Prediction system of electric vehicle battery charging time

Disclosed is a system for charging a battery for an electric vehicle. The system includes: a distinguishing step of identifying express charging or slow charging; a measuring step of measuring a value of reference currents, stored in advance, after calculating an amount of electric currents to be charged when slow charging is identified; and a first calculation step of calculating expected time for slow charging by using the amount of electric currents to be charged and a current value of previous charging.