锂电池钢壳缩口工艺的有限元仿真

Finite Element Simulation for Steel Case’s Shrinking Technic of Lithium Battery

钢壳缩口是圆柱锂电池制程中段的一道关键工艺,目标是将入壳工艺后的钢壳缩口,以免内部结构脱出。缩口过程涉及影响因素多,变形过程复杂。文章以有限元仿真为工具,采用隐式求解算法,对钢壳缩口过程进行动力学仿真。完整模拟缩口工艺过程,获得钢壳的变形和回弹,指导夹具的动作时序优化和初始公差设定。确定导杆的受力和变形情况,校验工艺过程中的安全性。仿真结果表明,夹具松弛后,钢壳会有0.02 mm的回弹,夹具工作面设置+0.02~+0.04 mm的公差可抵消部分回弹量。导杆在整个过程中最大受力为2 738 N,无安全风险。该方法将缩口工艺过程可视化,为优化工艺参数提供了重要指导。

Steel case’s shrinking is an important technic in middle manufacture process of cylindrical lithium battery aiming to shrink the case after insertion technic in case of escape of interior structures.With tool of finite element simulation,implicit solution is adopted to perform dynamic simulation for case’s shrinking process.Based on a complete simulation of shrinking technic process,deformation and resilience of the case is acquired so as to guide time-sequence optimization and origin tolerance settings of the fixture.Stress and deformation of the guider-bar is acquired to check the security of the technic process.The simulation result shows a resilience of 0.02 mm for the steel case.A tolerance of+0.02~+0.04 mm is recommended to counteract the resilience partially.Max force of the guider-bar during the whole process is 2738 N and no security risk is found.The proposed method visualizes the shrinking technic process and provides important guidance to optimizations of technic parameters.