电动汽车动力电池壳体力学特性研究

针对电动汽车动力电池的安全问题,本文基于ANSYS建立了电动汽车动力电池壳体力学分析的有限元模型,通过模态分析得出单体电池壳体的前5阶固有频率及振型,并利用有限元分析软件ANSYS中的LS-DYNA跌落模块,对电池壳体的有限元模型进行跌落仿真,仿真结果表明,电池从1.5m高度自由跌落时的最大应力为314MPa,电池壳体材料的屈服应力为685MPa,安全系数取1.5,故电池壳体的许用应力为456MPa,说明电池壳体跌落时的最大应力明显小于电池壳体的许用应力,因此,在电动车出现碰撞等事故时电池壳体不会发生屈服变形。该研究为电池结构的强度和刚度设计提供了理论依据,具有广阔的应用前景。

Study of Mechanical Characteristics on Electric Vehicle Power Battery Shell

Aiming at power battery safety problem of electric vehicle, this paper establishes the finite ele- ment model of mechanical characteristics on electric vehicle power battery shell. Through modal analysis, we get the first five natural frequencies and vibration modes of the battery shell. It also analyzes the drop feature of the battery shell. The results show that the maximum stress of the battery shell is 314 MPa when the battery shell drops freely from the 1.5 m height, the material of battery shell yield stress is 685 MPa and the safety coefficient is 1.5. So the allowable stress is 456 MPa which is significantly more than the maximum stress 314 MPa. In conclusion, if collision accidents should occur, battery shell would not yield deformation. This study provides theoretical basis for the design of battery structure stiffness and strength. It will play an important role in the safety problem of power batteries for electric vehicles, and it also has broad application prospect in the field of electric gehicles.