It’s about more than smart phones and smoke detectors.
The Betavolt radioisotope-powered battery doesn’t have great power output — but it is continuous, suggesting that this technology would be a complement to lithium-ion batteries in many applications such as industrial self-powered sensors.
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Episode Transcript:
Have you ever thought about the ubiquitous USB port? Once, it was about moving data to and from your personal devices, but today it’s really about charging.
Charging devices such as laptops, tablets and smartphones is a pain in the neck. The need to constantly plug-in our gadgets has forced the redesign of everything from hotel rooms to airplane seats, and the need to carry around these damned cords is like some kind of umbilical cord that connects us to the 20th century.
You can’t download power from the cloud, but soon there may be something almost as good: nuclear batteries. Or more accurately, radioisotope batteries, which work by trapping the beta particles emitted by a decaying radioactive wafer.
As the beta radiation passes through an advanced semiconductor capture media, it converts that ionization trail into electric current. These things have been around in one form or another since the 1970s, with low efficiencies. But a Chinese company, Betavolt, has announced that they have developed a production-ready, commercial radioisotope current source in a practical form factor, about ½ inch square and just under ¼ inch thick. That will easily fit into most devices, and the initial unit will deliver 3 Volts at an admittedly meagre 1/10 of a milliwatts of power.
But today’s semiconductors don’t need much power, and since the unit generates current 24/7 and 365 days a year, when your devices are off or idle they can still be pumping current into an onboard lithium-ion battery.
Even if this can’t account for all current needs, it could function the way the gasoline engine in a plug-in hybrid acts as a range extender for the auto battery.
That’s good, but what interests me about this technology is the possibility in sensor design. Engineers have miniaturized many sensors into single chips, but the need to power these things has always been a limiting consideration, especially in embedded systems. Sensors that can deliver signals wirelessly and require no external power, in a small form factor, could be useful for everything from industrial automation to self-driving cars.
I’m big on do-it-yourself, and I use a cordless drill almost every weekend. My corded drill is in the toolbox, but it’s been years since I used it. Nobody likes cords. But with this innovation, cutting the cord is going to be a lot more significant than it is convenient.
