MIT researchers develop thinnest, lightest solar cells ever made
Imagine solar cells so thin, flexible, and lightweight that they could be placed on almost any material or surface, including your hat, shirt, or smartphone, or even on a sheet of paper or a helium balloon.
Researchers at MIT have now demonstrated just such a technology: the thinnest, lightest solar cells ever produced. Though it may take years to develop into a commercial product, the laboratory proof-of-concept shows a new approach to making solar cells that could help power the next generation of portable electronic devices.
MIT researchers have produced what they believe is the thinnest, lightest solar cell ever produced, capable of being installed on almost any surface or device. In lab tests, the new process results in a super-thin solar cell that is so light it can be placed on the surface of a soap bubble without causing the bubble to burst. Although the technology is still years away from commercial production, this breakthrough could one day lead to a world without cell phone charging cables, and give us the ability to power nearly any portable device with a built-in solar array without adding substantial weight or bulk.
The unique new process is explained in a paper by MIT professor Vladimir Bulović, research scientist Annie Wang, and doctoral student Joel Jean, in the journal Organic Electronics. An ultra-thin, lightweight solar cell like this one could someday make it possible to add solar power generation capabilities to all sorts of objects, including clothing. Making ever thinner and lighter solar cells has been a goal in the research community, and many developments along the way have illustrated progress. The key to this new process, according to Bulović, is to make the solar cell, the substrate that supports it, and a protective overcoating to shield it from the environment, all in one process.
After spending years testing different materials and techniques, Bulović’s team settled on using flexible parylene film on glass for the first layer of the solar cell. Parylene film is similar to the cling-wrap used in kitchens, but is only one-tenth the thickness. Atop the parylene layer, the solar cell is applied, followed by a final layer of parylene. The parylene film sandwiches the ultra-thin solar cell, protecting it from dirt and damage to enhance the cell’s performance.
“We have a proof-of-concept that works,” Bulović says. The next question is, “How many miracles does it take to make it scalable? We think it’s a lot of hard work ahead, but likely no miracles needed.”