Silicon-rich cells retain 83% capacity after 1,000 cycles, Fraunhofer says

Fraunhofer ISE tested 25-Ah pouch cells with silicon-rich anodes under its StrOboBatt project: at 1,000 kPa contact pressure they kept over 83% of capacity after more than 1,000 full cycles. Energy density reached 280 Wh/kg, with about 330 Wh/kg projected for an optimized format.

• 25-Ah cells use a silicon-carbon composite making up 51% of anode active material
• Demonstrated 280 Wh/kg; optimized pouch format projected at ~330 Wh/kg
• Capacity fade was greater at 300 kPa than at 1,000 kPa contact pressure
• Anode specific capacity above 1,000 mAh/g and areal capacity over 5 mAh/cm²