September 19, 2024
Journal Article

Redox Activity Modulation in Extended Fluorenone-Based Flow Battery Electrolytes with pi-pi Stacking Effect

Abstract

Redox flow battery shows promise for grid-scale energy storage. Aqueous organic redox flow battery is particularly popular due to its potentially low material cost and safe water-based electrolyte. Commonly, redox active molecules used in this field feature aromatic rings, and increasing p-aromatic conjugation has been a popular strategy to achieve high energy density, high power density and reduced crossover in new material design. However, this approach can inadvertently hinder redox activity depending on redox mechanism. This study reveals the underlying p-p stacking effect in extended aromatic redox active compounds, where aromatic radical intermediates are involved in redox process. We report a molecular design strategy to mitigate the negative effect of p-p stacking by altering solvation dynamics and introducing molecular steric hindrance.

Published: September 19, 2024

Citation

Feng R., X. Zheng, P.S. Rice, J.D. Bazak, A.M. Hollas, Y. Shao, and Y. Liang, et al. 2024. Redox Activity Modulation in Extended Fluorenone-Based Flow Battery Electrolytes with pi-pi Stacking Effect. Journal of the Electrochemical Society 171, no. 9:Art. No. 090501. PNNL-SA-186885. doi:10.1149/1945-7111/ad7324