Mitigating Electron Leakage of Solid Electrolyte Interface for Stable Sodium-Ion Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Interfacial stability is crucial for sodium ion battery (SIB) longevity and safety.
• Continuous solid-electrolyte interphase (SEI) growth degrades interfacial stability.
• SEI growth is linked to electron leakage, a factor rarely addressed for suppression.

Purpose of the Study:

• To investigate strategies for suppressing SEI growth by mitigating electron leakage.
• To develop SEI layers with distinct growth behaviors using an additive strategy.
• To correlate SEI physicochemical and electronic properties with suppressed growth and improved battery performance.

Main Methods:

• Fabrication of two distinct SEI layers via an additive strategy.
• Comprehensive characterization of SEI physicochemical features (morphology, composition).
• Investigation of SEI electronic properties (LUMO level, band gap, electron work function) using experimental and computational methods.

Main Results:

• The SEI layer with suppressed growth exhibited a low electron driving force.
• This suppressed SEI layer demonstrated high electron insulation ability.
• Mitigated electron leakage effectively restrained continuous SEI growth.

Conclusions:

• The developed additive strategy successfully suppressed SEI growth by controlling electron leakage.
• Enhanced electron insulation of the SEI layer is key to improved interfacial stability.
• This approach leads to enhanced electrochemical performance in sodium ion batteries.