Research On The Equalization Charge Technology For Lithium Battery Pack In EV Application

The pure electric vehicle with the advantages of low noise and almost zero emissions, to solve energy, environmental protection and other issues of great significance. Due to the constraints of battery technology, often by battery power series group to meet the performance needs of electric vehicles. Because each single cell is different, resulting in an inconsistent state of the single battery charge during the charging process, the results greatly shorten the life of the battery pack. Therefore, in order to the effectiveness of the battery power play to the maximum to avoid the inconsistencies of single cells in the course of the performance of an effective balance charging method has great significance. Lithium-ion battery is the favor of electric vehicles with high monomer voltage and high power density characteristics. The pure electric vehicle car with the balance of power lithium battery charging technology research, but are involved in the research method is also applicable to other battery power.Understand by reading the article on battery power, battery pack performance and cause the battery pack inconsistency, analyze the advantages and disadvantages of several typical balanced circuit topology, a symmetrical distribution of energy storage inductor the new balanced charging circuitry, and balanced course of their work and the working principle of the balanced circuit has carried out a detailed analysis.Design a balanced system of hardware circuits, including the overall system hardware solutions, balanced module circuit, the main controller and related peripheral circuits, the DS2762chip as the core data acquisition circuit and the switch drive circuit, and gives specific circuit.Combined with the demand of a balanced circuit, some of the relevant parameters on the basis of lithium battery charge and discharge test have guiding significance of the balanced circuit design and control strategy. Based on the characteristics of the lithium-ion battery, a novel equilibrium plus equilibrium hysteresis control program, and gives the main program flow chart and verify the feasibility of this experiment.