You guys. The built-in status of the Samsung Galaxy S6's battery doesn't mean the battery is totally non-removable. All you need is your Galaxy S6, a hair dryer, tweezers, a micro Phillips head screwdriver, a spudger tool, an intimate knowledge of electrical engineering and about an hour to kill. Simple!
Our friends at iFixit say all you really have to do is eject the SIM tray, heat up the battery door, draw off the battery door with a suction cup, then separate the door with a case-opening tool, then undo 13 screws, heat up the LCD assembly, pry open the charging chip flex ribbons, pull off the front-facing camera connector, battery connector, ear speaker connector, remove the entire motherboard, then pry off the battery with a spudger tool.
The video goes on for 20 minutes, spilling out all the technical guts hidden away in Samsung's newest flagship. But aside from all those other internals, battery life is what really counts. And to be fair, this is just the way things are now when it comes to top-tier smartphones nowadays. If you want stuff to look good, you have to ditch some convenience.