ProLogium and Rimac advance solid-state battery pack toward vehicle testing
ProLogium and Rimac Technology are finalizing their collaboration on next-generation batteries. At the Paris Auto Show, the partners will first display a pack mockup; functional hardware and a complete battery pack are set to follow in 2027, with initial vehicle tests planned for 2028.
The battery pack is still a mockup, with hardware expected to arrive in 2027.
Image: ProLogium
In Paris, the companies are presenting a conceptual mockup of the planned battery pack for the first time. The next development step is a functional battery segment, which will be used to test aspects such as thermal management, cell integration, and pack architecture.
The focus is on a cell-to-pack architecture for pouch cells. Rimac Technology describes it as a scalable integration solution for solid-state pouch cells. ProLogium provides its cell technology, while Rimac handles system development and integration.
This is explicitly not yet a production-ready battery pack. The companies are following a multi-phase development approach: building on the current mockup, they plan to first develop a functional battery module, then a fully operational battery pack, and finally integrate it into a vehicle.
The technical core of this cooperation lies at the system level. High energy densities at the cell level cannot be automatically translated into a lighter or more compact vehicle battery system. It is only through pack design, cooling, mechanical integration, and safety concepts that it can be determined which advantages truly benefit the vehicle.
Thermal management and cell integration in focus
Rimac is therefore exploring several integration options simultaneously. These include different approaches to thermal management, handling cell swelling, mechanical cell integration, and system design. Some concepts focus primarily on maximizing energy density while reducing space or weight, whereas others emphasize high performance. According to Rimac, the goal is to develop the battery as part of the vehicle itself: integrating components and functions together to reduce complexity and weight, while maintaining high charging speeds and power output.
If this approach proves successful at the vehicle level, manufacturers could utilize its weight advantages in various ways. With the same battery weight, this could result in more energy and thus greater range; a smaller and lighter battery pack while maintaining the same range; or hybrid solutions combining elements from both approaches.
ProLogium CEO Vincent Yang emphasizes that moving from the cell laboratory to the vehicle goes far beyond achieving good cell performance. Only by integrating it into a battery pack tailored to thermal, architectural, and mechanical requirements can the technology be made suitable for use in electric vehicles.
Functional segment by 2027, road tests in 2028
A timeline already exists for the subsequent development stages. The functional battery module currently in development is set to be showcased at CES 2027 according to Rimac Technology. A fully functional battery pack is planned for the second half of 2027.
Tests in vehicles and on public roads are scheduled to begin in the second half of 2028. This will allow the validation of individual integration concepts to progress gradually toward full deployment in vehicles. ProLogium refers to its latest cell generation as a “Superfluidized Inorganic Next-Generation Lithium Ceramic Battery.” The technology is designed to combine the advantages of solid-state and liquid electrolyte concepts while remaining scalable for industrial use.
The fact that ProLogium’s cell technology is already attracting interest from major manufacturers is also evident in its partnership with Mercedes-Benz. Since September 2026, Mercedes has been testing ProLogium’s Gen4 cells in its own and external testing facilities for their electrical, thermal, and safety-related properties. No decision has yet been made regarding their use in series production.
For the European supply chain, ProLogium’s expansion in France is also significant. A gigafactory is currently being built in Dunkirk, France, with the first phase designed to have an annual production capacity of 4 GWh. This capacity is set to be increased gradually by 2030. In the long term, the facility is planned to reach up to 44 GWh per year.
In 2024, ProLogium also opened a research and development center in Paris-Saclay to better integrate development with future production in France.
Rimac Technology is further expanding its role as a battery system supplier. The Croatian company is developing and producing a new high-voltage storage system for the updated i7 for BMW. There, Rimac combines cylindrical Gen6 cells in a 4695 format with a Gen5 module design; the finished battery systems are manufactured in Croatia and shipped to BMW’s Dingolfing plant.