1) nope... discharged not check battery
2) not icon only status of batery (show 0 of 4 part of batery)
3) value is around 3,5V in echternal charger or dna60
i tried batery molicell P42a(4200mah 30A)
samsung 40T(4000mah 35A)
golisi s35 (4000mah 40A)
using only MTL around 13W
if i using Escripe batery status is discharged and i pufs it shows right above 3,5V in test pufs