There are provided a battery management apparatus, a battery management method and a battery pack. The battery management apparatus includes a sensing unit configured to detect a current, a voltage and a temperature of a battery, and a control unit. The control unit determines a first candidate value for a state of charge (SOC) of the battery using ampere counting. The control unit determines a Kalman gain and a second candidate value for the SOC using an extended Kalman filter. The control unit determines the first candidate value as the SOC when a difference value between the first candidate value and the second candidate value is larger than a threshold value. The control unit adjusts a ratio of second process noise to first process noise in the extended Kalman filter based on a first component and a second component of the Kalman gain.