‘You can’t have fires on boats’: Navy research on safer zinc batteries moves forward

WASHINGTON (c4isrnet): The U.S. Naval Research Laboratory is exploring future potential uses for its zinc-based batteries that provide a safer, reusable alternative to other types of batteries.

In particular, the zinc-based batteries would provide the Navy an option instead of rechargeable lithium-ion batteries that are fire prone and struggle to gain safety approval.

The lab’s battery, moving out of technology readiness level one, uses a 3-D sponge of the metal, making the battery rechargeable.

“We’re starting to move out of the really fundamental chemistry portion of it and moving towards, ‘OK, can we make devices? Can we have applications that need specific current or voltage? And then can we design batteries specifically for that? So that starts to move us up the manufacturability- and technology-readiness level into things that are either being tested or deployed,” said Ryan DeBlock, a researcher with the surface chemistry division at U.S. Naval Research Laboratory.

The sponge, a “porous network of metallic zinc,” is only 30 to 40 percent dense, according to DeBlock, who spoke with C4ISRNET at the Navy League’s Sea-Air-Space conference.

“What this does is it takes the current that you’re applying to the battery, and instead of spreading it on a flat surface, you’re spreading out all over that internal sponge area,” he said. “This allows us to actually use the zinc batteries in a rechargeable way instead of a one-and-done like a AA battery.”

The zinc-based batteries have several advantages, he said. Zinc is inexpensive and widely available, so the batteries cost less and don’t rely on more complex regional supply chains, whereas the lithium for lithium-ion batteries is sourced largely from South America. Another major advantage is that the research lab’s battery isn’t flammable.

“You can’t have fires on boats or in subs,” he said.

The zinc batteries are far more environmentally friendly than lead and can provide “a lot more energy” per weight or volume, DeBlock said. Further in the future, the batteries can also help with grid battery storage.