What if our smartphones stopped looking like bricks? Swedish researchers may have found the key to batteries as flexible as rubber bands. Spoiler: it involves toothpaste… but not the kind in your bathroom.
Foldable screens are great. Rollable smartphones, too. But a truly flexible device? The Achilles’ heel is the battery. Too rigid, it limits bold designs. A Swedish team has just published a novel solution in Science: liquid electrodes as malleable as modeling clay.
Their secret? Transforming key components into viscous fluids. Imagine a battery that can be stretched, twisted, or 3D printed like plastic. Tests show it can withstand 500 stretches of 500% without losing capacity. Better yet, it uses lignin, a waste product from the paper industry. A combination of ecology and high-tech.
Toothpaste electrodes (or almost)
To understand this feat, remember that a conventional battery has solid electrodes. The problem: rigidity and risk of breakage. The team at Linköping University replaced these materials with liquid conductive polymers and lignin. The result? A texture similar to toothpaste, which can conform to any shape.
” Capacity no longer depends on rigidity,” explains Aiman Rahmanudin, co-author of the study. In practical terms, this battery can be integrated into ultra-thin wearables, rollable screens, or even connected clothing. Another advantage: it can be recharged 500 times, even when stretched to 200% of its length.
But there’s still a problem. The voltage is 0.9 volts, compared to 3.7 V for a smartphone. The team is already working on more efficient chemical components. ” We’re first targeting small devices, like medical sensors,” explains Mohsen Mohammadi, another researcher involved.
Ultimately, this innovation could render traditional batteries obsolete. Goodbye bulky cases, hello organic designs. It remains to be seen if the industry will follow suit. Tech giants dream of watches with screens tattooed on the wrist or rollable smartphones … But for that, they need batteries that can withstand twisting. The same goes for foldable smartphones. The Swedes have led the way. Now it’s up to Samsung, Apple, and others to play.
