Fuel cell bipolar plate with internal water diversion/internal humidification structure

Abstract

The invention provides a fuel cell bipolar plate, which is characterized in that an oxygen polar plate, a conductive water flow field plate and a hydrogen polar plate are sequentially arranged from one side to the other side of the bipolar plate, at least one of the oxygen polar plate and the hydrogen polar plate of the bipolar plate is an internal water diversion / internal humidification combined plate, the internal water diversion / internal humidification combined plate sequentially comprises a conductive microporous plate and a conductive solid plate with through holes from the outer side to the inner side, and the through hole is covered with a water-guiding and gas-blocking film. According to the invention, during water guiding, a conductive hydrophilic microporous material absorbs water generated by a battery into micropores of the conductive hydrophilic microporous material in situ, and transfers the water to a water guiding area under the action of capillary force, and the water enters a water cavity under the action of pressure difference, so that the generated water is discharged from the surface of an electrode; during humidification, the water in the water cavity sequentially passes through a water-guiding and gas-blocking film and a conductive hydrophilic microporous material and enters a gas cavity to humidify gas, so that the internal humidification function is achieved; and the fuel cell bipolar plate has a good internal water diversion / internal humidification effect.

Description

technical field [0001] The invention belongs to the field of fuel cells, in particular to a fuel cell bipolar plate with an internal water separation / internal humidification structure. Background technique [0002] Fuel cells have the advantages of cleanliness, high efficiency, high power density, and low-temperature fast start-up, and are widely used in vehicle power supplies, distributed power generation, and military fields. Proton exchange membrane fuel cell is currently the most widely used type of fuel cell, which usually uses perfluorosulfonic acid membrane as the solid electrolyte diaphragm. Water management for such batteries is one of the key factors determining their performance and reliability. The purpose of water management is to discharge the water generated by the fuel cell from the electrode surface in time, so that the reactant gas can be efficiently transmitted to the surface of the electrode catalyst for reaction and reduce the mass transfer polarization...

AI Technical Summary

Problems solved by technology

The patent has the following problems: first, the hole diameter of the porous plate is between 0.1mm and 1mm, and the processing is complicated; second, the holes of the porous plate are scattered and not connected to each other, and there is no function of redistributing water by capillary force in the plate. Therefore, its humidification effect depends on the distribution density of pores; the third is that the film is between the entire conductive plate, and the conductivity perpendicular to the plate is greatly affected.

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