I wish phones would work with no battery when plugged in.
What resistor value, and where did you place the resistor to be able to boot without a battery?
If I remember correctly there are four terminals, aside from power one of them might be battery temperature which I think is mandatory. I measured the resistance on the original and mimicked it. Basically hardcoding the temperature since I don't have a battery. But I could be very wrong on this. Google it first!