Range anxiety is history! Get up to speed here on the hottest topics in electric powertrains

Ranges of over 600 km, ultra-high-speed charging … recent BEVs have long since proven how practical they are – and tomorrow’s models will go further still. To solve today’s pres-sing challenges, manufacturers need three things: expertise, innovative technologies, and courage.

CTI Symposium Germany 2025: see for yourself how e-mobility is progressing!

Fourteen deep-dive sessions with over 80 expert presentations await you in Berlin. Two deep-dive sessions are dedicated entirely to the latest developments in powertrains. How much potential do axial flux motors, range-extender drives and high-speed motors have? Will powertrains soon be a magnet-free zone? What’s the most compelling alternative to the permanent magnet synchronous motors that still prevail today? Find out more about our fascinating symposium program below.

Manufacturers present their highlights: From range extender solutions to long-haul trucks

The new Nissan LEAF: What makes the 3rd generation of this bestseller so convincing?

When Nissan launched the LEAF in 2010, it was the world’s first mass-produced electric vehicle. Up until late 2019, it was also the world’s best-selling BEV. In June 2025, the com-pany unveiled its third-generation LEAF. In Berlin, Shunsuke Shigemoto (Nissan) will describe the new model’s key innovations. These include a new battery system, a compact integrated drive unit, and a bidirectional onboard charger. A ‘big module’ increases the battery’s capacity density and charging performance. The integrated 3-in-1 drive unit com-bines the inverter, motor, and transmission in a single housing, for improved rigidity and a compact package. Benefits include improved NVH performance with unprecedented smoothness, and higher efficiency for greater range. The new model ships with a new bidi-rectional onboard charger as standard – ideal for charging e-bikes or powering tools. In fu-ture, the LEAF will also permit vehicle-to-grid backfeeding.

The electric axle of the Mercedes-Benz eActros600. Find out what powers the International Truck of the Year 2025.

After Bertram Wunderlich (Daimler Truck)’s presentation, you’ll know exactly why the eAcross600 deserves its Truck of the Year Award. Having already developed an e-axle for heavy-duty distribution traffic, Daimler Truck is now expanding its portfolio with an e-axle for long-haul applications. This is one of the next steps towards emission-free freight transport and the decarbonization of the industry.

In part one of his presentation, Bertram Wunderlich will explain the concept and design of the new eAxle. He will offer insights into possible concepts and their advantages and disadvantages, and will explore ideas for increasing efficiency. Part two will examine the technical implementation, the main components, and their respective functions. Starting with the inverter, the speaker will cover the entire eDrive train, including the motor, housing, transmission, axle, and cooling system. Finally, he will discuss the application of the unit in the vehicle, and the challenges it faces in a global vehicle portfolio.

Li Auto’s new Range Extender Powertrain – the next chapter in a successful story

Li Auto is a highly successful specialist manufacturer of REEVs (Range Extender Electric Vehicles) in the Chinese market. In Berlin, Dr. Qiang Liu (Li Auto) will describe the sys-tem architecture and key technologies of his company’s 3rd-generation range extender powertrain. His presentation will illustrate Li Auto’s systematic vehicle-to-chip technical ap-proach, which began by deriving system performance requirements and boundary condi-tions from the vehicle performance. On the component level, the speaker will explain how the electrical magnetic design of the PSM motor enhances generator efficiency, and will describe the key technologies of a high power density ASM traction motor. Dr. Qiang Liu will also cover solutions for power electronics and semiconductor technology (including the software structure) in detail, right down to the size and number of high-voltage IGBT and diode chips. Finally, the speaker will discuss how the platform solution can be scaled and extended for use in different vehicle segments.

Developers have a new favorite: electrically excited synchronous machines (EESMs), including high-speed brushless versions

The vast majority of EVs are still powered by permanent magnet synchronous motors (PMSMs). But driven by sustainability concerns and supply chain risks, the call for magnet-free electric motors is growing louder, and electrically excited synchronous machines (EESMs) could be the solution. Either way, high-speed motors are definitely trending.

The study presented by Brice Lecole (Valeo) will examine the significant system-level benefits of a high-speed e-axle architecture for EVs. The focus rests on ‘upspeeding’, which boosts power density via higher rpm at lower torque. Using advanced electric motor technology, a high-speed carbon-clad rotor was integrated into a standard two-step high-

ratio reduction gearbox. An optimal top speed of 22 – 25k RPM was determined for the tar-geted power range. As the study results show, higher motor speeds offer significant poten-tial for downsizing the electric motor. This in turn can reduce material consumption, motor manufacturing costs, and the overall mass of the e-axle.

In Berlin, Martin Burgbacher (AAM) will go one step further with a solution that involves motor speeds of 30,000 rpm. Together with a highly integrated propulsion inverter, this can substantially increase the power density of the motor and inverter to over 25 kW/liter. These targets were envisioned for a 650Vdc EDU application rated at over 200kW for both primary and secondary drive applications. As the speaker will explain, the 30k RPM motor cuts design costs by reducing the amount of copper and magnetic lamination materials re-quired. The stator is encapsulated with a thermally conductive plastic material, while the high-speed rotor was designed using copper bars for high efficiency. The transmission u-ses a high reduction ratio of 23:1, which translates to 4500Nm of torque at the axle. A highly integrated 650Vdc ring inverter is tightly integrated into the inner diameter of the stator end turns, and provides a max phase current of 350Arms.

Valeo and MAHLE have joined forces to develop an innovative, magnet-free electric axle system for high-end EVs with peak power ranging from 220 kW to 350 kW. As Camelia Jivan (Valeo) and Thomas Hennings (Mahle) will explain, the aim of this cutting-edge technology is to revolutionize the performance and efficiency of magnet-free electric mo-tors (EESMs). The project combines Valeo’s expertise in electric motors, high-efficiency inverters (SiC and switching cell technologies) and associated motor control with MAHLE’s expertise in magnet-free rotors and its MAHLE Contactless Transmitter (MCT) technology. In tests, the fully integrated brushless motors demonstrated efficiency levels of >96%, con-tinuous peak power in excess of 60%, and a 40% smaller carbon footprint than PMSMs of the same power. In their presentation, the speakers will describe the key design decisions, compare brushless and brush motors, and emphasise that brushless motors are the main alternative to PMSM.

Axial flux machines: more than just a niche product?

Radial flux motors are inherently more efficient than their axial flux counterparts, but may need higher gear ratios to deliver the same amount of torque to the axle. Axial flux ma-chines promise high power density – but does that still apply in combination with a trans-mission? In Berlin, Kristoffer Nilsson (Alvier Mechatronics) will offer a comprehensive comparison of axial and radial flux topologies. His simulation study compares two axial flux machines with two radial flux machines, across two types of transmissions: a standard two-layshaft design, and a coaxial planetary design. The study evaluates these combina-tions over standard WLTC driving cycles, as well as for acceleration capability, on two dif-ferent vehicle specifications. How did the candidates fare, and what conclusions can we draw? In Berlin, Kristoffer Nilsson will reveal all this and more.

Electrically excited synchronous motors (EESMs) are a promising alternative to permanent magnet synchronous motors (PMSMs), whose downsides include supply chain risks, costs, and sustainability. In Berlin, Dr. Philippe Farah (Yeesma) will show how the ad-vantages of EESMs can be perfectly combined with those of axial motors. YEESMA is cur-rently developing an innovative Electrically Excited Axial Flux solution. The dual rotor, sin-gle stator approach helps solve packaging and performance challenges by delivering up to 20% more torque volumetric density, cost savings of over 50%, and a 60% higher sustain-ability index score. Dr. Philippe Farah will also describe how novel manufacturing solutions are helping Yeesma to reduce the challenges of assembling axial flux motors. The inverter phase current has also been significantly reduced, contributing to the 50% cost savings described above. The presentation will examine applications ranging from 10 kW to 350 kW in detail.

CTI Symposium Berlin: Book now for this ultra-high performance density event!

Come and join us on December 2nd and 3rd, 2025, when decision-makers and experts provide cutting-edge insights into the topics that are driving the industry. Choose your per-sonal highlights from a top-notch program featuring 14 deep-dive sessions and over 80 lectures, as well as plenary sessions and discussions. Get talking to exhibitors at the CTI EXPO, and to young innovators in the Startup Area. Then in the evening, make invaluable new contacts in the relaxing atmosphere of our CTI Networking Night.

Welcome to Berlin!

Further Development of the Limestone Engineering Continuously Variable Transmission (CVT)

James Kalkstein, PE, Chief Engineering Officer and Principal, Limestone Engineering Services, LLC
Limestone Engineering Services, LLC (LES)

Limestone Engineering Services, LLC (LES) has continued development of our unique and patented CVT under patent #11,371,592. The development has moved from the Research Proof-of-Concept Prototype as shown in the patent disclosure to an engineered Development Prototype (DP#1) shown in the figure below (Figure#1).

*Figure #1: Development Prototype #1 (DP#1) on Test Bench Setup

The DP#1 is constructed from 3D-Printed Hyper-PLA material. This material is rated at a tensile strength that is approximately 20 % of the strength of typical aluminum. Therefore DP#1 has a limited torque capacity when compared to a full-production metallic unit. However, the belt is a production-ready 5Mx15mm cog-type timing belt with a torque capacity of approximately 95 N-M (70 lb-ft). The gear-ratio span for the DP#1 unit is setup to be from approximately 1.2:1 to 0.8:1.

The ratio-change actuator in the DP#1 uses a threaded rod to actuate the devices that changes the ratio. However, the patent includes actuation devices of any kind, including but not limited to; 1) electromechanical; 2) hydraulic, or 3) pneumatic.

Please note that:

1. Virtually any timing belt width and pitch is possible allowing for virtually any torque capacity and;
2. Ratio spans are a function of the physical size of the unit and can be increased or reduced by design.

Several design iterations have been made for the idler pulley arrangements. All proved to be satisfactory, and the final choice should be based on the final design chosen.

Testing:

This DP#1 has been tested on a test bench using a simple Prony-Brake absorber system. The test-applied torque/speed capacity is approximately 20 N-M (15 lb-ft) maximum at approximately 1,000 rpm. Please note that this is using non-metallic Hyper-PLA material and not aluminum or other metallic material components. Additionally, the input drive device was limited to these values (20 N-M (15 lb-ft) @ 1,000 rpm). We believe that this testing level was very close to the ultimate-strength of the component design using this Hyper-PLA material. However, a material change (e.g … to aluminum or steel) should bring the capability to the level of the belt ultimate-strength without any additional design changes.

Cost and Supply Chain:

The supply chain for the DP#1 requires no special components for belts, fasteners, or bearings (rotational, thrust and linear). They are all Commercial Off-The-Shelf (COTS) items. However, the main operating components are specially designed for this application. We have investigated small batch fabrication for a small number (~ 5 units) of DP#1 for full-power test-bench testing. We estimate that these units would cost approximately $500 − $750 per unit to produce, not including assembly labor and special assembly fixtures. We estimate that in series-production, the cost would fall by, at a minimum, one order of magnitude , but could have even greater reductions in larger volumes.

Revolutionizing Electric Mobility with Emil Motors’ SAM Technology

Maximilian Guettinger, CEO & Co-Founder, Emil Motors

The electric vehicle (EV) industry is experiencing unprecedented growth, driven by global demand for sustainable transportation. Yet, this momentum faces hurdles: the reliance on rare-earth magnets − primarily sourced from China − introduces supply chain risks, compounded by potential tariffs that could disrupt production and escalate costs. Amid these challenges, Emil Motors emerges as a game-changer with its Segmented Axial Flux Asynchronous Motor (SAM) technology. This magnet-free innovation not only sidesteps geopolitical and environmental concerns but also delivers superior performance, efficiency, and scalability, positioning it as a cornerstone for the future of electric mobility.

The standard induction motor and its shortcomings

Induction Motors (or asynchronous motors) are well known work horses in industrial applications and even in automotive drivetrains. They work well and do not rely on magnets. In principle an induction motor replaces the magnets inside the rotor with conductive bars. In operation the stator field rotates faster than the rotor, which induces currents in the rotor conductors. These currents then create the rotor field which interacts with the stator to produce torque. Sounds easy enough, so why are we not using them everywhere?

The issue is low power density coupled with high manufacturing expenses for high efficiency induction motors. Torque density in induction motors is much lower compared to permanent magnet designs and if you want to build them cheaply you will sacrifice efficiency. The difficult bit is the manufacturing of the rotor conductor. For a standard radial flux machine, it must be cast or assembled in a complicated welding or brazing process. The cheapest way is cast aluminum, which has lower conductivity compared to copper and results in higher losses and lower efficiency. Achieving high efficiency in a conventional induction motor requires copper rotor conductors. These can be cast with expensive molds, or they can be assembled using a costly brazing process. When going through this complicated process you will still end up with a machine that will be much heavier or less powerful than a permanent magnet motor, making it undesirable.

Emil’s mission was clear. Make induction motors more powerful with low weight and low manufacturing cost. Achieving Performance without magnets.

Unveiling the SAM Architecture

SAM’s brilliance lies in its axial flux design, a departure from the conventional radial flux motors dominating the market. Unlike radial designs, where magnetic flux flows perpendicular to the rotor shaft, the Emil’s disc-shaped configuration directs flux parallel to the shaft. This allows for a larger rotor radius within a compact footprint, boosting torque density and power output without increasing the motor’s size. The result is a lightweight, high-performance motor that punches above its weight class.

The stator is a core component towards achieving extraordinary performance. Segmented into precise sections, it achieves a slot fill factor exceeding 65 % which describes how much of the available space is filled with copper wire, maximizing space efficiency for enhanced performance.

Our fully automated winding process is exceptionally well suited for mass production – a critical advantage for scaling EV manufacturing. Conventional round wire windings achieve slot fill factors around 40 %. State of the art hairpin designs may reach 60 % but require very difficult laser welding processes or huge machines for a continuous wave winding.

Compared to this we can easily wind a coil segment by segment and use reliable well known welding processes. A similar approach was pioneered in the world of smaller electric motors in hybrid vehicles, where it has already proven itself to be cost efficient.

Meanwhile, SAM’s integrated oil cooling system sets it apart. Oil flows through channels in direct contact with the copper windings, minimizing thermal resistance and maintaining optimal performance even under high loads.

Cooling the rotor conductors is equally important in an induction motor. SAM achieves this feat by integrating cooling channels near the rotor conductors, keeping continuous power up and losses down.

Both of these revolutionary technologies, winding and integrated oil cooling are made possible using advanced plastics. Injection molding is much more manageable on small stator segments and creates advanced geometric features without increasing cost at all.

Together with our manufacturing partner Schlaeger we have developed an advanced injection molded segment design including very thin walls for slot insulation. No need for slot liners. Oil cooling channels, structural support and winding ixation all taken care of with a simple and cheap injection molding process. The best part is no part, the best process is no process.

The rotor construction is equally impressive, diverging from conventional manufacturing technology. Emil’s axial flux topology allows for major changes and innovation inside the rotor. For example, we can incorporate significant structural reinforcements on the outside of the rotor for high rotor speeds, which is much harder to achieve in a standard radial flux machine.

Manufacturing and assembly of the rotor conductor is simplified, no casting or welding is necessary. This enables the usage of higher performance alloys and a simplified manufacturing process.

As previously explained a conventional induction motor requires copper conductors in the rotor to achieve great efficiency numbers. This is not the case for SAM. The axial flux topology enables big rotor slots with a high cross section. This decreases losses, even when using a material with lower conductivity like aluminum. Additionally, the usage of different alloys makes it possible to achieve higher conductivity compared to cast alloys.

The SAM-M240 showcases these innovations:

• Peak Shaft Power: 330 kW
• Peak Torque: 450 Nm
• Max Speed: 16,000 RPM
• Efficiency: >97 %
• Active Weight: 35 kg (electromagnetic components only)

At just 35 kg of active weight, the SAM-M240 achieves a power-to-weight ratio that rivals permanent magnet motors, proving that magnet-free designs can lead the pack.

These performance claims have been validated through hours of testing data on a test bench. Talk to us directly to get more information on testing and validation of this groundbreaking technology.

A Competitive Edge Over EESM

To appreciate Emil’s significance, consider its magnet-free competitors, such as the Externally Excited Synchronous Machines (EESM) from BMW, ZF and Mahle. EESM technology replaces rare-earth Magnets with an electrically energized rotor, using current to generate the magnetic field. While effective, this approach requires additional power electronics to manage rotor excitation, increasing complexity, weight, and cost. These extra components can also introduce reliability concerns over time, a drawback in high-stakes EV applications.

In contrast, SAM relies on induction motor principles, eliminating the need for rotor excitation systems. By inducing a magnetic field through the stator’s interaction with aluminum conductors in a dual rotor setup, Emil achieves simplicity without sacrificing performance. Its axial flux design delivers torque density on par with permanent magnet motors, while its lightweight construction − just 35 kg of active mass − outshines EESM’s bulkier profile. The motor’s ability to hit 16,000 RPM enables high power capability and low motor weight.

In addition to the increased power density, Emil brings down cost by using an aluminum conductor in the rotor compared to expensive copper windings in EESM technology.

Efficiency is another win. With over 97% efficiency, SAM minimizes energy losses, extending vehicle range − a priority for manufacturers and consumers alike. Compared to EESM, SAM offers a streamlined design, higher power density, and lower production costs, making it a standout choice among magnetfree solutions. It strikes an unrivaled balance of performance, efficiency, and affordability, ready to meet the demands of mass-market EV production.

Strategic Resilience and Sustainability

Emil’s advantages extend beyond the technical. By using widely available materials like copper and aluminum, it eliminates dependence on rare-earth magnets, shielding manufacturers from supply chain volatility. To this day 90% of rare earth magnet production is controlled by China and magnet motors rely on that 100%.

Getting rid of these critical materials in your motor design is the fastest and easiest way to protect against these risks.

We have seen how quickly tariffs can get out of hand and the rare earth supply chain will take a very long time to build up in other countries than China.

For EV manufacturers, this translates to a competitive edge. Emil enables the production of high-efficiency, cost-effective vehicles without the risks tied to magnet-based motors. Its readiness for automated, large-scale manufacturing will accelerate adoption, empowering the industry to meet rising demand without compromise.

Driving the Future Forward

Emil Motors’ SAM technology is more than an engineering breakthrough − it’s a vision for a resilient, sustainable EV ecosystem. With its lightweight design, exceptional efficiency, and magnet-free architecture, SAM redefines what’s possible in electric propulsion. It challenges the status quo, proving that innovation can overcome the limitations of traditional motor technologies.

We invite industry leaders, engineers, and visionaries to experience this revolution firsthand. Visit Emil Motors to explore how we can power your next EV project, enhance your competitive edge, and contribute to a cleaner, more sustainable future. Together, let’s drive electric mobility into a bold new era.