Batteries is an optional cutscene of the game Run 3. It is also the first and currently the only one purchasable in the Shop. (For 15 power cells) This is also the first cutscene which features the Child hiding in the background.
After unlocking permission to refer to power cells as batteries in the shop, a one-frame cutscene will show in Winter Games, part 3. It appears to be the end of a conversation between the Student and the Skater over whether power cells should be called batteries.
The Student tells the Skater that "power cells" and "batteries" mean the same thing, and everyone already uses batteries. The Skater argues that saying "power cells" sounds smarter, to which the Student responds, "Who cares about sounding smart? Just talk normally." The cutscene can be viewed again by clicking on the upgrade in the shop after it is bought.
This cutscene can also be shown again in the cutscene gallery.
If you look carefully, you can see the Child hiding on the ceiling of the level, just above the Skater and the Student. This is also the first cutscene in which the Child is shown to be hiding in cutscenes.