A dual-functional rare-earth yttrium-based electrolyte for stable lithium metal anodes

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Lithium metal anodes offer high energy density but suffer from dendrite growth and poor cycling stability.
• Developing stable solid electrolyte interphase (SEI) layers is crucial for safe and efficient lithium metal batteries.

Purpose of the Study:

• To design a novel rare-earth yttrium-based electrolyte system for lithium metal batteries.
• To investigate the formation of a robust and conductive inorganic-rich SEI film.
• To evaluate the efficacy of the designed electrolyte in suppressing lithium dendrite growth and stabilizing the anode.

Main Methods:

• Design and synthesis of a yttrium-based electrolyte system using yttrium trifluoromethanesulfonate (Y(OTf)3) and LiNO3.
• Analysis of the solvation structure and SEI film composition.
• Electrochemical testing of lithium metal cells to assess dendrite suppression and cycling stability.

Main Results:

• The designed electrolyte induces an anion-rich solvation structure.
• A Y-Li alloy layer is formed, leading to a robust and conductive inorganic-rich SEI film.
• Significant suppression of lithium dendrite growth and enhanced stability of the lithium metal anode were achieved.

Conclusions:

• The yttrium-based electrolyte system effectively forms a protective SEI layer.
• This approach offers a promising strategy for stabilizing lithium metal anodes.
• The study contributes to the advancement of high-performance and safe lithium metal batteries.