| dc.description.abstract | Proton exchange membrane fuel cell (PEMFC) is an electrochemical device that directly converts the chemical energy of reactants into electrical energy. Platinum (Pt) used as a catalyst layer in the PEMFC increases the cost of the fuel cell. This study aims to increase the higher surface area of the catalyst layer with lower catalyst loading. So that the cost of the PEMFC could decrease. When the thickness of Pt membrane exceeds the optimal value, the region with good gas transmission (near the gas diffusion layer) is separated from the region with good proton transmission (near the proton exchange membrane), so the current density and power density decrease with the increase of membrane thickness. In this study, the proton exchange membrane fuel cell is simulated by COMSOL software, and a three-dimensional fuel cell model is established by coupling multiple physical quantities happen in the actual (physical) functioning of PEMFC. The model couples the two-phase flow of multicomponent reactants and liquid water, species transport, electrochemical reaction, proton and electron transport. Based on this model, single cell is simulated with liquid and gaseous media flow in the porous solid system respectively. The simulated region includes the flow channels at both ends of cathode and anode, gas diffusion layer, microporous layer, catalyst layer and proton exchange membrane. In this study, COMSOL multiphysics was used to make different periodic grooves on the surface of cathode and anode microporous layer to increase the effective surface area of Pt deposition, so as to reduce the thickness of Pt membrane. The effects of groove shape, and depth on the performance of PEMFC is investigated. Groove depth increases the performance of PEMFC. The research results show that the groove depth of 40 µm has the highest current density, the better performance of PEM fuel cell. The PEMFC current density is 26% higher at 0.6 V for a square periodic groove of 40 µm. At the same time, the parametric sensitivity analysis of PEMFC with porous flow field design is carried out. The model couples the two-phase flow of multicomponent reactants and liquid water, species transport, electrochemical reaction, proton and electron transport. The research parameters can be divided into the structure or transmission parameters (tortuosity, porosity, permeability and conductivity) of each layer (gas diffusion layer, microporous layer, catalyst layer and proton exchange membrane) and electrochemical parameters (anode and cathode exchange current density, anode and cathode transfer coefficient). Different numerical simulations of single parameters are carried out to obtain the influence of all parameters on the polarization curve of the cell and analyze the factors affecting the performance of the fuel cell. This study helps in decreasing the cost of PEMFC and increasing the performance of PEMFC with optimum Pt thickness and microporous layer groove design. | en_US |