Electric field distribution regulation of a zinc anode toward long cycle life zinc metal batteries

Abstract

Zinc ion batteries are expected to be the next generation of rechargeable aqueous metal ion batteries, but their application is limited by the severe dendrite growth caused by inhomogeneous plating during the plating/stripping process. Herein, we designed a zigzag Zn anode surface using a simple hydrochloric acid etching method to regulate the electric field distribution on the surface. Finite element simulations show that the zigzag Zn anode surface allows for a more uniform current distribution during cycling, and the symmetric cell can exhibit a small overpotential of 42.1 mV under 0.5 mA cm⁻²/0.5 mA h cm⁻² cycling conditions. Furthermore, the assembled zigzag Zn/V₂O₅ battery still delivers a high discharge capacity of 305 mA h g⁻¹ and shows 83.3% capacity retention after 3000 cycles at a current density of 2 A g⁻¹. The construction of special structured surfaces can offer a simple and effective method to regulate the electric field distribution on the surface of Zn anode, leading to a homogenized Zn plating process and suppressed hydrogen evolution reaction as well as inhibited dendrite growth, holding great promise for the application of metal anode based batteries.