Stabilizing Zinc Anodes with Water-Soluble Polymers as an Electrolyte Additive

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aqueous zinc-ion batteries face anode instability due to water-induced corrosion and zinc dendrite formation.
• These issues disrupt the zinc plating/stripping process, limiting battery lifespan and performance.

Purpose of the Study:

• To investigate the use of water-soluble polymers as electrolyte additives to stabilize zinc metal anodes.
• To evaluate the effectiveness of polyacrylic acid (PAA), polyacrylamide (PAM), and polyethylene glycol (PEG) in mitigating anode degradation.

Main Methods:

• Three water-soluble polymers (PAA, PAM, PEG) were added to ZnSO4 electrolytes.
• Electrochemical performance of zinc anodes was tested with these additives.
• Zinc plating/stripping stability and dendrite formation were analyzed.

Main Results:

• The polyacrylic acid (PAA)-based system demonstrated superior electrochemical performance.
• Stable cycling exceeding 360 hours was achieved at 5 mA cm⁻² with 2 mA h cm⁻² areal capacity.
• PAA effectively suppressed zinc dendrite growth, electrode corrosion, and side reactions.

Conclusions:

• Polyacrylic acid (PAA) is a highly effective electrolyte additive for stabilizing zinc anodes in aqueous zinc-ion batteries.
• The carboxyl groups in PAA play a crucial role in suppressing detrimental interfacial reactions.
• This study provides a valuable reference for optimizing zinc anodes for enhanced battery performance.