A battery management system, comprising: a battery pack comprising a plurality of cells (CELL13, CELL14, CELL15) in series, each cell having a corresponding cell voltage; a cell balancing unit adapted to balance the cell voltages; a cell selecting unit adapted to establish an electrical connection to any selected one of the cells, the cell selecting unit comprising a set of cell selection switches (SH1, SL1; SH2, SL2; SH3, SL3; SH4, SL4) coupled to each end of the cells wherein one set (SH1, SH2, SH3, SH4) of the set of cell selection switches has one end electrically connected to one end of a cell and the other end electrically connected to a first output terminal, and the other set (SL1, SL2, SL3, SL4) of the set of cell selection switches has one end electrically connected to the one end of the cell and the other end electrically connected to a second output terminal, wherein the cell selection switches may be turned on and off so as to selectively select one or more given cells; a control unit adapted: - to measure the cell voltages, - to control the operations of the cell balancing unit and the cell selecting unit, - to prevent a cell selected for voltage measurement and the cells directly electrically connected to the selected cell from being balanced while the cell voltage of the selected cell is being measured, and - to simultaneously measure the cell voltage of the selected cell and balance a cell non-directly adjacent to the selected cell. a battery pack comprising a plurality of cells (CELL13, CELL14, CELL15) in series, each cell having a corresponding cell voltage; a cell balancing unit adapted to balance the cell voltages; a cell selecting unit adapted to establish an electrical connection to any selected one of the cells, the cell selecting unit comprising a set of cell selection switches (SH1, SL1; SH2, SL2; SH3, SL3; SH4, SL4) coupled to each end of the cells wherein one set (SH1, SH2, SH3, SH4) of the set of cell selection switches has one end electrically connected to one end of a cell and the other end electrically connected to a first output terminal, and the other set (SL1, SL2, SL3, SL4) of the set of cell selection switches has one end electrically connected to the one end of the cell and the other end electrically connected to a second output terminal, wherein the cell selection switches may be turned on and off so as to selectively select one or more given cells; a control unit adapted: - to measure the cell voltages, - to control the operations of the cell balancing unit and the cell selecting unit, - to prevent a cell selected for voltage measurement and the cells directly electrically connected to the selected cell from being balanced while the cell voltage of the selected cell is being measured, and - to simultaneously measure the cell voltage of the selected cell and balance a cell non-directly adjacent to the selected cell. - to measure the cell voltages, - to control the operations of the cell balancing unit and the cell selecting unit, - to prevent a cell selected for voltage measurement and the cells directly electrically connected to the selected cell from being balanced while the cell voltage of the selected cell is being measured, and - to simultaneously measure the cell voltage of the selected cell and balance a cell non-directly adjacent to the selected cell.