TrackMaster Flip-Face Toby Experiment

[Super]

You could experiment using an 'N' size battery and a holder like this which has wires and can be soldered right up to the motor. These 'N' sizes are half the size of a AAA so it may fit nicely inside there. Not sure how long the train will run on it but maybe there is enough room to place them standing up against the front of the motor and wire them in Parallel to give more storage to the 1.5v. As much as a full AAA

'N' Battery Holder