I am new to G scale railroading and have been researching battery power. On YouTube there are a couple of videos that show a trailing battery car with a lithium ion power tool battery that is powering 1 or 2 g scale locomotives. It would seem to be a simple connection. My questions are "what is the maximum voltage? " and “do I need to install a fuse ?”
You do have a simple question, but the situation is more complicated.
The simple answer is that in G scale, most locos can take up to 24 volts.
Yes a fuse is a good idea.
But you need a way to control the speed and direction, or are you just going to leave it running 200 scale miles per hour at max voltage? [:P]
Greg