What is the difference between slow and fast charge?
Yes, the amperage your charging at determines charging time. The higher the amperage, the faster it charges. Your battery is rated in mAh or milliamp hours. One Ah means the electric charge transferred by a steady current of one ampere for one hour. A mAh would be 1/1000th of an amp for one hour. If your battery is a 1500mAh battery it means 1.5 amps for one hour. This charge current should not exceed the rating of the battery. It would cause possible excessive heating and possible a fire or explosion, especially on newer more volatile batteries like lithium polymer batteries. The life of the battery charge when fully charged will be similar no matter how you charged it, but slower, lower amperage charges will maintain your battery better than quicker, higher amperage charges and help extend it's life to its potential.
I think it's the amount of Amper... Some laptot offer only 100mA on USB (slow Charge) instead Desktop PC can offer 500mA (fast Charge). The life time of the battery is the same (i suppose) with the fast or with the slow Charge. the difference is in power consumption.
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