Surface engineering of inorganic solid-state electrolytes via interlayers strategy for developing long-cycling...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal batteries (LMBs) offer higher energy density than Li-ion batteries.
• Commercialization is hindered by lithium dendrite propagation in solid-state electrolytes.
• Developing stable inorganic solid-state electrolytes is crucial for LMB advancement.

Purpose of the Study:

• To engineer stable interfaces in LMBs using an Ag-coated LLZTO solid electrolyte and a silver-carbon interlayer.
• To investigate the mechanism of dendrite suppression using experimental and computational methods.
• To demonstrate the performance of an interfacially engineered LMB in a practical cell configuration.

Main Methods:

• Coating Li$_{6.4}$La$_{3}$Zr$_{1.7}$Ta$_{0.3}$O$_{12}$ (LLZTO) with silver.
• Incorporating a silver-carbon interlayer.
• Utilizing experimental measurements and computational modeling.
• Assembling a pouch cell with a lithium metal anode and a high-voltage cathode.

Main Results:

• Stable interfacially engineered lab-scale LMBs were produced.
• The interlayer strategy effectively regulated lithium stripping/plating.
• Dendrite penetration into the solid-state electrolyte was prevented.
• The LMB demonstrated 800 cycles at 1.6 mA/cm$^2$ and 25 $°$C with 85% capacity retention.
• An initial discharge capacity of approximately 3 mAh/cm$^2$ was achieved.

Conclusions:

• Interfacial engineering with Ag-coated LLZTO and a silver-carbon interlayer is a viable strategy for stable LMBs.
• This approach effectively suppresses lithium dendrite growth in solid-state electrolytes.
• The developed LMB shows promising performance for practical energy storage applications.