Electrochemical interface reconstruction to eliminate surface heterogeneity for dendrite-free zinc anodes

Abstract

Metallic zinc anodes have attracted growing interest for aqueous rechargeable batteries owing to their high theoretical capacity and low cost. However, the practical application of zinc anodes is limited by the low Coulombic efficiency resulted from the irrepressible dendrite growth. Herein, we prove that the dendrite formation under low current density is mainly controlled by the surface heterogeneity. According to this fundamental principle, a facile electrochemical interface reconstruction method is proposed to uniformize zinc deposition and dissolution by initial electrostripping activation under high current density, which can effectively eliminate the influence of surface heterogeneity. The reconstructed zinc anode shows highly reversible stripping/plating behavior and significantly enhanced cycling stability in both symmetric and full cells. Moreover, the zinc-ion hybrid capacitor can steady operate for 8000 cycles with 96% capacity retention after one-step electrochemical reconstruction at an optimal current density based on its rapid charging-discharging ability