">100 high-rate cycles at 40% depth of zinc discharge at “an energy content competitive with lithium-ion batteries”." is the problematic part.
"Nickel-zinc alkaline is seen as a less fire-prone alternative to lithium-ion cells, which have been banned for some US military applications, according to NRL."
So they now have a battery that works with a few hundred cycles with density close to that of Li-Ion that won't explode. It may not replace Li-ion in your vape stick but still sounds like a win for the emergency lights in the armory of a battleship (for example).
The battery will long be dead by the time they'll need it.