Integrated prelithiation and SEI engineering for high-performance silicon anodes in lithium-ion batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Improving the initial Coulombic efficiency (ICE) of silicon anodes is crucial for high-performance lithium-ion batteries.
• Conventional prelithiation methods are hindered by the low lithiation potential of crystalline silicon, limiting commercial viability.

Purpose of the Study:

• To investigate the effectiveness of lithium naphthalenide (Li-Naph) prelithiation on amorphous silicon anodes.
• To enhance the ICE and cycling stability of silicon anodes for next-generation batteries.

Main Methods:

• Utilized amorphous silicon anodes with a higher lithiation potential.
• Employed lithium naphthalenide (Li-Naph) for the prelithiation process.
• Conducted full-cell tests and pouch cell cycling performance evaluations.

Main Results:

• Achieved a significant ICE improvement from 74.8% to 97.2% in prelithiated amorphous silicon anodes.
• Demonstrated the formation of a robust solid electrolyte interphase (SEI).
• 27 mAh pouch cells retained 90.1% capacity after 800 cycles at 1 C, showing excellent stability and low-temperature performance.

Conclusions:

• Amorphous silicon anodes are effectively prelithiated using Li-Naph, overcoming limitations of crystalline silicon.
• The developed prelithiation strategy enhances anode stability and battery performance.
• This approach offers a scalable solution for advancing silicon anode technology in advanced lithium-ion batteries.