Cathode flow field plate for fuel cell and processing method thereof

Abstract

A cathode flow field plate for a fuel cell and a processing method thereof. The cathode flow field plate includes: a flow field plate body; a rectangular concave frame is provided on the flow field plate body; at least four flow channel grooves are provided in the rectangular concave frame; There are at least two flow channel grooves in the rectangular concave surface frame forming a certain acute angle with the rectangular concave surface frame, and at least two flow channel grooves form an opposite angle to the above groove; the flow channel grooves in the rectangular concave surface frame The part between the grooves is a conductive plate; the conductive plate is provided with a matrix-distributed diamond-shaped block three-dimensional structure; the processing method includes: processing a rectangular concave frame on the flow field plate body; Diamond-shaped dot blocks are processed in the frame to finally form a cathode flow field plate with a three-dimensional structure of diamond-shaped dot blocks. The cathode flow field plate provided by the present invention provides sufficient self-breathing gas exchange channels to make oxygen supply more uniform, prevent water droplets from blocking the through holes of the flow field plate, effectively increase the opening ratio, and reduce the dead area of ​​the membrane electrode.

Description

technical field [0001] The invention belongs to the field of fuel cells, and in particular relates to a cathode flow field plate for a fuel cell and a processing method thereof. Background technique [0002] In fuel cells, cathode oxygen supply has a critical impact on cell performance. The cathode structure of the self-breathing fuel cell needs to be exposed to the air environment, and the oxygen supplied depends on diffusion and convection. It needs to pass through the cathode flow field plate, diffusion layer and microporous layer to reach the cathode catalytic layer to complete the catalytic reaction. The cathode flow field plate of the fuel cell has the functions of conducting electrons, transporting oxygen and supporting the membrane electrodes. [0003] The batteries currently used mainly use hole collector plates and parallel collector plates, but it was found during the design process that for fuel cell cathodes, a higher cathode flow field plate opening ratio will...

AI Technical Summary

Problems solved by technology

[0003] The batteries currently used mainly use hole collector plates and parallel collector plates, but it was found during the design process that for fuel cell cathodes, a higher cathode flow field plate opening ratio will reduce the dead zone on the cathode membrane electrode and improve The utilization rate of the catalyst can effectively improve the performance of the battery, but limited by the design and processing methods and materials, it is difficult to achieve an opening rate of more than 60% in the current porous flow field plate and parallel flow field plate

[0004] Traditional dotted flow field plates have a high porosity, but lack gas channels suitable for self-breathing fuel cells

If a completely open structure is used, the membrane electrode of the fuel cell lacks effective mechanical support and current collection, and the battery performance is also poor.

In addition, during the reaction process of the fuel cell, the electrochemical reaction of the cathode will gradually generate excess water to block the pores, inhibit oxygen transfer, reduce the performance of the battery, and threaten the stability of the battery for a long time.

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