Dodge Charger maker road-tests solid-state EV battery hitting 90% charge in 18 minutes

Stellantis has integrated Factorial Energy’s solid-state battery cells into a Dodge Charger Daytona development vehicle and begun road testing the technology, marking a key step toward bringing solid-state batteries into production vehicles.
The milestone is the first time Factorial’s FEST (Factorial Electrolyte System Technology) solid-state cells have been installed in a Stellantis vehicle. The companies will now evaluate battery performance, reliability, and safety under real-world driving and charging conditions.
The development follows laboratory validation completed in 2025, when Stellantis and Factorial demonstrated automotive-scale FEST cells with an energy density of 375 Wh/kg. The cells also achieved charging from 15 percent to 90 percent in 18 minutes and operated across temperatures ranging from -22 °F to 113 °F.
Moving from laboratory testing to an on-road vehicle required engineers to redesign parts of the battery system. Stellantis said it developed a patented mechanical architecture that allows the solid-state cells to fit within an existing battery pack while maximizing performance.
From lab to road
Engineers also modified battery controls and pack design to meet automotive requirements for durability and safety. According to the companies, these changes were needed to ensure consistent performance under a range of driving and charging conditions.
The battery pack is based on Stellantis’ STLA Large platform and serves as the first vehicle in a previously announced multi-stage development program.
“Battery development is a balancing act. It’s not enough to optimize a single metric. We need a system that delivers real benefits in a real vehicle,” said Ned Curic, Stellantis Chief Engineering and Technology Officer.
“This milestone shows we are bringing solid-state batteries closer to our customers with the potential for longer range, faster charging, and lower costs. Just as important, FEST’s strong compatibility with lithium-ion manufacturing processes gives us a critical path to scale this technology.”
Solid-state batteries replace the liquid electrolyte used in conventional lithium-ion batteries with a solid material. The technology is expected to improve energy density, increase safety, and reduce charging times. However, scaling production and integrating the cells into vehicles have remained major challenges for automakers and battery developers.
Scaling battery technology
With the battery now installed in a working vehicle, Stellantis and Factorial have launched a testing and calibration program to gather performance data from real-world operation.
The companies said the program will evaluate charging behavior, vehicle safety, and long-term reliability. The results will also help refine battery management systems and pack-level controls before any future commercial deployment.
“We are deeply honored to work alongside Stellantis, one of the world’s great mass-market automakers, on this STLA Large-based development car,” said Siyu Huang, CEO of Factorial.
“What we have built together, from cell chemistry to pack architecture to enable real-world road testing, is exactly the kind of deep, full-stack collaboration that solid-state has always required.”
Factorial, which is backed by Stellantis, Mercedes-Benz, Hyundai and Kia, is among several companies racing to commercialize solid-state batteries. The latest milestone moves its technology beyond cell-level testing and into vehicle validation, a critical stage before potential mass-market adoption.