Lanx
<Prior Amod>
pretty sure in the next ishit 7 it's gonna be 95% battery, just like the newest mac airBatteries are actually usually very recent technology in smartphones if you are buying flagship phones. The problem is really that manufacturers design specific space compartments. You need more cells for more amps and that means more volume.
The only saving grace of these power hungry behemoths is that technology is getting better and more screen gives a bigger footprint to wedge more cells in.