Re: Charging BL-5J battery outside the phone.
 

Your battery will charge when the phone is turned off.

https://raw.githubusercontent.com/NI...umentation.txt

Re: Charging BL-5J battery outside the phone.
 

I am connecting my turned off phone to wallcharger. Then almost immediately NOKIA logo is shown on the screen (without backlight). After about 10 seconds LED goes constantly red (not flashing like during normal charging). Then, after couple of minutes, logo disappears and LED goes off. Battery is still uncharged.

Re: Charging BL-5J battery outside the phone.
 

Try to connect your phone to the wallcharger without battery. Place the battery back. If the phone doesn't turn on again just let it recharge for a few hours.

Re: Charging BL-5J battery outside the phone.
 

I've tried this method. The phone did not turn on, no light, no logo. I disconnected it after about half an hour, but battery is still dead. How long should I charge it and what percentage of capacity can I obtain? Could you please describe me in a few words what is happening when this method is used.

Re: Charging BL-5J battery outside the phone.
 

All Lithium batteries have the same voltage. Some say 3.6, others 3.8, but underneath it is all the same technology. 3.7 is a median and the exact figure depends on how you calculate it; a fully charged Lithium battery has something like 4.1V.

If "the other phone" takes BL-5J then there is nothing to speculate. The contacts are already set up for you. The universal one I posted a link to can figure it out by itself, even if you reverse the battery. There are other ways but if you have to ask, then you better stick to tried and foolproof ways like those already mentioned. DIY can be dangerous in the hands of an amateur.

Re: Charging BL-5J battery outside the phone.
 

Dead on the money.
It is what I would suggest.
I have a few different types of chargers.
My uboc has replaced them all.
http://www.ebay.ca/itm/UBOC-Universa...4AAOSw7NNT3lN3

Re: Charging BL-5J battery outside the phone.
 

If your battery is dead I'd suggest a couple of hours to get a decent charge back using an external charger.
a half hour might not cut it.
If your battery still doesn't want to comply...
perhaps it is the fact the external charger is faulty....
possibly..
but I'd guess..
I'd say you got a very dead battery on your hands.

Re: Charging BL-5J battery outside the phone.
 

I have external charger for my DSLR Nikon. It has output voltage 7.4V and current 0.9 A. Can I use it to charge BL-5J battery (3.7V) ?

Re: Charging BL-5J battery outside the phone.
 

No. 10 chars

Re: Charging BL-5J battery outside the phone.
 

I've found yesterday in service manual for Nokia N900 information as follows:

"If a USB cable is connected before a battery, charging is not started. The USB cable and battery must then be removed before charging is started."

So this method of charging is useless, because nothing is charged.