Design Of Battery Management System For Electric Vehicle

Under the huge challenge of global automobile industry is facing the financialcrisis and energy, the environment, people put forward the concept of new energyvehicles. After several years of exploration, we found that the development of pure electricvehicles, electrical system of electric vehicle energy, promote the strategictransformation in the international automobile industry, formed a consensus.The battery is an important part of the new energy system. The batterymanagement system is to ensure that the power supply system can be a key technologyof the normal application. There is very important significance for the use of cost, electricvehicle energy saving and safety, the efficient use ofenergy, lengthen the service life of thebattery, the battery in the best working condition effect.This paper introduces the battery management chip OZ890and MCUC8051F040design scheme based on battery management module, the system can be applied in electricvehicles using lithium battery as power.Management module includes the hardwaresystem, software system two parts, the battery current, voltage, temperature dataacquisition, calculating the remaining energy. Also realize the balance control, batterythermal management and I2C communication, serial communication, CANcommunication and other functions. This paper first describes the status quo of batterymanagement systemand the functions to be achieved, followed by the introductionof lithium ion battery structure, principle, characteristics and the charge and dischargecharacteristics, analyzes several factors influencing the performance of lithium ionbattery. Combined with the existing SOC estimation method, the design of this systemadopted by the SOC estimation scheme. Secondly,the hardware and software design ofthe battery management system was described in details. The design of the hardwareincludes the power module design, battery information acquisitioncircuit and communication circuit. The software part of the program design, includingthe main program, the initialization program, SMBus communication program design andCAN interrupt.