Two-layer hydrodynamic network model for redox flow battery stack with flow field design

Abstract

A two-layer hydrodynamic network model is proposed to analyze the electrolyte distribution within a redox flow battery (RFB). The proposed model consists of a channel, a porous electrode, and an interconnection part through which the electrolyte flows through the channel and porous electrode. The flow rate and pressure drop of each network component are calculated using the Hardy-Cross method. The predicted pressure drop is consistent with experimental and three-dimensional computational fluid dynamics (CFD) results. The velocity and pressure distributions are also in good agreement with CFD results. Furthermore, the proposed model analyzes the flow distribution of cells in RFB stacks with different flow field designs. The results show that the flow rate difference between the first and last cells of the RFB stack with an interdigitated flow field is 20 times higher than that of a flow-through-type.