The size and shape of your favorite gadgets are often determined by one limiting factor: the battery. But that may soon change thanks to a breakthrough from scientists at Linköping University in Sweden, who have developed a new kind of battery with a unique “toothpaste-like consistency”—a flexible, stretchable power source that could redefine how electronics are designed.

Instead of the traditional solid electrodes found in today’s batteries, this innovative design uses liquid electrodes, allowing the battery to bend, twist, and stretch without losing its ability to supply power. In a successful early test, the team used the battery to power an LED both in its relaxed form and while it was being deformed.

This kind of flexibility could lead to major changes in the form factor of future devices. With batteries no longer confined to rigid shapes, designers may be able to integrate power sources into unconventional areas—like the strap of a smartwatch, the hinge of a folding phone, or even wearable textiles. Because the material can also be 3D printed, it opens the door to creative, custom energy solutions tailored to unique product designs.

One of the most promising applications is in wearable tech, where space is limited and flexibility is key. For example, smartwatch manufacturers might soon be able to embed batteries into the watch band itself, significantly boosting battery life without increasing bulk. Similarly, foldable phones and bendable laptops could benefit from batteries that can adapt to the shape of the device rather than the other way around.

However, don’t expect to see this technology in consumer devices just yet. The current prototype delivers only 0.9 volts—enough to power a small LED, but far from sufficient for a smartphone or laptop. The research team’s next challenge is increasing the battery’s output. “One option that we are exploring is the use of zinc or manganese, two metals that are common in the Earth’s crust,” said Aiman Rahmanudin, assistant professor at Linköping University.

Though still in its early stages, this toothpaste-like battery could one day power a new era of flexible electronics—where the form of your device is finally free from the constraints of traditional battery design.

By Impact Lab