Researchers at DGIST led by Professor Su-Il In have made a big step forward in betavoltaic batteries. These are batteries that generate power from radioactive decay. The team reported a sixfold improvement in efficiency for perovskite-based devices. The study was published in Carbon Energy.
Why This Matters
Betavoltaic batteries can produce electricity without external charging. They last a very long time depending on the radioactive material used. That makes them useful in situations where replacing a battery is hard, like in medical implants, space equipment, or autonomous AI devices. Traditional lithium-ion batteries can run out, overheat, or need replacement. Betavoltaic batteries avoid those problems.
The challenge has been low efficiency. Older designs could not turn enough radiation into electricity to be practical.
How They Did It
The DGIST team used carbon-14 nanoparticles as the radiation source. They paired that with perovskite materials as radiation absorbers. Working with Professor Jong Hyeok Park from Yonsei University, they added methylammonium chloride (MACl) during fabrication. They also used isopropanol as an antisolvent.
These steps helped the perovskite crystals grow bigger and reduced defects inside them. Electrons produced by the beta particles could move without getting trapped. The team even observed an “electron avalanche,” producing roughly 400,000 electrons per beta particle.
The resulting battery reached an energy conversion efficiency of 10.79 percent, six times higher than previous perovskite betavoltaic batteries. It also ran continuously for more than 15 hours without performance loss.
Looking Ahead
This is the first time high-efficiency betavoltaic batteries have been shown in practice. The research could make these batteries viable for AI systems, autonomous vehicles, and spacecraft where long-lasting power is needed.
Professor Su-Il In said the team plans to continue research to make these batteries commercially available. “We want independent, long-lasting power for industries that need it,” he said.
