解耦(概率)
水溶液
化学
材料科学
环境科学
化学工程
控制工程
工程类
有机化学
作者
Dawei Xi,Abdulrahman M. Alfaraidi,Jinxu Gao,Thomas Cochard,Luana Cristina Italiano Faria,Zheng Yang,Thomas Y. George,Taobo Wang,Roy G. Gordon,Richard Y. Liu,Michael J. Aziz
标识
DOI:10.1038/s41560-024-01474-1
摘要
Establishing a pH difference between the two electrolytes (pH decoupling) of an aqueous redox flow battery (ARFB) enables cell voltages exceeding the 1.23 V thermodynamic water-splitting window, but acid–base crossover penalizes efficiency and lifetime. Here we employ mildly acidic and mildly alkaline electrolytes to mitigate crossover, achieving high round-trip energy efficiency with open circuit voltage >1.7 V. We implemented an acid–base regeneration system to periodically restore electrolytes to their initial pH values. The combined system exhibited capacity fade rate <0.07% per day, round-trip energy efficiency >85% and approximately 99% Coulombic efficiency during stable operation for over a week. Cost analysis shows that the tolerance of acid–base crossover could be increased if the pH-decoupling ARFB achieved a higher voltage output and lower resistance. This work demonstrates principles for improving lifespan, rate capability and energy efficiency in high-voltage pH-decoupling ARFBs and pH recovery concepts applicable for pH-decoupling systems. Establishing pH differences in aqueous flow batteries widens their voltage window, but acid–base mixing shortens their lifespan. In this study, the authors introduced a pH recovery system to address crossover issues, ensuring long-lasting, high-voltage pH-decoupled flow batteries.
科研通智能强力驱动
Strongly Powered by AbleSci AI