The demand for energy generation has increased sensibly over the last few years, as well as the need to reduce its impact on the environment. Fuel cell systems are one of the most promising technologies that can help to achieve these objectives.
The main characteristics of fuel cells are their lower noise, pollution emission and their higher energy conversion efficiency (40% and higher) compared to most conventional thermomechanical-based power generation processes (only 25% to 30% at best). However, major developments are still required to reach the performance where fuel cells can be widely commercialized. The performance and life optimization remain very challenging issues as regards the design and manufacturing of fuel cells.
Among the existing fuel cell systems, planar Solid Oxide Fuel Cell (SOFC) is a promising technology that offers a clean alternative to fossil fuels due to its high kinetic activity, its fuel flexibility and its fuel reforming within the cell unit.
The major drawback of this technology is the high operating temperature that can lead to complex materials problems, including residual mechanical stresses due to the different thermal expansion coefficients of the cell components.
To overcome these limitations, in this research project it was proposed to optimize SOFC components to both improve their mechanical reliability and energy conversion performance.
To this end, the optimized porous SOFC microstructure should present sufficient porosity and high connectivity between pores to allow the transit of fuel and oxygen to the cell active sites. Further, this optimized SOFC unit should present an optimized mechanical and transport properties to improve its mechanical reliability and energy conversion efficiency.
The outcome of this research project is the development of a new generation of SOFC, with an optimized anode and cathode porous microstructure, that leads to higher energy conversion and higher life expectancy. As far as academic results are concerned, two Ph.D. theses have been carried out during the research project.