Printable and flexible battery – A revolution in wearable technology

Printable and flexible battery – A revolution in wearable technology

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 ultrathin 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.

Image credit: Imprint Energy

Imprint Energy was founded in 2010 to reshape the battery landscape through the commercialization of its breakthrough, zinc-based rechargeable battery technology (ZincPoly™) developed by the company's founders at the University of California, Berkeley. It aims to improve portable power by significantly lowering its cost and by removing form factor limitations and safety concerns. Imprint Energy's novel electrochemistry system utilizes non-toxic, non-volatile materials that enable scalable, print-based manufacturing of ultrathin, flexible, rechargeable batteries with high energy density.

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. Brooks Kincaid, the company’s cofounder and president, says the batteries combine the best features of thin-film lithium batteries and printed batteries. Such thin-film batteries tend to be rechargeable, but they contain the reactive element, have limited capacity, and are expensive to manufacture. Printed batteries are non-rechargeable, but they are cheap to make, typically use zinc, and offer higher capacity.

Working with zinc has afforded the company manufacturing advantages. Because of zinc’s environmental stability, the company did not need the protective equipment required to make oxygen-sensitive lithium batteries.Imprint Energy aims to reshape the battery landscape. Currently available battery technologies limit the pace of improvement in design and functionality of portable electronic devices. Imprint Energy will address these shortcomings with its breakthrough zinc-based rechargeable battery technology, ZincPoly™. ZincPoly™ battery technology removes longstanding limitations on the rechargeability of zinc-based batteries and enables the production of ultrathin, flexible, high energy density rechargeable batteries for significantly lower cost and without the design limitations or safety concerns of other battery technologies.

It may not be possible for one battery technology to address every power need effectively, but Imprint Energy appears to be taking aim at several of them. Once its technology begins to catch on, we might say goodbye to the button battery.