Rational Design of Electrolyte Additives Enabling Long-Life Aqueous Zn-Ni Batteries with High Current Density and...

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Zinc-nickel batteries (ZNBs) are promising for green energy storage.
• Traditional electrolytes face issues like dendrite formation and corrosion, limiting ZNB performance.
• Developing stable electrolytes is crucial for advancing ZNB technology.

Purpose of the Study:

• To enhance the stability and cycle life of zinc-nickel batteries.
• To overcome limitations of traditional alkaline electrolytes in ZNBs.
• To explore novel electrolyte additives for improved ZNB performance.

Main Methods:

• Incorporation of sodium polyacrylate (PANa) and trimethyloctadecylammonium chloride (STAC) as electrolyte additives.
• Electrochemical testing of ZNBs, including cycling performance and rate capability.
• Analysis of anode morphology and stability using symmetric cells.

Main Results:

• The modified electrolyte maintained moisture and high ionic conductivity.
• STAC promoted a smooth and dense zinc anode, inhibiting shape changes.
• ZNBs achieved a cycle life of 1168 h at 66.7 mA cm⁻² and 527 h at 100.1 mA cm⁻².
• Symmetric cells showed over 310 h lifespan with 33.4 mAh cm⁻² areal capacity.
• The battery retained 83.7% capacity after 240 h resting.

Conclusions:

• The combination of PANa and STAC effectively stabilizes ZNBs.
• This electrolyte modification strategy significantly improves ZNB performance and cycle life.
• The findings support the commercialization potential and replicability of advanced ZNBs.