Bipolar plate of proton exchange membrane fuel cell

Abstract

The invention provides a bipolar plate of a proton exchange membrane fuel cell, which consists of a cathode plate and an anode plate, and is characterized in that the cathode plate and the anode plate are formed by stamping metal sheets, a cathode flow field is stamped on the outer side of the cathode plate, an anode flow field is stamped on the outer side of the anode plate, the cathode plate and the anode plate are attached together, and the anode plate and the cathode plate are bonded together. The cathode plate and the anode plate are integrated through laser welding or bonding, and a closed coolant flow field is formed on the inner sides of the cathode plate and the anode plate; and the areas of common channels of the cathodes, the anodes and the coolant inlets / outlets on the anode plates and the cathode plates are asymmetrically arranged. According to the bipolar plate and the flow field structure thereof, uniform distribution of reaction gas can be effectively improved, so that uniform distribution of reaction current is realized, and meanwhile, liquid water and tail gas generated by battery reaction are smoothly discharged; the weight and the thickness of the bipolar plate can be reduced, and the mass ratio power and the volume power of the fuel cell are improved.

Description

technical field [0001] The invention relates to the technical field of fuel cells, in particular to a bipolar plate of a proton exchange membrane fuel cell. Background technique [0002] Compared with traditional energy conversion devices, proton exchange membrane fuel cells (PEMFC) have the advantages of high efficiency, energy saving, safety, and environmental protection, so they have great application prospects. It accounts for more than 45% of the cost of the stack and occupies 70%-80% of the weight of the stack. Therefore, it is necessary to develop bipolar plates with high conductivity, high corrosion resistance, high chemical compatibility, suitable mechanical properties, suitable hydrophilic and hydrophobic properties, and easy mass production to improve the life, reliability and specific power of fuel cells, and then Promote the commercial development of PEMFC. The structure of the bipolar plate directly affects the electrochemical reaction and water heat manageme...

AI Technical Summary

Problems solved by technology

In this design, there will be a problem that the support area of ​​the dot-shaped boss on the MEA is not enough, resulting in the situation that the pressure of the reaction gas cannot be controlled. At the same time, due to manufacturing errors, the cross-sectional area of ​​the coolant channel will decrease and the flow resistance will increase. Seriously affect the performance of the fuel cell

[0004] Chinese Patent Publication No. CN 110212213 A discloses a metal bipolar plate for a proton exchange membrane fuel cell. An anode flow field is provided outside the anode plate, and a cathode flow field is provided outside the cathode plate. The cavity forms the coolant flow field, and the coolant ports are set on the upper and lower sides of the flow field. The advantage is that the vertical cross flow of the coolant and the reaction gas is realized, but the area of ​​the bipolar plate will be increased, or the bipolar plate will be reduced. The area ratio of the activation area will reduce the volume specific power of the fuel cell, and it will also increase the difficulty in the design of the manifold in the later stage.

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