Trinity Cooperative Electrode as a High-Performance Electrocatalytic Host for Ultra-Stable, High-Rate Zinc-Halogen...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc-halogen batteries (ZHBs) are promising for safe, low-cost energy storage.
• Key challenges include halogen dissolution, shuttle effects, and slow interfacial kinetics, limiting performance and lifespan.

Purpose of the Study:

• To develop a novel electrode material to overcome limitations in aqueous zinc-halogen batteries.
• To enhance electronic conductivity, mechanical/solvent stability, and halogen immobilization within the battery system.

Main Methods:

• Integration of a conductive polymer, supramolecular solvent matrix, and elastic polymer network into a trinity cooperative electrode (TCE).
• In situ/ex situ characterizations and molecular dynamics simulations to elucidate the iodine conversion pathway.
• Electrochemical testing of TCE-based cells in various zinc-halogen electrolytes.

Main Results:

• TCE-based cells in ZnI2 + Zn(CF3SO3)2 electrolytes achieved 255 mAh g-1 at 1 A g-1 and retained 150 mAh g-1 at 50 A g-1 for over 50,000 cycles.
• Reliable operation was demonstrated at -10°C.
• The TCE effectively catalyzed Br-/Br2 conversion and enabled sequential multielectron reactions in ternary electrolytes, achieving ~200 mAh g-1 at 30 A g-1 for over 22,000 cycles.

Conclusions:

• The trinity cooperative electrode significantly advances aqueous zinc-halogen battery technology.
• This approach leads to high-energy, long-life ZHBs by leveraging pseudocapacitive interfacial chemistry.
• The developed electrode material offers a viable solution for safer and more efficient energy storage systems.