Posted by Redox flow batteries have a unique architecture that potentially enables cost-effective long-duration energy storage to address the intermittency introduced by increased renewable integration for the decarbonization of the electric power sector. Targeted molecular engineering has demonstrated electrochemical reversibility in natively redox-inactive ketone molecules in aqueous electrolytes. However, the kinetics of fluorenone-based flow batteries continue to be limited by slow alcohol oxidation. We show how strategically designed proton regulators can accelerate alcohol oxidation and thus enhance battery kinetics. Fluorenone-based flow batteries with the organic additive β-cyclodextrin demonstrate enhanced rate capability, high capacity, and long cycling. This study opens a new avenue to improve the kinetics of aqueous organic flow batteries by modulating the reaction pathway with a homogeneous catalyst.
Encapsulating fluorenol in β-cyclodextrin molecules would enhancethe solubility when introduced to a flow battery solution. That turned out to be not a very efficient way to deliver more fluorenol, but it did result in a fair amount of β-cyclodextrin making its way into the flow battery.
The Pacific Northwest National Laboratory’s contribution is the first ever use of β-cyclodextrin, in a flow battery formula.
Read more:
Ruozhu Feng, Ying Chen, Xin Zhang, Benjamin J.G. Rousseau, Peiyuan Gao, Ping Chen, Sebastian T. Mergelsberg, Lirong Zhong, Aaron Hollas, Yangang Liang, Vijayakumar Murugesan, Qian Huang, Eric Walter, Sharon Hammes-Schiffer, Yuyan Shao, Wei Wang (2023) Proton-regulated alcohol oxidation for high-capacity ketone-based flow battery anolyte. Joule 7, 1609-1622.
DOI: https://doi.org/10.1016/j.joule.2023.06.013
https://cleantechnica.com/2023/07/12/new-flow-battery-lasts-all-year-on-simple-sugar/