State - Based Detection System For Lithium Battery Pack Based On

The lithium battery is mainly used in power sources and energy carrier, and in the applications, it is necessary to scientifically and effectively manage the lithium battery, moreover, the battery management system(BMS) research being also a hotspot of electric vehicle. BMS is mainly used to monitor and manage the running states of batteries on line, as well as realize various protection functions such as:preventing the battery overcharge、overload、short circuit and so on. In addition, the BMS can balance each battery, estimate the battery residual electric quantity by various parameters, diagnose each single battery health and prolong the service life of the cell.At present, Many problems about the BMS are needed to be solved. For example, the battery state of charge(SOC) estimation, battery equalization charging technology is still immature. It is the key technology for electric vehicle BMS research to estimate SOC. Therefore, the study on the BMS in the thesis, software and hardware of a lithium battery management system will be designed, and the real-time data of the battery management system acquisition fault alarm, and the basic charging protection and SOC calculation and other basic functions ares summarized, as well as, key points of various functions and technology are analyzed and compared, and last the revised SOC estimation method being proposed. Finally,the main content of the paper is listed as follows.Firstly, hardware of a lithium battery management system is designed. Then the lithium battery charge and discharge state are described and summarized, and combined Kalman filter based on the traditional SOC estimation method is used to estimate the battery charge state. In addition, an FPGA NIOS II processor-based battery management system is designed. Finally, the test data indicate that the accuracy and reliability of the BMS in the theme.