Battery management method and battery management device

A battery management method is applied for a battery management device to execute state of charge calibration in a charging procedure of a battery. The battery management method includes acquiring a reference open circuit voltage value, a reference internal resistance value and a reference state of charge from a predefined table according to a temperature of the battery, acquiring a first voltage measurement value and a first current measurement value, computing a first internal resistance value of the battery based on the first voltage measurement value, the first current measurement value, and the reference open circuit voltage value, and comparing the first internal resistance value with the reference internal resistance value to determine whether to calibrate the state of charge of the battery via the reference state of charge according to a comparison result.