Binder-Free, Self-Supporting, and Highly Conductive Sulfide Electrolytes Enabling Superior Anode Stability

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• All-solid-state batteries (ASSBs) promise higher energy density, power, and safety than conventional lithium-ion batteries.
• Developing solid electrolytes (SEs) with high ionic conductivity and stability is crucial for ASSB realization.

Purpose of the Study:

• To fabricate a robust sulfide-based glass SE layer using warm isostatic pressing (WIP).
• To integrate the SE into practical ASSB devices and evaluate their performance.

Main Methods:

• Fabrication of a binder-free sulfide-based glass SE layer via warm isostatic pressing (WIP).
• Incorporation of a glass-based supporting layer for mechanical enhancement.
• Integration of SE layers into 13 mAh-class laminated ASSBs with Ni-Co-Mn cathodes and graphite anodes.

Main Results:

• WIP process efficiency was enhanced by eliminating binders.
• The glass-based supporting layer provided mechanical strength and flexibility to the SE film.
• Assembled ASSBs retained ~80% capacity after 300 cycles at 25°C and 20 MPa stack pressure.

Conclusions:

• Binder-free SE fabrication using WIP is a viable strategy for ASSBs.
• The developed SE layers facilitate the creation of high-performance, stable ASSBs.
• This work paves the way for practical, high-performance ASSB implementation.