A new electric smart car unveiled at the IAA motor show in Frankfurt achieves a 20 per cent increase in range simply through the selection of more efficient construction materials.
The Smart Forvision concept is a collaboration with Daimler and BASF that utilises non-drivetrain aspects such as temperature management, organic photovoltaics (PVs) and LEDS, as well as lightweight plastics to increase range.
‘Everyone is completely focused on the battery, but nobody thinks about the other things — that was the goal of this project,’ Dr Olaf Kriha, project manager at BASF, told The Engineer.
The Smart Forvision uses a transparent, infrared-reflective film in the windscreen along with infrared-reflective nano-paint and insulating foams in various panels to achieve an interior temperature reduction of around 4°C. The seats also contain conductive textiles, which only heat the body in the areas that absorb heat most efficiently.
‘In electric cars all the energy you need for climate control — either for heating or cooling down — is directly taking away from the capacity of the battery. Temperature management is actually very easy, it’s based on passive materials, you just need to insulate the car and you use less energy,’ Kriha said.
Weight-saving measures on the Forvision include what Smart claims is the first mass-producible, all-plastic wheel, which uses long-glass-fibre-reinforced polyamides to shed 3kg off the standard aluminium version.
‘It’s a very big step with the wheel rims because it’s very sensitive, everybody sees it, and when it becomes clear it’s plastic and not metal maybe people are afraid,’ Kriha said. ‘When they think about plastic wheel rims they think about spontaneous breakage like glass, but that’s not the case with our material.’
Despite this optimism, Kriha said the wheels will require a further 3–5 years of testing before they could conceivably be featured on a production vehicle.
Perhaps most ambitiously, the Forvision incorporates a ‘sandwich roof’ with a layer of transparent, organic PVs on the outside and OLEDs on the inside. Arranged as hexagonal cells, the PVs provide enough power for the multimedia system and three cooling fans, BASF claims.