FAIR-RFB · Engineered Porous Electrodes to Unlock Ultra-low Cost Fe-Air Redox Flow Batteries

This proposal will develop a game-changing paradigm to design, synthesize, and functionalize porous electrode materials with far-reaching consequences in electrochemical science and engineering. Focusing on the Fe-air redox flow battery (FAIR-RFB), which holds promise for low-cost, long duration energy storage, I will employ an interdisciplinary approach bridging (electro)chemical engineering, materials science, and computational design to address the following fundamental challenges: (1) I will elucidate the role of the porous electrode microstructure. I will introduce a new methodology that couples evolutionary algorithms with microstructure-informed simulations to predict ideal electrode geometries. A versatile synthetic platform, non-solvent induced phase separation, will be leveraged to synthesize highly controlled 3D microstructures and train neural networks to accelerate the discovery of optimal geometries. (2) I will determine to what extent surface moieties of the porous electrode influence transport phenomena, kinetics, and durability. I will employ electrografting of select molecules to functionalize porous electrodes and impart functional properties (wettability, activity, stability). I will perform nanoelectrochemical imaging to elucidate the role of electrode-coating-electrolyte phenomena. (3) I will develop a novel electrochemical reactor architecture for high-power Fe-air RFBs. Building upon the two previous developments, I will synthesize tailored iron and air electrodes and leverage polymeric bipolar membranes to realize a high voltage and low resistance electrochemical cell. Advanced imaging techniques, i.e. energy- and wavelength-selective neutron imaging, will be employed to visualize reactive transport phenomena during operation, thus helping to address these questions. The novel approaches developed in FAIR-RFB will enable breakthroughs in performance and durability of large-scale electrochemical energy storage systems.