Battery management system and cell balancing method

A battery management system (20) for a battery (10) comprising a plurality of cells (10-1, 10-2, 10-3, 10-4) comprises a balancing circuit (22) including a resistance corresponding to and positioned adjacent each cell; a measurement circuit (21) configured to measure a voltage and a temperature of each cell; and a selection unit (25) configured to select a high voltage cell for balancing, the high voltage cell having a voltage higher than the other cells, and to select a low temperature cell having a temperature below a threshold. The battery management system is configured to discharge the selected high voltage cell through the resistance corresponding to the selected low temperature cell to increase the temperature of the low temperature cell.