Non-destructive stripping electrochemistry enables long-life zinc metal batteries

Abstract

Current research focuses on regulating Zn plating behavior to address the dendrite issue. Although significant improvements in the lifespans of symmetric batteries have been achieved, full batteries do not demonstrate a corresponding increase in the overall lifespan. The underlying reasons for this discrepancy remain unexplored. Herein, we identify that this performance mismatch is attributed to the neglect of the initial stripping behavior of the zinc anode in practical full batteries. This initial stripping, characterized by inherent inhomogeneities, causes anomalous and localized detachment of the interface layer. The incompleteness of the interface layer will result in the failure of its protection function. Then a non-destructive stripping strategy involving instantaneous repair of the damaged region is proposed to maintain the structural and functional integrity of the interface layer. During prolonged cycling, the copper–zinc species within the interface layer undergo irreversible phase reconstruction and spatial redistribution, which facilitate the de-solvation of hydrated Zn²⁺ and determine the plating of large-sized Zn(002). Utilizing this non-destructive anode, the full battery demonstrates a lifespan increase comparable to that of a symmetric battery, achieving an ultralong lifespan (1240 hours, 800 cycles) at a low current density (0.246 A g⁻¹) with an ultrahigh cumulative capacity (847 mA h cm⁻²), and an Ah-level pouch cell exhibiting 150 stable cycles is also validated.