Research Of Life For Lithium Power Battery Based On Simulation Of Condition

Power battery, as the main energy source for electric vehicles, is the important part in electric vehicles. The performance of power battery directly affects the prospects of electric vehicles. Power battery with its high-voltage, long cycle life, environmental protection and many other advantages has been widely used In the field of electric vehicles.Currently, the detection of lithium battery technology is not yet fully mature. The prediction of an important parameter of Lithium SOH(State-Of-Health) has always been a problem for battery testing. In order to meet the requirements of high-voltage, battery usually in the form of module installed in the car. Electric cars usually run on a different work environment, battery will surely be the impact of different temperature, vibration and charge and discharge current, these factors will certainly affect the battery cycle life.LiFePO4 battery cells under different conditions of charge and discharge characteristics were analyzed based on the study in the internal structure and working principle in this paper. To analyze and identify factors with the battery life-related parameters after several tests, on this basis, to build electric vehicle simulation platform to simulate different conditions, to use temperature controling box to simulate the outside temperature, to use vibration test to simulate the real vehicle vibration operation conditions of different road, to control the battery's charge and discharge current to simulate the actual battery charge and discharge conditions of work, then put the battery on the simulation of charge and discharge cycle test conditions. Under the influence of various external conditions, the cycle life of battery is different. On this basis, a large number of experiments were carried on, proposed the concept of coefficient of battery capacity fading by analyzing the experiment. Establishing cycle life of battery pack model under the influence of the external environment based on a large number of experiments, and then to predict SOH of battery. Finally, the model of prediction above has high accuracy, provides a theoretical basis and method for future production and use of the battery.