SK On, Factorial team up to scale solid-state EV batteries
SkimNews Take
Pairing a startup's solid-state chemistry with an established cell maker's factories shows the real bottleneck is manufacturing integration, not the technology itself—a pattern that has delayed every prior "breakthrough" battery chemistry from lab to line.
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- SK On and Factorial Energy signed an MOU on Wednesday to bring Factorial's FEST solid-state cell technology into SK On's global manufacturing network, assessing whether SK On's existing battery plants can support future solid-state production.
- Factorial CEO Siyu Huang said 'a battery breakthrough only matters if it can be manufactured at scale,' framing SK On's manufacturing footprint as critical to integrating solid-state tech into global production ecosystems.
- Factorial's 77Ah FEST cells achieved 375 Wh/kg over more than 600 cycles, with ultra-fast charging from 15% to 90% in 18 minutes and operation from -22°F to 113°F, per Stellantis.
- Factorial is testing FEST cells in North America via Stellantis' STLA Large platform in a Dodge Charger Daytona prototype and is also partnered with Mercedes-Benz, Hyundai, and Kia — Mercedes drove a modified EQS over 745 miles (1,200 km) on Factorial cells last fall.
- SK On supplies EV batteries to Hyundai Motor Group, Ford, and Volkswagen, with over 200 GWh of annual global production capacity including roughly 100 GWh in the US alone.
- The alliance follows Factorial's December partnership with South Korea's POSCO FUTURE M to develop materials for all-solid-state batteries.
Why it matters: Solid-state batteries have long posted impressive lab specs but stalled at the manufacturing stage. Pairing Factorial's validated 375 Wh/kg cells with SK On's 200+ GWh of annual global capacity — roughly 100 GWh of it in the US — gives the four major automakers Factorial is working with (Mercedes, Hyundai, Kia, Stellantis) a concrete factory floor for moving from prototype demos to mass production.
