For the first time in years Samsung listened to the people who kept imploring it to adopt metal for its flagship smartphones. The Galaxy S6 and the Galaxy S6 edge both come with a unibody design fashioned out of metal and topped off with glass. There is one downside to this – users can't swap out the battery as easily as they could on previous Galaxy S flagships, so they'll have to make do with the 2550mAh battery pack that comes with the phone (2,600 on the Galaxy S6 edge). Previously users simply needed to pry off the plastic rear cover, swap the battery, and then snap on the cover. It was easy and could be done on the go.
While it is possible to remove the Galaxy S6's battery, the process takes more effort than many people will be willing to put in. Samsung has outlined the procedure for removing the Galaxy S6's battery in the phone's official user manual. First the screws holding the back cover in have to be removed, followed by screws that line the perimeter of the device. The circuit board has to be unscrewed and removed before the battery pack is taken out and swapped with a new one. This will only prove to be useful if the Galaxy S6's battery develops some fault and needs to be replaced. It doesn't provide the convenience of simply swapping a discharged battery with a fully charged one like users could on previous Galaxy S flagships.
Samsung cautions that these instructions are only meant for your service provider or an authorized repair agent. If you do this on your own you will probably end up voiding the warranty on your new Samsung flagship.