British university unveils 'diamond' nuclear-powered battery

28 November 2016

The University of Bristol, in England, has developed new technology that uses nuclear waste to generate electricity in a nuclear-powered battery. A team of physicists and chemists from the university has "grown a man-made diamond" that, when placed in a radioactive field, is able to generate a small electrical current. The developers say the innovation could solve some of the problems of nuclear waste, clean electricity generation and battery life.

This new method for radioactive energy was presented at the Cabot Institute's annual lecture - Ideas to Change the World - on 25 November. The Cabot Institute is the university's first flagship cross-disciplinary research institute.

In a statement, the university said that, unlike the majority of electricity-generation technologies, which use energy to move a magnet through a coil of wire to generate a current, the man-made diamond is able to produce a charge simply by being placed in close proximity to a radioactive source.

Tom Scott, professor in materials in the university's Interface Analysis Centre and a member of the Cabot Institute, said: "There are no moving parts involved, no emissions generated and no maintenance required, just direct electricity generation. By encapsulating radioactive material inside diamonds, we turn a long-term problem of nuclear waste into a nuclear-powered battery and a long-term supply of clean energy."

The team have demonstrated a prototype diamond battery using nickel-63 as the radiation source. However, they are now working to significantly improve efficiency by utilising carbon-14, a radioactive version of carbon, which is generated in graphite blocks used to moderate the reaction in nuclear power plants.

Research by academics at Bristol has shown that the radioactive carbon-14 is concentrated at the surface of these blocks, making it possible to process it to remove the majority of the radioactive material. The extracted carbon-14 is then incorporated into a diamond to produce a nuclear-powered battery.

The UK currently holds almost 95,000 tonnes of graphite blocks, the university noted, and by extracting carbon-14 from them, their radioactivity decreases, reducing the cost and challenge of safely storing this nuclear waste.

Neil Fox from the School of Chemistry, said carbon-14 was chosen as a source material because it emits a short-range radiation, which is quickly absorbed by any solid material. "This would make it dangerous to ingest or touch with your naked skin, but safely held within diamond, no short-range radiation can escape. In fact, diamond is the hardest substance known to man, there is literally nothing we could use that could offer more protection," Fox said.

Despite their low-power, relative to current battery technologies, the life-time of these diamond batteries could "revolutionise" the powering of devices over long timescales, according to the statement. Using carbon-14 the battery would take 5730 years to reach 50% power.

Researched and written
by World Nuclear News