What Can Be A 9V Battery Made Up Of?
It does not make a difference if it is dead or not. It should take max 3-6 hours to charge to full power even if you still have battery left behind. There is a big difference in how long it will finally. There is a standby mode when you aren't using it which most phones last up to a few days 3 max. But if you use it a lot the battery will die a lot