The conventional automobiles are the major source for the air pollution in the world. By the deficit of the fuels and the environmental point of view, many researches focused on the electric vehicle. Electricity can be stored in economically with the help of batteries. In order to meet the demand of the vehicles, the batteries are connected in series. These series connected batteries supply higher voltage and consequently reduces losses. The battery string with imbalance voltage condition causes the potential damage to the battery and its life diminishes. Hence, the battery charging system is required to improve the life of batteries and it is necessary for equal charging and discharging of the batteries. Buck boost based charge equalizer topology is proposed to reduce voltage imbalance in the battery string. The control algorithm for that equalizer is formulated and it has been verified with the developed prototype model. Both the simulation and hardware results obtained are discussed in detail.