Patent ID: 7511457

Claim:
A multi-series battery control system comprising: a plurality of unit battery cells each comprised of multiple battery cells connected in series; a plurality of control ICs each comprising a control circuit for controlling a corresponding one of the unit battery cells; a main controller configured to send and receive signals to/from the control ICs via an insulation; abnormality sensing means for sending an abnormality signal, which represents the existence or the absence of abnormality of the control ICs or the battery cells, to the main controller from the control ICs, responding to an abnormality sensing command outputted from the main controller via the insulation; voltage sensing means for sending voltage signals of the battery cells, to the main controller from the control ICs, responding to a voltage sensing command outputted from the main controller via the insulation; and a plurality of balancing switches, each respectively connected to one of the battery cells of the corresponding unit battery cell, wherein the main controller includes means for sending a battery cell voltage reading command to one of the control ICs to request the control IC to read the battery cell voltages of each of the battery cells of the unit battery cell corresponding to the control IC, wherein said one of the control ICs includes means for reading the voltage of each battery cell of the corresponding unit battery cell and for sending battery cell voltage data based on the reading to the main controller and, wherein the main controller includes means for calculating a discharging time of each of the battery cells of the unit battery cell corresponding to said one of the control ICs to control the ON time of each of the balancing switches coupled to the battery cells of the corresponding unit battery cell to balance the voltages in the battery cells of the unit battery cell, and means for providing commands to said one control IC to control the ON time of each of the balancing switches in accordance with the calculated discharging time.