Which way does the battery go?

This seems like a dumb question, but is the battery flat side supposed to be facing up? I can’t tell if my battery is dead or I’m doing something wrong. The TurnTouch team should at least have a series of YouTube videos to cover this kind of stuff. Is there a pdf of the manual available somewhere?

If you turn it over does it fit or work?

The plus side up. In other words, the negative side should touch the board.