Nanoscale Al2O3 coating by an atomic layer deposition technique enabled safe and dendrite-free Zn anodes for rechargeable aqueous zinc-ion batteries.

No abstract

Aqueous zinc ion batteries (AZIBs) are receiving increasing attention for large-scale energy storage systems owing to their appealing features with intrinsic safety, low cost, and scalability. Unfortunately, the water-induced parasitic reactions and dendrite growth on the Zn anode severely impede the further development of AZIBs. Herein, a thiourea additive is introduced into ZnSO 4 electrolyte to construct unique metal-molecule interface for simultaneously regulating the Zn anode interface chemistry and the bulk electrolyte environment. Experimental results and theoretical calculations reveal that the formed metal-molecule interface can not only serve as a corrosion inhibitor for alleviating the water-induced side reactions, but also act as a Zn 2+ ion regulator for promoting the homogenous Zn deposition, thus achieving a corrosion-free and dendrite-free Zn anode. Consequently, the Zn|Zn symmetric cell exhibits an extended lifespan of 1200 h at 1 mA cm -2 , 1mAh cm -2 , and a high cumulative capacity of 3000 mAh cm -2 at 10 mA cm -2 . When paired with V 2 O 5 cathode, the Zn|V 2 O 5 full cell delivers a high capacity retention of 76.0% after 1000 cycles at 1 A g -1 . This study paves a new way to modulate Zn electrode interface chemistry by the novel design of metal-molecule interface for advanced rechargeable Zn metal batteries and beyond.

Rechargeable zinc-ion batteries (ZIBs) in mild/neutral aqueous electrolytes are promising for large-scale energy storage applications due to their merits of high capacity, intrinsic high safety, low cost and environmental benignity....