One of the main problems up to now has been that these systems need power to function, and the battery for such a device can be much larger and heavier than the device itself. The ambition for the research team has been to develop an energy source that is both small and light, and produces more power for a longer time.
Another barrier to overcome was that the use of a radioactive battery normally means, when you harvest the energy, that part of the radiation energy can damage the lattice structure of the solid semiconductor; however, by operating with a liquid semiconductor, that problem can be minimized.
The team, from the University of Missouri, whose research has previously been published in the Journal of Applied Physics Letters [doi:10.1063/1.3160542] and Journal of Radioanalytical and Nuclear Chemistry [doi: 10.1007/s10967-009-0157-9], have therefore developed a nuclear energy source that is smaller, lighter and more efficient than previously created, based at the university's research reactor.
Microscale devices, smaller than a computer chip, are already used to deploy airbags, sense tire pressure, work in jet printers, measure biological contaminants, and perform scientific tests. But there is a great need for systems that contain more power and last longer, which is why the radioisotope battery has been created, as a means of producing power with a high energy density. The device that the team is working on can provide power density six orders of magnitude higher than chemical batteries.
The researchers are quick to allay concerns over safety, arguing that nuclear power sources are already powering a variety of devices, such as pace-makers, space satellites and underwater systems. In addition, and mentioning that due to the advanced sealing and packaging technologies with lower shielding required materials, the nuclear power source will safely power without any of the problems that the public associates with nuclear energy.
As Dr. Jae Kwon points out, the research “has shown a new path for the nuclear battery research”, and it is expected thats further promising results will follow. The team will now move on to developing and improving its efficiency and higher output power, as well as decreasing its size (perhaps, one day, to the width of a human hair), as well as testing various other materials. Although there is a long way to go before the battery is ready for commercial marketing, such an efficient and long-lived power source would be a popular one in the industry.