BMW has unveiled a new varient of its i3 vehicle at the 2012 LA Auto Show, a three door Coupe Concept. Like other vehicles in the ‘i’ range, the vehicle makes extensive use of carbon fiber composite materials to keep it as lightweight as possible in an effort to maximize its range.
BMW is making headlines with the ‘i’ range due to the extensive use of carbon fiber-reinforced plastic (CFRP), a material not commonly used in high production vehicles due to the additional costs and potentially longer manufacturing time.
To minimize weight and boost efficiency, the passenger cell of all ‘i’ vehicles is made of CFRP, while the Drive module (which includes the powertrain and chassis) is almost entirely aluminum. The combination of lightweight, high strength materials has allowed BMW to remove the B-pillar, giving the vehicle a ‘floating roof’.
Like the BMW i3 Concept, the Coupe is also propelled by an electric motor developed by the BMW Group, which develops a maximum output of 125 kW/170 hp and peak torque of 250 Newton metres (184 lb-ft), and channels its power delivery to the rear wheels via a single-speed transmission. The electric motor draws its energy from the lithium-ion storage cells under the floor. Positioning the battery units here has the effect of lowering the centre of gravity considerably. The vehicle is said to have a range of 100 miles per charge.
Earlier this year, we spoke to Dr Joerg Pohlman of SGL Automotive Carbon Fibers about the use of CFRP in the i vehicles. Take a look at what he had to say below.