A battery management circuit, comprising a first charging channel, and a communication control circuit, the first charging channel being configured to receive charging voltage and/or charging current from a power supply device and charge a battery by applying directly the charging voltage and/or charging current to the battery, and the battery comprising a first cell and a second cell coupled in series; the communication control circuit being configured to communicate with the power supply device to make magnitude of the charging voltage and/or charging current from the power supply device match a current charging stage of the battery, when the power supply device charges the battery through the first charging channel; and characterized in that: the battery management circuit further comprises a Cuk circuit; the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make the first cell and the second cell transfer energy through the Cuk circuit to equalize voltage of the first cell and voltage of the second cell, when the voltage of the first cell and the voltage of second cell are nonequalized; and the communication control circuit is further configured to adjust duty cycle of the drive signal to adjust current in the Cuk circuit, during working of the Cuk circuit, wherein the communication control circuit is configured to decrease the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are supplying power and wherein the communication control circuit is configured to increase the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are not supplying power, the duty cycle being greater when the first cell and the second cell are not supplying power than when the first cell and the second cell are supplying power. the first charging channel being configured to receive charging voltage and/or charging current from a power supply device and charge a battery by applying directly the charging voltage and/or charging current to the battery, and the battery comprising a first cell and a second cell coupled in series; the communication control circuit being configured to communicate with the power supply device to make magnitude of the charging voltage and/or charging current from the power supply device match a current charging stage of the battery, when the power supply device charges the battery through the first charging channel; and characterized in that: the battery management circuit further comprises a Cuk circuit; the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make the first cell and the second cell transfer energy through the Cuk circuit to equalize voltage of the first cell and voltage of the second cell, when the voltage of the first cell and the voltage of second cell are nonequalized; and the communication control circuit is further configured to adjust duty cycle of the drive signal to adjust current in the Cuk circuit, during working of the Cuk circuit, wherein the communication control circuit is configured to decrease the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are supplying power and wherein the communication control circuit is configured to increase the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are not supplying power, the duty cycle being greater when the first cell and the second cell are not supplying power than when the first cell and the second cell are supplying power. the battery management circuit further comprises a Cuk circuit; the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make the first cell and the second cell transfer energy through the Cuk circuit to equalize voltage of the first cell and voltage of the second cell, when the voltage of the first cell and the voltage of second cell are nonequalized; and the communication control circuit is further configured to adjust duty cycle of the drive signal to adjust current in the Cuk circuit, during working of the Cuk circuit, wherein the communication control circuit is configured to decrease the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are supplying power and wherein the communication control circuit is configured to increase the duty cycle of the drive signal when the first cell and the second cell are in a state where the first cell and the second cell are not supplying power, the duty cycle being greater when the first cell and the second cell are not supplying power than when the first cell and the second cell are supplying power.