Quote Originally Posted by Keivan View Post
that is absolutely right, I charged my battery which it took close to 24 hours and the sound is gone, thank you Tom
What are you charging with mate? The electric potential of a potato?
Do yourself a favour and get one of the smart chargers from nitecore or xtar. An i4 should have it charged in a couple of hours and you'll be able to confirm that its hitting the correct voltage.
You can just hook up a charge plug to the + and - of the charger and use it like any other charger. Or just pop the battery and plug it in.