The task of this master thesis is to realize a continuously operating passive balancing system for 6 cells in series including cell condition monitoring and protection circuits. For this system, sensors for voltage and temperature measurement are chosen and installed, protection measures (over-temperature, overvoltage) are installed as well a control input for remote turn-off of the balancer. Distributed power supplies are established and operating status of the entire system is displayed. Finally, the entire system is assembled, commissioned, and tested in laboratory. Voltage equalization for battery pack is evaluated. The balancing system loads cells that exhibit a cell voltage being 0.05 Volts or more over average cell voltage by a moderate current until the overvoltage falls under a defined threshold.