Solvation Sheath Engineering by Multivalent Cations Enabling Multifunctional SEI for Fast-Charging Lithium-Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Fast charging of lithium-metal batteries is crucial for high energy density.
• Preventing lithium dendrite formation requires a solid electrolyte interphase with fast ion transport and uniform nucleation.
• Facile construction of such an interphase remains a significant challenge.

Purpose of the Study:

• To develop a facile method for constructing an ideal solid electrolyte interphase for lithium-metal batteries.
• To enhance the fast-charging capability and cycle stability of lithium-metal batteries.

Main Methods:

• Tuning the Li+ solvation structure by introducing lithium nitrate (LiNO3) and aluminum ethoxide.
• Utilizing the high charge of Al3+ and the lithiophilic nature of Al metal.
• Simultaneously generating fast ionic conductor and lithiophilic sites.

Main Results:

• Facilitated uniform and chunky deposition of lithium metal, even at high current densities.
• Achieved over 99% Coulombic efficiency in Li||Cu cells.
• Demonstrated remarkable capacity retention of 94.5% at 4 C in Li||LiFePO4 full cells, significantly outperforming the base electrolyte (46.1%).

Conclusions:

• The proposed method effectively creates an ideal solid electrolyte interphase for fast charging.
• This approach significantly improves the performance and cycle life of lithium-metal batteries.
• The strategy offers a promising pathway for developing next-generation high-performance batteries.