The Infinite Battery is an implementation by Galacticraft that is only accessible in Creative Mode.
The Infinite Battery is used exactly the same way as a normal battery would be used, the only difference being the Infinite Battery never runs out of charge. Since it does not need to be recharged, it makes testing systems much easier and can be used to simplify power systems when building in Creative Mode!
The Infinite Battery cannot be crafted. It is only available in creative mode.