2025 Mercedes-Benz CLA: Pioneering EV powertrain detailed

Mercedes-Benz has revealed yet more of the state-of-the-art 2025 CLA ahead of its launch next year, this time pulling the drapes off its advanced powertrain that will see it deliver class-leading performance and efficiency.

Picking up where the advanced 2022 Vision EQXX left off, the flagship versions of the 2025 Mercedes-Benz CLA will be able to cover up to 750km on a single charge and be DC fast-charged at up to 320kW, gifting it up to 300km range in just 10 minutes.

Helping unlock that long 750km range is an advanced powertrain averages just 12kWh/100km –?beating the 13.2kWh/100km claim of the most efficient Tesla Model 3.

The secret sauce is the next-generation EDU 2.0 (electric drive unit) e-motor which will drive the rear axle and produce a healthy 200kW. A second (80kW) motor will be available on the front axle to provide all-wheel drive.

A larger and more powerful front motor was avoided on the grounds of efficiency and dynamics – the front motor is there simply to boost the larger rear unit – but both can be decoupled for more efficient coasting at highway speeds.

Claimed to provide a battery-to-wheel efficiency of 93 per cent, the CLA gets a two-speed transmission to ensure the motor is always operating at its optimum range, with engineers admitting it’s surprisingly efficient, even at its 210km/h top speed.

Minimising losses, the inverter is features silicon carbide and is packaged with the transmission controller into a single unit.

When the CLA arrives it will be offered with two batteries: low-end variants will score a 58kWh lithium iron phosphate (LFP) unit good for up to 600km while higher-end versions nab a more advanced 85kWh lithium nickel manganese cobalt battery (NMC) provides for both the maximum 750km range.

The bigger pack is unsurprisingly the one capable of the 320kW fast-charging, thanks to an anode that uses more silicon oxide within its graphite that can deal better with higher charge rates – not that the German brand wants buyers to focus on those anymore.

In future, Benz wants more attention paid to how much range you can add over a 10-minute period.

The new batteries are also 20 per cent lighter and 30 per cent cheaper to produce than the current powerpacks.

To prove its impressive mix of performance, range and fast-charging, Mercedes has already set a new electric car record after a CLA prototype covered an impressive 3717km in just 24 hours at Italy's Nardo proving ground.

Achieving that high number involved driving the CLA at its top speed and only charging for 10 minutes at a time, with engineers having to stop 40 times over the 24-hour period.

Ensuring the batteries deliver maximum efficiency however hot or cold it is, an intelligent thermal management system has been developed, one that uses liquid cooling and an auxiliary heater. Extensive preconditioning of the battery also allows for the cells to be charged at the maximum 320kW rate.

A heavy-duty casing protects the battery in a crash – Benz even devised its own pole impact test to enhance safety.

Responding to the drop-off in EV uptake, the flexible MMA platform that will underpin the CLA also allows Mercedes to offer the small sedan with electrified combustion powertrains.

First to arrive is an all-new 48-volt mild-hybrid centred around an equally all-new 1.5-litre four-cylinder FAME petrol engine.

Combined with a small 1.3kWh battery and a 20kW e-motor that lives within an eight-speed dual-clutch transmission, the new 1.5-litre mild-hybrid is both lightweight and compact and will output 100kW/200Nm, 120kW/250Nm or 140kW/300Nm with the option of front- or all-wheel drive.

Capable of coasting at speed of up to 100km/h, the new advanced hybrid is said to be able to recuperate up to 25kW of energy under braking, while offering seamless stop-start function that is so smooth it’s claimed to be imperceptible.

The new M252 FAME four-cylinder, meanwhile, gets Benz’s latest friction-cutting Nanosilde cylinder wall treatment and a cylinder head with a partially integrated manifold and turbocharger that neatly segments the exhaust gases to maximise the turbo’s efficiency.

The small petrol also has a high compression ratio (12:1) and runs the Miller cycle combustion process for maximum efficiency at lower revs.

Externally the engine features foam and aluminium pads, plus a double bulkhead to ensure it’s as quiet as a larger luxury car.

Mercedes is yet to announced exactly when the all-new CLA will be released, however officials have already confirmed the MMA platform will spin-off a CLA shooting brake wagon body, plus two SUVs – likely to include the GLA and ‘baby G’.

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