Before installing, you should have a charged VEX IQ Robot Battery. See this article for information about how to charge the battery.
Install the Robot Battery
Slide the Robot Battery into the VEX IQ Robot Brain and listen for a click that indicates the Robot Battery has been inserted correctly and completely.
Remove the Robot Battery
Squeeze the latch at the end of the Robot Battery and pull it out of the Brain.
NOTE: Pushing on the Robot Battery from the other end helps in removing it.
NOTE: The Robot Battery should always be removed from the Brain if it is going to be stored for longer than two weeks.