电池箱精细化有限元模型
Finite-element model of battery box finite-element
目前已有的研究大部分采用质量点模拟电池组，虽然建模速度快，计算时间少，但是电池组对箱体冲击力并不是均匀分布在箱体上，箱体变形并不符合实际。因此，有必要建立考虑电池箱内部电芯、托架及BMS等电气附件的精细化有限元模型。电池组内部有许多电芯、压板、隔板、电芯连接片、模块连接片、固定螺栓，结构十分复杂，考虑到仿真的难度和准确度，该精细化电池箱模型主要体现在以下方面：
Most of the existing research uses mass point simulation battery group, although the modeling speed is fast and the time of calculation is few, but the impact force of the battery pack is not evenly distributed on the box body, and the deformation of the box is not in line with the actual condition. Therefore, it is necessary to establish a refined finite element model considering the electrical accessories inside the battery box, bracket and BMS. In the battery pack, there are many electric core, press plate, partition board, electric core connection piece, module connection piece and fixed bolt. The structure is very complex. Considering the difficulty and accuracy of simulation, the model of the fine battery box is mainly reflected in the following aspects:
1、电芯数量过多，考虑到建模的时间、计算量、接触面，将12个电芯组成的电池组视为一个实体，传力的大小和路径比质量点更精确；
1, the number of electric cores is too much. Considering the time of modeling, the amount of calculation and the contact surface, the battery group composed of 12 electric cores is regarded as an entity, and the size and path of the transmission force are more accurate than the mass point.
2、保留电池组主要的传力部件，例如上压杆、内压杆、固定螺栓和外壳，保证电池组的惯性冲击力按精确的路径作用到箱体底板；
2. Keep the main force transmission parts of the battery group, such as the upper pressure bar, the internal pressure bar, the fixed bolt and the shell, to ensure that the inertial impact force of the battery group acts on the box floor according to the exact path.
3、考虑电池组与底板、压杆与电池组之间的接触非线性，保证电池组的惯性冲击力按精确的大小作用到箱体底板。
3. Considering the contact nonlinearity between the battery group and the bottom plate, the pressure bar and the battery group, the inertial impact force of the battery pack is acted on the box floor by the exact size.
4、简化程度低，仅仅忽略对静强度影响不大的电芯连接镀镍铜片、模块连接片等。
4, the degree of simplification is low, and only the nickel plated copper strip and module connecting piece with little influence on static strength are ignored.