Modelling mass transport of reactive species in porous electrodes of redox flow batteries

Abstract

In the recent years, every area of engineering related to energy has found a strong limitation in the field of energy storage. The main problem has appeared with the emergence of renewable generation, which provides cleaner and cheaper energy, but triggers management difficulties to the system operators. Also, the need to find compact energy storage systems has become an urgent demand in sectors like transport. Finally, there is an important commitment for the big energy consumers to increase their energetic efficiency, and the energy storage systems are specially suitable for this purpose. In this thesis, the topic of energy storage will be dealt from the perspective of an emergent technology: the Redox Flow Batteries. The aim of this study is to contribute to the knowledge on the field of the performance of such batteries inside the scientific community. The focus of the study will be the mass transport phenomena that occurs inside the electrodes in which the redox chemical reaction that provides the electric energy takes place. The model of the redox flow battery has been developed from the traditional batteries, in which a porous media catalyzed the reaction of the species. The main feature that contributed to the initial success of the idea of the RFB was the capability that this type of systems showed to decouple energy from power. However, the models were optimized for the past technologies, but not for the flow batteries. The aim of this study is to understand the parameters underlying the tranport phenomena in the electrodes and their effects. Such knowledge can be completed with other reaserch projects in which other characteristics of the flow batteries are studied, and finally a complete model can be built in order to optimize the overall performance of the RFBs.