Supremely elastic gel polymer electrolyte enables a reliable electrode structure for silicon-based anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Silicon-based anodes offer high capacity for lithium-ion batteries but suffer from structural degradation due to significant volume changes during cycling.
• This degradation leads to particle displacement, electrode collapse, and reduced battery lifespan, hindering their commercial application.

Purpose of the Study:

• To develop a stable anode material for next-generation lithium-ion batteries.
• To overcome the challenges of volume expansion and structural instability in silicon-based anodes.
• To achieve long-term cycling stability and high performance in silicon monoxide (SiO) anodes.

Main Methods:

• Development of a supremely elastic gel polymer electrolyte using a unique copolymer with soft ether and hard cyclic ring domains.
• Integration of the elastic gel polymer electrolyte with silicon monoxide anodes.
• Electrochemical testing of SiO|LiNi_0.5Co_0.2Mn_0.3O₂ cells to evaluate cycling stability, capacity retention, and Coulombic efficiency.

Main Results:

• The elastic gel polymer electrolyte effectively mitigated the displacement of SiO particles and reduced electrode volume expansion.
• Electrode cracking damage was alleviated, leading to improved structural integrity.
• The SiO anode demonstrated 70.0% capacity retention over 350 cycles, with a commercial-level reversible capacity of 3.0 mAh cm^-2 and an average Coulombic efficiency of 99.9%.

Conclusions:

• The developed elastic gel polymer electrolyte is a promising solution for stabilizing silicon monoxide anodes in lithium-ion batteries.
• This approach enables long-term, stable cycling performance, paving the way for high-capacity silicon-based battery technologies.
• The findings contribute to the advancement of next-generation energy storage solutions with enhanced durability and efficiency.