Biomineralization-inspired dendrite-free Zn-electrode for long-term stable aqueous Zn-ion battery

Abstract

Rechargeable aqueous Zn-ion batteries (AZIB) are a promising type of energy storage device but suffer from the growth of uncontrollable Zn dendrites, which result in the shortcut of the battery. Herein, inspired by the regulated nucleation and growth of inorganic minerals from porous organic matrix within the biomineralization process, dopamine derived N-doped carbon spheres with abundant gaps and voids are assembled onto the Zn metal anode (Zn@C) as an artificial solid electrolyte interphase (SEI) layer to modulate the nucleation and growth of a smooth Zn layer without dendrites and suppress the corrosion and hydrogen evolution side reactions. When assembled into Zn-ion batteries, the bioinspired electrode presents comprehensive enhancements in terms of capacity, rate performance, and stability. This unique design of electrode allows long-term stable cycling up to 2100 h at 5 mA cm−2 for a symmetric battery and gives rise to the performance of 315 mAh g−1 at 0.5 A g−2 and 95% retention of its original capacity after 1000 cycles for the Zn@C//V2O5 pouch cell, which outperform most of reported Zn electrodes. The flexible pouch cells displace significant durability towards folding, bending, and piercing, demonstrating its capability for practical applications in wearable devices.