Redox Flow Batteries

Redox-Flow Batteries (RFB) offer a unique feature: independent scalability of energy and power. In our research group, we work on the following research lines: 

• Vanadium Redox Flow Batteries (VRFB); using low cost components to obtain a prototype technically and economically viable. We have recently designed and assembled a prototype 5-cell flow battery with large electrodes (3600 cm²) with capacity to store 2.5 kWh of energy at 1.8 kW power. Moreover, we assembled a stack of 100 cells with electrodes of the same dimensions to connect 3 of these stacks in series and perform a testing program for utility-scale solar power plants. The group works also with a process for the preparation of vanadium electrolyte from low cost raw materials. This application reflects the interest of the unit in using fundamental research that can be transferred to the industry.
•  Organic-based RFB; Efforts are focused on finding new, reversible, highly soluble and stable organic redox species (including redox polymers) in aqueous and non-aqueous based electrolytes. Due to the overwhelming number of possibilities, we make use of computational chemistry to guide our experiments.  We establish three sublines in this topic: i) development, optimization and validation of new flow cell systems, ii) search of high-performing electroactive species, iii) understanding of key processes that limit the performance.   
•   Membrane-free RFB; The ultimate objective of this research line is to completely remove the problematic membrane of RFBs by developing a disruptive, versatile and scalable Membrane-Free RFB implementing efficient and immiscible metal-free catholytes and anolytes based on redox active organic molecules. This research line is accomplished within the frame of an ERC Consolidator grant (https://cordis.europa.eu/project/rcn/209738_es.html). 
• Microfluidic RFB; We work on the development of miniaturized flow battery that relies on microfluidic concepts such as laminar flow of electrolytes through microchannels. Different battery chemistries and designs fabricated using 3D printing techniques are being investigated making use of Computational Fluid Dynamics simulation tools.