车载电池包壳体力学性能分析与轻量化设计

Mechanical Performance Analysis and Lightweight Design of Vehicle Battery Pack Shell

摘要:

电池包壳体作为电动汽车的核心组成部分，起到支撑和保护电池包的作用，其整体结构的强度直接影响电动汽车的安全行驶。对电动汽车电池包壳体进行了静态、动态及模态分析。静态分析表明，电池包壳体的应力较小，远小于材料的屈服强度，电池包壳体箱底厚度设计过于保守。动态分析是在汽车极限工况下获得电池包壳体的应力和位移的分布，结果表明最大位移位于箱底。针对不同振动源下电池包壳体的振动响应特性进行态分析，结果表明针对不同路面和工况电池包壳体的前6阶模态主要表现为电池包壳体上箱盖的局部振动，频率在安全范围之内。在此基础上，对电池包壳体进行了结构优化，在电池包壳体满足强度和刚度的条件下，优化后的电池包壳体重量减少了25.54％，达到了轻量化的设计目的。

Abstract:

As the core component of electric vehicles， the battery box plays a role in supporting and protecting the battery pack. The strength of the overall structure directly affects the safe driving of electric vehicles. In this paper， a static and dynamic analysis of the battery box of an electric vehicle is conducted. The static analysis results show that the stress of the battery box is relatively small， much smaller than the yield strength of the material， and the bottom thickness of the battery box is too conservative. The dynamic analysis is obtained under the extreme operating conditions of the vehicle. The distribution of stress and displacement of the battery box show that the maximum displacement is located at the bottom of the box. A modal analysis is also performed to analyze the vibration response characteristics of the battery box under different vibration sources. The results show that the first 6 modes of the battery box for different roads are mainly manifested as the local vibration of the upper cover of the battery box. Within the safe range， according to the above analysis results， the structure of the battery box is optimized. Under the condition of the strength and rigidity of the battery box， the weight of the optimized battery box is reduced by 25.54%， achieving the design goal of lightweight.