Spiral-potato-like nanostructure COF enabling nearly unidirectional zinc deposition for Ah-level pouch cells.

Duan, Fengxue; Li, Qi; Wu, Xiaohui; Chen, Xinyi; Zeng, Zixiong; Wu, Tianyu; Zhang, Haifu; Chen, Yuting et al. · Sci Adv · 2026

basic_science · Level V

Where this comes from

Abstract

A major challenge in realizing ampere hour (Ah)-level aqueous zinc (Zn) ion pouch batteries (Ah-level AZIBs) is the requirements for high Zn utilization rate coupled with even Zn nucleation/growth. Here, we report a spiral-potato-like covalent organic framework (SP-COF) nanostructure to construct isotropic solid electrolyte interphase for Ah-level AZIBs. Compared with conventional COF nanostructures, the unique spiral-potato-like SP-COF combined with affinity sites and porosity enables isotropic interfacial regulation to achieve nearly unidirectional Zn deposition following the theoretical three-dimensional nucleation curve. As a result, symmetric cells based on SP-COF/Zn electrode display ultrastable plating/stripping over 2800 hours at 10 milliamperes per square centimeter. The successfully assembled Ah-level triple stacked layer pouch cell (SP-COF/Zn||I<sub>2</sub>, 1.2 Ah) demonstrates stable cycling over 200 cycles with an ultrahigh Zn utilization rate of 40%. The pouch cell achieves an unprecedented energy density of 156 watt-hours per kilogram. These findings highlight the strategic fine-tuning of COF-based battery architectures to be a promising route for high energy density Ah-level AZIBs.