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This Smart Watch Will Charge Itself Using Heat From Your Skin

Matrix Industries comes out of stealth today to say that wearables can—and should—power themselves

2 min read
A self-powering watch from Matrix Industries uses thermoelectrics
Photo: Matrix Industries

I actually like tracking my steps, but I’m not wearing my Fitbit right now because I’ve forgotten to charge it too many times over the past couple of months, blowing my step average and my motivation to quantify my self.

Matrix Industries, based in Menlo Park, Calif., is coming out of stealth mode today to say that it can fix that. Company founders Akram Boukai, CEO, and Douglas Tham, chief technology officer, think that thermoelectric technology is ready to power wearables now, and soon will make sense for implantables and low-power sensors on the Internet of Things. Thermoelectric devices harvest energy using a temperature difference between their two sides to generate a voltage.

Matrix launched what it calls a thermoelectric-powered smart watch—and I call a fitness tracker—on Indiegogo today. The US $100 gadget—which has a step counter, calories-expended counter, a sleep monitor, and yes, a watch that tells time—is a little too clunky for me, and will likely only appeal to the “gotta have the cool gadget” early adopter who can show off the self-powering feature to his friends.

But that’s probably okay. Because, while I’m sure Matrix would love to sell a bunch of these gadgets, that’s really not its main goal. The company really just wants to convince other gadget makers to embrace its thermoelectric technology.

“We see ourselves as a thermal energy harvesting company,” Anne Ruminski, Matrix’s head of engineering told me, not a watch company. “We would like to see the technology be applied to other wearables, medical devices, and smart sensors.”

Boukai and Tham started working together on the technology in 2003, as graduate students at Cal Tech. They officially formed as Silicium Energy in Ann Arbor, Michigan, in 2011, moving their operations to Silicon Valley in 2013. Silicium changed its name to Matrix this year.

Matrix Industries comes out of stealth today, with a staff of seven.The team behind Matrix Industry's energy harvesting smart watch: (left to right) Haifan Liang, Martin Tran, Douglas Tham, Akram Boukai, Anne Ruminski, Arjun Mendiratta, Hien NguyenPhoto: Matrix Industries

Ruminski says the time is right for putting thermoelectrics into wearables. “We were surprised that, when we looked at applications for the technology, that everybody working with it was focused on putting it into cars, which isn’t feasible now. We were surprised nobody had put it into a watch.” Smart watches makes sense, because “the devices going into smart watches today use far less power than even just a couple of years ago.”

She would particularly love to see the technology migrate quickly into hearing aids. “A close relative wears hearing aids,” she says, “and it’s a pain for her to change the tiny batteries so often.”

The technology, Ruminski believes, is especially suited for implantables that sit just under the skin, like pacemakers. “They don’t require much power, and there is enough of a temperature gradient at the surface of the skin so it would work.”

The company has filed patents in thermoelectrics and heat management. Figuring out how to shed heat so the cold side of the system  doesn’t get too warm was a challenge, Ruminski says.

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