Tiny nuclear battery could last for decades

Since the 1900s, researchers have wanted to use radioactive atoms to create batteries with superior longevity and resistance to damage. Several prototypes have been assembled, even used on space missions, but to no avail. In a new study published in the journal Nature On September 18, expert Shuao Wang at Dongwu University, China, and colleagues increased the efficiency of nuclear battery design by 8,000 times.

First, the team used a small sample of the element americium, which is often considered nuclear waste. It emits energy in the form of alpha particles, which carry a lot of energy but are quickly lost to the surrounding environment. So the team placed the americium in a polymer crystal to convert this energy into a continuous, steady blue light.

Next, they combined the light-emitting americium crystal with a thin solar panel. Finally, they packaged this tiny nuclear battery into a millimeter-sized quartz wafer.

Wang said that in more than 200 hours of testing, the device provided a stable power supply with relatively high power and unprecedented efficiency. It also requires only a small amount of radioactive material to operate. Although americium has a half-life of 7,380 years, the nuclear battery will operate for several decades, as surrounding components are gradually destroyed by radiation.

The new battery has a greatly improved overall conversion efficiency and power output compared to previous designs, according to researcher Michael Spencer at Morgan State University in Maryland. However, it still produces much less energy than traditional devices. For example, it would take 40 billion of them to power a 60-watt light bulb.

The team is continuing to look for ways to increase the efficiency and power output of the new battery. They also want to make the battery easier to use and safer, as it contains potentially dangerous radioactive material.

“We envision our tiny nuclear battery being used to power small sensors in remote or harsh environments where traditional power sources cannot operate, such as deep under the sea, on space missions or remote monitoring stations,” said Wang.