A thermal management component for fuel cells based on a rollable heat spreader.

Abstract

This invention proposes a fuel cell thermal management component based on a rollable heat spreader, including a fuel cell, an external temperature control module, and a temperature detection module. The fuel cell contains one or more rollable heat spreaders. The temperature of the rollable heat spreaders is controlled by the external temperature control module and the temperature detection module. The heat spreader's uniform temperature characteristics are utilized for effective thermal management of the fuel cell. The fuel cell casing has slots into which the rollable heat spreader is inserted. The heat spreader is divided into a uniform temperature section in contact with the current collector casing and a temperature control section exposed to the fuel cell. During fuel cell operation, this invention utilizes the uniform temperature characteristics of the rollable heat spreader inserted into the current collector casing slots to prevent localized overheating and damage within the fuel cell. Furthermore, it regulates the temperature of the fuel cell stack by heating or cooling the exposed temperature control section based on the real-time temperature distribution inside the battery.

Description

Technical Field

[0001] This invention relates to the field of fuel cell thermal management, and in particular to a fuel cell thermal management component based on a rollable heat spreader. Background Technology

[0002] Currently, the world faces two major challenges: the energy crisis and environmental pollution. Fuel cells are a common way to utilize hydrogen energy, offering advantages such as clean products, high power density and energy conversion efficiency, and the ability to obtain fuel from biomass, thus possessing promising and broad application prospects. Traditional fuel cells generally adopt a planar plate-and-frame structure, which has disadvantages such as large weight and volume, and high manufacturing cost of bipolar plates. Cylindrical fuel cells, on the other hand, not only possess the advantages of traditional fuel cells—cleanliness, environmental friendliness, and fast start-up—but also have advantages such as small size, compact structure, low mass transfer resistance, and high performance. In practical applications, 40%–60% of the chemical energy of the fuel is converted into electrical energy, with the remaining energy mostly converted into heat. If heat cannot be dissipated in time, the system temperature will continue to rise, leading to localized overheating within a single cell or a localized area within the fuel stack, severely affecting the normal operation of the fuel cell. When the proton exchange membrane temperature reaches above 80°C, its thermal stability and proton conductivity will decrease, and in severe cases, membrane dehydration will occur, resulting in a sharp drop in conductivity. When the proton exchange membrane temperature exceeds 130°C, irreversible damage to the membrane will occur, and localized hot spots will lead to membrane perforation, ultimately affecting the safety of battery operation. At the same time, excessively high battery temperatures can also accelerate catalyst degradation.

[0003] Current research on thermal management of tubular fuel cells (CN201810783277.4) cannot utilize structures such as built-in cooling water channels and air-cooled fins due to their compact structure. Therefore, this invention proposes a fuel cell thermal management component based on a rollable heat spreader and its application. By utilizing the flexibility and good temperature uniformity of the rollable heat spreader, the internal temperature distribution of the battery is optimized to achieve good thermal management of the fuel cell stack. Summary of the Invention

[0004] The purpose of this invention is to provide a fuel cell thermal management component based on a rollable heat spreader plate. This component utilizes the heat spreader plate's temperature uniformity characteristics to effectively manage the fuel cell's thermal properties. The fuel cell structure of this component is a columnar hierarchical structure. Holes and slots are provided in the fuel cell's metal current collector casing, into which the rollable heat spreader plate is inserted. The heat spreader plate is divided into a temperature uniformity section in contact with the current collector casing and a temperature control section exposed to the fuel cell. This ensures that the fuel cell operates within its optimal operating temperature range, preventing damage from excessively high local or overall battery temperatures, and avoiding excessively low temperatures that could affect battery startup and reduce performance.

[0005] The present invention is achieved by at least one of the following technical solutions.

[0006] A thermal management component for a fuel cell based on a rollable heat spreader includes a fuel cell, an external temperature control module, and a temperature detection module. The fuel cell contains one or more rollable heat spreaders that can be bent from 0° to 360°. The temperature of the rollable heat spreaders is controlled by the external temperature control module and the temperature detection module.

[0007] Furthermore, the fuel cell includes a metal current collector housing, on which a heat spreader slot is provided, and the rollable heat spreader is located within the heat spreader slot.

[0008] Furthermore, a portion of the rollable heat spreader is exposed outside the metal manifold housing as a temperature control section. The temperature control section encloses a water-cooling block, which has a water-cooling block inlet and a water-cooling block outlet. The external temperature control module controls the water temperature and flow rate flowing through the water-cooling block, thereby performing non-direct contact heating or heat dissipation on the temperature control section of the rollable heat spreader.

[0009] Furthermore, the rollable heat spreader uses polymer material as the outer shell material and uses strip or mesh structure formed by processing polymer material as the support and air passage.

[0010] Furthermore, the rollable temperature equalizer uses a polymer material as the liquid absorbent core and a mixture of one or more of water, ethanol, and acetone as the working fluid.

[0011] Furthermore, the rollable heat spreader is processed with a perforated structure that matches the heat spreader's slots.

[0012] Furthermore, the thickness of the rollable heat spreader is 0.5–2 mm.

[0013] Furthermore, the temperature control section of the rollable heat spreader exposed to the fuel cell accounts for 10% to 30% of the total rollable heat spreader, and the surface of the heat spreader inserted into the fuel cell cavity has a functional layer of thermally conductive grease and thermally conductive silicone to reduce thermal resistance.

[0014] Furthermore, the external temperature control module employs multiple temperature control methods, including electric heating, liquid cooling, and air cooling.

[0015] Furthermore, the temperature detection modules are evenly distributed in a matrix on the current collectors of the cathode and anode inside the columnar fuel cell.

[0016] The fabrication and operation method of the fuel cell thermal management component based on the rollable heat spreader plate includes the following steps: The rollable polymer heat spreader plate is manufactured by sealing the polymer support and the liquid wicking core in the polymer shell through hot pressing or other sealing technologies. The operation step involves utilizing the temperature uniformity characteristics of the rollable heat spreader plate inserted into the slots of the fuel cell current collector shell to improve the temperature uniformity inside the fuel cell. A temperature detection module monitors the internal temperature of the battery in real time, and an external temperature control module is used to heat or cool the exposed temperature control section of the heat spreader plate as needed to keep the battery at its optimal operating temperature and improve battery performance.

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0018] (1) The present invention uses a rollable heat exchange plate with good temperature uniformity to perform thermal management of fuel cells. The fuel cells do not need to be equipped with cooling water channels, optimize battery thermal management and simplify battery structure. The battery temperature can be controlled by an external temperature control module to prevent local temperature from being too high in the stack and to achieve rapid cold start of the stack. The thermal management of the stack is optimized to improve the performance of the stack.

[0019] (2) By setting holes and slots on the current collector shell of the fuel cell and inserting a rollable, thin, highly flexible and insulating flexible polymer heat spreader, the present invention can reduce the weight of the battery, increase the contact area between the heat spreader and the current collector shell, enhance the safety of the battery and achieve a better thermal management effect. Attached Figure Description

[0020] Figure 1 This is a structural diagram of the rollable heat equalizer provided by the present invention;

[0021] Figure 2 A structural diagram of a columnar fuel cell provided by the present invention;

[0022] Figure 3 A schematic diagram showing the combination of the 360° curled heat spreader, the metal current collector housing, and the external temperature control module provided by the present invention.

[0023] Figure 4 A schematic diagram showing the combination of the 180° curled heat spreader, the metal current collector housing, and the external temperature control module provided by the present invention.

[0024] In the figure, 1-aluminum-plastic membrane shell, 2-polyamide strip support, 3-nylon mesh, 4-fuel chamber, 5-cylindrical membrane electrode, 6-cylindrical cathode current collector, 7-metal current collector shell, 8-temperature distribution plate slot, 9-360° bent temperature distribution plate, 10-cylindrical water cooling block, 11-water cooling block inlet, 12-water cooling block outlet, 13-180° bent temperature distribution plate. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Example 1

[0027] This embodiment of the fuel cell thermal management component based on a rollable heat spreader includes a rollable heat spreader, a fuel cell, an external temperature control module, and a temperature detection module. The component works by utilizing the heat spreader's uniform temperature characteristics, which is rolled up and inserted into the slots of the current collector casing, to prevent damage from localized overheating points within the fuel cell. It can also regulate the temperature of the fuel cell stack by heating or cooling the exposed temperature control section based on the real-time temperature distribution inside the cell, thus achieving excellent thermal management of the cylindrical fuel cell. This embodiment uses a single 360° rollable heat spreader 9 for thermal management of the cylindrical fuel cell.

[0028] The rollable heat spreader is manufactured by sealing the polymer support and liquid absorber core within the polymer shell using hot pressing or other sealing techniques. The working steps involve utilizing the heat spreader's temperature uniformity, inserted into the grooves of the fuel cell's current collector casing, to improve the internal temperature uniformity of the fuel cell. A temperature detection module monitors the internal temperature of the battery in real time, and an external temperature control module heats or cools the exposed temperature control section of the heat spreader as needed to maintain the battery at its optimal operating temperature and improve battery performance.

[0029] In this embodiment, as Figure 1 As shown, the 360° bending heat spreader 9 is based on a flexible polymer heat spreader, using an aluminum-plastic film as the shell 1, a polyamide strip support 2 as the air channel, and a nylon mesh 3 with a hydrophilic surface treatment via a sol-gel method as the liquid absorbent core. Deionized water is used as the liquid working fluid. The nylon mesh liquid absorbent core 3 is arranged in groups of three, each in contact with one of the shells 1 on each side. The polyamide strip support 2 is wrapped between the two groups of liquid absorbent cores. The shell 1 is sealed by hot pressing to form a closed cavity. After leak testing, the liquid working fluid is injected into the cavity, and the process involves vacuuming and secondary sealing to complete the process. The integral polymer material gives the heat spreader high flexibility, allowing it to function normally even under large-angle bending.

[0030] like Figure 2 As shown, the fuel cell is a cylindrical fuel cell, and its structure includes a metal current collector shell 7, on which temperature distribution plate slots 8 are machined, and a cylindrical membrane electrode 5 and a cylindrical cathode current collector 6 are wrapped in the middle of the metal current collector shell 7. A fuel chamber 4 is wrapped inside the cylindrical cathode current collector 6.

[0031] like Figure 3 As shown, a 360° rolled-up heat spreader 9 is inserted into the heat spreader slot 8. A portion of the heat spreader 9 is exposed outside the metal manifold housing 7 as a temperature control section. The temperature control section encloses a cylindrical water-cooled block 10. The water-cooled block 10 has a water-cooled block inlet 11 and a water-cooled block outlet 12. The external temperature control module includes a water pump. By controlling the water pump and the heating block or heating rod to heat the water, the water temperature and flow rate flowing through the cylindrical water-cooled block 10 are controlled to perform non-direct contact heating or heat dissipation on the temperature control section of the heat spreader 9.

[0032] In a preferred embodiment, the thickness of the 360° bending heat spreader 9 is 1.5 mm, and the exposed temperature control section of the heat spreader 9 accounts for 20% of the total area of ​​the heat spreader; the surface of the heat spreader inserted into the columnar fuel cell slot has a functional layer of thermally conductive grease and thermally conductive silicone to reduce thermal resistance.

[0033] The columnar fuel cell has uniformly distributed circular holes in each layer to allow fuel to pass through, and the rollable heat spreader is processed with perforated structures that are adapted to the grooves in the fuel cell.

[0034] The cylindrical water-cooling block 10 is a ring-shaped aluminum water-cooling block.

[0035] In this embodiment, the temperature detection module uses K-type thermocouples and is evenly distributed in a matrix on the cylindrical cathode current collector 6 inside the battery and on the inner surface of the metal current collector shell 7. It is connected to a temperature data acquisition card, which is connected to a computer to transmit the collected data to the computer.

[0036] The working method and working principle of this embodiment are described as follows:

[0037] During normal operation of the fuel cell, the heat spreader plate 9, inserted into the slot 8 of the metal current collector casing 7 and bent 360°, utilizes its temperature-spreading characteristics to ensure uniform temperature distribution within the battery and prevent localized high-temperature spots. Simultaneously, a temperature detection module monitors the temperature of various parts of the battery in real time. When the average internal temperature is detected to be too high, the external temperature control module lowers the water temperature flowing into the cylindrical water-cooled block 10 from the inlet 11 and out of the outlet 12, and increases the flow rate. This lowers the temperature of the temperature control section of the heat spreader plate 9, and further reduces the average internal temperature of the battery by ensuring the uniformity of the temperature spreader and control section through the bending of the 360° heat spreader plate 9. Conversely, when the average internal temperature is detected to be too low, the external temperature control module raises the water temperature flowing into the water-cooled block 10 and increases the flow rate to raise the temperature of the control section. This utilizes the temperature spreader plate's uniformity to evenly increase the internal temperature of the battery. The real-time monitoring of the battery's internal temperature by the temperature detection module and the dynamic thermal management by the external temperature control module enable continuous thermal management of the battery.

[0038] The above process maintains the temperature of each part of the hydrogen fuel cell stack within the optimal range, prevents excessive local temperature in the stack, enables rapid cold start of the stack, and optimizes the thermal management of the stack to improve its performance.

[0039] Example 2

[0040] In this embodiment, the fuel cell thermal management component based on a rollable heat spreader includes a rollable heat spreader, a cylindrical fuel cell, an external temperature control module, and a temperature detection module. This embodiment uses a combination of two 180° bent heat spreaders 13 for thermal management of the cylindrical fuel cell.

[0041] The rollable heat spreader used in fuel cells uses polymer materials such as aluminum-plastic film, PDMS, and polyamide film as shell materials, and uses strip-shaped or mesh-like structures formed by processing polymer materials such as polyamide, PDMS, and high nylon as supports and air passages. It uses polymer materials such as nylon mesh and nylon braided tape as liquid absorbent cores, and uses one or more mixtures of liquids such as water, ethanol, and acetone as working fluid.

[0042] In this embodiment, as Figure 1 As shown, the 180° curved heat spreader 13 is based on a flexible polymer heat spreader, with an aluminum-plastic film as the shell 1, a polyamide strip support 2 as the air channel, a nylon mesh 3 with a surface hydrophilic treatment by sol-gel method as the liquid absorbent core, and deionized water as the liquid working fluid.

[0043] In one embodiment, the nylon mesh absorbent core 3 is arranged in three layers, each in contact with one of the two shells 1. A polyamide strip support 2 is wrapped between the two sets of absorbent cores 3. The shell 1 is sealed by heat pressing to form a closed cavity. After leak testing, liquid working fluid is injected into the cavity, and the cavity is then vacuumed and sealed a second time. The integral polymer material gives the heat spreader high flexibility, allowing it to function normally even under large-angle bending.

[0044] In a preferred embodiment, the thickness of the 180° bent heat spreader 13 is 1.0 mm, and the exposed temperature control section of the heat spreader accounts for 30% of the total area of ​​the heat spreader. The surface of the heat spreader inserted into the cavity of the columnar fuel cell has a functional layer of thermally conductive silicone grease and thermally conductive silicone to reduce thermal resistance. The columnar fuel cell typically has uniformly distributed circular hole structures for fuel to pass through in each layer structure, and the rollable heat spreader is processed with a perforated structure adapted to the cavity of the fuel cell.

[0045] In this embodiment, as Figure 2As shown, the columnar fuel cell is a cylindrical fuel cell with a structure including a metal current collector shell 7, on which temperature distribution plate slots 8 are machined, and a cylindrical membrane electrode 5 and a cylindrical cathode current collector 6 are wrapped in the middle of the metal current collector shell 7. A fuel chamber 4 is wrapped inside the cylindrical cathode current collector 6.

[0046] In this embodiment, as Figure 4 As shown, the metal manifold housing 7 has a heat spreader slot 8, into which two 180° bent heat spreaders 13 are inserted. A portion of the heat spreader 13 is exposed outside the metal manifold housing 7 as a temperature control section. The temperature control section encloses a cylindrical water-cooled block 10. The cylindrical water-cooled block 10 has a water-cooled block inlet 11 and a water-cooled block outlet 12. The external temperature control module uses a computer to control the flow rate of the water pump and to control the heating block or heating rod to heat the water. This controls the water temperature and flow rate through the cylindrical water-cooled block 10, thereby performing non-direct contact heating or heat dissipation on the temperature control section of the heat spreader 13.

[0047] The cylindrical water-cooling block 10 is a ring-shaped aluminum water-cooling block.

[0048] In this embodiment, the temperature detection module uses K-type thermocouples evenly distributed in a matrix on the cylindrical cathode current collector 6 inside the battery and on the inner surface of the metal current collector casing 7, and is connected to a temperature data acquisition card. The temperature data acquisition card is connected to a computer to transmit the acquired data to the computer.

[0049] The working method and working principle of this embodiment are described as follows:

[0050] During normal operation of the fuel cell, the two 180° bent heat spreaders 13, inserted into the heat spreader slots 8 machined into the metal current collector casing 7, utilize their heat spreader characteristics to ensure uniform temperature distribution within the battery and prevent localized high-temperature spots. Simultaneously, a temperature detection module monitors the temperature of various parts of the battery in real time. When the average internal temperature is detected to be too high, the external temperature control module lowers the water temperature flowing into the cylindrical water-cooled block 10 from the water-cooled block inlet 11 and out of the water-cooled block outlet 12, and increases the flow rate. This lowers the temperature of the heat spreader control section, and through the heat spreader and control section of the two 180° bent heat spreaders 13, the average internal temperature of the battery is uniformly reduced. When the average internal temperature is detected to be too low, the external temperature control module controls the increase of the water temperature flowing into the water-cooled block 10 and the increase of the flow rate to raise the temperature of the control section. Utilizing the heat spreader's heat spreader properties, the internal temperature of the battery is uniformly increased. Through real-time monitoring of the internal temperature by the temperature detection module, the external temperature control module continuously performs dynamic thermal management of the battery.

[0051] The above process maintains the temperature of each part of the hydrogen fuel cell stack within the optimal range, prevents excessive local temperature in the stack, enables rapid cold start of the stack, and optimizes the thermal management of the stack to improve its performance.

[0052] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations within the meaning and scope of the equivalents of the claims are intended to be embraced within the invention, and no drawings in the claims should be construed as limiting the scope of the claims.

[0053] This invention is not limited to the above description of the embodiments. Any improvements and modifications made by those skilled in the art based on the disclosure of the invention without creative effort, such as the type of columnar fuel cell, the specific selection of the temperature sensing module device, and the selection of the external temperature control module device, should be within the protection scope of this invention.

Claims

1. A thermal management component for a fuel cell based on a rollable heat spreader, characterized in that: The system includes a fuel cell, an external temperature control module, and a temperature detection module. The fuel cell is a cylindrical fuel cell and includes a metal current collector housing with temperature distribution plate slots. Inside the fuel cell are one or more flexible temperature distribution plates bent from 0° to 360°. These flexible temperature distribution plates are located within the temperature distribution plate slots; the portion within the slots is the temperature distribution section, and the portion exposed outside the metal current collector housing is the temperature control section. The temperature control section encloses a water-cooled block, which has a water-cooled block inlet and an outlet. The external temperature control module controls the water temperature and flow rate through the water-cooled block to provide non-direct contact heating or cooling to the temperature control section of the flexible temperature distribution plate. The temperature detection modules are evenly distributed in a matrix on the current collectors of the cathode and anode inside the cylindrical fuel cell. The temperature of the flexible temperature distribution plate is detected and controlled by the external temperature control module and the temperature detection module.

2. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The rollable heat spreader uses polymer material as the outer shell material and uses strip or mesh structure formed by processing polymer material as the support and air passage.

3. The fuel cell thermal management component based on a rollable heat spreader according to claim 2, characterized in that: The rollable heat spreader uses a polymer material as the liquid absorber and a mixture of one or more of water, ethanol, and acetone as the working fluid.

4. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The rollable heat spreader is processed with a perforated structure that matches the grooves of the heat spreader.

5. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The thickness of the rollable heat spreader is 0.5–2 mm.

6. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The temperature control section accounts for 10% to 30% of the entire rollable heat spreader plate. The surface of the heat spreader section inserted into the groove of the heat spreader plate is provided with a functional layer of thermally conductive grease and thermally conductive silicone to reduce thermal resistance.

7. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The external temperature control module employs multiple temperature control methods, including electric heating, liquid cooling, and air cooling.

8. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 1, characterized in that: The columnar fuel cell is a cylindrical fuel cell, and its structure includes the metal current collector shell, in which a cylindrical membrane electrode and a cylindrical cathode current collector are wrapped, and a fuel chamber is wrapped inside the cylindrical cathode current collector.

9. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 8, characterized in that: The temperature detection module uses a K-type thermocouple and is connected to a temperature data acquisition card, which is connected to a computer.

10. The fuel cell thermal management assembly based on a rollable heat spreader according to claim 8, characterized in that: The water-cooled block is a cylindrical water-cooled block, and the cylindrical water-cooled block is a ring-shaped aluminum water-cooled block.

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