A Doping Protonation Strategy for the Highly Elastic Foam-Structured Hydrogels to Boost the Performance of SiO Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Silicon oxide (SiO) is a high-capacity anode material for lithium-ion batteries (LIBs).
• Its practical application is limited by poor electrical conductivity and volume expansion during cycling.
• Developing effective binders is crucial to address these challenges.

Purpose of the Study:

• To design a novel hydrogel binder for SiO anodes.
• To improve the electrochemical performance and stability of LIBs using SiO anodes.
• To investigate the structure-property relationships of the new binder.

Main Methods:

• Synthesis of PAA@PANI@SA (N-PPS) hydrogels using poly(acrylic acid) (PAA) and polyaniline (PANI).
• Fabrication of SiO anodes utilizing the N-PPS hydrogel binder.
• Electrochemical testing including cycling performance and stability analysis.
• Molecular dynamics simulations to study ion transport and conductivity.

Main Results:

• The N-PPS hydrogel exhibits an entangled chain-linked foam structure with high mechanical strength and self-healing properties.
• The N-PPS binder significantly enhances the cycling stability of SiO anodes, retaining 1200 mAh g^-1 after 300 cycles.
• Molecular dynamics simulations reveal excellent ion transport properties (D_Li⁺ = 7.2 × 10^-17) and enhanced conductivity (2.12 × 10^-3 S cm^-1).

Conclusions:

• The N-PPS hydrogel binder effectively addresses the limitations of SiO anodes in LIBs.
• The unique structure of N-PPS facilitates lithium-ion diffusion, improving battery performance.
• This work demonstrates the promising potential of N-PPS as a binder for advanced energy storage applications.