Thermal management is the crucial issue for polymer electrolyte fuel cells (PEFCs). This demands two challenging tasks for the system performance and the reliability; the membrane temperature must be kept within a certain range, and the generation of a hot spot must be avoided. In order to tackle this problem, a novel theoretical approach must be developed that considers both the electrochemical and the heat transport processes. In this study, the coupling phenomena of electrochemical reaction and heat transport in PEFC have been analyzed by using a newly developed simulation model. Effects of the various parameters on the thermal characteristics have been studied, and the mechanism of the hot spot generation on the membrane has been discussed. The validity of the present model has been confirmed by comparing with experimental results. It has been revealed that sufficient humidification and low utilizing rate of oxygen are effective to avoid the hot spot generation and to establish the uniform membrane temperature in the longitudinal direction.
