DISCHARGE VOLTAGE GRAPH PREDICTION METHOD AND BATTERY SYSTEM USING THE SAME

A method for predicting a constant current discharge graph for a battery cell according to one feature of the invention includes: measuring a first time required for the battery cell voltage to decrease to a first discharge limit voltage by a first constant current discharge; measuring a second time required for the battery cell voltage to decrease to a second discharge limit voltage by a second constant current discharge; and calculating a proportional constant and an index parameter in the relationship between the constant current and the discharge time during a discharging based on the first constant current and the first time, and the second constant current and the second time. The first discharge limit voltage is a voltage obtained by subtracting the first voltage drop due to the first constant current and the internal resistance of the battery cell from the discharge reference voltage when the discharge current is 0, and the second discharge limit voltage is a voltage obtained by subtracting the second voltage drop due to the second constant current and the internal resistance of the battery cell from the discharge reference voltage.