Betavolt Technology is ready to mass-produce radioisotope power for personal devices.
Beijing-based Betavolt New Energy Technology Company has developed an atomic energy source, miniaturized into a form factor approximately ½ inch square and less than ¼ inch thick. The first production batteries, called BV 100, are expected to have a lifetime of 50 years, delivering 1/10 of a milliwatt of power at 3 Volts.
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Episode Transcript:
For three decades now, the development of personal electronic devices such as laptops, tablets and smart phones has literally tethered consumers to an inescapable need: charging. USB power is more important than Wi-Fi connectivity in many public spaces like airports and hotels, and it’s now essential in transportation as well, from jet airliners to pickup trucks.
Battery technology is limited by electrochemistry, but there is another possibility: nuclear power. Not the fission-generated heat familiar from power plants, but the harnessing of other nuclear processes on a scale small enough to potentially power personal electronic devices.
Beijing-based Betavolt New Energy Technology Company has announced an atomic energy source, miniaturized into a form factor similar to chemical batteries: approximately ½ inch square in less than ¼ inch thick. The first production batteries, called BV 100, are expected to have a lifetime of 50 years, delivering 1/10 of a milliwatt of power at 3 Volts.
That’s a very small amount of power, but state-of-the-art semiconductors are highly efficient, and the battery could provide enough energy to run smart devices, possibly maintaining them in a standby mode even when the main batteries are discharged. And since the output is continuous, the units can push charge into a lithium-ion battery even when the unit is switched off or idle.
Potential industrial uses are numerous, with the very promising possibility of self-powered sensor suites that would be ideal for use in drones and networked industrial equipment.
How does it work? Beta decay is the key to low current, long-life power. Radioactive elements emit beta particles as one form of ionizing radiation. Beta is much less penetrating than gamma radiation, making it ideal for radioisotope batteries because of minimal shielding requirements and simple safety procedures in production and use.
The beta source for the BV 100 is two wafers of Ni-63, 2 µm thick, sandwiched between layers of 10 µm thick single-crystal diamond semiconductor. Current is produced directly in the semiconductor wafers, by creation of electron hole pairs in the diamond lattice as the ionizing radiation passes through.
As a nonthermal process, it’s much simpler than the other solid-state nuclear technology, which uses thermocouples to convert decay heat into current. The phenomenon has been known since the 1970s, but current yields were low with conventional semiconductor materials. Fourth-generation semiconductors using novel forms of carbon, such as carbon nanotubes, promise to increase performance considerably.
Betavolt’s production battery will never power current-hungry devices such as electric vehicles, but as a low current and essentially perpetual energy source, the ability to top off lithium-ion batteries even when a device is idle, or off, could make future personal devices like smart phones operate without charging at all, using the lithium-ion technology as an accumulator.
Disadvantages? Possibly the disposal of end-of-life batteries, since they will likely outlive the devices that they power, but this issue has been dealt with in the past, notably with ionization type household smoke detectors.
The next step? Beta voltage is currently researching other isotopes such as Strontium 90, Promethium 147 and Deuterium, with an eye toward higher power units with service lives of 2 to 30 years.
