Mercedes-Benz has set a new electric car distance record during testing of its third-generation CLA.

Building on the benchmarks established by the sleek EQXX engineering concept, a prototype of the new saloon covered 2309.6 miles within a 24-hour period at the Nardò test track in Italy

This surpasses the 24-hour distance of 2128.2 miles set by the Porsche Taycan on the same 7.9-mile banked oval in 2019.

Based on the Mercedes-Benz Modular Architecture (MMA) platform, the CLA is the first of four new compact electric models the German car maker plans to launch by the end of 2026. Successor models to the CLA Shooting Brake, EQA and EQB are also in the pipeline.

All four models feature a newly developed 800V electric architecture – the first of its kind to be used by a series-production Mercedes-Benz – in combination with new-generation electric motors, heat pumps and the MB:OS operating system.  

The CLA prototype used for the record attempt was taken from a fleet of production-based engineering mules already undergoing durability testing ahead of the model's planned launch early next year. It ran alongside a back-up prototype. Both cars featured a driver and front passenger as well as data loggers and other test equipment.

Key to the record was a clever charging strategy, dubbed “plug and dash”, which was developed to maximise driving time. Rather than dipping well into the energy reserves on long periods of driving before recharging, Mercedes-Benz opted for shorter driving stints paired with frequent charging stops.

“Regular charging brings a decisive advantage in both distance and time efficiency – essentially, how many kilometres or miles can be driven for every minute of charging,” said Christian Pfeiffer, team lead of Mercedes-Benz’s latest electric drive system.

The CLA prototype underwent a total of 40 recharges during the 24-hour attempt, each around 10 minutes in duration. 

Overall, the prototype was stationary for close to 28%, approximately six hours and 40 minutes, of the 24-hour record attempt. These short but regular stops enabled Mercedes-Benz to take advantage of a boost function that allows a high initial charging rate on a DC system compared with the average achieved over longer but fewer stops.

Mercedes-Benz has yet to reveal the charging capacity of its upcoming electric model, but it has previously hinted it will be capable of accepting charge at around 250kW, with an additional 50kW boost function allowing it to reach 300kW for short periods. This will enable a 249-mile top up in just 15 minutes.

The energy capacity of the new model’s lithium ion battery also remains under wraps, though it is claimed to be 89.6kWh. This is said to provide the new CLA with an average consumption of around 5.2mpkWh and an overall range of up to 466 miles, making it one of the most efficiency and longest-ranged cars on sale.

Production versions of the new model are also expected to offer a less energy-dense lithium-ion-phosphate unit as a cheaper option.

The CLA used in the record attempt was a rear-wheel-drive model featuring a single rear-mounted synchronous electric motor and two-speed transmission. Again, technical details have yet to be disclosed, though Mercedes-Benz is claimed to be developing the new saloon with drivetrains offering between 202bhp and up to 537bhp in an AMG-branded dual-motor, four-wheel-drive performance model.

Despite being developed as an “electric first” model, the new saloon will also be sold with a turbocharged 2.0-litre petrol engine paired with a gearbox-mounted motor.

Developed by Mercedes-Benz, the new four-cylinder petrol engine will be produced in China by Horse Powertrain – a company jointly operated by Chinese car maker Geely and France’s Renault. Leaked specifications reveal the new unit, known internally as the M252, develops 249bhp and up to 266lb ft of torque in an initial state of tune, although this has yet to be confirmed by Mercedes-Benz.

Mercedes-Benz boss Ola Källenius said: “With the CLA, we are ushering in a new era at Mercedes‑Benz. We will substantially elevate every aspect of what our customers can expect from a Mercedes in this segment. 

“The modular platform allows for maximum flexibility. We can offer the CLA in both a state-of-the-art electric drivetrain version and a hybrid electrified combustion-engine version. 

And our operating system, MB.OS, will make it the most intelligent car we’ve ever built.”

The third-generation CLA is planned to be revealed next year, with UK sales set to get under way by the end of 2025. Initial models will be electric only, with the hybrid option set to be made available six months after its launch.