A computationally-cost effective model for fluid flow in redox flow batteries

Redox flow batteries (RFBs) hold great potential for large-scale, extended-duration stationary energy storage. Here, a novel computationally cost-effective hydraulic-electrical analogous model (HEAM) for fluid flow in RFBs is developed. The HEAM demonstrated that lowering the electrode compression and enhancing the channel area lowers the pump power loss independent of the flow fields and electrodes. Additionally, the HEAM helped elucidate the deficiencies of flow distribution in interdigitated flow fields (IFFs) and suggested designing wider manifolds and/or shorter channels improve the flow distribution. Moreover, the HEAM suggested shallower and/or wider channels, and more permeable electrodes enhance the flow penetration rate above the channels. Finally, the HEAM showed that the average penetration depth in the electrode above the ribs (h_pen) was the critical parameter in the fluid-flow modeling of IFFs and was inversely proportional to the permeability. Hence, there is a trade-off between the pump power loss and h_pen when configuring electrode permeability.