A battery management system, comprising: a voltage sensor configured to generate a voltage signal indicating a voltage of a battery; a current sensor configured to generate a current signal indicating a current flowing through the battery; and a control unit configured to record a voltage history and a current history of the battery based on the voltage signal and the current signal at a predetermined time interval during constant current charging of the battery, wherein the control unit is configured to: determine a differential capacity curve indicating a correlation between the voltage of the battery and a differential capacity in a reference voltage range based on the voltage history and the current history, and perform a first protection operation for the battery by comparing a first characteristic voltage of a main feature point with a reference voltage when the main feature point is detected from the differential capacity curve, wherein the first protection operation includes an operation of decreasing a reference current of the constant current charging by a first compensation current corresponding to a voltage difference between the first characteristic voltage and the reference voltage, characterized in that the control unit is configured to perform a second protection operation for the battery when an additional feature point having a second characteristic voltage that is larger than the first characteristic voltage is detected from the differential capacity curve, and wherein the second protection operation includes an operation of additionally decreasing the reference current decreased by the first protection operation. a voltage sensor configured to generate a voltage signal indicating a voltage of a battery; a current sensor configured to generate a current signal indicating a current flowing through the battery; and a control unit configured to record a voltage history and a current history of the battery based on the voltage signal and the current signal at a predetermined time interval during constant current charging of the battery, wherein the control unit is configured to: determine a differential capacity curve indicating a correlation between the voltage of the battery and a differential capacity in a reference voltage range based on the voltage history and the current history, and perform a first protection operation for the battery by comparing a first characteristic voltage of a main feature point with a reference voltage when the main feature point is detected from the differential capacity curve, wherein the first protection operation includes an operation of decreasing a reference current of the constant current charging by a first compensation current corresponding to a voltage difference between the first characteristic voltage and the reference voltage, characterized in that the control unit is configured to perform a second protection operation for the battery when an additional feature point having a second characteristic voltage that is larger than the first characteristic voltage is detected from the differential capacity curve, and wherein the second protection operation includes an operation of additionally decreasing the reference current decreased by the first protection operation. determine a differential capacity curve indicating a correlation between the voltage of the battery and a differential capacity in a reference voltage range based on the voltage history and the current history, and perform a first protection operation for the battery by comparing a first characteristic voltage of a main feature point with a reference voltage when the main feature point is detected from the differential capacity curve, wherein the first protection operation includes an operation of decreasing a reference current of the constant current charging by a first compensation current corresponding to a voltage difference between the first characteristic voltage and the reference voltage, characterized in that the control unit is configured to perform a second protection operation for the battery when an additional feature point having a second characteristic voltage that is larger than the first characteristic voltage is detected from the differential capacity curve, and wherein the second protection operation includes an operation of additionally decreasing the reference current decreased by the first protection operation.