Researchers develop diamond battery made from nuclear waste that last thousands of years
A team of scientists at Bristol University have developed a technology that uses radioactive waste to create a nuclear powered battery encased in man-made diamond with a potential lifespan of thousands of years.
The scientists behind the discovery say that it tackles the problems of nuclear decommissioning, clean electricity generation and battery life. The batteries could last 5,000 years, powering equipment such as pacemakers and spacecraft components that need to last for long periods with absolute reliability.
Tom Scott, a physics professor at the University of Bristol, said: “There are no moving parts, 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.”
Britain has almost 95,000 tonnes of spent graphite blocks, used to house uranium rods in nuclear reactors. Extracting carbon-14 from the blocks’ surface decreases their radioactivity, reducing the long-term cost of safely storing the waste by billions of pounds.
When the blocks are heated, much of the radioactive carbon is given off as gas. This can be collected and converted into radioactive diamonds using a high-temperature chemical reaction, in which carbon atoms are deposited on to a surface in small, dark- coloured diamond crystals.
These crystals give off a small electric current. To be used safely, a non-radioactive diamond layer is formed around them. The surface of a resulting diamond battery unit emits less radiation than a banana. The team has created working diamond batteries from nickel-63. Another radioactive isoptope that is more stable than carbon-14. They will create their first carbon-14 batteries in the coming months.
A diamond battery containing 20g of carbon-14 would deliver 300 joules of energy per day, much less than the 14,000-joule output of an ordinary AA battery. The AA battery, however, would run out in 24 hours, while the diamond battery would take 5,730 years to fall to 50% power and the end of its useful life.
This story was written by Liz Gyekye, editor of Bioenergy Insight magazine.