Fluorine‐Rich Double‐Network Interfacial Layer Enabling Dynamic Interphase Reconstruction for High‐Capacity Zinc Metal Batteries
Caiyun Chang, Titi Li, Jie Li, Cuiping HanABSTRACT
Developing large‐scale, dendrite‐free zinc (Zn) anodes is pivotal for the practical deployment of aqueous Zn‐metal batteries (AZMBs), yet maintaining interfacial stability under high‐areal‐capacity conditions remains challenging. Here, we report an adaptive artificial solid‐electrolyte interphase (ASEI) based on a single‐ion‐conducting fluorine‐rich double network (SFDN) that enables in situ dynamic reconstruction of the Zn/electrolyte interphase. The SFDN, comprising an Al(OR) 4 − ‐based (R = −CH 2 −(CF 2 ) 7 −CH 2 −) dynamic crosslinked network integrated within PVDF‐HFP matrix, delivers a high Zn 2+ transference number (0.78) and hydrophobic/zincophilic properties. During cycling, residual monomers within the SFDN fulfill a dual‐functional role: coordinating with Zn 2+ to establish a dynamic Zn(OR) 2 − ‐based network while undergoing sacrificial decomposition to form a robust ZnF 2 ‐rich inner SEI. This evolution yields a multilayered architecture that effectively suppresses water‐induced side reactions, homogenizes Zn 2+ flux, and provides self‐healing. Consequently, the SFDN@Zn anode achieves an extraordinary lifespan of over 4,000 h at 10 mA cm − 2 /10 mAh cm − 2 , and a high average Coulombic Efficiency of 99.9% at 5 mA cm − 2 . Furthermore, a ∼900 mAh Zn||I 2 pouch cell achieves a high energy density of 196 Wh kg − 1 with 97.8% capacity retention over 300 cycles. This work presents a dynamic self‐adaptive interphase engineering, offering fundamental insights into Zn‐anode stabilization, and extending to other metal‐based battery systems.