BY HARVESTING ENERGY FROM RADIOACTIVE SPECKS,
NUCLEAR MICROBATTERIES COULD POWER
TOMORROWâ„¢S MICROELECTROMECHANICAL
MARVELS-starting from your cellphone.
There has been tremendous research going on harvesting the incredible amount of energy released naturally by tiny bits of radioactive material. All energy comes from high-energy particles
spontaneously emitted by radioactive elements. A speck of a radioisotope like nickel-63 can produce enough power to power a MEMS device for decades along with the proper packaging and safety considera-
tions many useful devices can be built.By using the technique of trickle charging these batteries can go for months between recharges. These batteries can last as long as the half-life of the radioactive source. efficiency to 20 percent can be achieved with this . NASA has been using radioisotope thermoelectric generators since the 1960's itself. Seebeck effect is used here.

ONE OF THE MICROBATTERIES could directly converted the high-energy particles emitted by a radioactive source into an electric current. The device consisted of a small quantity of nickel-63 placed near an ordinary sili-
con p-n junction. The emitted beta particles ionized the diodeâ„¢s atoms. 3 nanowatts could be generated with 0.1 millicurie of nickel-63. Newer ones produce electricity indirectly, like minute generators. Here the Radiation is first converted into mechanical energy and further to oscillating pulses of electric energy. They provide energy in brief pulses, but their efficiency is no less.

You can refer this IEEE article:
http://sharingmatrixfile/12804371/The-Daintiest-Dynamos.pdf
http://tahancharlie/nanosociety/course201/nanos/MPnuke.pdf
http://homepages.cae.wisc.edu/~blanchar/...dKorea.pdf