Frankfurt show: Benz goes range extender

MERCEDES-BENZ has joined the rush to plug into the range-extender car market, revealing a petrol-electric concept version of its all-new B-class at the Frankfurt motor show.

Called the E-Cell Plus – E-Cell standing for the electric drive system and the Plus for the three-cylinder petrol powertrain – the five-seat hatch is said to be a foretaste of the production variant slated for showrooms in 2014.

The new B-class has been designed with a sandwich-floor structure to accommodate a variety of propulsion systems, from conventional petrol, diesel and gas to full electric, hydrogen fuel cell and plug-in hybrid, as the German giant covers all bases for future motoring.

The front-wheel-drive E-Cell Plus has an electric-only range of 100km, extending to 600km after the 1.0-litre petrol engine kicks in. By comparison, General Motors’ pioneering Volt has an electric range of about 60km, extending to 610km on petrol.

Peak power of the E-Cell Plus is 100kW – compared with 111kW for the Volt – with 50kW being contributed by the petrol engine.

Under 60 km/h, the combustion engine runs a generator to produce on-board power for the motor in ‘serial mode’, and above 60km/h the petrol engine switches to ‘parallel mode’, driving the front wheels in tandem with the electric motor.

Any excess power generated by the combustion engine is used to charge the battery and to run the ancillary units.

In combined driving mode, the vehicle emits just 32 grams of CO2 per kilometre, compared with 89g/km for the Toyota Prius.

Acceleration from zero to 100 km/h is quoted at about 11 seconds, while the Volt is said to do the sprint in nine seconds.

Like the Volt, the E-Cell Plus employs a lithium-ion battery than can be charged from a home electricity outlet or fast-charging point, but there was no hint in the media materials of its kilowatt-hour capacity.

The battery and petrol tank are both located under a false floor at the rear of the vehicle – the so-called “Energy Space” – which has been developed by Mercedes-Benz specifically for alternative drives.

The “extremely compact” petrol engine and electric drive are in the engine bay at the front, together with the transmission and the generator.

Mercedes-Benz claims the electric-only mode covers more than 80 per cent of daily driving needs for the average motorist, while also being capable of covering long journeys.

Daimler AG board member Thomas Weber said the B-Class E-Cell Plus concept showed that the company’s new range of compact cars was all set for the future.

“The variant involving a battery-electric vehicle with range extender further broadens the range of alternative drive concepts from Mercedes-Benz,” he said.

“This innovative and highly flexible concept meets our customers’ wish for emission-free driving coupled with a large range.”

The vehicle is expected to be offered alongside full-electric B-class models from 2014.

Like Nissan’s all-electric Leaf, the production version of the E-Cell Plus will be capable of online remote checking and remote configuration via a vehicle home page, using a smartphone or PC.

“In this way, it will be possible to check the current charge status of the lithium-ion battery or to verify the vehicle’s current range on a map,” Mercedes said.

The car will also be set up for smart charging, with the driver able to select a desired departure time so the system can ensure that the battery is fully charged and, if desired, that the vehicle is air conditioned.

The show car is distinguished by a copper-coloured flash down the side, while the seats are cloaked in black Nappa leather.