Penny-sized nuclear battery

A nuclear battery with power density that is six orders of magnitude higher than chemical batteries is being developed by researchers in the US.

The team from the University of Missouri is building a small nuclear battery, currently the size and thickness of a penny, intended to power various micro/nanoelectromechanical systems.

Jae Kwon, assistant professor of electrical and computer engineering at University of Missouri, said these applications require a high energy density.

He said: 'The radioisotope battery can provide power density that is six orders of magnitude higher than chemical batteries.'

Although nuclear batteries can pose concerns, Kwon said they are safe.

He added: 'People hear the word “nuclear” and think of something very dangerous. However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.'

A critical part of the nuclear battery is its liquid semiconductor. Kwon said a solid semiconductor is not ideal for a radioactive battery because when energy is harvested part of the radiation energy can damage the lattice structure of the solid semiconductor.

He added: 'By using a liquid semiconductor, we believe we can minimise that problem.'

Kwon is working with University of Missouri chemists to build and test the battery in the university’s labs.

The research team plans to increase the battery’s power, shrink its size and try using various other materials. Kwon and his fellow researchers have applied for a provisional patent.