Analysis of low-pressure evaporatively cooled polymer electrolyte membrane fuel cells

The polymer electrolyte membrane fuel cell is being proposed for a number of power generation systems. With regard to replacing conventional technologies, they offer many advantages including quiet operation with low emissions. However, the key issue for the success of fuel cell system will be a superior operational efficiency. The associated subsystems for controlling fuel cell stack thermal and water management contribute significantly to the reduction in stack weight and volume and increase the associated operational parasitic losses. In this thesis a novel fuel cell operational method has been proposed which utilises a combined humidification and cooling mechanism based on the direct injection of liquid water to the cathode flow-field. Several analyses were performed to investigate critical issues for the workable concept of such an EC, or evaporatively cooled, fuel cell system. [Continues.]