Simulation Research On Heat Dissipation Structure Of Power Battery Pack

The development of new energy vehicles has become a general trend,and the continuously improved endurance,composite modern aesthetic appearance and technological sense of the interior are favored by more and more young people.Even though the technology of lithium-ion battery has been very mature,it still faces a big bottleneck in thermal management,which needs to be further studied.In a new energy vehicle such as a pure electric vehicle or hybrid electric vehicle,the entire battery pack generates a lot of heat during the long distance use.If the heat can not be discharged in time,it will affect the performance of the whole battery pack,and even lead to the thermal runaway problem of the battery,which will affect the endurance ability of the electric vehicle.Therefore,it is important to maintain the battery pack in a suitable and relatively stable temperature range.The forced air cooling method has the advantages of simple structure and no pollution,and has been used as the first choice for battery cooling in the field of new energy vehicles.For the stable operation of the vehicle,the perfect thermal management system of the battery pack is very important,and the design of the battery pack also plays a great role.This paper first describes the research background of this topic,introduced the development of lithium ion battery,heat dissipation mode,etc.By means of simulation and experiment,the battery performance of battery pack under forced air cooling was studied under different parameters,such as the selection of inlet and outlet,inlet size,inlet velocity and battery spacing.The main research progress of this paper is as follows:(1)According to the performance of the selected lithium ion battery,the heat generation mechanism analysis and simulation model construction;The model of the battery pack was built and the appropriate simulation parameters were selected;(2)It is found that the temperature rise effect and discharge time are different under different discharge rates,and the temperature distribution on the same battery is not uniform;(3)Two boundary conditions of battery modules with no air domain and with air domain are designed.It is found that the latter is more practical,and the heat dissipation effect is obviously better than the former,and the inlet and outlet are set on the battery module;(4)The position and shape of the inlet and outlet are modeled,and the opposite square mouth model is selected.The simulation analysis of different number of inlet and outlet of battery module,different arrangement mode of single battery,different wind speed,different number of fins and spoiler is carried out respectively.The simulation results show that the heat dissipation performance of phase change material is better than that of similar cooling pipe.