Uranium Battery – an Innovation Straight Out of a Science Fiction Lab?

Sounds like science fiction? Maybe. But it really happened:
Scientists from the Japan Atomic Energy Agency (JAEA) have developed a working prototype of a battery that uses depleted uranium – a material traditionally regarded as a problematic byproduct of nuclear fuel production.

And although the technology is still at the lab stage, it could pave the way for a whole new direction in energy storage – especially for energy from renewable sources.

What’s the deal with uranium?
Depleted uranium is a byproduct of the uranium enrichment process – it’s the “less active” sibling of the U-235 isotope used in nuclear reactors. There are hundreds of thousands of tons of it worldwide – Japan has 16,000 tons, and the U.S. over 750,000 tons. Until now, it’s been used in military and medical applications. Now, it might power batteries.

The JAEA team created a flow battery in which depleted uranium serves as the active material in the negative electrode electrolyte, while iron plays the role on the positive side. In simple terms: two tanks with liquid electrolytes flow through cells, and the difference in potential generates electricity. Their prototype operated stably for 10 charge/discharge cycles, delivering 1.3 volts – comparable to a classic AA battery.

Why do this at all?
Mainly as an alternative to lithium-ion batteries, which require scarce resources. The uranium battery could serve as a stationary energy storage system, e.g., for wind or solar farms, where energy delivery isn’t always steady.

Another big plus: the material is already available. Instead of making something from scratch, we reuse what’s already stored as nuclear waste.

Sounds promising, but…?
There are a few caveats:

Radioactivity – Even though depleted uranium is relatively safe, it still requires shielding, safety protocols, and specialized transport.

Cost – Existing technologies like Li-Ion and commercial flow batteries already benefit from economies of scale. New solutions must be extremely competitive to break into the market.

Scale – The prototype was small. The team is now working on a version using 650 tons of uranium with a 30 MWh capacity – enough to power ~3,000 Japanese homes for one day. But that’s still just a concept.

Is there market potential?
If countries investing in nuclear power look for ways to reuse their waste, and continue to push for renewables, uranium batteries might become an attractive option – especially in areas where lithium is scarce.

But it won’t happen overnight. For now, it’s an interesting experiment – and that’s a good thing. Even if uranium batteries never end up in our homes, they might inspire new directions in energy storage design.

Source: spectrum.ieee.org