How can I recharge 3.7v Li-ion batteries from cellphones... if I have 3 of them attached in a serial array?
I'm trying to turn a cheap pc-speaker set into a battery operated set. I have a lot of 3.7 Li-ion batteries from dead cellphones and I want to solder them into a serial arrange to get 11.1v. The question is... how to recharge them? is it safe to recharge with a 12v dc adapter? any other idea?