Initiating a composite membrane with a localized high iodine concentration layer based on adduct chemistry to enable highly reversible zinc–iodine flow batteries
Yichan Hu, Tao Hu, Yuanwei Zhang, Haichao Huang, Yixian Pei, Yihan Yang, Yudong Wu, Haibo Hu, Guojin Liang, Hui–Ming Cheng
Abstract
, ZIFBs utilizing a MgO-LHIC composite membrane exhibited improved coulombic efficiency (CE) and energy efficiency (EE) of 96.3% and 68.6%, respectively, along with long-term cycling stability of 170 cycles. These results significantly outperform those of ZIFBs based on a blank polyolefin membrane (78.2%/61.9% after 60 cycles) and the widely used commercial Nafion N117 (67.8%/53.0% after 23 cycles). Even under high-temperature conditions (60 °C), the LHIC-based battery still demonstrates superior CE/EE of 95.1%/67.5% compared to those of the blank polyolefin membrane (CE/EE: 61.1%/46.8%). Our pioneering research showcases enormous prospects for developing high-efficiency and low-cost composite membranes based on adduct chemistry for large-scale energy storage applications.