The Vehicle

In 2013, the first BMW i3 rolled off the production line. As the first electric vehicle, the model was a revolutionary step by the Bavarian automaker. Equipped with permanently excited synchronous machines with the power between 125 and 134 kW, the i3 had a range of 190 km, which increased to 310 km with the further development of battery technology. The latest version of the i3 accelerates from 0 to 100 km/h in 7.3 s.

Production of the i3 was discontinued in 2022. In total, more than 200,000 units rolled off the production line. We used this occasion to take a look at the lightweight materials used in the i3 as part of the Lightweight Garage.

The Technology

Numerous lightweight materials were used in the body of the i3. The chassis was made of aluminum, with green electricity used in the material production.

The passenger cell was made of a carbon fiber-reinforced plastic (CFRP), which has very good specific mechanical properties. This makes it possible to achieve a high level of rigidity in the structure while keeping the mass low. The roof of the i3 is also made of CFRP. Thermoplastic elastomers were also used in the i3. Almost the entire outer skin is made of polypropylene/ethylene-propylene-diene rubber, with around a quarter of the thermoplastics recycled or produced from renewable materials.

In the interior, too, great emphasis was placed on the sustainability of the solutions. The door panels and instrument panel were made from bio-based composites. Kenaf natural fibers were used. The seat covers were made from a PET recyclate.

The Lightweighting Effect

Due to the extensive lightweight construction measures, the overall mass of the vehicle is 1345 kg and is comparable with similar vehicles equipped with an internal combustion engine.