Redox flow batteries represent a remarkable low cost alternative for grid-scale energy storage. They often employ carbon felts as the electrodes, but the activity towards the redox reactions are often poor, leading to low operating power densities. Additionally, the complex flow characteristics of the electrodes are often not well understood. This project aims to synthesise novel electrode structures from sustainable carbon sources via electrospinning, which will allow control of physical characteristics such as porosity, surface area and fibre size, but also to incorporate chemical species that help enhance the kinetics of the redox processes. Advanced x-ray imaging will provide a unique insight into the microstructural properties of the electrodes, and electrochemical testing in a full flow battery system will help identify new materials that will lead to improved flow battery performance and durability.