WO2018214098A1 - 燃料电池的阴极结构 - Google Patents

燃料电池的阴极结构 Download PDF

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WO2018214098A1
WO2018214098A1 PCT/CN2017/085899 CN2017085899W WO2018214098A1 WO 2018214098 A1 WO2018214098 A1 WO 2018214098A1 CN 2017085899 W CN2017085899 W CN 2017085899W WO 2018214098 A1 WO2018214098 A1 WO 2018214098A1
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cathode
fuel cell
gas permeability
cooling fluid
flow
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PCT/CN2017/085899
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English (en)
French (fr)
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科施恩·阿瑟
顾志军
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江苏清能新能源技术股份有限公司
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Priority to US16/761,002 priority Critical patent/US20210210767A1/en
Priority to PCT/CN2017/085899 priority patent/WO2018214098A1/zh
Priority to CN201780034756.XA priority patent/CN109643810A/zh
Publication of WO2018214098A1 publication Critical patent/WO2018214098A1/zh

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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
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/96—Carbon-based electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/8605—Porous electrodes
    • H01M4/861—Porous electrodes with a gradient in the porosity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/8647—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites
    • H01M4/8657—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites layered
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8803—Supports for the deposition of the catalytic active composition
    • H01M4/8807—Gas diffusion layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8825—Methods for deposition of the catalytic active composition
    • H01M4/886—Powder spraying, e.g. wet or dry powder spraying, plasma spraying
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/9008—Organic or organo-metallic compounds
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/9075—Catalytic material supported on carriers, e.g. powder carriers
    • H01M4/9083—Catalytic material supported on carriers, e.g. powder carriers on carbon or graphite
    • 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
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M2004/8678—Inert electrodes with catalytic activity, e.g. for fuel cells characterised by the polarity
    • H01M2004/8689—Positive electrodes
    • 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

Definitions

  • the present invention relates to a cathode structure of a fuel cell.
  • the fuel cell can directly convert hydrogen into electric energy with high efficiency, and the reaction by-product is pure water, so it has the advantages of energy saving and environmental protection.
  • the main structure of a fuel cell can generally be divided into three types: a cathode open air cooling type, a cathode closed air cooling type, and a cathode closed liquid cooling type.
  • the area near the air inlet is often lower in temperature, which is prone to water accumulation and affects performance; the area near the air outlet is often hot and prone to dehydration. And affect performance. This problem is particularly noticeable in cold or cold seasons.
  • the coolant circulation pump is often required to operate at a high speed, and the power consumption is too large.
  • a region close to the inlet of the oxygen-supplying air stream tends to cause dehydration problems due to moisture absorption of the oxygen-supplying air stream, thereby affecting performance.
  • the technical problem to be solved by the present invention is to provide a cathode structure of a fuel cell in order to overcome the defects of water accumulation or dehydration caused by the difference in temperature and humidity inside the cathode structure of the fuel cell in the prior art.
  • the invention provides a cathode structure of a fuel cell, which comprises a cathode diffusion layer, the cathode An air permeability adjusting structure is disposed around the diffusion layer, and the cathode gas permeability of the air permeability adjusting structure is gradually changed in the fluid flow direction.
  • the cathode gas permeability of the gas permeability adjusting structure is gradually reduced from the cooling fluid inlet to the cooling fluid outlet.
  • the cathode gas permeability of the gas permeability adjusting structure is gradually increased from the oxygen supply flow inlet to the oxygen supply flow outlet.
  • the air permeability adjusting structure is a mesh with a venting hole, and the mesh is disposed between the cathode flow channel plate and the cathode diffusion layer.
  • the cathode gas permeability of the mesh is gradually reduced from the cooling fluid inlet to the cooling fluid outlet.
  • the direction of the mesh from the cooling fluid inlet to the cooling fluid outlet is divided into three regions, respectively a high venting zone, a medium venting zone and a low venting zone, the high venting zone, the middle venting zone and the low zone
  • the diameter of the vent hole of the permeable area is gradually reduced.
  • the cathode diffusion layer is carbon paper, and one side of the carbon paper facing the membrane electrode assembly is a sprayed layer, and the cathode filling layer has a mixture of carbon powder and PTFE powder, and the cathode filling layer is The gas permeability adjustment structure is described.
  • the cathode gas permeability of the cathode filling layer gradually decreases from the cooling fluid inlet to the cooling fluid outlet.
  • the direction of the cathode filling layer from the cooling fluid inlet to the cooling fluid outlet is divided into three regions, a low density region, a medium density region and a high density region, respectively, the low density region and the medium density region.
  • the spray density in the high density zone is gradually increased.
  • a side of the cathode flow channel plate facing the cathode diffusion layer is provided with a flow channel layer having a plurality of flow channels from the oxygen supply flow inlet to the oxygen supply flow outlet, two adjacent A back is formed between the flow passages, and the flow passage layer is the gas permeability adjusting structure.
  • the cathode gas permeability of the flow channel layer is gradually increased from the oxygen supply flow inlet to the oxygen supply flow outlet.
  • the flow channel layer is divided into three regions from a direction for supplying oxygen to the outlet for supplying oxygen, respectively, a wide back region, a middle back region and a narrow back region, the wide back region and the middle back
  • the ratio of the flow path of the zone and the narrow back region to the width of the back is gradually increased.
  • the cathode structure of the fuel cell is provided with a gas permeability adjusting structure having a cathode gas permeability change around the cathode diffusion layer, and skillfully compensates for the difference caused by the difference in temperature and humidity, thereby improving the water accumulation in the cathode structure of the fuel cell or The problem of dehydration effectively improves the water management of the fuel cell.
  • Figure 1 is a schematic view showing the structure of a first embodiment of a cathode structure of a fuel cell of the present invention.
  • FIG. 2 is a schematic view showing the structure of a mesh of a cathode structure of the fuel cell shown in FIG. 1.
  • Fig. 3 is a partial enlarged view of a high gas permeable region of the mesh of the cathode structure of the fuel cell shown in Fig. 2.
  • Fig. 4 is a partially enlarged view showing a gas permeable region in a mesh sheet of a cathode structure of the fuel cell shown in Fig. 2.
  • Fig. 5 is a partial enlarged view of a low gas permeable region of a mesh of a cathode structure of the fuel cell shown in Fig. 2.
  • Figure 6 is a schematic view showing the structure of a second embodiment of the cathode structure of the fuel cell of the present invention.
  • Fig. 7 is a structural schematic view showing a sprayed layer of a cathode structure of the fuel cell shown in Fig. 6.
  • Figure 8 is a schematic view showing the structure of a third embodiment of the cathode structure of the fuel cell of the present invention.
  • Fig. 9 is a view showing the structure of a cathode flow path plate and a flow path layer of a cathode structure of the fuel cell shown in Fig. 8.
  • the cathode structure of the fuel cell generally includes a cathode flow channel plate 1, a cathode diffusion layer 2, and a cathode filling layer 3 which are sequentially laid, and the cathode filling layer 3 is bonded to the membrane electrode assembly 4.
  • the invention provides a cathode structure of a fuel cell, which comprises a cathode diffusion layer 2, and a gas permeability adjusting structure is arranged around the cathode diffusion layer 2.
  • the cathode gas permeability of the gas permeability adjusting structure is gradually changed along the fluid flow direction.
  • the cathode gas permeability of the gas permeability adjusting structure When designed for the flow path of the cooling fluid, the cathode gas permeability of the gas permeability adjusting structure is gradually reduced from the cooling fluid inlet to the cooling fluid outlet. When designing the flow path for the oxygen flow, the cathode gas permeability of the gas permeability adjusting structure is gradually increased from the oxygen supply flow inlet to the oxygen supply flow outlet.
  • the present invention intelligently compensates for the difference caused by the difference in temperature and humidity by providing a gas permeability adjusting structure with a change in cathode gas permeability around the cathode diffusion layer 2, thereby improving the problem of water accumulation or dehydration in the cathode structure of the fuel cell, and is effective.
  • the water management of fuel cells has been improved.
  • the fuel cell of the present invention is preferably a proton exchange membrane fuel cell.
  • the cathode structure of the fuel cell of the present invention has three embodiments, as follows.
  • the air permeability adjusting structure is a mesh 5 of the dense venting holes 51.
  • the mesh 5 is disposed between the cathode flow path plate 1 and the cathode diffusion layer 2.
  • the cathode gas permeability of the mesh 5 is gradually lowered from the cooling fluid inlet to the cooling fluid outlet. Specifically, the direction of the web 5 from the cooling fluid inlet to the cooling fluid outlet is divided into three regions, a high venting zone 52, a medium venting zone 53 and a low venting zone 54, a high venting zone 52, and a medium venting zone 53.
  • the diameter of the vent hole 51 of the low venting region 54 is gradually reduced.
  • a front cross-sectional view of the cathode structure of the fuel cell, the anode region under the membrane electrode assembly 4 is not related to the present case, and therefore is not shown, and a known technique can be referred to.
  • the mesh sheet 5 shown in Fig. 2 is placed between the cathode flow channel plate 1 and the cathode diffusion layer 2, and viewed from the front side of Fig. 1, the low venting area 54 of the mesh sheet 5 in the near and far direction in the line of sight direction, Breathable zone 53 and high venting zone 52.
  • the cooling fluid inlet is located at the back of FIG. 1, and the cooling fluid outlet is located at the front surface of FIG. 1.
  • the cooling fluid flows through the region of the cathode runner plate 1 corresponding to the high gas permeable region 52, the region corresponding to the medium gas permeable region 53, and the lower portion.
  • the area corresponding to the permeable area 54 is not related to the present case, and therefore is not shown, and a known technique can be
  • This web 5 is disposed between the cathode diffusion layer 2 and the cathode runner plate 1 of each of the single cells among the fuel cells.
  • the high venting zone 52 corresponds to the cooling fluid inlet. Although the temperature is lower, due to the higher gas permeability, water accumulation is avoided; the low venting zone 54 corresponds to the cooling fluid outlet, although the temperature is higher, but the gas permeability is lower, so avoid Dehydration.
  • vent hole 51 on the center hole of the web 5 are from the L 1mm, high permeability region 51 of the aperture 52 of the holes D 1 is 0.7mm (FIG. 3 shown), the aperture diameter D of permeable region 51 of the holes 53 is 0.59mm 2 (FIG. 4), the low permeability region 51 of the aperture 54 of the holes D 3 is 0.5mm (FIG. 5).
  • This embodiment is preferably applied to a cathode open type fuel cell.
  • the cathode diffusion layer 2 is a carbon paper 6, one side of the carbon paper 6 facing the membrane electrode assembly 4 is a sprayed layer 7, the sprayed layer 7 is sprayed with a mixture of carbon powder and PTFE powder, and the sprayed layer 7 is a gas permeability adjusting structure, and the sprayed layer 7 is The cathode gas permeability is gradually reduced from the cooling fluid inlet to the cooling fluid outlet.
  • the direction from the cooling fluid inlet to the cooling fluid outlet is divided into three regions, namely, a low density region 71, a medium density region 72, and a high density region 73, a low density region 71, and a medium density region 72.
  • the spray density of the high density zone 73 is gradually increased.
  • the carbon paper 6 itself serves as the cathode diffusion layer 2, and the surface thereof is sprayed with a mixture of carbon powder and PTFE powder, and then hot pressed to form a sprayed layer 7, which serves as a gas permeability adjusting structure and functions as a cathode filling layer. 3.
  • the specifications and ratios of the carbon powder and the PTFE powder, and the temperature and pressure of the hot pressing are all referred to well-known techniques. Unlike the known technique, the spray amount and/or the number of spray passes of the mixture of the carbon powder and the PTFE powder are different in different regions, thereby forming the low density region 71, the medium density region 72, and the high density region 73.
  • a front cross-sectional view of the cathode structure of the fuel cell, the anode region under the membrane electrode assembly 4 is not related to the present case, and therefore is not shown, and a known technique can be referred to.
  • the cathode filling layer 3 i.e., the sprayed layer 7
  • the high density zone 73, the medium density zone 72, and the low density zone 71 are sequentially in the near and far directions in the line of sight.
  • the back of Figure 6 is the cooling fluid inlet, the front of Figure 6.
  • the cooling fluid sequentially flows through a region of the cathode runner plate 1 corresponding to the low-density region 71, a region corresponding to the medium-density region 72, and a region corresponding to the high-density region 73.
  • the carbon paper 6 sprayed with the sprayed layer 7 is disposed between the membrane electrode assembly 4 of each unit cell and the cathode runner plate 1 among the fuel cells, and the carbon paper 6 serves as a cathode diffusion layer 2, and a sprayed layer attached to the surface thereof 7 (i.e., the cathode filling layer 3) faces the membrane electrode assembly 4.
  • the low density zone 71 corresponds to the cooling fluid inlet, although the temperature is lower, but the water retention is avoided due to the higher gas permeability;
  • the high density zone 73 corresponds to the cooling fluid outlet, although the temperature is higher, but the gas permeability is lower, so avoid Dehydration.
  • the preferred air permeability of each of the above-mentioned sprayed layers 7 is that the air permeability of the low density region 71 is 0.7 cm 3 /(cm 2 .s), and the air permeability of the medium density region 72 is 0.5 cm 3 /(cm 2 .s).
  • the high-density area 73 has an air permeability of 0.35 cm 3 /(cm 2 .s).
  • This embodiment is preferably applied to a cathode open type fuel cell.
  • FIG. 8 to 9 A third embodiment of the cathode structure of the fuel cell of the present invention is shown in Figs. 8 to 9 .
  • One side of the cathode flow path plate 1 facing the cathode diffusion layer 2 is provided with a flow path layer 8 having a plurality of flow paths 81 from the oxygen supply flow inlet 9 to the oxygen supply flow outlet 10, adjacent to the two flow paths 81.
  • a spine 82 is formed between them, and the flow channel layer 8 is a gas permeability adjusting structure, and the cathode gas permeability of the flow channel layer 8 is gradually increased from the oxygen supply flow inlet 9 to the oxygen supply flow outlet 10.
  • the flow channel layer 8 is divided into three regions from the oxygen supply flow inlet 9 to the oxygen supply flow outlet 10, which are a wide back region 83, a middle back region 84 and a narrow back region 85, a wide back region 83, and a middle back region.
  • the ratio of the flow path 81 of the 84 and the narrow back region 85 to the width of the back 82 is gradually increased.
  • a front cross-sectional view of the cathode structure of the fuel cell, the anode region under the membrane electrode assembly 4 is not related to the present case, and therefore is not shown, and a known technique can be referred to.
  • the oxygen supply flow flows from the left side, passes through the wide back region 83, the middle back region 84, and the narrow back region 85 of the flow channel layer 8, and flows out from the right side.
  • the cathode runner plate 1 and the runner layer 8 of this embodiment have a supply port 9 for the oxygen flow on the left side and an oxygen supply outlet port 10 on the right side.
  • the ratio of the width of the flow passage 81 and the back 82 of the wide back region 83 is low, and the air permeability is low, so that a large amount of dry oxygen supply flowing into the fuel cell is avoided.
  • the problem of dehydration caused by wetness; the ratio of the width of the flow passage 81 and the back 82 of the middle back region 84 is medium, and the air permeability is medium, and the oxygen supply flow reaching the region has already absorbed a small amount in the wide back region 83, and has a certain humidity.
  • the ratio of the width of the flow passage 81 of the narrow back region 85 to the width of the back 82 is relatively high, and the air permeability is high, and the oxygen supply flow to this region is already moist, although the air permeability is high and the moisture absorption is not large.
  • the width of the flow passage 81 and the back 82 of each of the above-mentioned flow channel layers 8 is such that the width of the flow passage 81 of the wide back region 83 is 0.9 mm, and the width of the back 82 of the wide back region 83 is 1.8 mm;
  • the width of the flow path 81 of 84 is 0.9 mm, the width of the back 82 of the middle back region 84 is 1.2 mm;
  • the width of the flow path 81 of the narrow back region 85 is 1.2 mm, and the width of the back 82 of the narrow back region 85 is 0.9 mm.
  • This embodiment is preferably applied to a cathode-enclosed fuel cell.

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Abstract

一种燃料电池的阴极结构，包括阴极扩散层（2），所述阴极扩散层（2）的周围设有透气率调节结构，所述透气率调节结构的阴极透气率沿流体流动方向逐步变化。该燃料电池的阴极结构，通过在阴极扩散层（2）的周围设置阴极透气率变化的透气率调节结构，巧妙地补偿了温度、湿度不同所引起的差异，从而改善了燃料电池的阴极结构内积水或脱水问题，有效地提高了燃料电池的水管理。

Description

燃料电池的阴极结构 技术领域
本发明涉及一种燃料电池的阴极结构。
背景技术
燃料电池，能以较高的效率将氢气直接转化为电能，反应副产品是纯水，因此具有节能、环保等优点。燃料电池的主体结构通常可以分为三种：阴极开放式空气冷却型、阴极封闭式空气冷却型、阴极封闭式液体冷却型。
对于空气冷却型燃料电池，无论是阴极开放式还是阴极封闭式，靠近进风口的区域往往温度较低，容易发生积水问题而影响性能；靠近出风口的区域往往温度较高，容易发生脱水问题而影响性能。在寒冷地区或者寒冷季节，这个问题尤其显著。
对于液体冷却型燃料电池，虽然燃料电池的冷却液进口和冷却液出口温差较小，但是为了使得这一温差进一步减小，往往需要冷却液循环泵高速运行，功耗太大。
另外，对于阴极封闭式燃料电池，无论是空气冷却型还是液体冷却型，靠近供氧空气流进口的区域，往往由于供氧空气流的吸湿，容易发生脱水问题而影响性能。
发明内容
本发明所要解决的技术问题是为了克服现有技术中的燃料电池的阴极结构内部因温度、湿度不同而引起的积水或脱水的缺陷，而提供一种燃料电池的阴极结构。
本发明通过以下技术方案解决上述技术问题：
本发明提供了一种燃料电池的阴极结构，它包括阴极扩散层，所述阴极 扩散层的周围设有透气率调节结构，所述透气率调节结构的阴极透气率沿流体流动方向逐步变化。
较佳地，所述透气率调节结构的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
较佳地，所述透气率调节结构的阴极透气率从供氧气流进口至供氧气流出口逐步增大。
较佳地，所述透气率调节结构为密布透气孔的网片，所述网片设置于阴极流道板与所述阴极扩散层之间。
较佳地，所述网片的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
较佳地，所述网片从冷却流体进口至冷却流体出口的方向被分为三个区域，分别为高透气区、中透气区和低透气区，所述高透气区、中透气区和低透气区的透气孔的孔径逐步变小。
较佳地，所述阴极扩散层为碳纸，所述碳纸面向膜电极组件的一面为喷涂层，所述阴极填平层有碳粉与PTFE粉的混合物，所述阴极填平层为所述透气率调节结构。
较佳地，所述阴极填平层的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
较佳地，所述阴极填平层从冷却流体进口至冷却流体出口的方向被分为三个区域，分别为低密度区、中密度区和高密度区，所述低密度区、中密度区和高密度区的喷涂密度逐步变大。
较佳地，阴极流道板面向所述阴极扩散层的一面设置有流道层，所述流道层具有多条从供氧气流进口至供氧气流出口的流道，相邻两个所述流道之间形成脊背，所述流道层为所述透气率调节结构。
较佳地，所述流道层的阴极透气率从供氧气流进口至供氧气流出口逐步增大。
较佳地，所述流道层从供氧气流进口至供氧气流出口的方向被分为三个区域，分别为宽脊背区、中脊背区和窄脊背区，所述宽脊背区、中脊背区和窄脊背区的流道与脊背的宽度的比值逐步变大。
在符合本领域常识的基础上，上述各优选条件，可任意组合，即得本发明各较佳实例。
本发明的积极进步效果在于：
该燃料电池的阴极结构，通过在阴极扩散层的周围设置阴极透气率变化的透气率调节结构，巧妙地补偿了温度、湿度不同所引起的差异，从而改善了燃料电池的阴极结构内积水或脱水问题，有效地提高了燃料电池的水管理。
附图说明
图1为本发明燃料电池的阴极结构的第一种实施例的结构示意图。
图2为图1所示的燃料电池的阴极结构的网片的结构示意图。
图3为图2所示的燃料电池的阴极结构的网片的高透气区的局部放大图。
图4为图2所示的燃料电池的阴极结构的网片的中透气区的局部放大图。
图5为图2所示的燃料电池的阴极结构的网片的低透气区的局部放大图。
图6为本发明燃料电池的阴极结构的第二种实施例的结构示意图。
图7为图6所示的燃料电池的阴极结构的喷涂层的结构示意图。
图8为本发明燃料电池的阴极结构的第三种实施例的结构示意图。
图9为图8所示的燃料电池的阴极结构的阴极流道板、流道层的结构示意图。
附图标记说明
阴极流道板1
阴极扩散层2
阴极填平层3
膜电极组件4
网片5
透气孔51
高透气区52
中透气区53
低透气区54
碳纸6
喷涂层7
低密度区71
中密度区72
高密度区73
流道层8
流道81
脊背82
宽脊背区83
中脊背区84
窄脊背区85
供氧气流进口9
供氧气流出口10
具体实施方式
下面通过实施例的方式进一步说明本发明，但并不因此将本发明限制在 所述的实施例范围之中。
燃料电池的阴极结构通常包括依次铺设的阴极流道板1、阴极扩散层2、阴极填平层3，阴极填平层3与膜电极组件4相贴合。本发明提供一种燃料电池的阴极结构，它包括阴极扩散层2，阴极扩散层2的周围设有透气率调节结构，透气率调节结构的阴极透气率沿流体流动方向逐步变化。
针对冷却流体的流动路径设计时，透气率调节结构的阴极透气率从冷却流体进口至冷却流体出口逐步降低。针对供氧气流的流动路径设计时，透气率调节结构的阴极透气率从供氧气流进口至供氧气流出口逐步增大。
本发明通过在阴极扩散层2的周围设置阴极透气率变化的透气率调节结构，巧妙地补偿了温度、湿度不同所引起的差异，从而改善了燃料电池的阴极结构内积水或脱水问题，有效地提高了燃料电池的水管理。
本发明所述的燃料电池，优选为质子交换膜燃料电池。
本发明燃料电池的阴极结构，具有三个实施例，具体如下。
如图1至图5所示为本发明燃料电池的阴极结构的第一个实施例。透气率调节结构为密布透气孔51的网片5，网片5设置于阴极流道板1与阴极扩散层2之间，网片5的阴极透气率从冷却流体进口至冷却流体出口逐步降低。具体而言，网片5从冷却流体进口至冷却流体出口的方向被分为三个区域，分别为高透气区52、中透气区53和低透气区54，高透气区52、中透气区53和低透气区54的透气孔51的孔径逐步变小。
如图1所示为此燃料电池的阴极结构的正视截面图，膜电极组件4下方的阳极区域与本案无关，因此没有画出，可参照公知技术。图2所示的网片5平放在阴极流道板1与阴极扩散层2之间，从图1的正面看，沿视线方向由近及远依次为网片5的低透气区54、中透气区53和高透气区52。冷却流体进口位于图1的背面，冷却流体出口位于图1的正面，冷却流体依次流过阴极流道板1与高透气区52相对应的区域、与中透气区53相对应的区域、与低透气区54相对应的区域。
此网片5被安置于燃料电池之中的每个单电池的阴极扩散层2与阴极流道板1之间。高透气区52对应冷却流体进口，虽然温度较低，但是由于透气率较高，所以避免了积水；低透气区54对应冷却流体出口，虽然温度较高，但是由于透气率较低，所以避免了脱水。
上述网片5的透气孔51较优选的孔径为：网片5上的透气孔51的孔心距L均为1mm，高透气区52的透气孔51的孔径D1为0.7mm(如图3所示)，中透气区53的透气孔51的孔径D2为0.59mm(如图4所示)，低透气区54的透气孔51的孔径D3为0.5mm(如图5所示)。
该实施例优选应用于阴极开放式燃料电池中。
如图6至图7所示为本发明燃料电池的阴极结构的第二个实施例。阴极扩散层2为碳纸6，碳纸6面向膜电极组件4的一面为喷涂层7，喷涂层7喷涂有碳粉与PTFE粉的混合物，喷涂层7为透气率调节结构，喷涂层7的阴极透气率从冷却流体进口至冷却流体出口逐步降低。具体而言，喷涂层7从冷却流体进口至冷却流体出口的方向被分为三个区域，分别为低密度区71、中密度区72和高密度区73，低密度区71、中密度区72和高密度区73的喷涂密度逐步变大。
碳纸6本身作为阴极扩散层2，其表面喷涂了碳粉与PTFE粉的混合物后再热压形成喷涂层7，该喷涂层7即起到透气率调节结构的作用又充当了阴极填平层3。碳粉与PTFE粉的规格、配比，热压的温度、压力，均参照公知技术。与公知技术不同的是，在不同的区域，碳粉与PTFE粉的混合物的喷涂量和/或喷涂遍数不同，从而形成了低密度区71、中密度区72和高密度区73。
如图6所示为此燃料电池的阴极结构的正视截面图，膜电极组件4下方的阳极区域与本案无关，因此没有画出，可参照公知技术。从图6的正面看，在此阴极填平层3(即喷涂层7)中，沿视线方向由近及远依次为高密度区73、中密度区72、低密度区71。图6的背面为冷却流体进口，图6的正面 为冷却流体出口，冷却流体依次流过阴极流道板1与低密度区71相对应的区域、与中密度区72相对应的区域、与高密度区73相对应的区域。
喷涂有喷涂层7的碳纸6被安置于燃料电池之中每个单电池的膜电极组件4与阴极流道板1之间，碳纸6充当阴极扩散层2，附着于其表面的喷涂层7(即阴极填平层3)面向膜电极组件4。低密度区71对应冷却流体进口，虽然温度较低，但是由于透气率较高，所以避免了积水；高密度区73对应冷却流体出口，虽然温度较高，但是由于透气率较低，所以避免了脱水。
上述喷涂层7的各个区域优选的透气率为：低密度区71的透气率达0.7cm3/(cm2.s)，中密度区72的透气率达0.5cm3/(cm2.s)，高密度区73的透气率达0.35cm3/(cm2.s)。
该实施例优选应用于阴极开放式燃料电池中。
如图8至图9所示为本发明燃料电池的阴极结构的第三个实施例。阴极流道板1面向阴极扩散层2的一面设置有流道层8，流道层8具有多条从供氧气流进口9至供氧气流出口10的流道81，相邻两个流道81之间形成脊背82，流道层8为透气率调节结构，流道层8的阴极透气率从供氧气流进口9至供氧气流出口10逐步增大。流道层8从供氧气流进口9至供氧气流出口10的方向被分为三个区域，分别为宽脊背区83、中脊背区84和窄脊背区85，宽脊背区83、中脊背区84和窄脊背区85的流道81与脊背82的宽度的比值逐步变大。
如图8所示为此燃料电池的阴极结构的正视截面图，膜电极组件4下方的阳极区域与本案无关，因此没有画出，可参照公知技术。供氧气流由左侧流入，依次经过流道层8的宽脊背区83、中脊背区84、窄脊背区85，由右侧流出。
如图9所示为该实施例的阴极流道板1和流道层8，其左侧为供氧气流进口9，右侧为供氧气流出口10。宽脊背区83的流道81和脊背82的宽度的比值较低，透气率较低，避免了刚进入燃料电池的干燥的供氧气流大量吸 湿而导致脱水的问题；中脊背区84的流道81和脊背82的宽度的比值中等，透气率中等，到达此区域的供氧气流已经在宽脊背区83少量吸湿，已有一定的湿度而不至于大量吸湿；窄脊背区85的流道81与脊背82的宽度的比值比较高，透气率较高，到达此区域的供氧气流已经较为潮湿，虽然透气率较高也不至于大量吸湿。
上述流道层8的各个区域优选的流道81、脊背82的宽度为：宽脊背区83的流道81的宽度为0.9mm，宽脊背区83的脊背82的宽度为1.8mm；中脊背区84的流道81的宽度为0.9mm，中脊背区84的脊背82的宽度为1.2mm；窄脊背区85的流道81的宽度为1.2mm，窄脊背区85的脊背82的宽度为0.9mm。
该实施例优选应用于阴极封闭式燃料电池中。
本发明不局限于上述实施方式，不论在其形状或结构上作任何变化，均落在本发明的保护范围之内。本发明的保护范围是由所附权利要求书限定的，本领域的技术人员在不背离本发明的原理和实质的前提下，可以对这些实施方式做出多种变更或修改，但这些变更和修改均落入本发明的保护范围。

Claims (12)

  1. 一种燃料电池的阴极结构，其特征在于：它包括阴极扩散层(2)，所述阴极扩散层(2)的周围设有透气率调节结构，所述透气率调节结构的阴极透气率沿流体流动方向逐步变化。
  2. 如权利要求1所述的燃料电池的阴极结构，其特征在于：所述透气率调节结构的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
  3. 如权利要求1所述的燃料电池的阴极结构，其特征在于：所述透气率调节结构的阴极透气率从供氧气流进口至供氧气流出口逐步增大。
  4. 如权利要求1所述的燃料电池的阴极结构，其特征在于：所述透气率调节结构为密布透气孔(51)的网片(5)，所述网片(5)设置于阴极流道板(1)与所述阴极扩散层(2)之间。
  5. 如权利要求4所述的燃料电池的阴极结构，其特征在于：所述网片(5)的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
  6. 如权利要求4所述的燃料电池的阴极结构，其特征在于：所述网片(5)从冷却流体进口至冷却流体出口的方向被分为三个区域，分别为高透气区(52)、中透气区(53)和低透气区(54)，所述高透气区(52)、中透气区(53)和低透气区(54)的透气孔(51)的孔径逐步变小。
  7. 如权利要求1所述的燃料电池的阴极结构，其特征在于：所述阴极扩散层(2)为碳纸(6)，所述碳纸(6)面向膜电极组件(4)的一面为阴极填平层(3)，所述阴极填平层(3)有碳粉与PTFE粉的混合物，所述阴极填平层(3)为所述透气率调节结构。
  8. 如权利要求7所述的燃料电池的阴极结构，其特征在于：所述阴极填平层(3)的阴极透气率从冷却流体进口至冷却流体出口逐步降低。
  9. 如权利要求7所述的燃料电池的阴极结构，其特征在于：所述阴极填平层(3)从冷却流体进口至冷却流体出口的方向被分为三个区域，分别 为低密度区(71)、中密度区(72)和高密度区(73)，所述低密度区(71)、中密度区(72)和高密度区(73)的喷涂密度逐步变大。
  10. 如权利要求1所述的燃料电池的阴极结构，其特征在于：阴极流道板(1)面向所述阴极扩散层(2)的一面设置有流道层(8)，所述流道层(8)具有多条从供氧气流进口(9)至供氧气流出口(10)的流道(81)，相邻两个所述流道(81)之间形成脊背(82)，所述流道层(8)为所述透气率调节结构。
  11. 如权利要求10所述的燃料电池的阴极结构，其特征在于：所述流道层(8)的阴极透气率从供氧气流进口(9)至供氧气流出口(10)逐步增大。
  12. 如权利要求10所述的燃料电池的阴极结构，其特征在于：所述流道层(8)从供氧气流进口(9)至供氧气流出口(10)的方向被分为三个区域，分别为宽脊背区(83)、中脊背区(84)和窄脊背区(85)，所述宽脊背区(83)、中脊背区(84)和窄脊背区(85)的流道(81)与脊背(82)的宽度的比值逐步变大。
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001135326A (ja) * 1999-11-05 2001-05-18 Fuji Electric Co Ltd 固体高分子電解質型燃料電池および同スタック
CN1658422A (zh) * 2005-03-23 2005-08-24 武汉理工大学 一种燃料电池用气体扩散层及其制备方法
CN1823443A (zh) * 2003-06-10 2006-08-23 百拉得动力系统公司 具有不均匀渗透性的流体分配层的电化学燃料电池
CN102089911A (zh) * 2008-07-15 2011-06-08 戴姆勒股份公司 用于燃料电池布置结构的、尤其用于布置在两个相邻的膜电极布置结构之间的双极性板
CN102456891A (zh) * 2010-10-29 2012-05-16 中国科学院大连化学物理研究所 一种具有梯度孔结构的气体扩散层及其制备和应用
CN105917506A (zh) * 2014-01-16 2016-08-31 奥迪股份公司 具有多种密度的燃料电池微孔层

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001135326A (ja) * 1999-11-05 2001-05-18 Fuji Electric Co Ltd 固体高分子電解質型燃料電池および同スタック
CN1823443A (zh) * 2003-06-10 2006-08-23 百拉得动力系统公司 具有不均匀渗透性的流体分配层的电化学燃料电池
CN1658422A (zh) * 2005-03-23 2005-08-24 武汉理工大学 一种燃料电池用气体扩散层及其制备方法
CN102089911A (zh) * 2008-07-15 2011-06-08 戴姆勒股份公司 用于燃料电池布置结构的、尤其用于布置在两个相邻的膜电极布置结构之间的双极性板
CN102456891A (zh) * 2010-10-29 2012-05-16 中国科学院大连化学物理研究所 一种具有梯度孔结构的气体扩散层及其制备和应用
CN105917506A (zh) * 2014-01-16 2016-08-31 奥迪股份公司 具有多种密度的燃料电池微孔层

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