Lightweight garage #36 Fiber-reinforced plastics @ BMW i3

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Lightweight garage, News

The vehicle

The first BMW i3 rolled off the production line in 2013. As the first electric vehicle, the model was a revolutionary step for the Bavarian car manufacturer. Equipped with permanently excited synchronous motors with an output of 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 seconds.

© Ownership: 2014 BMW i3 Premiere, CC BY-NC-ND 2.0

Production of the i3 was discontinued in 2022. In total, over 200,000 units rolled off the production line. We are taking this opportunity 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 for the body of the i3. The chassis was made from aluminum, with green electricity being used in the production of the material.

The passenger cell was made from 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 construction 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 being recycled or made from renewable materials.

© MotorBlog: IAA 2013: BMW i3, Image:, CC BY 2.0

Great emphasis was also placed on the sustainability of the interior solutions. The door panels and instrument panel were made from bio-based composite materials. Natural fibers from Kenaf were used. The seat covers were made from a PET recyclate.

The lightweight aspect

Thanks to the extensive lightweight construction measures, the total mass of the vehicle is 1345 kg and is comparable with similar vehicles equipped with a combustion engine.