Regulating Zinc Deposition Behaviors by the Conditioner of PAN Separator for Zinc-Ion Batteries

摘要

Aqueous zinc-ion batteries (AZIBs) are promising candidates for large-scale energy storage due to the high safety and cost effectiveness. Yet it is suffered from the obscurely uncontrolled Zn2+ deposition that accumulates together and easily penetrates the separator. Here, a 3D long-range ordered polyacrylonitrile (PAN) nanofiber separator is designed to overcome this barrier. The N atoms on the surface of separator uniformly distribute the ion flux and guide the cation transport through available N-Zn bonds. Hence, the electric field on the anode is evenly distributed, which helps to guide the nucleation, growth, and deposition of zinc ions. Benefit from this functional group, a Zn symmetric cell with PAN separator shows a long-term stability and dendrite-free deposition layer with a preferred (101) crystallographic orientation. Meanwhile, the Zn/NH4V4O10 cells display high specific capacity and excellent long-term durability of 89.2 capacity retention after 1500 cycles at 10 A g(-1). This work demonstrates the design of functional separator provides an effective way to modify Zn2+ deposition behavior and achieve a dendrite-free Zn metal anode.