Looking for ideas for battery car. This loco will serve a mining operation.
Maybe a tool car?
First battery project in 20 years, new technology. Found an old one in the parts bin with a wound, servo controlled speed control.... sigh.
Go with Li-Ion batteries. 14.8 volts, 2600mAh in a 3" x 3" x 1" space. I get between 3 - 5 hours out of a pack like that depending on the locomotive. If you're running a mining loco, it would likely be small, so your runtimes would be at the upper end of that spectrum.