plate 50 close to the second lower frame 60.
Further, oxygen flow channels B are arranged on the side of the first anode plate 14 close to the first membrane module 13, the side of the second anode plate 24 close to the second membrane module 23, and the side of the third anode plate 30 close to the second upper frame 40.
The bipolar plate is changed into a left-right structure from an upper structure, so that the fuel cell polar plate is changed into a square structure from a long and narrow structure, the effective area of the polar plate can be well increased on the premise of not influencing the distribution uniformity of air flow, and the power density of the fuel cell is increased; because the bipolar plate adopts the left and right structure of integrated into one piece, has eliminated the contact resistance of the bipolar plate of traditional upper and lower structure, effectively reduces the ohmic impedance of fuel cell to the whole power density of fuel cell pile has further been improved.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. A fuel cell stack comprising a plurality of fuel cell units connected in series, the fuel cell units comprising a first fuel cell unit and a second fuel cell unit connected in series;
the first fuel cell unit comprises a first upper frame, a first cathode plate, a first membrane assembly, a first anode plate and a first insulating frame which are arranged from top to bottom;
the second fuel battery unit comprises a second insulating frame, a second cathode plate, a second membrane assembly, a second anode plate and a first lower frame which are arranged from top to bottom;
the first anode plate and the second cathode plate are integrally formed;
the second membrane assembly is abutted with the first insulating frame; the first membrane assembly is abutted against the second insulating frame.
2. The fuel cell stack of claim 1 further comprising a third anode plate integrally disposed with the first cathode plate, the third anode plate abutting the second insulating frame; the third anode plate is connected with the anode of the load; and a second upper frame integrally formed with the first upper frame is arranged at the top end of the third anode plate, and the second upper frame is abutted against the third anode plate.
3. The fuel cell stack of claim 2 further comprising a third cathode plate integrally disposed with the second anode plate, the third cathode plate abutting the first insulating frame; the third cathode plate is connected with a negative electrode of a load;
the bottom end of the third negative plate is provided with a second lower frame which is integrally formed with the first lower frame, and the second lower frame is abutted to the third negative plate.
4. The fuel cell stack of claim 3 wherein the first membrane module comprises a first carbon paper, a first proton membrane, and a second carbon paper arranged from top to bottom; the second membrane assembly comprises third carbon paper, a second proton membrane and fourth carbon paper which are arranged from top to bottom.
5. The fuel cell stack according to claim 4, wherein a second insulating frame is provided between the first cathode plate and the first anode plate, and between the second cathode plate and the second anode plate; the second insulating frame is arranged at the edges of the first cathode plate and the first anode plate, or the second insulating frame is arranged at the edges of the second cathode plate and the second anode plate.
6. The fuel cell stack according to claim 5, wherein a first sealant line is disposed on each of the first and second insulating frames;
second sealant lines are arranged between the first negative plate and the first upper frame, between the third positive plate and the second upper frame, between the third negative plate and the second lower frame and between the second positive plate and the first lower frame.
7. The fuel cell stack according to claim 6, wherein the first fuel cell unit and the second fuel cell unit have flow channels provided independently of each other; the flow channels include a hydrogen flow channel, an oxygen flow channel and a cooling liquid flow channel.
8. The fuel cell stack of claim 7 wherein coolant flow channels are provided on the side of the first cathode plate adjacent the first upper frame, on the side of the second cathode plate adjacent the second insulating frame, and on the side of the third cathode plate adjacent the first insulating frame.
9. The fuel cell stack of claim 8 wherein a hydrogen flow channel is provided on a side of the first cathode plate adjacent to the first membrane assembly, on a side of the second cathode plate adjacent to the second membrane assembly, and on a side of the third cathode plate adjacent to the second lower frame.
10. The fuel cell stack of claim 9 wherein oxygen flow channels are provided on a side of the first anode plate adjacent to the first membrane modules, on a side of the second anode plate adjacent to the second membrane modules, and on a side of the third anode plate adjacent to the second upper frame.
CN202210175724.4A 2022-02-25 2022-02-25 Fuel cell stack Pending CN114551916A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210175724.4A CN114551916A (en) 2022-02-25 2022-02-25 Fuel cell stack

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210175724.4A CN114551916A (en) 2022-02-25 2022-02-25 Fuel cell stack

Publications (1)

Publication Number Publication Date
CN114551916A true CN114551916A (en) 2022-05-27

Family

ID=81680240

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210175724.4A Pending CN114551916A (en) 2022-02-25 2022-02-25 Fuel cell stack

Country Status (1)

Country Link
CN (1) CN114551916A (en)

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