A fuel cell bipolar plate with protruding points arranged in the flow channel and its design method

Abstract

The invention designs and optimizes the selection of the positions of the bumps, the selection of the number of the bumps and the distribution of the bumps after the bumps are added at the bottom of the flow channel in the bipolar plate flow field. According to different plate types, cavity design, and bipolar plate horizontal and vertical placement, the number, position and distribution of bumps are arranged according to the design of probability distribution.

Description

technical field [0001] The invention relates to the technical field of manufacturing fuel cell bipolar plates, in particular to a fuel cell bipolar plate with bumps arranged in flow channels and a design method thereof. Background technique [0002] The function of the fuel cell flow field is to provide a medium for the electrochemical reaction, including hydrogen and air, and to discharge the water generated during the reaction out of the flow field. The common bipolar plate design has a linear structure, a meandering structure or a serpentine structure on the surface of the plate, but in the direction perpendicular to the plate surface, the bottom is generally a planar groove bottom structure parallel to the plate surface. The planar trench bottom structure can only provide basic functions for air intake and drainage, but cannot provide the fluid with a velocity component perpendicular to the paper surface, and the planar trench bottom structure cannot promote drainage thr...

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Problems solved by technology

CN110474065A in the prior art provides fuel cell pole plate, bipolar plate and hydrogen fuel cell ", this invention is to be provided with dot-like protrusion on the side of the pole plate facing the membrane electrode, and dot-like protrusion makes described pole plate and A flow channel is formed between the membrane electrodes, but the flow channel of the bipolar plate is completely composed of protrusions, which is a point-like flow field; CN209374562U provides a bipolar plate with wedge-shaped protrusions in the flow channel, wherein the bipolar plate The flow field is composed of a plurality of mutually parallel flow channels. The flow channels include flow channel grooves and flow channel ridges. Wedge-shaped protrusions are arranged on the equal points in the length direction of the flow channel grooves, but the trapezoidal wedge-shaped protrusions It is easy to cause cracking (metal bipolar plate) and chipping (graphite bipolar plate) during processing, and the layout position is not limited. Not only can it not play the role of enhancing mass transfer, but the increase in flow resistance is not significant

Moreover, most of the existing bipolar plate flow fields are two-dimensional flow fields, that is, the reactant gas flows parallel to the plane of the bipolar plate and the surface of the membrane electrode. The new trend of bipolar plate design is to increase the flow velocity of the fluid perpendicular to the direction of the paper surface, thereby increasing the mass transfer resistance, but the design focuses on the three-dimensional shape and size of the bumps, and there is no need to focus on the bumps on the bipolar plate. The distribution in the plane, especially the flow field, is designed, and the number of bumps is not designed. Most design methods belong to random trial and error.

Therefore, the comprehensive influence of the existing technology on the number and distribution of bumps is not clearly defined, and the randomly placed bump structure cannot optimize the performance of the stack

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