How to make a intelligent charger for a 3.6 volt lithion-ion battery, When i want to use it for LED light?

I made a flash light with a old 3.6 volt lithiom-ion battery. For recharging I used the mobile phone charger the battery totally dead with in 2 recharging. Again I used another battery that also died in the similar way. So I need your kind suggestion to make a true charger. Can any one guide me? Thank you - Wir

orksecurity7 years ago
Uhm... Be Careful when trying to create your own chargers for high-energy-density batteries, either Li-ion or NiMH. If you read the manufacturer's spec sheets for these, some of the advisories are truly scary -- get the current flow wrong, and not only can they explode but you can have a burning-metal fire on your hands, which is VERY hard to extinguish (about all you can do is try to keep other things from being ignited by it). Also: Remember that some of these batteries are not meant to be discharged all the way. The phone has circuitry that protects the battery by turning off when power drops below a certain point, to prevent the cells from being damaged. Your homebrew flashlight probably doesn't.