In order to solve the problem that electric vehicles can not replenish the power in time due to the lack of charging stations，the design scheme for the battery management system is developed. According to characteristics of lithium batteries for electric vehicles, a new data collection for the voltage, current and temperature is proposed, and aiming at the requirements for enough power for driving, a new design of GPRS/GPS-based automatically finding the properly charging stations and online queuing and booking system is also present. The system can accurately estimate the residual capacity value and automatically remind driver to add energy to facilitate the electric car life, greatly reducing the waiting time of passengers.