An article by Smith group alumnus Dr. Venkat Pavan Nemani (now a postdoc at Iowa State University) was recently published in the Journal of the Electrochemical Society [Nemani and Smith, J. Electrochem. Soc., DOI: 10.1149/1945-7111/ab9b0d (2020)].  While the modeling of many devices for electrochemical energy storage and water treatment has been democratized by access to commercial and open-source software (e.g., COMSOL, OpenFOAM, and Ansys Fluent), the specific techniques needed to perform robust, reliable, and accurate simulation of the complex processes occurring in those devices are often not reported in the literature.  This article of our’s attempts to bridge that gap by showing that certain conditions must be satisfied to solve the highly coupled equations that govern the simultaneous transport of charge and reactions rates in electrochemical devices.  Further, we introduce several numerical techniques that can be used to make the simulation of such processes robust to operating conditions and design parameters.  While the present article is posed specifically for electrochemical energy storage using redox flow batteries, the issues raised and the techniques introduced readily apply to other electrochemical devices for energy storage and water treatment as well.