At CES 2022, BMW showed a version of its all-electric iX that can wear white one minute and black the next. It is called the iX Flow. Electrical signals pull different pigments to the surface of a body wrap, and the car’s skin changes shade.
Adrian van Hooydonk, head of BMW Group design, called it “an advanced research and design project and a great example of the forward thinking that BMW is known for.” BMW says it is pushing the technology along so that a new kind of personalization could reach the outside and inside of future production vehicles.
What is inside the wrap
The coating is based on E Ink, the electrophoretic technology best known from e-reader screens. It holds many millions of microcapsules, each about as wide as a human hair. Every capsule carries negatively charged white pigment and positively charged black pigment. An electric field drives one or the other to the surface of the capsule, and the body takes on that shade.
Fitting that to a car took work. The wrap is built from many precisely cut e-paper segments. BMW used generative design so the segments follow the car’s contours and the way light and shadow fall across them, and laser cutting to make each piece accurately. Once the segments are on and wired to the power supply, the whole body is warmed and sealed so every color change looks even.
The technology needs no energy to hold a color. Current flows only during the brief change.
Efficiency claims
BMW argues color can do more than express a driver’s mood. A white surface reflects much more sunlight than a black one, so switching to a light shade in strong sun could reduce heating of the vehicle and cabin. A dark skin in cool weather would soak up more warmth from the sun. Either way, BMW says, the air conditioning has less to do, which lowers energy use and, in an electric car, could help range. In the interior, the company suggests, the same approach might keep a dashboard from overheating.
These are BMW’s own projections for a research car, not measured results.
A tweet from Out of Spec Studios on January 4, 2022, said the car is “apparently very temperature sensitive,” and that BMW kept a backup in a trailer in case the one on display got too hot or too cold.
