High-Conductivity Argyrodite Li₆PS₅Cl Solid Electrolytes Prepared via Optimized Sintering Processes for...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Solid-state electrolytes (SSEs) are crucial for developing safer and more efficient batteries.
• Lithium-ion conductivity in solid electrolytes is a key challenge for high-performance energy storage.
• Lithium sulfur batteries offer high theoretical energy density but require stable electrolytes.

Purpose of the Study:

• To synthesize and optimize Li6PS5Cl solid-state electrolytes (SSEs) via solid-state sintering.
• To investigate the impact of sintering temperature and duration on SSE properties.
• To evaluate the performance of Li6PS5Cl SSEs in all-solid-state lithium sulfur batteries (ASSLSBs).

Main Methods:

• Solid-state sintering method for Li6PS5Cl preparation.
• Systematic investigation of sintering parameters (temperature, duration).
• Electrochemical characterization including ionic conductivity and activation energy measurements.
• Assembly and testing of ASSLSBs using Li6PS5Cl SSE, nano-sulfur/carbon nanotube cathode, and Li-In anode.

Main Results:

• Optimized Li6PS5Cl SSE achieved high ionic conductivity of 3.15 × 10^-3 S cm^-1 at room temperature after sintering at 550 °C for only 10 minutes.
• The rapid sintering process proved more efficient compared to other reported synthesis methods.
• ASSLSBs demonstrated a high initial discharge capacity of 1850 mAh g^-1 and retained 1393 mAh g^-1 after 50 cycles.
• Near 100% Coulombic efficiency was maintained during galvanostatic cycling.

Conclusions:

• Li6PS5Cl is a highly promising solid-state electrolyte for all-solid-state lithium sulfur batteries.
• The optimized, rapid sintering method offers an efficient route for producing high-performance SSEs.
• The developed SSE facilitates high capacity and stable cycling in ASSLSBs, paving the way for advanced battery technologies.