I just read a number of responses about the battery vs transformer thing and wow. I am new to this forum and not even sure where to begin or what section I sould be sending messages in. So I'm here and here I go. Iam going to do the battery thing. I've just started about two month ago with G scale and look forward to spring to building the "garden". My question is: what voltage and amphour battery should I be looking for? Is there a max volt and Ah rating that shouldn't be exceeded? Has any one used lap top li-ion batteries in their loco's? Some of those lap top batteries look like they would fit in the boiler of the steam engines. I would like to be able use one size, one brand, one voltage rated battery (or serires of batteries) for any and all the loco's I would use. Yes, I realize thats not likely to happen and should just figure that if its batteries then i will have mulitple styles, types, shapes, etc. along with as many chargers. Some addition facts (statments): I do want to put the batteries in the loco's not trailing cars, Ii have been looking at batteries on line for weeks primalry looking for size and shape to fit in loco's, then volt and amps, Im not hooked on any one type of battery either. I have found 12v SLA's that would fit in my U-boat (2 side by side in the long hood section) as well as a lap-top style li-ion that's almost the same size. I also intend to either invest in Airwire or Locolinc for the R/C part of this. Any thoughts and input would be appreciated.