A thorough understanding of the flow characteristics of vanadium redox-flow batteries is essential for their improvement. With a combined approach of CFD simulations linked with optical measurements, the distribution in a carbon felt electrode of the vanadium electrolyte as well as of an alternative fluid substitute is compared and in all three dimensions analyzed leading to qualitatively consistent results. Yet, the experimentally observed partially inhomogeneous flow distribution is not predicted by the pseudo-homogeneous porous media CFD model.
Different flow field designs are known for vanadium redox-flow batteries (VFB). The best possible design to fulfil a variety of target parameters depends on the boundary conditions. Starting from an exemplary interdigitated flow field design, its channel and land dimensions are varied to investigate the impact on pressure drop, channel volume, flow uniformity and limiting current density. To find a desirable compromise between these several partly contrary requirements, the total costs of the VFB system are evaluated in dependence of the flow field’s dimensions. The total costs are composed of the electrolyte, production and component costs. For those, the production technique (injection moulding or milling), the pump and nominal power density as well as depth of discharge are determined. Finally, flow field designs are achieved, which lead to significantly reduced costs. The presented method is applicable for the design process of other flow fields and types of flow batteries.
Graphical abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.