Given that the share of renewable energy sources in the world’s power mix is steadily increasing in response to treaties and actions against climate change, energy storage systems have become a crucial player to offset the intermittence coupled with renewable energy sources and allow to match production and demand. In this respect, flow batteries (FBs) offer an enormous potential for future worldwide large-scale battery capacity, given they are capable of storing large amounts of energy in an efficient way. Amongst all FBs, the all-vanadium flow battery (VFB) is the most upcoming energy storage technology because they offer several advantages compared to Li-ion batteries. They decouple power and storage capacity making them easily scalable. In addition, they are flexible and offer a long life cycle and zero long term cross-contamination. While significant attention has already gone towards improving the efficiency and power density of VFBs, there is still a lot of room for improvement, especially in terms of reducing the energy losses inherent to the system. In this regard, the electrode design has a critical role as it simultaneously impacts reaction kinetics, resistivity and mass transport, which should all be optimised to maximise performance. By designing and developing porous carbon electrodes with precisely tunable geometry and composition, this project tends to improve the overall battery performance. Besides the instantaneous battery performance, another important parameter is its lifetime, which has received far less attention. This because lifetime analysis is difficult and time consuming, hindering its uptake in industry. This project will tackle this issue by combining degradation analysis with physicochemical characterisation to establish the main degradation pathways and find solutions to overcome them. Moreover, to predict battery performance physics driven lifetime analysis models will be set up. As such this project will provide a benchmark for future development and research in the field of FBs.