Inside the BV100: How a coin-sized battery generates power for decades

Betavolt’s BV100 battery generates electricity by harnessing the natural decay of nickel-63, a radioactive isotope, rather than storing chemical energy the way conventional batteries do, according to World Nuclear News. The Beijing-based company says the device can produce steady power for 50 years without ever needing to be charged or replaced.

The battery places a two-micron-thick sheet of nickel-63 between two ultra-thin diamond semiconductor converters, described by Betavolt as China’s first such module. As the nickel-63 decays, it releases fast-moving electrons, and the diamond layers capture and channel this energy into usable electric current — a process broadly similar in principle to how a solar panel converts light into electricity.

Measuring just 15 by 15 by 5 millimetres, the BV100 generates 100 microwatts of power at 3 volts, suited to low-power applications like medical implants and environmental sensors rather than consumer devices such as phones. Betavolt has said its batteries are modular, allowing multiple units to be combined to scale up total power output.

Nickel-63 was chosen partly for safety, since it decays into stable, non-radioactive copper and emits low-energy radiation that thin materials can shield.