Methoxy polyethylene glycol additive regulated electrolyte enables high performance aqueous zinc ion batteries

Abstract

Zinc anodes face critical challenges from dendrite growth and parasitic reactions, severely limiting the practical deployment of aqueous zinc-ion batteries. Electrolyte additives offer a promising approach to stabilize interfacial electrochemistry. To address these issues, we introduce methoxy polyethylene glycol with synergistic functional groups as a multifunctional polymer electrolyte additive to affect the solvation sheath layer of Zn²⁺ and form a stable interface, while inhibiting hydrogen evolution, corrosion and dendrite growth. Remarkably, the additive stabilizes the interface of the electrolyte/zinc anode: Zn||Zn symmetric cells achieve a 16-fold longer lifespan (1300 h vs. 80 h with ZSO electrolyte) at 1 mA cm⁻²/1 mAh cm⁻², while Zn||NVO full cells retain 105 mAh g⁻¹ after 2000 cycles at 1 A g⁻¹. This electrolyte engineering strategy provides an expandable approach for the energy storage of zinc metal batteries with high-safety and long-life.