This stretchy, bendy battery could power a new generation of flexible phones

ETH Zurich flexible battery
(Image credit: ETH Zurich)

Swiss scientists have developed a stretchy, flexible battery that could power a new breed of phones that can be folded, bent and even rolled.

The prototype flexible thin film battery was created by Professor Markus Niederberger and his team at Switzerland's ETH Zürich technical university. It uses a new type of electrolyte (the material through which lithium ions move when the battery is charged and discharged), discovered by doctoral student Xi Chen.

The electrolyte takes the form of a gel containing water with a high concentration of lithium salt, which is far less flammable and toxic than liquid electrolytes in today's commercial batteries.

This gel is sandwiched between two stretchable current collectors, lined with a thin layer of silver flakes that lie over one another like roof tiles, enabling them to maintain conductivity even when the battery is bent.

Into the fold

Foldable phones are an exciting concept, and earlier this year manufacturers seemed to be falling over themselves to release the first bendable production handsets, but the two major models (the Samsung Galaxy Fold and Huawei Mate X) have been beset with problems and delays.

Phones aren't the only possible application for the bendy battery, though; Niederberger also sees potential uses in flexible tablets, watches, and even fashion. "For instance, you could sew our battery right into the clothing,” he said.

Smart garments are certainly interesting (Google recently rebooted its Project Jacquard concept with a smart Yves Saint Laurent backpack), but Niederberger is keen to point out that the bendy battery needs more development before it'll be ready to stitch into your clothes. For the time being then, fully foldable devices are still on standby.

Via Tom's Guide

Cat Ellis
Homes Editor

Cat is TechRadar's Homes Editor specializing in kitchen appliances and smart home technology. She's been a tech journalist for 15 years and is an SCA-certified barista, so whether you want to invest in some smart lights or pick up a new espresso machine, she's the right person to help.

Latest in Phones
Apple iPhone 16 Review
The latest iPhone 18 leak hints at a major chipset upgrade for all four models
Google Pixel 9 Pro Fold main display opened
Apple is rumored to be prioritizing battery life on the foldable iPhone – which could also feature a liquid metal hinge for added durability
Google Pixel 9
The Google Pixel 10 just showed up in Android code – and may come with a useful speed boost
The home screen on an iPhone 16e smartphone
I think the iPhone 16e is too expensive – and as it turns out, so does nearly everybody else
Apple iPhone 16 on orange background with big savings text overlay
You can get a free iPhone 16 Pro Max without a trade at Verizon right now - with one minor catch
Samsung Galaxy Z Fold 6 in Paris in front of the Louvre pyramid
5 things I want from the Samsung Galaxy Z Fold 7
Latest in News
Ray-Ban Meta Smart Glasses
Samsung's rumored smart specs may be launching before the end of 2025
Apple iPhone 16 Review
The latest iPhone 18 leak hints at a major chipset upgrade for all four models
Quordle on a smartphone held in a hand
Quordle hints and answers for Monday, March 24 (game #1155)
NYT Strands homescreen on a mobile phone screen, on a light blue background
NYT Strands hints and answers for Monday, March 24 (game #386)
NYT Connections homescreen on a phone, on a purple background
NYT Connections hints and answers for Monday, March 24 (game #652)
Quordle on a smartphone held in a hand
Quordle hints and answers for Sunday, March 23 (game #1154)