Battery performance optimization and multi-component transport enhancement of organic flow battery based on channel section reconstruction

The mass transfer behaviors in porous electrodes are the main barriers for organic redox flow battery performance except optimizing microscopic modification of active materials. In this study, a three-dimensional numerical model is established based on electrochemistry dynamics and hydromechan-ics, which is verified by lots of experiments. Due to Reynolds number and hydromechanics influenced by channel section shapes, the mass transfer behaviors and battery performance are influenced by the channel section shapes. The results show that the semicircular channel section needs the lowest charging voltage and discharges the highest voltage. The average concentration of 2,6-reDHAQ ions in semicircle flow channel is up to 19.1% higher than that of triangular flow channel and 11.7% higher than that of the common rectangular flow channel. During discharge, uniformity factors of semicircular design is 16.2% higher than that of triangular flow channel and 11.3% higher than that of rectangular flow channel. What's more, the semicircular design presents the best performance in the power-based efficiency, input and output work under different flow rates and initial concentrations. It is concluded that semicircular is the best design of channel section shapes, which can provide a new way to investigate mass transfer behavior in organic redox flow battery. (c) 2022 Elsevier Ltd. All rights reserved.