Lithium n-Doped Polyaniline as a High-Performance Electroactive Material for Rechargeable Batteries

Area of Science:

• Electrochemistry
• Materials Science
• Polymer Chemistry

Background:

• Non-aqueous lithium batteries require advanced electrode materials for higher energy density and stability.
• Polyaniline derivatives are explored for their redox properties, but achieving high performance in lithium batteries remains challenging.

Purpose of the Study:

• To synthesize and characterize lithium-doped polyaniline (lithium emeraldinate) for non-aqueous Li battery applications.
• To investigate the electrochemical behavior, capacity, and stability of lithium emeraldinate.

Main Methods:

• Synthesis of lithium emeraldinate via lithium-proton exchange.
• Characterization using UV/Vis-NIR spectroelectrochemistry, XPS, FTIR, and EQCM.
• Electrochemical performance evaluation in non-aqueous Li battery cells.

Main Results:

• Lithium emeraldinate exhibits reversible redox chemistry with high charge delocalization.
• Achieved a high capacity of 230 mAh/g and energy density of 460 Wh/kg.
• Demonstrated excellent cycling stability with over 400 cycles at 1C rate and >99% coulombic efficiency.

Conclusions:

• Lithium emeraldinate is a promising high-capacity organic active material for non-aqueous Li batteries.
• The material's properties allow for thick composite electrodes with low conductive additive content.
• This discovery paves the way for stable, high-energy-density organic batteries.