Many potential buyers of electric vehicles still feel the so-called range anxiety that accompanies all-electric driving.
In these cases, range extenders can be one solution: A combustion generator that is coupled to an electric motor and thus generates energy for the vehicle battery. ZF is now introducing the new generation of this technology, which will go into volume production in 2026. Designed to meet increasing global demand, this further development is ideally suited to meet dynamic market and customer requirements as well as flexible drive concepts.
It is the scary scenario for many electric drivers: the battery’s state of charge is coming to an end with no charging station in sight. This is especially true in regions where a charging infrastructure is not yet universally available. ZF is currently developing the next generation of range extenders for these situations.
Dr. Otmar Scharrer, Senior Vice President R&D, Electrified Powertrain Technology, said:Although the all-electric range of passenger cars is around 500 km on average, range anxiety still influences a wide range of buyers when choosing their next vehicle. These represent a real alternative to larger – and thus more expensive – batteries or plug-in hybrids.
With range extenders, a combustion engine is coupled to an electric machine that generates power for the vehicle battery as soon as its state of charge drops below a certain threshold. As you can already see from the name, this increases the range that can be driven electrically. The advantage compared to PHEVs or conventional combustion engines: The range extender machine always runs in the ideal performance range for fuel consumption, which ensures low fuel consumption and therefore also has lower CO2 emissions.
Zf’s Range Extender Technology: A Lot of Experience, New Developments
In recent years, ZF had already launched range extender technology in volume production. Among other things, ZF’s electric machines were installed in a series of iconic London taxis. ZF is currently working on the next generation, the electric Range Extender (eRE) and the electric Range Extender plus (eRE+).
Both variants are highly integrated designs that are flexible in terms of performance, E/E architecture, 400V or 800V and semiconductor type. The eRE connects an electric motor with an integrated inverter, suitable software and planetary gearset. The eRE+ also has an intelligent clutch and a differential. As a result, it can be used either as a current generator or as an additional secondary drive, which saves manufacturers developing a separate component. Performance can be scaled in both models. The output ranges from 70 to 110 kW (eRE) or 70 to 150 kW (eRE+).
Scharrer said:The new interest and the increased demand for range extenders shows that the potential of this technology is far from exhausted – in particular for model platforms that are already designed for battery-electric drivelines. Behind our solutions is the system and platform concept. This means that we are optimally equipped to be able to respond to all customer and market requirements with shorter development cycles.
What Advantages Range Extenders Offer for Manufacturers and Customers
Compared to parallel-hybrid drive solutions, for example with a PHEV, range extenders are compelling due to their lower additional costs, shorter development cycles, lower platform effort, and simplified supply chain management. This makes the technology particularly interesting for manufacturers who are new to the market, and may have little experience with traditional combustion engine drivelines. China is currently embarking on a proper model offensive of so-called “Range Extended Electric Vehicles” (REEV), which, thanks to the technology, can cover distances of more than 700 kilometers.
Scharrer said:This is where we find it convenient that there is a wide range of BEV platforms that can be supplemented by range extenders.
This was another reason why the Chinese ZF locations were in charge of development.
But also in the USA and in Europe, the interest of manufacturers is increasing.
Scharrer said:The market for all-electric vehicles has not developed as predicted a few years ago. For this intermediate phase, range extenders can be the ideal solution.
Because: With REEV, drivers can enjoy the advantages of electromobility without having to sacrifice the flexibility of PHEVs or combustion engine passenger cars. Range extenders are also worthwhile for traditional manufacturers. They allow smaller (and therefore more economical) vehicle batteries to be installed and help to comply with emission limit values for fleets.
This article was originally published by ZF.
