Review on 🎮 High Capacity Rechargeable Battery Pack for Xbox One/Xbox One S/Xbox One X/Xbox One Elite Controllers - 2800mAh Replacement Xbox Battery (1 Pack) by Kyle Kriglstein

I used to buy a charger with batteries and they worked great so I bought a few more. Also, I see some of the negative reviews complaining about not charging the batteries in the controller. Unfortunately, the XBox controllers are designed that way. If you open the battery compartment and look from the side, you will see 4 pins in the middle of one side. These contacts must be used to charge the battery in the controller. And almost everywhere, all backpacks charged this way are terrible. They have a small capacity and don't last long. If you buy a battery that uses the main battery contacts on either end of the compartment (i.e. they look like regular AA batteries, or in this case like two batteries connected together) they will not charge in the controller. None of them will. This is how the controls work.