Model based evaluation of alkaline anion exchange membrane fuel cells with water management

摘要

The aim of this work is to improve alkaline anion exchange membrane fuel cell performance with water management. The mathematical model of alkaline anion exchange membrane fuel cells was developed with consideration of the water transport inside the membrane. The effects of key operating parameters such as the cathode relative humidity, anode relative humidity, cathode pressure, anode pressure on the net water flux across the membrane and the cell performance were analyzed with the unbalanced pressure concept to enhance the water back diffusion from the anode side to the cathode side. The increasing of the anode and cathode relative humidity leads to high water content, enhancement of membrane conductivity and reduction of ohmic loss resulting in a significant improvement of cell performance, especially an increase in the anode relative humidity. The high cell performance can achieve with the unbalanced pressure operation and the use of thin membrane is also preferred to facilitate water back diffusion from the anode to the cathode and enhance the cell performance.