Plug-in Mercedes A250e and B250e make debut

Plug-in versions of the Mercedes-Benz's latest A-Class and more practical B-Class have been revealed ahead of their launch in Europe later this year.

Unconfirmed for the Australian market, the Mercedes B250e people-mover and the A 250e (available in both hatch and sedan forms) marks the first time the German car-maker has offered a hybrid version of its smallest models.

Combining the regular car's small turbocharged 1.33-litre four-cylinder engine with a punchy 75kW/300Nm electric motor and a modestly-sized 15.6kWh lithium-ion battery, together the plug-in powertrain produces a total of 160kW and 450Nm of torque.

Incorporating the electric motor within its already-compact eight-speed dual-clutch automatic transmission, all that torque and power is fed to the front wheels.

This, perhaps surprisingly considering its fuel-saving credentials, means the small A250e can launch itself from standstill to 100km/h in just 6.6 seconds before topping out at 235km/h.

Most will buy the plug-in A250e or B250e because of its ability to cover an NEDC-verified pure-electric range of between 70-75km.

Combined, Mercedes claims the most efficient versions of the A250e can average 1.4L/100km while emitting just 32g/km of CO2.

Topping up from a low 10 per cent charge to 100 per cent is said to take 1 hr 45 min using a 7.4kWh wall box.

A rapid charger, meanwhile, can fill the batteries from 10-80 per cent in just 25 minutes.

Claimed to feature 'ingenious' packaging for a small plug-in, the water-cooled battery pack is claimed to weigh 150kg and is neatly packaged beneath the rear seats resulting in minimal impact on boot space.

Even the exhaust has been re-routed to end in a central position under the floor to make room for the batteries.

Claimed to harness the power of its third-gen plug-in technology, the little Mercedes is said to be cleverer than ever, knowing when and where to deploy its electric power for the most efficient drive, factoring in navigation data, speed limits and traffic conditions.

The MBUX infotainment system has also been optimised and is capable of finding the nearest available charging stations on the move.

In Europe, prices for the A250e hatch start at €36,944 ($A60,500) with some Euro markets charging around $5000 more than the petrol-powered A 250 that offers similar performance to its plug-in cousin.