Uniform Fast-Kinetic Anode/Cathode Electrolyte Interphases Enable High Performance 3C Li-Metal Batteries with > 99.9%...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium metal batteries (LMBs) offer high energy density but suffer from unstable interfaces, hindering practical application.
• Anode dendrite growth and cathode degradation limit the performance and safety of LMBs in commercial electrolytes.

Purpose of the Study:

• To develop a dual-function electrolyte additive for enhancing the stability and performance of lithium metal batteries.
• To investigate the role of 4-fluoro-3-nitrophenylboronic acid in forming protective interphase layers on battery electrodes.

Main Methods:

• Introduction of 4-fluoro-3-nitrophenylboronic acid as an additive in lithium metal battery electrolytes.
• Electrochemical characterization including plating/stripping cycling and long-term cycle life testing at high rates (3C).
• Analysis of interphase layer composition (N-/F-rich) and morphology.

Main Results:

• The additive facilitated uniform N-/F-rich interphase layers on both anode and cathode.
• Li-metal electrodes showed significantly improved plating/stripping reversibility (>700 h) and coulombic efficiency (98.2%).
• LMBs demonstrated excellent cycle life with 99.9% capacity retention after 500 cycles at 3C and >99.9% coulombic efficiency.

Conclusions:

• 4-fluoro-3-nitrophenylboronic acid effectively stabilizes electrolyte interfaces in LMBs.
• The dual-function additive promotes uniform lithium deposition and suppresses electrolyte decomposition, crucial for fast-charging capabilities.
• Optimized electrolyte additives are vital for advancing high-performance, fast-charging lithium metal batteries.