Fluid Physics Impacting Vanadium and Other Redox Flow Batteries

• Published in: Journal of the Electrochemical Society 2024-06, Vol.171 (6)
• Main Author: Krowne, Clifford M.
• Format: Article
• Language: English
• Subjects: battery electrodes; bipolar plates and membrane; compressible and incompressible fluids; deviatoric stress tensor; Navier-Stokes equation; newtonian and non-newtonian motion; stress tensor; vanadium redox flow battery
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/ad5252

The Vanadium redox flow battery (VRFB) has been intensively examined since the 1970s, with researchers looking at its electrochemical time varying electrolyte concentration time variation equations (both tank and cells, for negative and positive half cells), its thermal time variation equations, and fluid flow equations. Chemical behavior of the electrolyte ions has also been intensively examined. Our focus in this treatment is a completely new approach to understanding the physics, chemistry, and electronics of the VRFB. Here, we develop complete theoretical equations by an analytical treatment affecting the fluid flow in the VRFB as well as all other redox flow batteries, providing background derivations applicable for all of the fundamental concepts required to properly understand flow batteries. With these concepts presented, calculations are done to determine actual values for fluid velocity, strain rate, angular fluid velocity, angular momentum, rotational kinetic energy, and gravity effects on fluid velocity in a redox flow battery.