Hydrogen-Bond-Networked Robust Binder Enabling Long-Cycling Sulfide-Based All-Solid-State Lithium Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Scalable manufacturing of sulfide-based all-solid-state lithium batteries (ASSBs) via wet processing requires binders compatible with low-polarity solvents and sulfides.
• Existing binders struggle to achieve thin sulfide solid electrolyte (SSE) films (≤ 30 µm) and high-loading composite cathodes (≥ 30 mg cm⁻²).

Purpose of the Study:

• To develop a novel binder enabling efficient wet processing for practical ASSBs.
• To improve the mechanical integrity and processability of SSE films and composite cathodes.

Main Methods:

• Design of a dynamic hydrogen bonding-empowered robust polymer (PNO) binder utilizing soft-hard segment synergism.
• Incorporation of polybutadiene soft segments for processability and carbamate-containing hard segments for mechanical strength via dynamic hydrogen bonding.
• Fabrication and testing of ASSBs with PNO binder-based cathodes and SSE films.

Main Results:

• The PNO binder facilitates the formation of thin SSE films and high-loading composite cathodes.
• Dynamic hydrogen bonding in PNO enhances mechanical strength and stress dissipation, ensuring structural stability during processing and cycling.
• ASSBs assembled with PNO binder demonstrated outstanding cycling stability, outperforming recently reported sulfide-based ASSBs.

Conclusions:

• The soft-hard segment synergism binder design strategy overcomes key bottlenecks in wet processing of ASSBs.
• PNO binder is conducive to accelerating the scale-up production of advanced sulfide-based ASSBs.
• This approach offers a pathway for developing high-performance, manufacturable solid-state batteries.