Stable Zn Anodes with Triple Gradients

• Published in: Advanced materials (Weinheim) Vol. 35; no. 6; pp. e2207573 - n/a
• Main Authors: Gao, Yong, Cao, Qinghe, Pu, Jie, Zhao, Xin, Fu, Gangwen, Chen, Jipeng, Wang, Yuxuan, Guan, Cao
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.02.2023
• Subjects: Anodes; dendrite free; Dendritic structure; Deposition; Design optimization; Electric fields; Electrodes; Energy storage; Ion flux; Materials science; Short circuits; triple gradients; Zinc; Zn anodes; Zn deposition behavior; Zn‐ion batteries; dendrite free; triple gradients; Zn deposition behavior; Zn anodes; Zn-ion batteries
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202207573

Aqueous zinc‐ion batteries are highly desirable for sustainable energy storage, but the undesired Zn dendrites growth severely shortens the cycle life. Herein, a triple‐gradient electrode that simultaneously integrates gradient conductivity, zincophilicity, and porosity is facilely constructed for a dendrite‐free Zn anode. The simple mechanical rolling‐induced triple‐gradient design effectively optimizes the electric field distribution, Zn2+ ion flux, and Zn deposition paths in the Zn anode, thus synergistically achieving a bottom‐up deposition behavior for Zn metals and preventing the short circuit from top dendrite growth. As a result, the electrode with triple gradients delivers a low overpotential of 35 mV and operates steadily over 400 h at 5 mA cm‐2/2.5 mAh cm‐2 and 250 h at 10 mA cm‐2/1 mAh cm‐2, far surpassing the non‐gradient, single‐gradient and dual‐gradient counterparts. The well‐tunable materials and structures with the facile fabrication method of the triple‐gradient strategy will bring inspiration for high‐performance energy storage devices. A triple‐gradient electrode that well integrates gradient conductivity, zincophilicity, and porosity is facilely constructed for a dendrite‐free Zn anode. The triple‐gradient design synergistically optimizes the electric field distribution, Zn2+ ion flux, and Zn deposition behavior, thus preventing dendrite growth and achieving long‐term cycling stability.