ENGINEERING DEVELOPMENTS ON VANADIUM FLOW BATTERIES

This work constitutes a contribution to the technological development and optimization of flow batteries systems. The main activities which have been carried out by the author are reported hereafter: 1. Development and assembly of a flow battery cell testing facility; 2. Characterization of new active materials such as membranes and electrodes; 3. Design an electrochemical reactor to perform a regeneration process of the electrolyte to improve the lifecycle of the VFB systems; 4. Identify the best techniques to minimize losses due to shunt currents; 5. Perform an economic analysis to see the impact of the cost of each component on the CAPEX and OPEX of VFB systems. This topic has a strong multidisciplinary focus and requires expertise in mechanical engineering, electrical engineering, materials science, electrochemistry, chemistry, and modelling by means of computational simulations. Accordingly, future activities are planned in terms of collaboration with universities, research institutes (both national and international) to conduct this new research field. This topic was first proposed by my supervisor Prof. Massimo Guarnieri and its importance is also recognized by many groups, for example, first by the groups of the University of Southampton (UK), University of New South Wales (Australia) and Fraunhofer (Germany). Some of the main guidelines for driving future research on IS-VRFBs are identified as follows:  Testing a regeneration system in an industrial-size VFB system;  Testing innovative and advanced techniques to improve the hydraulic seal;  Testing new types of electrodes (i.e., carbon paper) and membrane (i.e., without fluorine);  Developing accurate measurements of the SOC as a function of OCV by means of a potentiometric titration  Advanced methods for SOC prediction using numerical techniques;  Development of a general multiphysics dynamic numerical model that considers the electrolyte flow through homogeneous porous electrodes coupled to the electrochemical kinetics and mass transport, in collaboration with the Division of Fluid Dynamics at Chalmers University of Technology (Sweden);  Investigation on the electrolyte volume change during charge/discharge operations;  Simulation of polarization curves as a function of several control parameters by means of an advanced numerical model.