Using zinc means Imprint’s batteries can have far less “packaging” because zinc isn’t highly reactive with the environment. In other words, the batteries can be made much more thinly. They can also be made as tiny as a few hundred microns thick (the width of a couple human hairs). Batteries that small could power tiny digital smart labels, like freshness detector stickers on food. Zinc also makes Imprint’s batteries more safe and less toxic than lithium-based batteries. The team at Imprint can work on the zinc batteries in the open air. And the zinc batteries are a safer option for creating devices that sit on — or even in — the body. Imagine a lithium battery powering a heart device inside a person’s chest cavity, and the battery leaks lithium into the person’s body.

Even better -- they can be made using 3-d printers!

The other innovation that Imprint Energy has developed is that it’s printing out its batteries using standard screen printing technology. Most batteries are made by coating the materials onto foils, which are then assembled into cells.

In Imprint Energy’s Alameda lab, CEO MacKenzie shows me one of two battery printing machines on site and a variety of screens that look sort of like t-shirt silk screening screens. The battery materials are printed like ink onto the screens in whatever shapes the client requires. Customers will pay a premium for batteries created to the custom shapes of their devices.