Review on Xbox One Controller Charger and Rechargeable Battery Pack - YCCTEAM | Compatible with Xbox One, Xbox One X, Xbox One S, Xbox One Elite Controller | Xbox One Charging Station with 2 x 1200mAh Rechargeable Batteries by Mary Mabior

Bought for my son for Christmas, right out of the box they worked fantastic! It took the whole day. He charges them overnight and he and his friends can play for up to 20 hours on each controller! Although they are brand new and therefore work great, I expect the run time to decrease over time. I will update when this happens. Otherwise, they're easy to install by simply snapping them into the battery compartment on the back of the controller, and you're done!