Multifunctional Polypyrrole Interphase Actively Manages Anion Transport for Stable, High-Rate Zinc Anodes.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Zinc-nickel batteries (ZNBs) offer high voltage, safety, and cost-effectiveness.
• Zinc anode instability in alkaline electrolytes causes dendrite growth and passivation, limiting ZNB performance.

Purpose of the Study:

• To develop a multifunctional artificial solid electrolyte interphase (SEI) for zinc anodes.
• To enhance the stability and performance of ZNBs by mitigating zinc anode degradation.

Main Methods:

• Electropolymerization of a polypyrrole (PPy) film on the zinc anode.
• Fabrication and electrochemical testing of a full ZNB (ZnO@PPy||Ni(OH)2) with the protected anode.

Main Results:

• The PPy layer effectively stabilized the zinc anode, suppressing dendrite growth and passivation.
• The protected ZNB demonstrated high capacity (565 mAh g⁻¹ at 1 C) and excellent cycling stability (245 cycles).
• Exceptional rate capability was observed, maintaining 620 mAh g⁻¹ over 340 cycles at 10 C with 94% capacity retention.

Conclusions:

• Electropolymerized PPy serves as an effective artificial SEI for zinc anodes in ZNBs.
• This strategy significantly improves ZNB performance, enabling high energy density and long cycle life.
• The study presents a viable approach for engineering protective interphases for high-performance zinc-based batteries.