Eriksholm: The Stolen Dream

A short while into the game, you must lower a bridge, and that requires powering it up. You enter a garage that has some controls on a gangway, you operate the controls to use a crane to pick up a battery pack that has four cells. The pack is in the train, so you use the crane to pick it up and drop it in the bay that has the end of the power cable. This was the bay second from the garage doors, I assume it's the same for everyone!
Once you drop the pack in to the back, the doors open and bloop.

PS: I REALLY wish you could paste an image in here and not just Xbox images. :)