Graphene electrodes will help create flexible and invisible solar cells

Why did Tesla start disguising its solar panel models as banal roof tiles a few months ago? Now that the energy of our star can be exploited by anyone with money, arrays of solar panels have gone from a prestigious landscape feature to an eyesore. They strive, if not to hide, then as imperceptibly as possible to embed them into the general landscape.

Organic solar panels are inferior to silicon-based counterparts in a number of parameters, but at the same time they are lighter, cheaper and, most importantly, almost transparent. A great platform to experiment with stealth battery design, but the presence of metal electrodes spoils everything. But what if you replace the metal with graphene? With a conductor thickness of one atom, it is obviously invisible to the human eye, no matter how extensive the electrical network is.

However, it is difficult to work with graphene; standard engineering solutions are only harmful here. Yi Song of the Massachusetts University of Technology says bluntly that they were lucky to stumble upon an interesting option. Instead of gluing graphene to a substrate, which degrades the properties of the conductor, they simply deposited two layers of graphene on the sides of a thin EVA tape. It serves as the basis of the structure and at the same time as insulation.

The energy conversion efficiency of a battery with graphene conductors reaches a factor of 4, 1 - much worse than that of traditional designs, but the best indicator among "transparent" batteries. Of course, this is a convention, even with an imperceptible graphene inside, the panel allows only 70% of the light visible to humans to pass through, but again, this is the highest rate at the moment.

Scientists expect that in the future they will be able to increase the efficiency of panels with graphene electrodes by another 10% without losing transparency. They will look like a smoky flexible curtain, almost weightless but strong enough to be mounted without an additional frame. And, in theory, such panels can be applied to walls and even windows, like transparent varnish, without compromising the aesthetic component of the interior.