Ultrahigh-Rate and Long-Life Zinc-Metal Anodes Enabled by Self-Accelerated Cation Migration

Aqueous zinc ion batteries are receiving unprecedented attention owing to their markedly high safety and sustainability, yet their lifespan particularly at high rates is largely limited by the poor reversibility of zinc metal anodes, due to the random ion diffusion and sluggish ion replenishment at the reaction interface. Here, a tunnel-rich and corona-poled ferroelectric polymer-inorganic-composite thin film coating for Zn metal anodes to tackle above problems, is proposed. It is demonstrated that the poled ferroelectric coating can better deconcentrate and self-accelerate ion migration at coating/Zn interface during the electroplating process than untreated ferroelectric coating and bare Zn, thus enabling a compact and horizontally-aligned Zn morphology even at ultrahigh rates. Notably, a maximal cumulative plating capacity of over 6500 mAh cm(-2) (at 10 mA cm(-2)) is achieved for the surface-modified Zn metal anode, showing extraordinary reversibility of Zn plating/stripping. This work provides new insights in stabilizing Zn metal electrodeposition at the scale of interfacial ion diffusion.

Automated summary

A novel ferroelectric polymer-inorganic composite thin film coating is proposed for aqueous zinc ion batteries, which can enhance the reversibility of zinc metal anodes, increase the cumulative plating capacity, and achieve a compact and horizontally-aligned zinc morphology even at ultrahigh rates. This work provides new insights into stabilizing zinc metal electrodeposition at the scale of interfacial ion diffusion.