Two Birds with One Stone: Green Solvent Enabled High-Stability and Durable Zn Anode in Both Non-Aqueous and Aqueous Electrolytes

Rechargeable zinc batteries are promising choices for eco-friendly, safe and cost-effective energy storage solutions. However, their commercial adoption faces challenges such as low Coulombic efficiency (CE) and poor reversibility of Zn anodes. To address these issues, a new green electrolyte based on N,N'-Dimethylpropyleneurea (DMPU) has been developed, affording a robust, dendrite-free Zn anode with over 5000 h of cycle stability and a high average CE of 98.49%. Zn anode in DMPU-electrolyte significantly outperforms aqueous electrolyte with 67 times longer cycle life, demonstrating excellent anode stability. Moreover, ultra-stable Zn anode in DMPU-electrolyte cycled for over 10 000 cycles at 1.0 mA cm-2 showcases excellent reversibility. The Dimethylpropyleneurea-triflate anion generated solid electrolyte interphase enables homogeneous and rapid Zn2+-diffusion at the electrode interface, leading to a structured hexagonal Zn deposit. Furthermore, as electrolyte additive, DMPU significantly stabilizes Zn anode at severe conditions (5.0 and 10.0 mA cm-2) along with remarkable enhancement in CE (99.12%). This study offers valuable insights into the development of hybrid and organic electrolytes to advance Zn battery technology. A new green electrolyte based on N, N'-Dimethylpropyleneurea (DMPU) has been developed, affording a robust, dendrite-free Zn anode with over 5000 h of cycle stability and an average Coulombic efficiency of 98.49%. The Dimethylpropyleneurea-triflate anion generated solid electrolyte interphase enables homogeneous and rapid Zn2+-diffusion at the electrode interface, leading to a structured hexagonal Zn deposit. image