The new Mercedes-Benz CLA will be revealed soon, and it’ll come with two battery-electric powertrains, and the option of an all-new petrol engine, which promises diesel levels of efficiency. The CLA is the first model to be based on Mercedes’ new MMA platform, and has been engineered as an EV first. However, recognising the slowdown in EV sales globally, Mercedes will also offer it with a bespoke mild hybrid powertrain engineered to be frugal.
- New CLA mild-hybrid to get 4-cyl petrol engine making between 136-190hp
- 1.3kWh 48V battery can help the CLA coast at speeds up to 100kph
- CLA EV has a potential real world efficiency figure of 8.3kWh/km
New Mercedes CLA mild hybrid engine
The CLA's new 'M252' 1.5-litre four-cylinder has been designed to be as small as possible as the MMA platform is an EV-native architecture and the engine can only take up as much space as the electric version’s front motor. However, the unit is said to be modular in its construction, and can be scaled up for larger applications.
The cylinders are positioned as close together to keep the block compact, the exhaust manifolds are housed within the cylinder head rather than outside, while the gearbox, electric motor and inverter are all integrated into one unit. Combined, the engine is said to be smaller in every dimension and some 17 percent lighter than Mercedes' current four-cylinder unit. A four-pot was chosen over a triple because of the refinement offered by an even number of cylinders. Additional insulation measures, including foams and covers, have been installed to further mitigate unwanted noise and vibration.
The engine will send 136hp or 163hp through the front axle, or 190hp to both ends in the range-topping CLA 4Matic –Mercedes notes this is a “considerable output per litre”. For reference, the 1.5-litre four-pot in the Mini Cooper C produces 156hp. Our sister publication Autocar UK reports that there is the possibility for uptuned sporting derivatives in the future
As Mercedes is still homologating the engine, there aren’t details regarding its fuel efficiency yet. However, powertrain lead engineer Karsten Krebs told Autocar UK, “we feel you're reaching diesel levels of fuel efficiency with the hybrid powertrain”. This is, in part, thanks to the 27hp EV motor that draws power from a 1.3kWh 48V battery, which allows the CLA hybrid to go short distances in EV-only mode at speeds of up to 100kph. The battery is mounted under the front passenger seat, and charging takes place is via recuperation at up to 25kW under deceleration. Using the electric motor to start the engine means Mercedes could do away with the need for a conventional starter motor, so the start-stop function is “almost imperceptible for the driver”.
New Mercedes CLA EV powertrain details
Mercedes says that efficiency has been a great focus in the development of the MMA platform and its electric drivetrains, which have been engineered with heavy influence from the EQXX concept. The concept recently completed a 1,000km journey across the Arabian desert, delivering a whopping 13.5km per kWh.
The CLA EV has now broken the record for the longest distance covered in 24 hours by an electric vehicle, with the prototype driving 3,717km around Italy's Nardo ring. The company claims that the new drivetrain has potential to achieve 8.3kWh/km in real-world usage and returns a battery-to-wheel efficiency figure of 93 percent. Mercedes also says it is the “one-litre car of the efficiency age”.
The MMA architecture is equipped with 800V hardware as standard, for charging at up to 320kW, giving 10-80 percent top-ups in as little as 10 minutes, as the Nardo showed. The CLA – and the EQA and EQB replacements that will be revealed on the near future – will be offered with a choice of 58kWh or 85kW (both usable capacity) batteries. The larger unit will have silicon oxide anodes, which are said to boost gravimetric energy density by 20 percent compared to the cells currently in use.
Mercedes has not given a maximum range figure yet, but if the CLA’s Nardo run is taken into account, the EV should be able to go over 700km on a single charge, which is more than the Tesla Model 3, BMW i5 and even the larger Mercedes EQE.
Those batteries power a newly designed electric motor on the rear axle with up to 272hp, with 4Matic models adding a second motor with 108hp on the front. The front unit only comes in when needed, and is otherwise decoupled from the drivetrain to minimise wastage. The rear motor is part of an all-new electric drive unit that the brand calls EDU 2.0, which contains a 2-speed gearbox for optimum efficiency at low speeds and highway speeds, and can recuperate energy at up to 200kW under deceleration.
While the older-gen CLA was on sale in India some years ago, it was replaced in the German brand's portfolio here with the A-Class Limousine. There is no word on when the new CLA will come to our market.
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