Design And Performance Study Of Air-breathing Proton Exchange Membrane Fuel Cell

Air-breathing proton exchange membrane fuel cell(AB-PEMFC),the cathode adopts open structure,does not require oxygen tank,air compressor and other devices,greatly simplifies the battery power generation system,makes the battery smaller,and is more conducive to the battery to the portable The development of miniaturization.However,the main reason for hindering the widespread application of air-breathing proton exchange membrane fuel cells is their low output power,improved cathode water management capacity,and improved cathode oxygen transmission efficiency are the key to solving the problem.In this paper,the cathode flow channel size and structure were analyzed and studied from the improvement of cathode oxygen transmission and drainage efficiency.In this paper,based on the working principle of the piezoelectric pump,a cathode vibration device is designed to improve the cathode gas supply and drainage of the airbreathing proton exchange membrane fuel cell.The size of the cathode inlet and outlet structures in the cathode vibration device was analyzed and calculated by numerical analysis method.The optimal size of the inlet and outlet structures was obtained,and the resonant frequency was tested by experiments.Secondly,a three-dimensional mathematical model of the air-breathing proton exchange membrane fuel cell was established,and the mathematical model was combined with the finite element analysis software to study the influence of the cathode flow channel size on the internal transmission and battery performance of the battery.The optimal width of the cathode flow channel of the air-breathing proton exchange membrane fuel cell designed in this paper was determined to be 4 mm,and the width of the runner ridge was 1.5 mm.Thirdly,the cathode vibration device is combined with the air-breathing proton exchange membrane fuel cell,and a cathode-vibrating AB-PEMFC is designed.The displacement output response function of the cathode piezoelectric oscillator is obtained by dynamic analysis.The effects of battery operating parameters(cathode vibration frequency and anode stoichiometry)on battery performance were studied by finite element analysis and dynamic mesh techniques.The results show that when the cathode vibration frequency is 180 HZ,the battery output performance is the best;as the anode stoichiometric ratio increases,the battery performance is slightly improved,but when the stoichiometric ratio is higher than 1.4,the battery performance is not obvious,in order to reduce The anode hydrogen is wasted and recovered,and the optimum stoichiometric ratio of the anode should be 1.4.Finally,through the experimental test bench,AB-PEMFC and AB-PEMFC with external vibration of the cathode were tested and compared experimentally.The results show that the limit current density and maximum output power of the externally vibrated AB-PEMFC are increased by 6.8% and 5%,respectively,compared to the unvibrated AB-PEMFC.Moreover,the vibration-affected AB-PEMFC is less affected by the battery operating temperature than the unvibrated AB-PEMFC.