On Sun, 9 Apr 2017 10:21:54 +0100, Roland Perry
wrote:

In message , at 10:13:10 on
Sun, 9 Apr 2017, e27002 aurora remarked:

This http://tinyurl.com/lek9qsp could have an impact on rail and
transit. It remains to be used beyond prototypes.

Where's the filler cap for topping up the snake oil?

Not snake oil, but not new, and nowhere near production-ready.

https://en.wikipedia.org/wiki/Alumin...%93air_battery

The biggest drawback is that these batteries, despite being both
lightweight and powerful, are not rechargeable. That, combined with
their currently high cost both of manufacture and disposal, makes them
impractical for any consumer use at the moment.

See also this article from a couple of years ago:

https://www.extremetech.com/extreme/...led-with-water

On a more general note, battery technology is one of the most rapidly
developing of all, and new forms of battery are common. The challenge
with all of them is to take them past the stage of proof of concept
and into the realms of economic viability.

Mark