Research progress of heat transfer inside proton exchange membrane fuel cells

Heat is one of the main causes of performance degradation and failure of proton exchange membrane fuel cells (PEMFCs). The 'hot spot' and uneven temperature distribution formed when fuel cells operate can result in the severe degradation of membrane and catalyst layers. To better understand these phenomena, this review presents a systematic and comprehensive summary and discussion on the heat transfer within a PEMFC. Notably, (i) the overall introduction of the basic concept and thermal effect; (ii) the analysis of heat transfer mechanisms, including heat generation and energy transport, as well as the effects of multi-scale; (iii) the summary and discussion of the thermal conductivity and contact resistance of porous media; and (iv) the latest developments in numerical calculation and temperature measurement are crucial. In addition, several outlooks are proposed for further advanced research. We consider that this paper will aid readers in deepening their understanding of this field.