Intramolecular Hydrogen Bonds Enhanced Quinone-Based Anode for High-Performance Aqueous Proton Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous proton batteries (APBs) are promising for next-generation energy storage, using organic materials as proton charge carriers.
• Conventional quinone-based electrodes face challenges like dissolution and slow kinetics in acidic electrolytes.

Purpose of the Study:

• To design a stable and high-performance organic anode for APBs by addressing limitations of conventional quinone materials.
• To enhance proton transfer kinetics and cycling stability in organic electrodes for aqueous proton batteries.

Main Methods:

• A quinone-based polymer (HMND) with intermolecular hydrogen bonds was synthesized and characterized.
• Proton insertion/extraction mechanisms were investigated using DFT calculations, in situ/ex situ Raman spectroscopy, and FT-IR.
• Electrochemical performance was evaluated in full APBs using a MnO2@GF cathode.

Main Results:

• The HMND polymer exhibited enhanced cycling stability and rate capability due to hydrogen bonding accelerating proton transfer via the Grotthuss mechanism.
• Full APBs demonstrated a long lifespan of 42,000 cycles with minimal capacity decay (0.0018% per cycle at 8 A g⁻¹).
• Exceptional rate performance was achieved (212.5 mAh g⁻¹ at 1 A g⁻¹, 91.4 mAh g⁻¹ at 70 A g⁻¹) and stable operation at -60 °C.

Conclusions:

• The designed quinone-based polymer anode significantly improves the performance and stability of aqueous proton batteries.
• The material's ability to function at extreme temperatures highlights its potential for robust energy storage solutions.
• Hydrogen bonding is an effective strategy for enhancing proton transfer and battery longevity in organic electrodes.