Interphasial Chemistry Design for Seamless Lithium Deposition in Anode-Free Lithium Metal Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Anode-free lithium metal batteries (AFLMBs) offer high energy density and safety but suffer from unstable interfaces.
• Unstable interfaces lead to rapid depletion of active species and hinder practical application.

Purpose of the Study:

• To design an ultrathin ion-conducting membrane (ICM) for stabilizing the electrode-electrolyte interface in AFLMBs.
• To promote uniform lithium deposition and suppress dendrite formation.

Main Methods:

• Fabrication of an ultrathin ICM with rigid benzenesulfonimide anions and flexible lithiophilic groups.
• Characterization of the ICM's ion-conducting and electron-insulating properties.
• Assembly and testing of Li||Cu coin cells and AFLMBs with ICM-coated electrodes.

Main Results:

• The ICM facilitates uniform lateral lithium deposition and constructs stable anion-derived solid electrolyte interphases (SEI).
• Li||Cu coin cells with ICM achieved 99.82% Coulombic efficiency.
• AFLMBs with ICM-coated copper foil demonstrated an energy density of 495 Wh kg⁻¹ with 80.72% capacity retention after 100 cycles.

Conclusions:

• The designed ICM effectively enhances interfacial stability and lithium deposition in AFLMBs.
• This interfacial engineering strategy is crucial for developing high-performance and safe battery systems.
• The findings provide insights for practical applications of advanced battery technologies.