by Andrea Ingenito, Sufu Liu (CSEM)
Share
by Andrea Ingenito, Sufu Liu (CSEM)
January 27, 2025
Share

Silicon is widely recognised as one of the most promising alternatives to graphite anodes in high-energy-density batteries. With its high theoretical capacity, silicon offers the potential to revolutionise energy storage. However, its practical application has been hindered by significant challenges, including:
- Huge volume expansion during cycling.
- Unstable electrode interphase formation.
- Short cycle life, which limits long-term performance.
To address these issues, one of PHOENIX partners, CSEM, has developed an innovative in-situ polymer electrolyte with self-healing properties. This solution stabilises the electrode interphase and effectively mitigates the volume expansion of silicon material during battery operation.
How it works
The technology relies on a specially designed liquid precursor solution containing:
- A monomer and cross-linker for polymer formation.
- Li salt for ion conductivity.
- An initiator to start the polymerisation process.
The solution is injected into the dry cell, where it wets the internal components. Heating the cell initiates radical polymerisation, forming an in-situ self-healing polymer electrolyte. This electrolyte dynamically stabilises the silicon-based anode during operation, enhancing its overall performance.
Key benefits
- Improved stability: the self-healing properties help maintain a stable electrode interphase.
- Volume change mitigation: the polymer electrolyte restrains the significant volume expansion of silicon material.
- Enhanced performance: the 200 mAh SiOx-graphite//NMC pouch cell demonstrated:
- Excellent rate performance.
- Long-term capacity retention.
This approach represents a significant advancement in silicon-based battery technology, paving the way for more efficient and durable batteries. With improved performance and stability, silicon anodes are moving closer to becoming a practical solution for next-generation energy storage systems.

Figures: (a) The self-healing property test of the designed thermally triggered polymer electrolyte (b) The long-term cycling performance of the 200 mAh SiOx-graphite//NMC pouch cell with the self-healing polymer electrolyte.