Charging and relatively short range are still major issues for electric cars. The automaker Mercedes-Benz is developing a solution that could significantly help with daily commuting. They are working on a special photovoltaic coating (paint) that can be applied to any surface, incorporating a new type of nano-based paint that lets through up to 94 percent of sunlight.
The special paint consists of paste-like solar cells. These are thinner than a human hair, weigh only 50 grams per square meter, and can generate a surprisingly large amount of energy.
The solar coating currently achieves an efficiency of around 20%, comparable to standard photovoltaic panels, but it has several significant advantages over them. Most notably, it can easily cover the entire surface of a car body and is much more flexible. A mere 5-micrometer-thick layer weighing just 50 g/m² is enough.
Meaningful solution Thanks to the application of a special coating, it is possible to achieve a much larger effective surface area. The surface of the painted parts of today's large SUVs measures around 11 m2, which could be practically fully utilized. A medium-sized SUV with a surface area of 10.9 m2 could, according to Mercedes, gain enough energy under ideal conditions annually to cover nearly 12,000 km.
Mercedes states that the average driver in Stuttgart travels 51.5 km daily, and this solution could, on average, cover 62% of this distance. In winter, it would be a fraction, while in summer, it would be more.
The photovoltaic coating should be permanently active and continuously power the traction battery. This would result in ongoing charging of the vehicle, requiring significantly less use of a charger on sunny days than currently.
According to the automaker, the solar coating for electric vehicles is not only characterized by exceptional efficiency. During development, environmental protection aspects were also considered. It contains no rare earth elements, no silicon, and is composed only of non-toxic and easily accessible materials. It can be easily recycled, and production is significantly cheaper than conventional solar modules.
However, it will take a few more years before the first vehicles are realistically equipped with this advanced coating. Mercedes’ development teams are currently working on making the solar coating applicable to all surfaces of electric vehicles, regardless of the angle or shape of the vehicle parts.