Software Increasingly Defines the Powertrain
Ten years ago, transmissions were still seen as the ‘managers of the drive system’. Since then, the focus has shifted entirely. At the CTI Symposium Novi 2025, key topics included the diversity of electrified drive systems, new solutions such as Range-Extended Electric Vehicles, current challenges in electronics and battery development – and the Software-Defined Vehicle, which is also redefining drive development.
Sometimes, it can seem as though the Chinese automotive industry is inexorably outpacing Europe and North America. But in his introductory speech in Novi, CTI-USA Chairman Patrick Lindemann was far more upbeat. He invited his audience to see the bigger picture: Yes, over 30 million cars were sold in China in 2024, against just over 10 million in Europe and around 18 million in the USA (15 million of which were non-imports). But in Europe, the average car price was around $56,000, compared to $23,400 in China. At roughly $49,000, American vehicles were cheaper than in Europe – but in terms of total market sales, the USA led the field with $882 million, while China managed just $730 million, only slightly more than Europe. The bottom line: The US market is still the biggest. So as Lindemann put it: „Let’s discuss at this symposium, what the best drive technology is for the US market.” This much is clear: drive systems diversity will be around for a while, there is a new kid in town called REEV, and the Software-Defined Vehicle has already arrived. The focus of value creation is shifting – and that means excellent opportunities for the US industry.
Electrification: slow, but steady growth
Since these ‘best drive technologies’ will increasingly be electrified in North America, too, a review of the „Electric Vehicle Ecosystem” in the USA is a good place to start. In his presentation „US EV Industry Update”, Brent Gruber of J.D. Power said there was continuous growth in BEVs and HEVs, but PHEVs were still not really gaining traction. In 2025, HEVs accounted for 13.2% of all new registrations; BEVs achieved 9.5%, and PHEVs just 2.2%. Over the past three years, the number of BEV models in the market had risen from 27 to 62, most of them in the premium segment. Gruber asked why the EV market wasn’t growing faster. One reason, he said, was political uncertainty concerning tax incentives. But unless registrations grew faster, the US would miss its emissions targets. Charging infrastructures were another issue. Satisfaction levels were actually dropping here: 19 percent of EV drivers reported non-functioning charging stations, and the number of EVs was growing twice as fast as the number of charging stations. On the other hand, more than 4 in 5 people charged at home, while the average EV user drove less than 50 miles a day. Nevertheless, J.D. Power expects EVs to grow their market share from 2026 onwards, and predicts roughly 26% by 2030.
Range Extenders for the USA too?
REEVs (electric range extended vehicles) are very successful in China, alongside BEVs. Given the sheer size of the USA, could they make sense there too? At the symposium, the acronyms REEV and EREV were both used, and are interchangeable. Joe Tolkacz presented the Stellantis Ramcharger, calling it the „right vehicle at the right time” for the US market. The RAM 1500 Ramcharger is the first light truck in an REEV format, and the performance data are impressive. The independent electric drives on the front and rear axles deliver 250 and 248 kW respectively, while the V8 combustion engine supplies up to 202 kW to a generator with 202 kW peak and 130 kW continuous power. The battery capacity is 91.8 kWh, and Stellantis puts the total range at 690 miles. Being a light truck, the Ramcharger comes with an automatic transmission, plus a range of extra modes such as snow, trailer or off-road. Of particular interest to US customers is its V2X (Vehicle to X) compatibility, which means the Ramcharger can supply power to tools, other vehicles, and also to homes. This generator function is the main differentiator between the Ramcharger and a normal BEV. It can power a home for 11 to 22 days on a single tank of fuel, or even a whole neighborhood if refueling is an option – in theory, for as long as necessary.
At the symposium, opinions differed as to whether REEVs will really have a future or not. During the OEM panel discussion, Micky Bly, Stellantis, said a vehicle like the Ramcharger made sense because it could fully meet all consumers’ everyday needs. Stellantis currently offers two systems – the REEV for large body frame applications, and P2 PHEV solutions for models like the Jeep – and intends to pursue both options. Norman Peralta, GM, said PHEVs made sense for large cars and trucks since customers do not want to buy a BEV with today’s battery technology. Like his colleagues at Stellantis and GM, Thomas McCarthy said Ford wanted to give consumers a choice and would therefore keep supporting drivetrain diversity. Dante Boutell, Toyota, foresees a gradual shift from PHEV to REEV, but said BEV would ultimately prevail, especially if ranges continue to grow. During the Q&A session after his presentation, J.D. Power expert Brent Gruber made it quite clear that, in his opinion, REEVs, like PHEVs, were neither fish nor fowl – and were unlikely to take a sizable share of the market.
Electrification of Large and Work Trucks
The Truck Electrification Panel discussed the best drive system for large trucks. Jason Gies of Windrose thinks long-haul trucks will be fully electrified, too. He said Windrose was currently pursuing BEVs only, with ranges of up to 420 miles and a charging time of 38 minutes from 20-80% SOC. However, a high-performance charging infrastructure was „hypercritical.” By contrast, as Jerome Gregeois explained, Hyundai-Kia is pursuing three options: BEV, fuel cell, and EREV. Andreas Kammel of Traton also saw room for all options, depending on the application, but said, plug-in solutions were a niche, and BEV would also prevail in long-haul applications. Kevin Robinet of Scout said designing REEVs as a BEV architecture variant for smaller applications would make sense. „If BEV energy density quadruples, everything speaks for BEV – but when is that going to happen?” According to Ruidong Yang, BYD is also backing purely battery-electric drive systems for long-range trucks. He said REEVs made sense for some applications, but were technically more complex, and ultimately yielded less range per kilowatt.
As Chad Smith, Oshkosh, showed in his presentation „Advancing Powertrain Solutions for Work Trucks”, electrifying vocational and work trucks comes with its own set of requirements. Vocational trucks are commercial vehicles whose primary function is to „work.” Depending on the application, electrification levels vary greatly. Concrete mixers, for example, need to run continuously, so they are either HEVs, or ICE-only. Oshkosh also offers BEV garbage trucks with high recuperation levels, and a battery designed for the vehicle’s lifetime. Charging is not an issue here, he said, as operators had their own charging stations. Smith said Oshkosh also offered PHEV rescue and firefighting vehicles for airports. These had 28% better acceleration and sufficient range for normal daily use, and „German customers love them.” Military vehicles were a completely separate category; charging in an austere environment was impractical. That said, an HEV design made sense and could cut consumption by up to 30 percent, whereby the extra weight and complexity needed to be factored in. Smith finished up by mentioning several challenges in work truck electrification, including training and service for high-voltage applications, the availability of drive components, and ensuring the future availability of domestically produced batteries. Given the short production runs for work trucks, he said, the supply situation was more difficult than for large-scale manufacturers.
Battery Production as seen by a Volume Manufacturer
By contrast, Stellantis has to master large-scale production requirements on an international scale. Tim Grewe, Stellantis, talked about the challenges of „STLA Multi Energy Battery Systems & Industrialization”
in HEVs, PHEVs and BEVs. For example, Stellantis has to deal with the fact that European cars are smaller than American vehicles. Hence, the company portfolio includes three unibody platforms (small, medium, and large) with electric ranges of 300 to 500 miles, plus a body-on-frame platform for trucks with a range of up to 500 miles. The frame platform was just as suitable for ICE drives as for BEVs, FCEVs, xHEVs, and REEVs such as the Ramcharger. Grewe noted that Stellantis already offers 30 hybrid models in Europe under its Alfa Romeo, Fiat, Citroën, Peugeot, Opel, Jeep, and Lancia brands, with six more to follow in 2026. He said Stellantis tackled one major task over ten years ago, by standardizing battery production across all global locations. Using a cloth stretched across the stage, the speaker effectively demonstrated how delicate battery separators are and how critical even the slightest damage is. „You put a hole in it, and the lithium is going to find a way to cause trouble.” This applied to all batteries: hybrid batteries may have different and more frequent duty cycles, but the core requirements for production reliability were always the same. Each location needed be able to produce everything. Standardized processes were essential in order to meet customer needs quickly, globally, and promptly.
The Road to Software-Defined Vehicles
Lucid Motors is at the other end of the spectrum. It makes just two EV models – the Air and the Gravity – and follows a rigorous in-house development approach. In his lecture „Vehicle Efficiency Through Integrated Design of Drive Units and HV Battery”, Emid Diala described how Lucid developed most of its hardware and software in-house, from the battery system and electric motor to the power electronics and beyond. The company also designed its own development software. This enabled it to model and simulate all components and the overall system as early as possible. Before the first prototypes were built, developers even balanced battery properties (such as charging speed) and driving capability in the simulation. For Lucid Motors, its vehicles were the best examples of Software-Defined Vehicles (SDVs) – not just in terms of OTA software updates, but also in the high degree of hardware and software integration along the whole development chain. This would not have been possible using bought-in modules.
SDV in general is playing a growing role at CTI symposia, as illustrated by the presentation „Continuous Everything – Automotive in Transition to Becoming a Software Industry” by Florian Rohde, iProcess. Before becoming a consultant, Florian Rohde worked at Tesla on the Software-Defined Vehicle, „which wasn’t called that back then.” Up till now, he said, dealers sold and serviced cars. But today, you could retrofit features via software, and sometimes even sell them as a service. You could update the user interface, interact with customers, have a complete feedback loop, offer preventive maintenance, and avoid physical recalls. All of this required software-oriented processes and work structures. Using Tesla as his example, Rohde described how making changes to both software and software involved basing the work on schedules, as opposed to features. „If you have a software feature ready on time, it can go into the release train; if not, you have to stay where you are.” Traditional, component-based development also no longer made sense. Since the hardest aspect was integration at system level, everyone had to be in constant communication. It was vital to bring all the developers together as early as possible, and to test vehicle functions continuously and automatically throughout development. „When people are developing a new feature, allow them into the car”, the speaker explained. „Allow what is called feature branches.” In other words: develop features in an encapsulated environment, then integrate them back into the higher-level software tree.
From the developer viewpoint, Software-Defined Vehicle seems set to replace traditional component-based development rapidly – and not just in BEVs, as Florian Rohde noted. Feature-oriented development offers new possibilities, and new customer benefits. As Emid Diala put it: „An SDV doesn’t age during operation, it actually becomes more modern in terms of functionality.” Christine Thelesklaf, the Bosch representative on the Supplier Panel, added that in terms of brand differentiation, drive systems would matter less, while the way brands integrate their electronics and design their user interfaces would become more important.
Deep-dive contents and a new forum for innovative startups
The CTI Symposium Novi offered a comprehensive program of deep-dive presentations in addition to the plenary presentations and panel discussions. There were 53 in all, grouped under the following session headings: Electric and Hybrid Drives, E-Drive Components, E-Motors, Batteries, Thermal Management, Development Tools, AI & Testing, Commercial Vehicle Propulsion, Development Tools, Testing, and Lubrication.
In a new format that will be repeated at future events, seven startups introduced themselves briefly during the two days, and offered guided tours of their exhibition booths. For this new format, CTI has partnered with GAMIC, a non-profit organization with the mission to identify, mentor, and promote global startup innovations targeting the North American mobility market.
Dive Engineering Software offers a browser-based smoothed particle hydrodynamics software that enables virtual drivetrain lubrication and cooling analysis. EcoNova Tech has developed innovations using the Geneva mechanism or non-circular gears for uninterrupted shifting with EVs. eLeap-Power provides advanced power electronics solutions tailored for off-highway, light commercial, and passenger vehicle applications. Emil Motors is working on the next generation of electric motors, being entirely free of rare earth material. Limestone Engineering Services (LES) offer consultancy in areas like transmissions, ICE, BEV and specific fields like FE analysis, NVH, tribology etc. Marel Power Solutions is a power electronics company, focused on advancing electrified powertrain systems. Orbis Electric’s patented technology is a lightweight axial flux motor-generator with unrivaled power & configurability.
Software, Electronics, and Semiconductors are growing
Summing up, North America will continue to see a diverse range of drive concepts in years to come. Given the sheer distances involved, a one-size-fits-all solution seems unlikely to appear anytime soon. Will the relatively new vehicle category of REEVs gain traction in the USA too? We look forward to monitoring developments in this sector. One strong argument in their favor is their ability to serve as power generators, including in V2X applications. But as the discussion at Novi made clear, P2 PHEVs may still have their place wherever ICE hauling power has priority.
The trend towards software-defined vehicles is evident. SDV offers new service models, streamlined development processes, and tangible extra consumer benefits. How far will Software as a Service go? Will we eventually just sell functionality, not vehicles? Other areas whose growth will be matched by their coverage at future CTI Symposia include power electronics for electrified drives, where interesting advances are being made in the field of power semiconductors. What role can GaN play as an alternative to SiC, for example? Will highly efficient inverters trickle down to lower-cost applications? At the CTI Symposium Berlin (December 2 and 3, 2025, Estrel Hotel, Berlin), all this and more will be up for discussion.
