Abstract: A method for charging a battery, which includes the steps of acquiring real-time information about the battery; receiving on-site input from a user, the on-site input comprising at least one of a user available time in which the battery is to be charged and a target State of Charge (SoC) to which the battery is to be charged; by using a capacity charging model of the battery, calculating a charging current for the battery based on the on-site input and the real-time information; charging the battery using the calculated charging current during a charging period to fulfill the user's energy requirement; and calibrating the capacity charging model based on information of the battery gathered during the charging period. The invention provides an adaptive battery charging method and system that decides an optimal charging current for batteries in view of on-site user commands inputted to the battery charger.