Crumpling Graphene 'Paper' May Create Super Stretchy Supercapacitors to Store Energy

There could be a new and unconventional method to store energy. Scientists have found that by crumpling a sheet of graphene "paper," it actually takes on new properties that could be useful for creating extremely stretchable supercapacitors to store energy for flexible electronic devices.

"Many people are exploring graphene paper: It's a good candidate for making supercapacitor,s because of its large surface area per mass," said Xuanhe Zhao, one of the researchers, in a news release.

Supercapacitors can store electrical energy, but they primarily do so electrostatically, rather than chemically. This means that they can deliver their energy faster than batteries can. In this case, the scientists found that by crumpling a sheet of graphene paper into a chaotic mass of folds, they can create a supercapacitor that can be ent, folded or stretched to as much as 800 percent of its original size.

"The graphene is pretty robust, and we can achieve very large deformations over multiple cycles," said Zhao.

The scientists took a sheet of graphene material and put it into a mechanical device that first compressed it in one direction. This created a series of parallel folds. Then, the device compressed it in the other direction, which lead to a chaotic, rumpled surface. When stretched, the material's folds smoothed themselves out.

While this initial demonstrate was used specifically to create a supercapacitor, the same technique could, in theory, be applied to other uses. For example, the crumpled graphene could be used as one electrode in a flexible battery.

The findings reveal a potential new component for energy storage that, in the future, could be used for bendable electronics.  That said, future research is needed before this can be practically applied.

The findings are published in the journal Scientific Reports.