Shaping Porous Electrode Architecture to Improve Current Density and Energy Efficiency in Redox Flow Batteries (SPACER)

Research Project, 2025 – 2029

The energy transition has increased demand for energy storage, including long-duration storage solutions like redox-flow batteries (RFBs). But RFBs are limited by a high levelized cost of storage, due in part to inefficient electrode use and the lack of tailored RFB components.
SPACER will develop high-power-density electrodes for RFBs, with a max. power density of ca. 1Acm-2 and energy efficiencies >85-90% at relevant current densities (20-30% higher than conventional electrodes). The expected cost is up to 50% less than conventional electrodes.

SPACER’s approach is the use of hierarchical structures, i.e. complex multilayer materials. Work will entail:
• Multiscale modelling to better understand RFB behavior and identify hierarchically shaped pore structures for optimum electrolyte and electric flow
• Prototyping of the modelled structures via stereolithic (micro-), 3D printing (meso-) and textile (macroscale) techniques
• Characterization of prototypes via cutting-edge imaging techniques like EPR to validate the models and electrode performance
Three development cycles (micro-, meso- and macroscale) will provide insight into complex interactions and optimal material structures, and culminate in electrodes validated in mini-stacks by industrial partner PIN (TRL6). The intended applications are established (vanadium) and next-gen (HBr) RFBs.

SPACER will give 17 DCs a unique skill set spanning electrochemistry, modelling, material science and cell engineering. The employability of the DCs will be further enhanced by high-quality individual training in scientific and soft skills, and structured network training units moving them from theoretical investigations toward industrial application. The involvement of 3 industrial beneficiaries and a non-funded Industrial Board, secondments in applied research and industry, and a strong training emphasis on market needs will equip the DCs with the intersectoral skills needed for a career in electrochemical energy storage.