Investigation In The Effect Of Gas Purging On The Performance And Component Of PEMFC With Dead-ended Anode And Cathode

Proton Exchange Membrane Fuel Cell(PEMFC)is a power conversion device which translates chemical energy contained in reactant gas into electrical energy directly.Prominent advantages such as high energy conversion efficiency,high reliability,environment friendly,low noise,low working temperature,wide range of application and long life make it more and more popular.The objection of this paper is to investigate the purging characteristic and its effect on the membrane electrode assembly(MEA)components,the results deduced in this paper is very important for PEMFC to be used in some special areas.It has been studied that the purging characteristics of PEMFC with dead-ended anode and cathode under different gas pressure.The conclusions are drawn:Higher operating pressure is helpful for the decrease of fuel cell performance,which shows the better performance and slower decrease rate under the same current density.It has been studied that the operating characteristics and performance durability of PEMFC with dead-ended anode and cathode with different proton exchange membranes.The conclusions are as follows:Fuel cell with Nafion~?XL membrane shows higher resistant and less performance than that with Nafion~?211 membrane,whereas the former can get longer durability.Moreover,the hydrogen permeability of both fuel cells was fluctuated within certain range till the failure of the operation.The effects of purging on proton exchange membrane,catalyst and gas diffusion layer are also investigated in this paper.After purging,the thickness of border was thinner than that in the middle of the membrane.More cracks were observed at the border than that in the middle according to SEM analysis in the catalyst.The cracks were increasing with the purging time and operation pressure.However,there wasn't obvious variety of contact angle in gas diffusion layer during the purging process.