INTERFACIAL PHENOMENA AND HEAT TRANSFER IN PROTON EXCHANGE MEMBRANE FUEL CELLS

Water transport and heat transfer are two critical issues for proton exchange membrane fuel cell (PEMFC) commercialization. Proper water and heat management ensure a sufficient reactant transport to reaction sites and high operating temperature, which requires good understanding of water and heat transport in PEMFCs. In this paper, previous studies about interfacial phenomena related to water transport and heat transfer in PEMFCs are reviewed. The interfacial phenomena in different components are discussed in detail. Experimental works have been conducted to visually observe the liquid water interface in PEMFCs. However, difficulty still remains for investigations of interfacial phenomena. Modeling works on interfacial phenomena in PEMFCs involve lattice Boltzmann, pore network, level set, and volume-of-fluid approaches. Different approaches have been applied for different components of PEMFC, and the liquid water interface can be located in all these approaches. Heat transfer in PEMFCs is also introduced. Various heat sources result in diverse heat transfer phenomena and nonuniform temperature distribution in PEMFCs. The components significantly influence heat transfer in PEMFCs. Coupled heat and water transport is a major issue for PEMFC management, and the heat pipe effect has been identified as an important mechanism of coupled heat and water transport. Cooling is important for PEMFC heat management, especially for PEMFCs with a large active area, high temperature, and stack.