Rational Molecular Engineering via Electron Reconfiguration toward Robust Dual-Electrode/Electrolyte Interphases for...

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• High-energy-density lithium-metal batteries (LMBs) face challenges due to unstable electrode/electrolyte interphases (EEIs).
• Rational design of electrolyte additives is crucial for improving battery stability and performance.

Purpose of the Study:

• To investigate the effect of electron structure on additive properties and their impact on EEIs in LMBs.
• To propose an electron reconfiguration strategy for molecular engineering of additives for enhanced battery performance.

Main Methods:

• Analysis of electron structure, including intramolecular electron cloud density and delocalization, to understand additive mechanisms.
• Molecular engineering of sorbide nitrate (SN) additive to optimize coordination ability, energy levels, and interfacial properties.
• Electrochemical testing of modified electrolytes and pouch cells under various conditions (rate, temperature, cycling).

Main Results:

• The SN additive, designed via electron reconfiguration, effectively regulated solvation structure and improved oxidation stability.
• Formation of a stable, inorganic Li2O-rich solid electrolyte interface (SEI) facilitated uniform lithium deposition.
• Achieved high rate (10 C), low-temperature (-25 °C) performance, and long-term stability (2700 h) in Li||NCM811 pouch cells (4.5 Ah, 462 Wh/kg).

Conclusions:

• Rational molecular design based on electron structure regulation is a powerful strategy for enhancing electrolyte and interphase stability in LMBs.
• The proposed strategy offers a realistic reference for developing advanced electrolytes and practical lithium-metal batteries.