Thermo-mechanical phenomena in PEM fuel cells

Abstract

SUMMARYThe experimental and theoretical studying of mechanical effects in running fuel cell is provided. It is shown that under optimized operating conditions it is possible to obtain the electrical performances of fuel cells at about 1 W cm À2. The further improvements can be achieved by means of mechanical effects. In particular, the influence of mechanical properties of seal joints and clamping bolt torques on the electrical performance is studied experimentally. It is demonstrated that rigid seal joints improve the electrical performance in comparison with the soft seal joints. Concerning the influence of the bolt torques, a certain optimal value is found for different types of MEA.The numerical modelling of mechanical stresses in running fuel cell is made. The developed model includes the main components of a real fuel cell (the membrane, the gas diffusion layers, the graphite plates, and the seal joints) and the clamping elements (the steel plates, the bolts, and the nuts). The operating conditions have been taken into account by imposing heat sources and humidity field. The results of modelling illustrate the main mechanical effects arising in the entire fuel cell.

Effect of PTFE loading of gas diffusion layers on the performance of proton exchange membrane fuel cells running at high-efficiency operating conditions

“…Two of the key attributes that the proton exchange membrane (PEM) fuel cells must feature are: to effectively manage the liquid water inside the membrane electrode assembly (MEA) and to enhance the contact between the components of this MEA . In order to achieve this, a gas diffusion layer (GDL), which mainly acts as a gas distributor to the catalyst layer and electronic conductor between the flow‐field plate and the catalyst layer, is normally treated with a hydrophobic agent, such as polytetrafluoroethylene (PTFE) and coated with an infinitesimal thin layer known as the microporous layer (MPL) .…”

Modeling and Analysis of Transport Processes and Efficiency of Combined SOFC and PEMFC Systems

“…Analytical modelling of PEM can, for example, be found in [28], while [29] presents a thermo-mechanical study of PEM fuel cells and a comprehensive review on PEM water electrolysis is provided in [30].…”

Thermal characteristics of an air‐cooled open‐cathode proton exchange membrane fuel cell stack via numerical investigation

“…25,26 For stacks with power outputs below 10 kW, common cooling methods include air cooling, passive cooling, and liquid cooling. 27,28 Liquid cooling is favourable relative to air cooling for high-power applications, when the stack power output exceeds 5 kW. 25,27 While liquid cooling results in a greater heat removal rate, the power required to operate ancillary components can counteract this gain.…”

“…For stacks with power outputs below 10 kW, common cooling methods include air cooling, passive cooling, and liquid cooling 27,28 . Liquid cooling is favourable relative to air cooling for high‐power applications, when the stack power output exceeds 5 kW 25,27 .…”