Electronics are now part of our everyday portables and used in phones, iPads, and laptops. They’re also becoming something we wear, such as those wearable health trackers and watches. However, to some extent, the capabilities of such wearables has been limited by battery. Larger, stronger batteries would be required to do more.
However, bigger batteries also require larger devices that may be uncomfortable for most users to wear. Some of these electronics have also presented safety hazards from time to time.
Researchers are working to solve this problem. For example, a team at Stanford recently found a viable solution to this problem. They developed a “stretchable” and soft battery that uses a specific kind of plastic (or polymer), which is a lot safer than the potentially flammable formulations typically used in regular batteries.
“Until now we haven’t had a power source that could stretch and bend the way our bodies do so that we can design electronics that people can comfortably wear,” shared Zhenan Bao, a chemical engineer. Using polymers or plastics in batteries is nothing new. For a long time, lithium-ion batteries used polymers as electrolytes. Electrolytes are the energy source that carries negative ions up to battery’s positive pole.
Until recently, most of these polymer electrolytes were simply too dangerous for wearable use. They were used in the form of flowable gels that could sometimes burst into flames or leak. To keep such risks at bay, this team of Standford researchers came up with a polymer that’s solid and stretchable. It’s not “gooey” or leaky, but still capable of carrying charge from battery’s one pole to another.
When researchers tested this battery in lab, the battery maintained a constant power output even when it was stretched, folded, or squeezed to half of its total length. The prototype of this battery is a small thumbnail-sized device that stores about half of the energy as compared to a similar-sized regular battery.
One of the team members, David Mackanic, says their team is further working to enhance the energy density of this stretchable battery and create larger versions of this device. They will keep on working to demonstrate the performance even outside the lab.
The quest to develop such a flexible battery is not only limited to Stanford. A team of MIT engineers also recently developed a process that may become the key to stretchable electronics. They finally found a way to get over the rigidity of computer chips located in the core of all electronic devices. The aim is to make flexible, more multi-functional electronic devices.
The MIT team believes the process can be used in the production of stretchable electronic films for various purposes, including solar-powered skin or electronic fabrics.