Heat Dissipation Structure Design And Thermal Analysis Of A Pure Electric Vehicle Battery Module

With the people's requirements getting higher and higher for living environment,green water and mountains have become a beautiful vision for people.n And new energy vehicles of zero-pollution have attracted much attention.Therefore,people are increasingly demanding the long distance and high performance of new energy vehicles.As a key component,battery system,of new energy vehicles,its performance is the key factor affecting the breakthrough of new energy vehicles.The battery is very sensitive to work temperature.If the battery works in a proper temperature range,it will be able to achieve high performance.However,if the work temperature of battery is too high,the battery capacity and output performance will be degraded,even the thermal management of battery will be out of control,while it is a serious threat to driving safety.The battery pack's cooling system properly designed will help to ensure battery good work.It studies the heat dissipation structure of the battery module in this paper based on a pure electric vehicle battery system.By considering the main parameters of the battery system,it designes the series and parallel connection of the battery modules.And by comparing the current mainstream heat dissipation method with the size of the developed model and the battery capacity,it is determined that the heat dissipation mode of the battery system choose liquid cooling mode.Firstly,the heat generation mechanism and heat transfer characteristics of the lithium battery were analyzed.And the experiments are finished about the thermal characteristics of the temperature rise and internal resistance of the single cell used in the battery system.Then the numerical model of the single cell was established based on the physical parameters of the lithium battery.And the boundary conditions of the simulation model are consistent with the experimental conditions.The heating power of the battery is loaded by UDF programming.The simulation results are compared with the experimental results to verify the correctness of the established thermal model.Secondly,a module in the battery pack is taken as the research object,five different cooling pipe structures are designed in combination with the battery module.Then CFD simulation method is used to simulate the effect of five cooling pipe structures,by comparing the temperature rise,temperature difference and temperature distribution uniformity of the module,it is concluded that the single-inputand single-out serpentine cooling pipe has the best heat dissipation effect.For the single-input and single-out serpentine cooling pipe,it obtains that the envelope angle of the cooling pipe has an influence on the heat dissipation of the battery,and then the influence of the envelope angle of the cooling pipe on the heat dissipation of the battery pack is studied about the battery performance.By analyzing the range of the envelope angle,Four kinds of serpentine cooling pipe with envelope angles are combined with the loss of power consumption of the cooling pipe to analyze the temperature rise and temperature difference of the battery modules under each cooling pipe structure,and the serpentine cooling pipe with an envelope angle of 53° are obtained.Excellent cooling pipe.Finally,based on the single-input and single-out serpentine cooling pipe with an envelope angle of 53 °,the battery module in the battery system is taken as the research object,and some factors affecting heat dissipation were analyzed.The influence about battery performance are analyzed under different circumstances,such asthe four kinds of cooling medium,the temperature of the cooling medium,the flow rate of the cooling medium and the cooling medium.through simulation analysis,combined with the actual situation of the electric vehicle,it has obtained a positive impact on the heat dissipation of the battery system,and has important reference value for the development of the subsequent battery system.