This is my second time I change my mobile because I forget it all the night on charger.
I know there is an IC or circuit inside my phone that will disconnect the charger at fully charge,
So I brought my Multimeter and put my Lumia 520 under testing for 1 hour to see if there is anything I can build my charger on, and calculated everything; time, temperature of my mobile and my room, voltages and Amps.
and this is the result
At the beginning I was disappointment, I thought the voltage of my charger will drop down when my mobile has more power. It took two minutes to charge my mobile only 1% and there is no change in temperature (just 3*C from 61 to 100%). But after full charge the temperature decreased from 20 to 25, in twelve minutes.
I found something interesting when my battery is fully charged after 100%, the voltage changed from 5.39V to 5.50. My voltmeter is not that sensitive and I am sure its 4.50V. Anyway that little change will make a big different.
I connect my charger to Arduino and make it stop the charger when the battery is full.
Some people said it's not necessary to do that, others say that heat will not have any effect on my battery or on my mobile!
From what I know IC can't stop the charger completely, So that will damage the battery with long time!
In the same time IC will be over heated if you let it do his job for long time!
I am completely confused, I read some research about Lithium battery there is no recommended "specific point" to keep you battery on, or charging it at specific point, some research said 35, other 45, and the weirdest one was 80!
Can someone tell me if i am wrong or explain this to me!
I asked this question on stackoverflow and they said the same answer!