Power Battery Pack Forming Design Based On Thermal Management For Electric Vehicles

In the rapid development new energy automotive industry today, electric vehicles,as an important development direction of the automotive industry, has been widelyconcerned. The power battery pack the is the only power source of electric vehicles, theperformance of the power battery pack forming seriously restricts the performance ofelectric vehicle. After the power batteries forming into a pack, the performance willhave different degrees decline compared with single cells. Aiming at the problem ofpower battery performance decline after pack forming, this dissertation conducts thebattery pack forming design study for electric vehicles from the perspective of batterypack thermal management.Battery thermal management includes two aspects: the battery module temperatureequalization and the overall battery pack thermal dissipation. Beginning with these twoissues, this dissertation adopts the method of combining the battery discharge thermalmeasurement test and the computational fluid dynamics numerical simulation toconduct a preliminary battery pack forming design.This dissertation designs and conducts two set lithium-ion battery discharge heatcharacteristic tests, including the lithium-ion battery module indoor discharge test andvehicle bench battery discharge test, through the comparison of test results with thetemperature data acquisition and processing, discusses the need for thermalmanagement of the battery pack.To carry out the battery discharge thermal effects numerical simulation, thisdissertation establishes the battery thermal mathematical and physical model andcalculates the required equivalent model thermal parameters for solving batterytemperature field and the battery thermal generation rate, and proves the reliability ofthe models through the comparison of the battery discharge thermal test and thephysical model numerical Simulation results.To improve the two issues of the battery pack thermal management, thisdissertation proposes a battery module temperature equilibrium approach and designs abattery pack overall thermal dissipation structure, and finally obtains an idealtemperature equalization measure and an overall thermal dissipation structure programthrough the numerical simulation and optimization improvements.This dissertation conducts the design of the battery pack forming based on the design of the thermal management and power connection design, and proves thereliability of the thermal management solution through the numerical simulation.Meanwhile, this dissertation puts forward a small electric vehicle chassis frame designscheme with a removable battery pack, to complete the battery pack forming purposes.