Ultrastable Zinc Anode by Simultaneously Manipulating Solvation Sheath and Inducing Oriented Deposition with PEG Stability Promoter.

Aqueous zinc-ion batteries are a low-cost and safe energy storage system, but suffer from detrimental side reactions and Zn dendrites due to the strong interactions between Zn2+ and water molecules in the electrolytes, and random Zn2+ deposition on the anode surface. Here, an electrolyte involving a dual-functional additive of polyethylene glycol (PEG) to bypass these issues is reported. The electrolyte can not only tailor the solvation sheath of Zn2+ but also enable favorably oriented deposition of Zn2+ on the anode surface. The dendrite-free Zn anode in Zn//Zn cells is obtained with high Columbic efficiency (98.8%) and long cycling lifespan (1500 h), six times longer than that of electrolyte without PEG at 0.25 mA cm-2 . What is more, the excellent cycling stability of the prepared batteries (Zn//V2 O5 ·1.6 H2 O) suggests that the developed tailoring strategy may propel a promising pathway for stabilizing Zn metal anodes.