Team used fission products to generate small amounts of power
Researchers at a US university have developed a battery capable of converting fission products from spent nuclear fuel into electricity through light emission, according to a study.
Using a combination of scintillator crystals, high-density materials that emit light when they absorb radiation, and solar cells, the team, led by researchers from The Ohio State University, demonstrated that ambient gamma radiation could be harvested to produce a strong enough electric output to power microelectronics, like microchips.
To test the battery, which is a prototype about four cubic centimetres small, researchers used two different radioactive sources, caesium-137 (Cs-137), and cobalt-60 (Co-60), some of the most significant fission products that come from spent nuclear fuel. The battery was tested at Ohio State’s Nuclear Reactor Laboratory.
Their results showed that when Cs-137 was used, the battery generated 288 nanowatts. Yet with the much stronger radioisotope Co-60, the battery produced 1.5 microwatts of power, about enough to switch on a tiny sensor.
Raymond Cao, lead author of the study and a professor in mechanical and aerospace engineering at Ohio State, said such devices could be scaled up to target applications “at or beyond the watts level”.
The researchers said these batteries, which are not designed for public use, would be used near where the spent nuclear fuel is produced, such as in nuclear waste storage pools or nuclear systems for space and deep-sea exploration.
Although the gamma radiation used in this work is about a hundred times more penetrating than a normal X-ray or CT scan, the battery itself does not incorporate radioactive materials, meaning it is still safe to touch.
Scaling up technology up could be costly unless these batteries could be reliably manufactured, said Cao. He said further research is needed to assess the batteries’ usefulness and limitations, including how long they might last.
