Sionic Energy has unveiled breakthrough joint results with Group14 Technologies demonstrating industry-leading high-temperature stability for 100% silicon-carbon anodes in high-energy lithium-ion cells.
The findings demonstrate a viable silicon-dominant path for electric vehicles, aerospace and eVTOL platforms, and compact electronics requiring long life and high-temperature resilience.
By combining Group14’s SCC55 silicon-carbon anode material with Sionic’s Rapid Integration Silicon Platform—featuring a 100% silicon-carbon anode and enhanced electrolyte—the companies claim a new benchmark for silicon battery performance, paving the way for wider adoption in transportation, consumer electronics, and aviation.
Testing of Sionic’s platform with SCC55 in 4-Ah, 10-Ah, and 20-Ah pouch cells under electrolyte-lean conditions with NMC 83 cathodes showed stable 1C/-1C cycling at 45°C and retention of more than 70% of room-temperature cycle life. Storage tests at 45°C and 60°C revealed significantly suppressed gas generation and lower impedance growth, pointing to extended calendar life over conventional chemistries.
“Our Rapid Integration Silicon Platform delivers up to a 50% jump in performance while dropping right into industry standard equipment with no complexity,” said Ed Williams, President and CEO of Sionic Energy.
Sionic’s graphite-free platform achieves market-leading energy density when paired with SCC55—up to 400Wh/kg—alongside exceptional cycle life of up to 1,200+ cycles and high-rate performance in formats compatible with existing manufacturing processes.
“I’ve spent years watching the industry chase silicon’s promise and hit the walls of complexity, cost, development time, and narrow performance. That's why I'm proud to share this Sionic benchmark and the Group14 partnership that breaks through those walls and accelerates silicon's broad market adoption,” Williams said. “Our Rapid Integration Silicon Platform delivers up to a 50% jump in performance while dropping right into industry standard equipment with no complexity: no pre-lithiation, no external compression, no extensive cell design efforts, and industry standard cell formats.”
Group14’s SCC55 uses a porous hard-carbon scaffold to manage expansion and side reactions, preserving silicon integrity over long lifetimes. Already proven at commercial volumes, SCC55 shows cycle-life data in the 1,500–3,000 cycle range.
“This benchmark is a powerful validation that silicon batteries are market-ready,” said Rick Luebbe, CEO and Co-Founder of Group14 Technologies.
“Customers want true drop-in silicon-carbon anodes that deliver up to 50% higher energy density, dramatically faster charging, and robust lifetime across extreme temperatures. These latest results with 100% SCC55 show that with world-class materials and strong cell engineering, we can meet those expectations at scale, today.”
