The Atomic Battery

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Cost is only one reason why Gadeken says he will not pursue the battery-hungry consumer electronics market. Other issues include the regulatory and marketing obstacles posed by powering mass-market devices with radioactive materials and the large battery size that would be required to generate sufficient power. Still, he says, the technology might some day be used as a trickle-recharging device for lithium-ion batteries.

Instead, his company is targeting market sectors that need long-term battery power and have a comfortable familiarity with nuclear materials.

"We're targeting applications such as medical technology, which are already using radioactivity," says Gadeken.

For instance, many implant patients continue to outlive their batteries and require costly and risky replacement surgery.

Eventually, Gadeken hopes to serve NASA as well, if the company can find a way to extract enough energy from tritium to power a space-faring object. Space agencies are interested in safer and lighter power sources than the plutonium-powered Radioisotope Thermal Generators (RTG) used in robotic missions, such as Voyager, which has an RTG power source that is intended to run until around 2020.

Furthermore, a betavoltaics power source would likely alleviate environmental concerns, such as those voiced at the launch of the Cassini satellite mission to Saturn, when protestors feared that an explosion might lead to fallout over Florida.

For now, though, Gadeken hopes to interest the medical field and a variety of niche markets in sub-sea, sub-surface, and polar sensor applications, with a focus on the oil industry.

And the next step is to adapt the technology for use in very tiny batteries that could power micro-electro-mechanical Systems (MEMS) devices, such as those used in optical switches or the free-floating "smart dust" sensors being developed by the military.

In fact, another betavoltaics device, under development at Cornell University, is also targeting the MEMS power market. The Radioisotope-Powered Piezoelectric Generator, due in prototype form in a few years, will combine a betavoltaics cell with a tritium-powered electromechanical cantilever device first demonstrated in 2002.

Amit Lal, one of the Cornell researchers, offers both praise and cautious skepticism about the DEC Cell. While he's impressed with the power output from the DEC Cell, he said that there are still issues with power leakage. To avoid those potential leakage problems, Cornell is using a slightly larger-scale wafer design. They're also planning to move to a porous design and either solid or liquid tritium to improve efficiency.

Lal also notes that the market for either Cornell's device or the DEC Cell might be squeezed by newer, longer-lasting lithium batteries. Still, there's a niche for very small devices, he believes, especially those that must run longer than ten years.