all of the issues stemming from charging can be solved by having bigger battery. Why cant they make device 1 or 2 mm thicker and have device survive a day long

all of the issues stemming from charging can be solved by having bigger battery. Why cant they make device 1 or 2 mm thicker and have device survive a day longer. Then I just plug it in at the nightstand and dont have to worry about yanking phone as I dont have to top up charge. No need for spare cables at your car/work/relatives.