Strain-coordination strategy enabling long-cycling all-solid-state lithium-sulfur batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• All-solid-state lithium-sulfur batteries promise high energy density and safety.
• High external operating pressure is currently required to prevent interface failures, limiting practical application.

Purpose of the Study:

• To develop a strain-coordination strategy to reduce the external pressure needed for stable all-solid-state lithium-sulfur battery operation.
• To mitigate mechano-electrochemical degradation at electrode interfaces.

Main Methods:

• Utilized a strain-coordination strategy with FeS2 positive and prelithiated Si negative electrodes.
• Modulated the Li-to-Si ratio to achieve a near-zero-strain effect, balancing electrode volume changes.
• Tested battery performance under reduced external pressure.

Main Results:

• Achieved a discharge capacity of 868.4 mAh g⁻¹ at 15 MPa.
• Demonstrated stable cycling with 4500 cycles at 1C and 140,000 cycles at 15C.
• Developed low-pressure pouch cells with stable cycling over 500 cycles at 15 MPa.

Conclusions:

• The strain-coordination strategy effectively reduces the required external pressure for stable all-solid-state lithium-sulfur battery operation.
• This approach mitigates mechano-electrochemical degradation, paving the way for practical applications.
• Offers a viable method for enhancing the safety and performance of next-generation batteries.