I have problem with my nokia
not charging from USB,, not connectible true USB
in Bulgaria there is no repair center so even in guarantee they refuse to repair this problem! Now charging with external charger batteries - 2 of them - its absurd....
start thinking about 6V accu 4 AH and if I reduce voltage to 4,17V it will be as it needs to be.
What will happen if connect ext bat charger to battery when in phone?