Date of Award
Master of Science (MS)
Redox flow batteries (RFB) hold great potential for large-scale stationary energy storage. However, their low energy density compared to other energy storage systems must improve for feasibility. Electrolyte flow distribution affects current density distribution and providing a uniform current density distribution is one way to improve RFB performance. Additionally, reducing the power consumption of the electrolytes’ pump as a source of energy loss in RFB systems increases their efficiency. Investigating both subjects requires analysis of the fluid dynamics in RFB cells.
In this thesis, a novel, computationally cost-effective hydraulic-electrical analogous model (HEAM) was developed to study fluid dynamics by implementing scaling analysis on Navier-Stokes and Darcy’s equations. The accuracy of the model was tested by comparing it to experimental data, and it proved to be more accurate than other similar models in the literature. HEAM demonstrated the deficiencies of flow distribution in interdigitated flow fields (IFF) and suggested that lower viscous resistance at the flow distribution manifold or higher resistance in the xiv parallel channels remedies the flow maldistribution. Further analysis showed that RFBs with IFFs need lower pump power to operate than those with serpentine flow fields (SFF) with similar properties. The HEAM may serve as an accurate tool for predicting the electrolyte flow behavior in RFB cells in future analyses. Moreover, this study indicates numerous ways to improve the electrolyte flow distribution of RFB cells with IFF and demonstrates the appeal of IFFs despite their complicated geometry and deficiencies for large-scale RFB applications.
Palghat Ramachandran Benjamin Kumfer