Interface engineering enabling thin lithium metal electrodes down to 0.78 μm for garnet-type solid-state batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Thin lithium metal electrodes are crucial for high-energy-density solid-state batteries.
• Fabricating thin lithium electrodes is challenging due to lithium's properties.

Purpose of the Study:

• To develop a method for controllable engineering of thin lithium metal electrodes.
• To investigate the interfacial evolution mechanisms of lithium metal anodes.
• To enhance the performance and lifespan of quasi-solid-state lithium-metal batteries.

Main Methods:

• Treatment of Ta-doped Li7La3Zr2O12 (LLZTO) with trifluoromethanesulfonic acid to create a lithiophilic layer.
• Fabrication of thin lithium metal electrodes with controlled thicknesses (0.78 μm to 30 μm).
• Assembly and testing of quasi-solid-state lithium-metal batteries with optimized electrodes.

Main Results:

• Successfully controlled lithium metal electrode thickness from 0.78 μm to 30 μm.
• Achieved a 500-cycle lifespan in a quasi-solid-state battery with a 7.54 μm lithium electrode.
• Identified multi-dimensional compositional evolution and failure mechanisms in thin lithium electrodes.

Conclusions:

• The developed method facilitates the engineering of thin lithium metal electrodes, crucial for advanced batteries.
• Understanding interfacial evolution is key to optimizing lithium metal anode performance.
• This work paves the way for higher energy density and more stable solid-state batteries.