System for controlling voltage balancing in a plurality of litium-ion cell battery packs and method thereof

Disclosed are system and method for adjusting a voltage balancing of cell in a lithium ion multicell battery pack. [0002] The battery balancing system according to the invention comprises a plurality of multicell battery packs comprising a first CPU for reading terminal voltages of cells in a master module and a slave module; a system controller for collecting and calculating cell related data from the multicell battery packs; a second CPU installed in the system controller and for receiving data of all cells in the multicell battery packs to provide a balancing target value required for each of the battery packs; and a DC-DC converter for controlling a direction of current flowing to each cell, based on the target value, to adjust a voltage balance.