Imagine having a rechargable fluid battery in any shape you want. Why, that would put to bed the old-fashioned idea that batteries come in particular shapes, like AA and AAA. Scientists at Linköping University in Sweden have developed a soft battery, that does not insist on being prismatic, pouch, or cylindrical. Why, this sounds amazing!
A Fluid Battery With a Shape Like Toothpaste
“The texture is a bit like toothpaste”, an assistant professor explains. “This means we can use a 3D printer to shape the battery any way that suits us.” We have not previously encountered this idea, but it suddenly makes sense.
The world is moving in the direction of soft robotics, e-textiles and connected nerve implants, the spokesperson continues. In the meantime, we also have have to accommodate all kinds of wearable medical devices.
A soft battery that conforms to our requirements would remove many of the design limitations, that available fixed battery shapes impose. Flexible batteries should adapt to our designs, surely, instead of the other way around?
Developing a Conformable Battery From Scratch
The scientists at Linköping University began by converting battery electrodes from solid to liquid form. This was quite a departure from soft, stretchable batteries, that rely on a variety of mechanical functions.
This lateral thinking brought the team closer to being able to make a fluid battery in any shape. However, they still faced the problem that increasing capacity required thicker electrodes, and this made their battery more rigid.
There have been attempts in the past to develop fluid electrodes, but these failed for a variety of reasons. The team at Linköping University succeeded, after they combined conductive plastics and lignin from trees.
Their prototype battery, which can stretch to twice its length, achieved 500 recharge cycles while maintaining its performance. Conductive plastics and lignin are both abundant materials, suggesting their battery could become a sustainable alternative.
More Information
Flexible Batteries in Personal Devices
Lignin Battery Recharging Over 8,000 Times
Preview Image: Soft Toothpaste-Like Battery
