VRLA Battery Management System Based on LIN Bus for Electric Vehicle

A battery management system (BMS) based on the LIN-Bus was designed for the Valve Regulated Lead Acid Battery (VRLA). The VRLA BMS plays an important role as a vehicle power supply system which is part of the entire vehicle system. In order to improve the stability of various sub-systems inside the vehicle, VRLA parameters estimation, including current, voltage and temperature, are very important. However, due to lead-acid battery charging and discharging are a complex process of the electrochemical process. The VRLA BMS is consisted of a VRLA battery, a NI USB-8476 LIN transceiver manufactured by National Instruments(NI), a battery test system(BTS) and a high stability, high reliability ADuC7033 for which is high precision and rapid data acquisition ARM7 chip. The hardware design of sampling circuit, the whole VRLA BMS system structure, the software design of keil ARM7 and LabVIEW8.5 and LIN Bus communication were introduced for realtime on-line monitoring and controlling. Experimental results show that measurement is high credible and the error is within 1%. The BMS that was proposed by this paper can be used in Electric Vehicle(EV).