90%.

Nigel

For the N scalers amongst you, the 2MM Association magazine 310   April/May 2020, page 30, has an interesting article of fitting radio control & batteries in a N scale 0-6-0 Jinty
The 2mm Scale Association

Thank you Sol, that was going to be my question….

It's an interesting concept which I think will slowly become more popular. I've been following Bluerails efforts which have now advanced as far as Dcc controlled by Bluetooth which can be run via batteries, including DCC sound

http://bluerailtrains.com/introducing-blueraildcc-by-tam-valley/

This is the link I found a while back. Micron Radio Control : Micron Radio Control
main thoughts I have is to recharge the batteries from the rail. Not all track needs to be used for that obviously but it removes the need to recharge individual locos.

Lithium batteries are "multicelled", chargers have to be capable of equalizing charging rates between the cells. When I was messing around with the Stanton system there was a PC board specifically for this.
You can get the batteries with the circuit built in. No idea whether they would charge with 12v DC.

Nigel