Polymer electrolyte membrane fuel cells (PEMFCs) are a key sustainable energy source which can cater for energy demands ranging from miniature power requirements to portable, automotive and various stationary power applications. PEMFCs deliver electricity by means of undergoing electrochemical reactions and produce water and heat as by-products. At high current densities, flooding and overheating can cause local hot spots leading to degradation and failure of the membrane electrode assembly (MEA) during long term operations. Hence, hygrothermal management is normally ensured by means of liquid cooling of the bipolar plates. However, this traditional design incurs extra cost of balance-of-plant (BOP) components and enhances the overall size of the system. Using ambient air as oxidant as well as coolant with an 'open-cathode' design can drastically reduce the system size and weight, however the performance of such a system is limited by overheating and drying of the MEA.
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