EQS prototype drove 1,205 km from Germany to Sweden without recharging, retaining 137 km range.
Battery system co-developed with HPP and Factorial Energy using FEST-based solid-state technology.
Mercedes-Benz targets solid-state integration in production vehicles by end of the decade.
A prototype Mercedes-Benz EQS equipped with a solid-state battery completed a 1,205-kilometre journey from Stuttgart, Germany to Malmö, Sweden without recharging, in a real-world test of next-generation battery technology. The vehicle retained a remaining range of 137 kilometres upon arrival.
2025 Mercedes-Benz EQS with solid-state battery | Photo: Mercedes-BenzConducted in late August, the test formed part of the company’s ongoing validation program for solid-state batteries. The route traversed three countries, following highways A7 and E20 through Germany and Denmark, before entering Sweden, without relying on ferry transport. Mercedes-Benz used its Electric Intelligence system to determine the optimal path, accounting for topography, traffic conditions, and energy demands for climate control.
The battery system used in the test vehicle was developed in collaboration with Mercedes-AMG High Performance Powertrains, a unit best known for its Formula 1 expertise. The battery cells were supplied by U.S.-based Factorial Energy and use FEST (Factorial Electrolyte System Technology).
2025 Mercedes-Benz EQS with solid-state battery | Photo: Mercedes-BenzThe system integrates pneumatic actuators to manage volume changes during charging cycles, thereby maintaining consistent contact pressure. According to the company, usable energy content was increased by 25% compared to the standard EQS battery, without increasing its size or weight. The prototype also employs a passive airflow cooling system to improve energy efficiency.
The demonstration follows the company’s February announcement of road testing for the technology and builds upon the performance of its Vision EQXX, which previously completed a 1,202-kilometre journey. Mercedes-Benz’s goal is to integrate solid-state battery technology into series production vehicles by the end of the decade.
Testing of the battery continues at company facilities in Stuttgart-Untertürkheim and Sindelfingen, with the long-distance drive representing a key milestone in validation efforts designed to evaluate battery performance under various real-world conditions.
