A method for equalizing a battery module, the battery module comprising a first battery core, a second battery core, and a power management controller, the first battery core and the second battery core being connected in series, both the first battery core and the second battery core comprising at least one battery cell, the first battery core comprising a first battery chemical component and exhibiting a first open circuit potential curve, the second battery core comprising a second battery chemical component and exhibiting a second open circuit potential curve, and the first open circuit potential curve being different from the second open circuit potential curve, the method comprising: obtaining, by the power management controller, a first charging voltage of each battery cell in the first battery core and a second charging voltage of each battery cell in the second battery core, during the charging process of the first battery core and the second battery core; Judging, by the power management controller, whether a maximum value of the first charging voltage of each battery cell in the first battery core is greater than a first preset value to determine whether the first battery core enters a corresponding first fully-charged interval; judging, by the power management controller, whether a maximum value of the second charging voltage of each battery cell in the second battery core is greater than a second preset value to determine whether the second battery core enters its corresponding second fully-charged interval; if the first battery core enters its corresponding first fully-charged interval and the second battery core does not enter its corresponding second fully-charged interval, discharging the first battery core by the power management controller until the second battery core enters its corresponding second fully-charged interval; characterised by, if the first battery core does not enter its corresponding first fully-charged interval and the second battery core enters its corresponding second fully-charged interval, judging whether the maximum value of the first charging voltage of each battery cell in the first battery core is greater than a third preset value by the power management controller; and if so, discharging the second battery core by the power management controller until the first battery core enters its corresponding first fully-charged interval; if not, controlling the first battery core and the second battery core to rest for a preset time by the power management controller; after resting for the preset time, discharging the first battery core and the second battery core by the power management controller until a SOC of each battery cell in the first battery core and the second battery core enters a same state. obtaining, by the power management controller, a first charging voltage of each battery cell in the first battery core and a second charging voltage of each battery cell in the second battery core, during the charging process of the first battery core and the second battery core; Judging, by the power management controller, whether a maximum value of the first charging voltage of each battery cell in the first battery core is greater than a first preset value to determine whether the first battery core enters a corresponding first fully-charged interval; judging, by the power management controller, whether a maximum value of the second charging voltage of each battery cell in the second battery core is greater than a second preset value to determine whether the second battery core enters its corresponding second fully-charged interval; if the first battery core enters its corresponding first fully-charged interval and the second battery core does not enter its corresponding second fully-charged interval, discharging the first battery core by the power management controller until the second battery core enters its corresponding second fully-charged interval; characterised by, if the first battery core does not enter its corresponding first fully-charged interval and the second battery core enters its corresponding second fully-charged interval, judging whether the maximum value of the first charging voltage of each battery cell in the first battery core is greater than a third preset value by the power management controller; and if so, discharging the second battery core by the power management controller until the first battery core enters its corresponding first fully-charged interval; if not, controlling the first battery core and the second battery core to rest for a preset time by the power management controller; after resting for the preset time, discharging the first battery core and the second battery core by the power management controller until a SOC of each battery cell in the first battery core and the second battery core enters a same state.