It uses E Ink for color change, similar to a Kindle ereader.
Although it sounds impossible to change a car’s exterior color by pressing a button, the technology has been in development for for well over a decade. Although it has not yet been mass produced, BMW’s new iX Flow concept is a sign that at least one automaker is working towards this goal. Although it can’t yet switch from red to blue to black, the iX Flow concept, which was unveiled at this year’s CES is a great first step.
E Ink is used to create the color-changing exterior of the iX Flow. This is the same stuff that powers e-readers such as the Amazon Kindle. BMW wrapped the with a custom wrap that contained millions of microcapsules E Ink. This wrap is approximately the same thickness as a human hair. Each capsule contains both negatively charged white and positively charged black pigments. The microcapsules are then subject to an electrical field that causes the black or white pigments to accumulate on their surface.
Although it may not seem like much, changing from gray to white is a simple way to make a difference in the real world. BMW states that depending on the season, changing the color of the car from white or gray can heat or cool its interior. The white exterior will reflect the heat of the summer sun and absorb the warmth. On a cold morning, the darker shade can reduce heating time.
Electrophoretic technology is also energy-efficient, as the current flows only when the color changes. BMW promotes the technology as a way to express oneself further, like a status symbol or fashion. BMW has not yet said if the technology will be available in a production vehicle, but it would be a great feature to charge $15 per month for access.