The acronym ELF at Mercedes-Benz does not stand for a fairy-tale creature, but for the “Experimental-Lade-Fahrzeug”, a mobile research project for new charging strategies. The goal: to make electromobility more efficient, interconnected and practical. It is not only about fast charging, but also about topics such as energy backfeeding, wireless charging and robotics. The project brings together research into ultra-fast, bidirectional, inductive and conductive charging – in other words, everything that could happen between the power grid and the vehicle in the future. It is being developed by an interdisciplinary team at Mercedes-Benz in Stuttgart.
Fast charging with MCS and CCS: research at the power frontier
The ELF is equipped with two fast charging systems: the Megawatt Charging System (MCS), originally developed for trucks, and the Combined Charging System (CCS), the standard for passenger cars.
- MCS serves as a testbed for charging powers in the megawatt range. The load limits of batteries, power electronics and cable systems are tested under extreme conditions. The aim is to gain experience for long-haul vehicles and fleets.
- CCS is tested with up to 900 kW charging power – that corresponds to around 100 kWh in ten minutes. Production-ready components are used, whose results should directly feed into future models.
The combination of
both systems is intended to close the gap between today’s serial reality and future high-performance technology. An example of this research is the CONCEPT AMG GT XX, which, according to Mercedes-Benz, can recharge enough energy for around 400 kilometers of WLTP range in five minutes – with an average charging power of 850 kW and peak values over 1,000 kW.
Together with the charging-station manufacturer Alpitronic, Mercedes-Benz developed for this a 1,000-amp CCS charging column. It uses cooling technology from the MCS system and was tested on test benches in Stuttgart. The concept is to be implemented in a new generation of fast chargers in the future – including in the Mercedes-Benz Charging Parks.
Bidirectional charging: The car as an energy storage
In addition to charging speed, the ELF also researches bidirectional charging, i.e., the ability to feed electricity back – into the home, into the grid or to devices. The aim is to integrate electric vehicles into the energy system and thus support grid stability and self-sufficiency.
- AC bidirectional: via an alternating-current wallbox (V2H, V2B, V2G); lower costs, but more complex grid requirements.
- DC bidirectional: via a direct-current wallbox; higher efficiency, but higher infrastructure costs.
First production models – the new all-electric CLA and the GLC with
EQ technology – are already technically prepared for bidirectional DC charging. From 2026, Mercedes-Benz will launch corresponding services in Germany, France and the United Kingdom. The MB.CHARGE Home program is intended to combine vehicle, wallbox, green electricity tariff and access to energy markets.
With a battery capacity of 70 to 100 kWh, an electric vehicle can power a single-family home autonomously for two to four days, according to Mercedes-Benz. Potential savings: up to 500 euros per year, which corresponds to about 10,000 kilometers of free driving. Another research approach is a “virtual energy account,” through which users could flexibly use self-generated solar power – for example at home or on the go at public charging points.
Inductive and conductive charging: Cable, goodbye
For even more comfort, the ELF is also testing wireless and automated charging systems.
- Inductive charging: contactless via in-floor embedded charging plates; currently 11 kW AC charging power. The aim is to test everyday practicality, efficiency and compatibility with different vehicle heights. The technology is particularly interesting for fleets and markets such as Asia and South Africa, where cramped or uncertain charging environments are common.
- Conductive charging: also via charging plates, but with physical contact via underbody connector. Also 11 kW AC, with higher efficiency than
- inductive systems. The vehicle must be positioned precisely over the charging plate. Advantages: no cable wear, barrier-free access, space-saving infrastructure.
Automated charging: When robots guide the cable
Another area of research is robot-assisted charging, especially for high-power fast charging with large cable cross-sections. The technology is meant to automatically connect vehicles to the infrastructure – an advantage for fleets, barrier-free mobility and the premium segment. The work is part of the Charging Unit of Mercedes-Benz Mobility, which is also responsible for building the global Mercedes-Benz Charging Network.
What does that mean?
With the ELF, Mercedes-Benz is aiming to take the next major step in the charging ecosystem – and is practically testing every conceivable variant. The project shows that the group no longer treats charging infrastructure as a mere ancillary task, but as an integral part of its vehicle development. However, it remains open when and at what price these technologies will actually go into mass production. Bidirectional charging in particular depends heavily on regulatory framework conditions, and inductive systems are still expensive and not normatively uniform. The ELF therefore does not provide answers to all charging questions, but many pointers to how complex the future of charging will be – technically, economically and politically. (av) Source: Mercedes-Benz
