Method for effectively relieving anode poisoning of proton exchange membrane fuel cell by differential pressure oxygen permeation

Abstract

The invention relates to a method for effectively relieving anode poisoning of a proton exchange membrane fuel cell by differential pressure oxygen permeation. According to the method, back pressure is applied to the cathode of the fuel cell, and pressure difference is generated on the two sides of the cathode and the anode, so that air on the cathode side permeates into the anode through a proton exchange membrane, impurities such as hydrogen sulfide and carbon monoxide adsorbed on an anode catalyst are oxidized by oxygen permeated into the anode, and the anode poisoning of the fuel cell is relieved. The method adopted by the invention is simple and easy to implement and high in operability, and has feasibility for relieving poisoning of the fuel cell.

Description

technical field [0001] The invention belongs to the field of proton exchange membrane fuel cells, and in particular relates to a method for effectively alleviating the poisoning of the anode of the proton exchange membrane fuel cell by utilizing pressure difference to permeate oxygen. Background technique [0002] The durability of proton exchange membrane fuel cells (PEMFC) is one of the key factors restricting the large-scale commercial application of hydrogen energy in the transportation field. After a fuel cell passenger car has been driven for 5000 hours, the output performance attenuation should be less than 10%. At present, my country's vehicle fuel cell hydrogen mainly comes from industrial by-product hydrogen, which contains trace impurities, such as H 2 S, CO, NH 3 , CO 2 , formaldehyde, formic acid and light hydrocarbon components, etc., have an important impact on the durability of fuel cells. [0003] Among hydrogen impurities, H 2 The poisoning of PEMFC by ...

AI Technical Summary

Problems solved by technology

Among them, the method of introducing pure hydrogen into the anode side can restore the performance of PEMFC to a certain extent, but the recovery ratio is low (~70%), and the higher the impurity gas concentration is, the smaller the recovery ratio is; using ozone through the anode can partially restore the H 2 The PEMFC performance after S poisoning (85%-99% battery performance can be recovered), but the strong oxidation of ozone has certain harm to the membrane electrode, which may lead to the decrease of the hydrophobicity of the catalyst layer and the degradation of the conductive polymer; through the anode 0- Electrochemical oxidation induced by potential sweeping at 1.4 V can fully restore the performance of PEMFC

However, this method needs to feed hydrogen gas into the cathode as the reference electrode, and nitrogen gas into the anode as the working electrode. The operation is too complicated, and it is not suitable for the practical application of fuel cells in application scenarios such as electric vehicles and stationary power stations.

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