Whether nestled in the smallest wearable or providing back-up power for the electric grid
In the realm of batteries, duration is king. Whether we're talking about the smallest wearable or a device providing back-up power for the electric grid, a battery that can provide reliable energy for longer will always outlast the competition—figuratively and literally.
The U.S. led the way in nuclear battery innovation over the past 70 years—and even developed the first battery that ran on nuclear radiation in the 1950s. But in the 21st century, China has become the undisputed champ of nuclear batteries, which make it possible to power endeavors for decades without needing to recharge. They could provide the backbone for whole industries we haven’t even invented yet, like cybernetics, which could enable a truly intelligent robot, or deep space missions that could fly us to the stars.
Earlier this year, the Chinese company Betavolt unveiled a coin-sized nuclear battery named BV100 that uses Nickel-63 as its radioactive source, yielding an estimated 50-year lifespan. But this battery isn’t just a lab innovation—it’s already being mass produced, with the intention to power technologies ranging from medical and aerospace devices to future smartphones.
For most of us, better batteries are simply a convenience, but in some cases, battery life that’s more akin to a human lifespan is crucial. We may have no hope of long-term space exploration or life-saving medical interventions without such long-term batteries, which harness energy from a radiation source. Some elements, like uranium, are radioactive, and they have unstable atomic nuclei that spontaneously lose energy. There’s more than one way to capture that energy—in the 1950s and 60s, NASA developed radioisotope thermoelectric generators that transferred the heat from natural radioactive decay into practical energy.
But now, a new generation of batteries can trap energy from beta particles, which are electrons or positrons that fly away from their atomic nuclei during radioactive decay. This acts somewhat like photons hitting a solar panel, but in this case, beta radiation is bombarding a specially designed semiconductor, and this is how Betavolt is powering its batteries. Betavoltaic batteries comprise two parts: a radioactive emitter and semiconductor absorber. As the emitter naturally decays, high-speed electrons (aka beta particles) strike the absorber. This creates an “electron-hole” pair, which generates a small-but-stable supply of usable electric current. Since beta particles can be blocked using simply a thin sheet of aluminum, betavoltaic batteries are safe.
While not producing as much power as NASA’s thermoelectric method, these “betavoltaic batteries” can provide small amounts of reliable power for possibly up to a century—or maybe even longer, depending on the half-life of the material. It may not replace the old, reliable lithium-ion battery that powers most of our gadgets. However, the betavoltaic battery’s long life—coupled with its ability to operate in extreme conditions—makes it perfectly suited for planetary rovers, deep sea sensors, and even pacemakers. Basically, anywhere you desperately want to avoid frequent battery replacement. Nuclear batteries will become even more relevant as the world continues to decarbonize while also becoming increasingly dependent on smart sensors and other internet-connected devices. Several countries are pursuing betavoltaic battery development, including China, the U.S., South Korea, and in Europe.
Betavolt isn’t the only China-based company devising nuclear battery advancements. Just last week, Northwest Normal University in Gansu, China, announced its own carbon-based nuclear battery that can last up to 100 years. Although the basis of this battery, carbon-14, is extremely rare, the South China Morning Post reported that China has a carbon-14 commercial reactor in Zhejiang. Mimicking its photovoltaic playbook for solar energy, China is building the entire supply chain for these devices within its own borders.
While China forges ahead, the rest of the world is racing to catch up. In the U.S., the Miami, Florida-based City Labs is feverishly working on betavoltaic-based microelectronics for space missions. In November 2024, the company received significant funding from the NIH to develop long-lasting betavoltaic batteries for pacemakers (thanks to their low penetration depth, beta particles can be easily shielded from the body). Instead of Nickel-63, City Labs’ battery uses tritium, which will likely provide a 20-year battery life. Following China’s lead, the company also thinks the supply chain in the U.S. could support the batteries’ production. Scalable production of tritium can happen, because national labs and companies are forging a path, Peter Cabauy, chief executive at City Lab, told Chemistry World.
City Lab actually developed the world’s first successful betavoltaic battery called the “Betacel” back in the 1970s, but the battery’s relatively limited lifespan at the
