I don't think charge can do what I'm asking which is to bypass the battery and run the phone directly off the wall. I am ok if the phone reboots when the power is disrupted. On a computer, we have this setting called last known state, right? Like if the phone was on when the power was disrupted, turn it on again without using the battery when power is restored.

Basically, I want the phone to ignore that there is a battery until the battery charge drops to about 20 percent and then charge to to about 60 or 80 percent but don't use the battery at all. Only use the battery as a power source if the user switches off this dedicated mode or if the user powers on the device without external power present. Something like that.