电动汽车锂离子铝壳激光焊接气孔控制方法

Porosity control method for laser welding of lithium ion aluminum shell ofelectric vehicle

在电动汽车锂离子电池铝壳激光焊接过程中,由于高温作用,焊接区域内的气体容易转化为蒸汽,从而形成气孔。为此,提出电动汽车锂离子铝壳激光焊接气孔控制方法。分析激光焊接线能量、脉冲频率以及激光占空比对焊缝气孔的影响。利用多输出高斯过程,求取模型的近似函数,以此构建电动汽车锂离子电池铝壳激光焊接气孔控制参数模型。基于直接学习机制,采用改进蚁群算法求解该模型,获取焊接工艺参数的最优解,实现对焊接气孔的控制。实验结果表明,所提方法在350 s时的脉冲频率为47 Hz,且运行时间仅为20.97 s,具有较好的控制效果和稳定性,能够实现电动汽车锂离子铝壳激光焊接气孔控制,具有较高的效率。

During the laser welding of the aluminum shell of the lithium-ion battery for electric vehicles,due to the high temperature,the gas in the welding area is easy to be converted into steam,thus forming pores.For this reason,a method of controlling porosity in laser welding of lithium ion aluminum shell of electric vehicle is proposed.The influence of laser welding process parameters(laser welding line energy,pulse frequency,and laser duty cycle)on the weld porosity of the lithium-ion aluminum shell of electric vehicles was analyzed.The approximate function of the model was obtained using the multi-output Gaussian process to build the parameter model for controlling porosity in laser welding of the aluminum shell of lithium-ion batteries for electric vehicles.The model was solved using the improved Ant colony optimization algorithms based on the direct learning mechanism to obtain the optimal solution for welding process parameters and achieve control over welding porosity.The experimental results show that the pulse frequency of the proposed method is 47 Hz at 350 s,and the operation time is only 20.97 s,which shows that the proposed method has good control effect and stability,and can realize the control of pores in the laser welding of lithium ion aluminum shell of electric vehicles,with high efficiency.