Strategy for Using Electrolyte Additives to Regulate Zinc-Ion Battery Anode Interfaces via Tautomerism.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Zinc-ion batteries (ZIBs) face challenges like dendrite formation and poor cycling stability.
• Anode/electrolyte interface (AEI) instability is a key limitation in ZIB performance.

Purpose of the Study:

• To investigate the role of 1,3-Dihydroxyacetone (DHA) as an additive in ZIBs.
• To understand how DHA modulates the AEI and improves electrochemical performance.
• To evaluate the impact of DHA on zinc deposition and battery stability.

Main Methods:

• Density Functional Theory (DFT) calculations to study molecular interactions.
• Experimental characterization of battery components and performance.
• Electrochemical testing of symmetric ZIBs, full cells, and capacitors.

Main Results:

• DHA stabilizes the anode by modifying the AEI, reducing dendrite formation and hydrogen evolution.
• DHA's keto-enol tautomerization minimizes anode surface concentration gradients.
• Zn||Zn symmetric batteries achieved 400 h cycling stability at 56.7% DOD.
• Zn||VNNC full batteries demonstrated 700 cycles at 5 A g^-1 with a low N/P ratio.
• Zinc-ion capacitors (ZICs) showed significantly enhanced performance.

Conclusions:

• DHA is a promising additive for improving ZIB performance and stability.
• Molecular-level understanding of DHA's mechanism provides insights for future battery design.
• The study highlights the potential of DHA in advancing ZIB technology.