“FIU, the University of Miami, they’re graduating thousands of engineers and scientists, and they get out and there aren’t jobs,” said Cabauy, who has a PhD in applied physics from the University of Michigan. “We looked at this and we said, ‘We have to do something. We love Miami. We have to be here.’ ”

Fueled by private investors — including Alex Aguila, co-founder of Dell subsidiary Alienware Corporation — City Labs currently has five full-time employees.

Cabauy lobbied FIU officials to develop the Office of Entrepreneurial Science, which provided office space for enterprising scientists and engineers looking to launch their own businesses.

Next, he and Serralta went looking for a problem that needed solving.

“Being an engineer, scientist, the community starts to talk,” Cabauy said. “We were actively looking for problems that we could solve. So we didn’t fall in love with, ‘Oh we have the technology here for a battery.’ We fell in love with the problem. And we knew that there was a need for long-lived, low-power that can withstand extreme temperatures.”

With a problem defined, Cabauy did what any good scientist would: research. That’s how Larry Olsen, who has a PhD in physics, came onto the scene.

Trolling Spanish online forums, Cabauy read about Olsen’s work on betavoltaic batteries in the 1970s, when Olsen helped created a betavoltaic power source strong enough to power pacemakers. Doctors from Uruguay marveled online that in many cases, the medical devices outlasted the patients. A typical pacemaker, powered by lithium, usually lasts only about 10 years, Cabauy said. That means the patient has to undergo expensive, invasive surgery to replace the device’s battery.

City Labs — which by this time, had begun moving to a business incubator in Homestead — tracked down Olsen and brought him on as a contractor at first, and later pulled him out of retirement to become the company’s director of research.

“The idea intrigued me,” Olsen said. “When this came up, it really was an exciting possibly.”

Olsen’s battery never became mass-produced because lithium batteries came on scene shortly after his was invented. Olsen also was using a more radioactive element, which meant its encasing needed to be bulkier to make it safe.

Since Olsen’s work in the 1970s, the power needed to run devices has gone down dramatically, he said, making products like the NanoTritium possible. City Labs’ battery produces nanowatts of power, which means it isn’t strong enough to power a cell phone or laptop.

It took Olsen’s expertise, money scrapped together from family, friends and investors, years of research and volumes of regulatory paperwork to develop the NanoTritium.

The battery is only currently available in “engineering” quantities — up to 1,000 a year, Cabauy said. They’re assembled in the company’s small Homestead lab, where the ventilation system rumbles non-stop.

“I think the time is right,” Olsen said. “What we’re doing, I think, is really quite viable.”

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