Device and method for achieving dynamic charging and balance of battery cells and rechargeable battery device

The present discloses a device for achieving dynamic charging and balance of battery cells, and the device is implemented in a multi-cell battery pack comprising a plurality of battery cells and a battery management circuit. According to the present invention, the device is configured for monitoring a plurality of battery voltages from the plurality of battery cells. In case of a battery voltage difference between any two of the battery cells being greater than a threshold value, the device generates a plurality of balance charging currents for charging the battery cells. In which, each of the balance charging currents is calculated based on remaining charge time, battery cell's immediate battery voltage, and a rated battery capacity. Thus, in a charge cycle, one balance charging current for charging one battery cell with low battery voltage would be designed to be greater than another one balance charging current for charging another one battery cell with high battery voltage. Consequently, elimination of th