system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does slapping it actually makes tv remotes work again?
gpt
The battery has a cheap metal contact head which is different from the remote not-so-cheap copper contact. The two metal will do what is called galvanic corrosion. 

microscopically, there is a thin layer of oxide on your contacts and when the battery is almost dead, that little barrier will be comparatively too much. This is more noticeable on low power devices like remotes, mouse, keyboards. A high power device will just eat the whole battery no matter what.

When you hit the remote the battery shakes inside and the movement will slide the contacts and clean off the microscopic oxide.

On at her devices the battery is installed too tight to allow this trick work, not remove and reinstall the battery will do the same effect. 

The battery is almost dead so this action is just delaying the inevitable.