In-Depth Analysis of Transport Delay on Cell Performance and Modeling Precision for All-Vanadium Flow Battery

Abstract

The transport delay associated with fluid movement within the pipe inevitably exists in the piping system of a flow battery and this can impose a notable impact on battery design and operational performance. In this paper, comprehensive numerical all-vanadium flow battery models with and without transport delay are proposed on the basis of mass balance. Based on such models, the cell performance and prediction precision are evaluated for different cell designs and various operational conditions. The simulation results demonstrate that it is preferable to adopt a longer and thicker piping, a relatively high flow rate, a small electrolyte volume, a high electrolyte concentration, and an appropriate current density for flow battery design and operation. Furthermore, transport delay can be minimized for energy efficiency investigation and incorporated for electrolyte utilization analysis. Such in-depth studies can significantly help to optimize the cell design and operation management and effectively guide the establishment of the mathematical models for flow battery as well.