Engineering Artificial Protrusions of Zn Anodes for Aqueous Zinc Batteries.

Uncontrollable dendrite growth can jeopardize the cycle life of aqueous Zn batteries. Here, we propose a general strategy of engineering artificial protrusions (APs) on the electrode surface to regulate the distribution of the electrode interface electric field and induce stable Zn plating/stripping for Zn batteries. The junction-free AP-Cu network is constructed on Cu foil by an ultrafast Joule-heating-welding method. COMSOL simulation reveals that a stronger microelectric field is formed around the individual AP, which can effectively regulate a uniform nucleation of Zn on the AP-Cu network. Guided by the structural advantages of the AP design, the AP-Cu∥Zn cell delivers an average Coulombic efficiency (CE) of 99.85% at 2 C with an areal capacity of 1.77 mAh cm for over 3000 cycles. Moreover, the AP design enables stable cycling of both Zn|AP-Cu∥VO and anode-free AP-Cu∥Br full cells, providing a promising strategy for the development of high-performance energy storage devices.