电动汽车电池箱轻量化设计

Lightweight design of electric vehicle battery box

对电池箱进行轻量化设计时,为选择合适的轻质材料,使其与电池箱不同位置板件进行匹配以充分发挥材料性能,采用基于CRITIC权重的TOPSIS法和正交试验的方法。建立了电池箱常用金属材料各项性能的决策矩阵,使用基于CRITIC权重的TOPSIS法进行标准化处理,消除不同组数据的量纲差异,确定各组数据的客观权重,计算各方案的相对贴合度,从中选出备选材料;使用正交试验设计和极差分析将备选材料与电池箱不同板件进行匹配,得到多材料电池箱,对多材料电池箱进行尺寸优化。优化后的电池箱模型在满足强度、刚度和低阶模态频率等要求的基础上减重5.3 kg,减重率达11.37%。

As the battery box goes lightweight,suitable lightweight materials are selected to match the panels at different positions of the battery box and take full advantage of material properties.In this paper,the TOPSIS method based on CRITIC weight and orthogonal test is employed.First,the decision-making matrix of the properties of commonly used metal materials in battery boxes is built,and the TOPSIS method based on CRITIC weight is employed to standardize the processing,eliminate the dimensional differences of different groups of data,determine the objective weight of each group of data,calculate the relative fit of each scheme,and select alternative materials.Then,the orthogonal experimental design and range analysis are employed to match the alternative materials with different plates in the battery box,and a multi-material battery box is created.Finally,the size of the multi-material battery box is optimized.The optimized battery box model reduces weight by 5.3 kg with a weight reduction rate of 11.37%while meeting the requirements of strength,stiffness and low-order mode frequency.