This betavoltaic battery prototype is based on carbon-14, an unstable and radioactive form of carbon called radiocarbon. Although this carbon isotope is radioactive, it only produces beta radiation, which can be easily shielded to prevent harm.
Radiocarbon is already a byproduct of nuclear power plants and is therefore cheap, readily available, and easy to recycle, according to the researchers. And since radiocarbon degrades very slowly, a battery powered by radiocarbon could theoretically provide energy for decades, centuries, or even thousands of years.
According to the researchers, the latest prototype of this radiocarbon battery has a significantly higher energy conversion efficiency, which has increased from 0.48 to 2.86 percent.
This kind of nuclear battery would only be the size of a finger, and such long-lasting nuclear batteries could enable numerous applications, says Professor Su-Il In. For example, a pacemaker powered by such a battery would last a lifetime and make surgical replacement unnecessary.