Redox Flow Batteries (RFBs) are receiving significant attention as a promising technology for grid storage applications.¹ While there has been great progress in experimental aspects of flow battery technology, there is a lack of modeling approaches to rapidly evaluate system performance. For example, a common practice has been to determine parameters in mathematical RFB models either through conducting experiments or based on the information available in the literature.^2,3,5 However, it is not easy to investigate all parameters for models through this way, and there are occasions when important information, such as diffusion coefficients and rate constants of ions, is not studied. In addition, the parameters needed for modeling charge-discharge are not always available.

In this presentation, we demonstrate that an optimization-based robust modeling framework, which is based on a physics-based electrochemical engineering model and parameter estimation techniques,^2-5 is useful in studying and analyzing RFB systems. We have studied aspects of capacity loss/fade, kinetics, and transport phenomena of the system and further optimized our model using a laboratory-scale all-vanadium redox static cell setup. The practical impact of this work will be reviewed by providing executable files that enable to identify the performance of redox batteries without the need for software installation and a priori programming knowledge.

Acknowledgements

This work was supported by the Clean Energy Institute located in University of Washington, Seattle and Washington Research Foundation. The battery experimental work has been supported by program manager Dr. Imre Gyuk through the U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

References

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