The Quest For A Better Battery Has A Home In Fort Collins
Designing a rechargeable battery is a tradeoff: you can either have more power or faster charging speed. Amy Prieto, a researcher at Colorado State University, wants to make a battery where she doesn’t have to compromise.
Instead of choosing to focus on a battery with a longer life, more energy storage, or a shorter charging time, Prieto decided to tackle all three. And she’s not doing it in Silicon Valley or some other far-flung tech hub. She’s instead based her company in place that has an innate attraction to her research: Fort Collins, Colorado.
“It was just incredible to find this wealth of people who were interested in renewable energy,” says Prieto.
From the small-scale, like your favorite i-gadget, to the large scale, like an electric car or even power backup for a building, “every device you use is limited by the battery,” says Prieto.
To tackle this challenge, Prieto began with a complete redesign of conventional batteries, which she calls “two dimensional batteries.” Their insides look like a layered stack of pancakes, and their power comes from the two dimensional surfaces where one pancake touches another.
“In a conventional battery,” says Prieto, “if you want to make it store a lot of energy, you make these layers really thick and that makes the battery slow.”
To paraphrase: the thicker the pancakes, the more energy you can store. The thinner the pancakes, the faster the battery will charge.
With this kind of battery, the only way to add power is to add pancakes. Yet at a certain point, a battery with too many pancakes won’t fit into your cell phone. So she threw the pancakes away and started over, with copper foam that looks a little like a sponge.
Instead of adding layers on top of the sponge, she coats the sponge itself. When it’s finished, the copper skeleton inside the battery is one continuous piece of material. The layers, normally stacked, look more like a jacket covering the copper skeleton. There’s a much larger surface where the layers meet, giving the battery more power.
“This leads to these batteries that are really thin, really light,” explains Prieto.
She can use different types of copper foam, like one that looks like a piece of foil. It has tiny pores, just like the thicker copper foam, and it makes a battery that looks like a drained juice pouch. You can even bend it with your fingers. This flexibility is something Prieto purposely incorporated into her design, which could lead to future batteries of unusual shapes.
She remembers looking at Apple’s new iWatch and thinking, “why not just make it the wristband, so that you could put more useful electronics and utility into the main part of the battery.”
“Amy understood immediately that making a very expensive tech or very cool tech was great but if it wasn’t readily adoptable it wouldn’t get used,” says Headley.
Yet that battery doesn’t exist right now and this makes Prieto Battery a tough sell for investors. Most of Prieto’s work is still in research and development; she can’t say when the finished product will fuel your phone.
That intangibility means she had to really work on how she pitched her business. She also credits Fort Collins, which she says hosts more patient investors – people who are willing to wait while she rethinks and completely rebuilds the rechargeable battery.
“If I had been still in Boston or the bay area I don’t think the investor community in those two places would have had the appetite for something like this,” Prieto says.
The university has been an asset as well; providing access to amenities like inexpensive rent, state-of-the-art labs, scientific journal access and hazardous waste disposal. Colorado State’s Headley agrees that while it might not be Silicon Valley, people in Fort Collins have invention on the brain.
“The more people you talk to the more you’ll get the feeling that people are really excited about innovation and entrepreneurship,” he says.