Foldable phones deserve foldable batteries, say scientists working on the tech

These stretchy prototype batteries could also be used in rollable displays and even smart clothing.

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Shelby Brown (she/her/hers) is an editor for CNET's services team. She covers tips and tricks for apps, operating systems and devices, as well as mobile gaming and Apple Arcade news. Shelby also oversees Tech Tips coverage. Before joining CNET, she covered app news for Download.com and served as a freelancer for Louisville.com.
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Professor Markus Niederberger's device looks more like taffy than a battery. 

Niederberger Group, ETH Zurich

To keep up with the future of foldable phones, battery makers have to be more flexible. Literally. Enter Professor Markus Niederberger and his research team at ETH Zurich, who have developed a prototype for a "flexible thin film battery" that can be stretched, bent and twisted without halting the power supply.

The battery is built like a sandwich, following the design of commercial batteries, according to an article on the university's website. Between two stretchable current collectors is a cathode, a hydrogel electrolyte, a PDMS frame and sealing and an anode. 

"To date, no one has employed exclusively flexible components as systematically as we have in creating a lithium-ion battery," Niederberger told ETH News.

Niederberger said the possibilities for the foldable battery go beyond phones. The batteries could be useful to rollable displays for computers, smartwatches and tablets, or functional textiles that contain bendable electronics. The battery could even be sewn into clothing, he added.

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