Proper source: https://www.jaif.or.jp/en/news/7426

This has nothing to do with uranium as a nuclear material. Depleted uranium is what you get when you remove the radioactive isotopes of uranium from natural uranium; the uranium is not being used as an energy source. This is just a rechargeable battery.

This battery is taking advantage of uranium's chemical properties, in a somewhat similar way to a lead acid battery. Unfortunately uranium is fairly toxic chemically – like lead – so this is probably not a great idea for applications where you can't guarantee proper disposal.

But nearly 100% of lead acid batteries are recycled, so that might be feasible.