Lithium Acetylacetonate Mediated Multidimensional Optimization for Reversible Zn Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc-ion batteries (AZIBs) offer safe, large-scale energy storage but face challenges like zinc dendrites and interfacial instability.
• Uncontrolled zinc deposition and side reactions limit the practical application and cycle life of AZIBs.

Purpose of the Study:

• To develop a multifunctional electrolyte additive to overcome the limitations of zinc anodes in AZIBs.
• To improve the safety, efficiency, and long-term cycling stability of AZIBs through rational molecular design of additives.

Main Methods:

• Introduced lithium acetylacetonate (LA) as a multifunctional electrolyte additive.
• Investigated LA's effects on Zn2+ solvation, water hydrogen-bonding network, and zinc deposition behavior.
• Evaluated battery performance using Zn//Cu half cells, Zn//Zn symmetric cells, and Zn//NH4V4O10 full cells.

Main Results:

• LA reconstructed Zn2+ solvation and suppressed side reactions.
• LA promoted ordered zinc crystal growth, inhibiting dendrite formation.
• Achieved high coulombic efficiency (99.97% over 4000 cycles) in half cells and stable cycling in symmetric and full cells.

Conclusions:

• Lithium acetylacetonate is a highly effective additive for enhancing AZIB performance.
• The molecular design strategy offers a new paradigm for developing advanced electrolyte additives for aqueous multivalent metal batteries.
• Demonstrated a practical solution for achieving long-term cycling stability in AZIBs.