Research Of Charging Management System To Electric Vehicle’s Lithium Battery On The Mode Of Replacement

In the research and development of electric car, power battery and its management system research holds a very important position. The performance of the electric vehicle depends on its power battery performance. So, key factors are the battery charge and discharge properties. Therefore, it needs to charge the battery process and influence factors in the analysis and research based on this charge and discharge management. Replacement mode of battery is the mode of sustainable development, The so-called’ Replacement mode of battery", when the electric car drove into the battery charging station, does not need to stop there take a long time for charging to the electric vehicle with external power source. And it is only need to change a group charging full of power batteries use a few minutes, saving wait time in line to charge. There is a strong market competitive compared with the traditional power cars.This paper according to the characteristics and charging principle of lithium batteries, on the basis of reading large documents, analysis concretely to battery management system for present study status of home and abroad. This paper established the research contents based on the advantages and disadvantages of battery management system study. And a new management system of lithium batteries in replacement mode to the electric vehicle is proposed, the main work includes the following parts:1. Combined with the structural characteristics, the basic principle and technical parameters of single lithium batteries, this paper analyzes the influence factors impacting to the lithium ion battery, and studying concretely aspects of security features to charging, discharge, flow and thermal to monomer li-ion batteries, in order to provide theoretical basis for lithium battery support to the charge control.2. It is get problems, according to analysis and research concretely to the common charging mode to charging way of battery based on the voltage combine with monomer battery theory, and puts forward the charging mode of battery management cooperate with charging motor, then designs the structure of battery system circuit, the main including voltage detection module, temperature detecting module, electric current detection module and battery SOH detection.3. The existing problems and advantages are found,according to analyses equilibrium of dissipation and dissipative now. A kind of dissipation type equilibrium solution is designed for balance to batteries’consistency, and analysis detaily equalization circuit principle, MOSFET drive circuit and balanced process, etc. Then, designing human-machine interface LabVIEW for the hardware and software debugging.4. Estimating parameter for SOH combined with the kalman filter approach SOC estimation. After analyzing the factors influencing the SOH of the battery and get out the two state variables—the internal resistance of the battery and the battery rated capacity, a reduction Dual-EKF algorithm is proposed for state variables estimation. The approach reduces the complexity of the algorithm, the simulation results demonstrate these advantages.