DARPA seeks radioactive battery that could run a laptop for months — if you don’t mind the radiation

Big ambitions, small package

It has been reported that DARPA has awarded a $5.2 million contract to Avalanche Energy to help develop a high-power radioactive battery under its Rads to Watts program. The goal is eyebrow-raising: more than 10 watts per kilogram — enough, allegedly, to power a laptop-class device for months from a battery weighing only a few kilograms. Sounds like a dream for field ops and deep-space missions. It also sounds like something out of a sci‑fi prop shop.

How it would work

Avalanche will reportedly build solid‑state, micro‑fabricated alphavoltaic cells — devices that convert alpha particles into electricity — rather than the beta-based betavoltaics used in pacemakers and small sensors. Alpha sources can be far more energetic, but they’re also more hazardous to humans; luckily, DARPA’s brief focuses on space and hardened defense platforms, where shielding and distance help. For context: Curiosity and Perseverance use radioisotope thermoelectric generators that weigh about 100 pounds to produce ~110 watts — roughly 2.5 W/kg. DARPA’s 10 W/kg target would be a major leap.

Why Avalanche?

Avalanche pitches this as complementary to its fusion work. It has been reported that the company’s fusion devices will generate alpha particles and neutrons that could both produce the radioisotopes needed for these batteries and validate degradation‑resilient microchips that capture decay energy. In short: make the fuel and the tech in one shop. Neat supply‑chain synergy, if it pans out.

Trade‑offs and the human angle

Think convenience: months of untethered power, no recharging, no hot-swap battery packs. But there’s a visceral reaction here — radioactivity as the cost of convenience. Who wants a glowing brick in their backpack? Maybe not hikers. Satellites and soldiers? Different story. It has been reported that DARPA wants the package hardened for space and extreme environments, which shifts the focus from consumer angst to mission capability. Either way, this is a reminder that as we chase ever‑longer runtimes, the compromises get stranger.

Sources: The Register