Will a high current destroy my smartphone battery? I know very little about batteries, but I'm getting really annoyed at having to wait 8 hours for my phone battery to charge (it's a 6 year old smartphone). So I was thinking of raising the 2.1A output of the charger to 3.1A without raising the voltage. I'm willing to experiment, I mean, this is so old I'm not afraid to break it. But first, I want to hear some possible theoretical answers. The specs of my battery are: Li-ion 3.7V 1500mAh 5.6Wh. My questions are: any chances of this destroying the battery? Or is there usually like a circuit that stalls the current at a specific level on smartphones and instead of destroying the battery I destroy the circuit and render the phone unable to charge the battery, but still be able to charge the battery with an off-phone charger?