Stellantis unveils IBIS battery system aimed at cheaper, lighter EVs

Stellantis has unveiled a new Integrated Battery System, or IBIS, that the automaker says could lower the upfront cost of electric vehicles by simplifying the powertrain and reducing weight. The company describes IBIS as a breakthrough that eliminates the need for separate charger and inverter components within many electric-vehicle architectures. The first fully functional IBIS-equipped battery electric vehicle is the Peugeot e-300 prototype, representing years of collaboration among Stellantis, technology firms, and the French government to advance electrified propulsion.

IBIS reimagines the electric powertrain by embedding inverter and on-board charging functionalities directly into the battery, regardless of chemistry or application. This architecture supports both alternating current (AC) and direct current (DC) charging and can deliver energy directly to the motor while also powering the vehicle’s 12-volt network and auxiliary systems. Traditionally, inverters are mounted near the motor or housed separately, and charging components are distributed throughout the vehicle to optimize weight distribution and cooling. By consolidating these functions into the battery, Stellantis says the system reduces mass and volume while maintaining or improving performance across different vehicle cadences.

The anticipated benefits are substantial. Stellantis reports a 10 percent improvement in energy efficiency on the WLTC cycle and a 15 percent power gain (172 kW versus 150 kW) with the same battery size. Weight is said to drop by about 40 kilograms, and up to 17 liters of internal volume could be freed, allowing for better aerodynamics, packaging, and design flexibility. Charging speed is also said to improve, with early results indicating a roughly 15 percent reduction in charging time on a 7 kW AC charger (about six hours versus seven) and about 10 percent energy savings overall. Maintenance could be simplified too, as servicing requirements shrink and the reduced need for extensive reconditioning supports potential second-life reuse for both automotive and stationary applications.

The Peugeot e-300 prototype marks a milestone for IBIS, serving as the first fully functional demonstration of an IBIS-equipped battery system in a production-intent chassis. Ned Curic, Stellantis’ chief engineering and technology officer, framed the development as a path to lighter, more efficient, and more cost-effective EVs. “By rethinking and simplifying the electric powertrain architecture, we are making it lighter, more efficient, and more cost-effective. These are the kinds of innovations that help us deliver better, more affordable EVs to our customers,” Curic said. The project has benefited from years of collaboration across Stellantis brands—Citroën, Fiat, Peugeot, Vauxhall—and a broader ecosystem of tech firms and public partners, including sustained government support from France.

Phase 2 of the IBIS program began in June 2025, with continued support from the French Government under France 2030. Stellantis says the current focus is real-world testing under representative driving conditions to validate performance and reliability before considering broader integration into production vehicles by the end of the decade. The company also highlights the potential applicability of IBIS beyond the automotive sector, pointing to rail, aerospace, marine, and data-center uses as part of a broader electrification strategy developed in collaboration with Saft, the battery subsidiary it co-commercializes.

In its broader planning, Stellantis notes that IBIS could help accelerate the adoption of electrified powertrains across multiple sectors by delivering a more compact, modular, and scalable architecture. The technology could enable faster development cycles and more flexible vehicle design, potentially lowering costs for a wide range of electric products. While the company has not announced a specific timing for mass production, officials emphasized that the work aligns with its strategy to offer affordable, high-performance EVs across its 14 brands, including Citroën, Fiat, Peugeot, and Vauxhall.

Stellantis’ IBIS initiative also reflects a longer-term industrial collaboration with Saft, its longtime partner in energy storage solutions, and underscores the automaker’s commitment to scalable electrification across transportation and energy systems. If successful in real-world testing, IBIS could influence future EV architectures by reducing the number of discrete powertrain components and enabling more compact, energy-dense battery packs. The approach may also simplify end-of-life handling and facilitate second-life applications, given the reduced reliance on specialized reconditioning for separate power electronics.

As the automotive sector continues to navigate cost pressures and supply-chain uncertainties, Stellantis’ IBIS program represents a strategic push toward deeper integration of battery systems and power electronics. The company has emphasized that the technology is designed to be agnostic to battery chemistry, which could help it adapt to evolving cell technologies while preserving the core advantage of consolidated power electronics and simplified vehicle packaging. Analysts will be watching closely to see whether the IBIS architecture translates into meaningful price reductions for consumers, improved vehicle range and performance, and streamlined manufacturing processes as the program moves from testing to potential scale.

Stellantis, whose brands span Citroën, Fiat, Peugeot, Vauxhall, and others, has indicated that the IBIS concept could unlock new design freedoms and cost efficiencies that might reshape the economics of EV adoption. While the path to mass production remains contingent on rigorous validation and supply-chain readiness, the company argues that the IBIS approach aligns with its broader goals of delivering affordable, capable, and sustainable mobility solutions at scale. If realized, the IBIS system could become a cornerstone of Stellantis’ strategy to bring down the total cost of ownership for electric vehicles while expanding the reach of electrification across multiple markets and industries.