Miniature nuclear battery lasts 20 years

Technology News | August 26, 2020

By Nick Flaherty

Based on an original patented microchannel 3D structure of a nickel beta-voltaic element, the nuclear battery is three times smaller than previous designs with a specific power that has been increased by 10 times, and a cost cut by 50 percent. In this case, the radioactive element is applied on both sides of the so-called planar p-n junction, which simplifies the cell manufacturing technology, as well as the control of the reverse current that “steals” the battery power.

The special microchannel structure, say the scientists, provides an increase in the effective conversion area of the beta radiation by 14 times, which results in an overall increase of current from the nuclear battery.

“The output electrical parameters of the proposed design were: short-circuit current IKZ — 230 nA /cm² (in the usual planar construction — 24 nA), the final power — 31nW/cm², (in the planar one — 3nW),” says Sergey Legotin, Associate Professor of the Department of Semiconductor Electronics and Physics semiconductors at NUST MISIS. “The design allows to increase the efficiency of converting the energy released during the decay of a ß-source into electricity by an order of magnitude, which in the future will reduce the cost of the source by about 50% due to the rational use of an expensive radioisotope.”

At the same time, say the scientists, the development will make it possible to increase the specific power by an order of magnitude, due to which the weight and dimensions of the batteries based on them will decrease three times while maintaining the required output power level. The battery can be used in several functional modes:

as an emergency power supply and temperature sensor in devices used at extreme temperatures and in hard-to-reach (or completely inaccessible) places
- in space
- under water
- in high-altitude areas

A battery based on beta-voltaic cells, say the scientists, has great potential since the demand for reliable batteries with a long service life is growing in all industries. Taking into account the latest development’s unique characteristics — small size and safety — the scientists believe it will be able to occupy a significant share of the power supply market.

The developers are completing the procedure for international patenting of the invention.

For more, see “Development of betavoltaic cell technology production based on microchannel silicon and its electrical parameters evaluation.”