One of the quests in solar power is to make solar cells that can be placed ubiquitously, in windows, in paint, in shirts, on smartphones—the list goes on. Now MIT might have produced the thinnest, most flexible solar cell ever. A device thin, flexible and light enough to float on a soap bubble.
“While the solar cell in this demonstration device is not especially efficient, because of its low weight, its power-to-weight ratio is among the highest ever achieved,” MIT said. “That’s important for applications where weight is important, such as on spacecraft or on high-altitude helium balloons used for research. Whereas a typical silicon-based solar module, whose weight is dominated by a glass cover, may produce about 15 watts of power per kilogram of weight, the new cells have already demonstrated an output of 6 watts per gram—about 400 times higher.”
The new solar power device that the MIT researchers produced could even be placed on a helium balloon. Such devices have been one novel suggestion for beaming solar electricity back to the earth for use, for instance. But don’t expect to find the device in your grocery store just yet. MIT cautions that it could take years before such a device reaches any sort of commercial viability.
To produce the new solar cell, the researchers used parylene as both the substrate for the cell and its overcoating. The solar cell itself is made of DBP. The parylene is a commercially available plastic coating. It’s often used to protect implanted biomedical devices and printed circuit boards from environmental damage, MIT said.
“The innovative step is the realization that you can grow the substrate at the same time as you grow the device,” says MIT professor Vladimir Bulović. Bulović, research scientist Annie Wang, and doctoral student Joel Jean published their work in the journal Organic Electronics last week.
The researchers were able to grow the device in a vacuum chamber at room temperature using vapor deposition. As such the process doesn’t require solvent or high temperatures. All of this means that the process to make the solar cells is less expensive.
In developing the test cells, the researchers used glass as the base to build the cell on. “We put our carrier in a vacuum system, then we deposit everything else on top of it, and then peel the whole thing off,” said Wang.
Another interesting thing about the research is that the materials chosen were just examples and perhaps other materials like quantum dots or perovskite crystals, could be grown with the substrate in this manner.
The cell they created was only 80 microns thick. “If you breathe too hard, you might blow it away,” Jean said. So it might be too thin to be viable. But as the researchers refine the process they could develop a more practical means of developing a cell that’s resilient enough to make into a viable solar cell or panel.Tweet