Patent attributes
A method is provided for balancing a battery pack including a plurality of battery cells connected in series, wherein each battery cell is associated with a resistor which is connected in parallel with the battery cell and wherein each of the resistors is coupled in series with a controllable switch which is connected to a control unit. The method includes selectively closing and opening the switch so as to initiate discharging of the corresponding battery cell, thereby balancing the battery cell in relation to other cells of the battery pack. Furthermore, the method includes a) defining a control variable indicating, for each switch, an open or closed condition, b) determining a cost based at least on the current losses of the battery pack resulting from the switch being controlled according to the control variable, repeating steps a) and b) a predefined number of times, d) selecting a control variable which results in the cost being minimized, and e) initiating the balancing based on the selected control variable. A system for balancing a battery pack is also provided.
