Next-Generation Rechargeable Zinc Batteries based on Advanced 3D Electrode Designs

摘要

Zinc-based alkaline batteries offer compelling alternatives to Li-ion batteries in terms of improved safety and lower cost. Although well-established for commercial and military applications in primary (single-use) forms such as Zn-air and MnO_2-Zn, poor cyclability has hindered the broader use of Zn batteries. Conventional Zn electrodes, typically powder-composite forms, suffer from non-ideal current flux, leading to low Zn utilization and dendrite formation upon extended cycling. We have redesigned the Zn anode in a "sponge" form factor that mitigates many of the historic limitations of Zn batteries. In this study, we demonstrate that Zn sponge anodes achieve Zn utilization up to ～90% (740 mA h g_(Zn)~(-1)) when discharged in either primary Zn-air or Ni-Zn cells. During discharge we periodically sample the corresponding cells to determine open-circuit voltage and impedance as a function of state-of-charge (SoC). The 3D-interconnected "wiring" of metallic Zn within the core of the sponge architecture maintains low cell impedance, even to high depths-of-discharge.