Research On Impact Protection And Heat Dissipation Performances Of The Vehicle Power Battery Pack Bottom Structure

In recent years,with the development of electric vehicles,the safety of power batteries has attracted widespread attention.When the car is running at high speed,the impact of foreign objects on the road surface on the power battery box under the vehicle may cause damage to the battery structure and easily cause thermal runaway and fire.At the same time,the heat dissipation performance of the power battery pack is also an important factor affecting its service safety.The bottom structure of the power battery box currently used cannot well meet the above requirements.Therefore,it is necessary to research and design a battery box bottom structure that has both excellent impact protection performance and good heat dissipation performance.Aiming at the bottom impact and heat dissipation performance of cylindrical power battery modules,this paper proposes three battery box bottom structures with excellent impact protection performance.Numerical simulation methods are used to analyze and evaluate the impact protection performance of the above structures.The heat dissipation performance is simulated and compared,which provides a new idea for the design of the bottom protective structure of the vehicle power battery box,and provides a new solution for the collision safety and thermal safety design of new energy vehicles.The main research work of the thesis includes:(1)In view of the comprehensive performance requirements for the protection and heat dissipation of the bottom structure of the vehicle power battery box,three types of bottom protection structures of the battery box with a circular core structure,a BRAS sandwich structure and a scale multi-level structure are proposed.(2)Based on the basic theory of mechanics,the mechanical response of the BRAS sandwich structure under quasi-static compression is deduced,and the influence of the thickness of the bottom plate,the thickness of the core and the number of structural layers on the impact protection performance of the BRAS sandwich structure is studied through numerical simulation.The design of the bottom protective structure of the battery box based on this type of structure provides a foundation.(3)Numerical simulation methods are used to study the heat dissipation performance of the above three structures when applied to the bottom of the battery box,and compared with the bottom structure of the traditional homogeneous plate to ensure that the bottom structure has high impact resistance and good heat dissipation performance.To ensure that the power battery pack is in a suitable working temperature range.