A California startup is developing flexible, rechargeable batteries that can be printed cheaply on commonly used industrial screen printers. Imprint Energy, of Alameda, California, has been testing its ultra-thin zinc-polymer batteries in wrist-worn devices and hopes to sell them to manufacturers of wearable electronics, medical devices, smart labels and environmental sensors.
The company’s approach is meant to make the batteries safe for on-body applications, while their small size and flexibility will allow for product designs that would have been impossible with bulkier lithium-based batteries. Even in small formats, the batteries can deliver enough current for low-power wireless communications sensors, distinguishing them from other types of thin batteries.
The batteries that power most laptops and smartphones contain lithium, which is highly reactive and has to be protected in ways that add size and bulk. While zinc is more stable, the water-based electrolytes in conventional zinc batteries cause zinc to form dendrites, branch-like structures that can grow from one electrode to the other, shorting the battery. Ho developed a solid polymer electrolyte that avoids this problem, and also provides greater stability, and greater capacity for recharging.
Imprint has also been in talks about the use of its batteries in clothes and “weird parts of your body like your eye,” Ho says. The company also recently began working on a project funded by the U.S. military to make batteries for sensors that would monitor the health status of soldiers. Other potential applications include powering smart labels with sensors for tracking food and packages.
Why It’s Hot:
As we get into more wearables and more technology, one of the best ways to make them smaller and not take as much space is batteries. It can also help with the issue of electronic waste. Every year, people throw out their phones with these huge lithium batteries that can’t be recycled or reused in anyway. With these new batteries, the amount of waste would go down and phones can have more space for the better processors or larger camera.