Galvanic stabilization of Zn metals for long-life aqueous batteries

Abstract

Rechargeable aqueous Zn-ion batteries have received extensive attention due to their environmental friendliness, high safety, and low cost. However, the Zn dendrite growth during plating/stripping cycles, which deteriorates coulombic efficiency and shortens the cycle life, dramatically hinders the application of Zn anodes in batteries. Herein, we propose to grow an In layer on Zn foils through spontaneous Galvanic reaction to address the challenging Zn dendrites. In-situ optical observations show that this strategy effectively suppresses the dendrite growth, thereby leading to a robust and stable Zn metal anode with low voltage hysteresis (30 mV at 0.4 mA·cm−2) and long cycle life of over 1200 h in symmetric cells. Meanwhile, the full cell assembled with the modified Zn anode and MnO2 cathode exhibits excellent cycling performance over 2000 cycles and a high discharge capacity of 89.1 mAh·g−1. This work provides an efficient pathway for interfacial engineering towards stable Zn anodes.