Researchers develop new croissant-inspired energy storage system

Researchers have developed a new dielectric capacitor -- a device that stores energy like a battery -- taking inspiration from how the French pastry, croissant, is made by folding multiple layers of dough.

The researchers, including those from Queen Mary institute of London in the UK, found that by pressing and folding a polymer film capacitor (a capacitor with an insulating plastic film), they were able to store 30 times more energy than the best-performing commercially available dielectric capacitor.

According to the study, published in the journal Nature Communications, this is the highest energy density ever reported in a polymer film capacitor -- an advance that may pave the way for efficient, low-cost, and environmentally friendly electric energy storage systems for wind and solar sources.

"Storing energy can be surprisingly tricky and expensive and this is problematic with renewable energy sources which are not constant and rely on nature. With this technique we can store large amounts of renewable energy to be used when the sun is not shining and it is not windy," said Emiliano Bilotti, lead researcher of the study from Queen Mary University of London in the UK.

The study noted that dielectric capacitors generally have ultrahigh power density making them suitable for technologies such as motor drives, and space vehicle power systems which require accumulating energy over a period of time, and then releasing it very quickly.

Until now, the researchers said that such capacitors were limited by the low amounts of energy they could store.

"This finding promises to have a significant impact on the field of pulse power applications and could produce a step change in the field of dielectric capacitors, so far limited by their low energy storage density," Mike Reece, co-author of the study from Queen Mary University of London.

The researchers said that the newly developed technique of processing, pressing and folding layers to make the dielectric capacitors is unique for its simplicity, record high energy density, and the potential to be adopted by industries.