A novel rotary serpentine flow field with improved electrolyte penetration and species distribution for vanadium redox flow battery

Abstract

A novel rotary serpentine flow field with increased electrolyte penetration and improved species distribution is proposed for ameliorating performance of vanadium redox flow battery (VRFB). Three-dimensional multi-physical VRFB model was employed to analyze the flow and transport behavior as well as the overall performance of the VRFB with different flow field designs. It was indicated that the VRFB with this new rotary serpentine flow field design exhibits higher discharge voltage and lower over-potential at different states of charge as compared with conventional serpentine flow field and interdigitated flow field, which is mainly attributed to the enhanced mass transport of species from channel region to the porous electrode and improved distribution uniformity of active species inside electrode. Overall, the battery with the rotary serpentine flow field can achieves the highest power-based efficiency during whole discharge process, which is about 4.2% -12.6% higher than that for conventional serpentine flow field and about 1% - 4% higher than that for interdigitated flow field. Besides, it was shown that the battery with the rotary serpentine flow field can result in higher net discharge power at various electrolyte flow rates as compared with conventional serpentine and interdigitated flow fields due to the improved discharge voltage and reasonable pump loss, indicating the superiority of the proposed rotary serpentine flow field.