Unlocking Sulfide Solid-State Battery Longevity by the Paradigm of Dual-Functional Plastic Crystal

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Batteries

Background:

• Sulfide solid electrolytes offer high safety and energy density for all-solid-state batteries.
• Interface instability between oxide cathodes and solid electrolytes hinders battery performance.
• Plastic crystals, known for elasticity and conductivity, are promising for overcoming interface issues.

Purpose of the Study:

• To enhance the performance of sulfide-based solid-state batteries by addressing cathode interface challenges.
• To investigate the use of plastic crystals as a coating for nickel-rich oxide cathodes.
• To improve electrochemical and mechanical stability at the cathode-electrolyte interface.

Main Methods:

• Coating nickel-rich oxide cathodes with ionically conductive plastic crystals.
• Utilizing plastically deformed succinonitrile as a metal ion ligand for mechanical stability and interfacial conduction.
• Incorporating LiDFOB to enhance ionic conductivity and form a stable cathode electrolyte interphase (CEI).

Main Results:

• Achieved remarkable long-term cycling performance, retaining 80% capacity after 1529 cycles.
• Demonstrated sustained stability at a high areal capacity density of 3.53 mA h cm⁻².
• Synergistic effects of plastic crystals and LiDFOB improved interfacial properties.

Conclusions:

• Plastic crystal coatings offer a facile approach to enhance sulfide solid-state battery performance.
• The combination of electrochemical stability and mechanical plasticity is key for durable solid-state batteries.
• This strategy paves the way for developing practical, long-lasting solid-state batteries.