锂离子动力电池极片的激光切割分析

为适应锂离子动力电池行业发展需求,寻求一种高效高质切片方式,本文研究了多种激光器的切片质量。通过影像测量仪和扫描电镜(SEM)对比发现,100 ns脉宽调Q型1 064 nm光纤激光器切割正极铝箔时毛刺和热影响区(HAZ)约为15μm和60μm,切负极铜箔时HAZ约为200μm; 20 ns脉宽的MOPA光纤激光器切割铝箔毛刺10μm,HAZ约为20μm,切铜箔时HAZ约70μm;脉宽为10 ps的固体激光器切割铝箔毛刺和HAZ分别约为6μm和10μm,切铜箔时实现无熔融重凝区; 20 ns脉宽的355 nm紫外和532 nm的绿光固体激光器切割铝箔HAZ分别为10μm和17μm,切铜箔时HAZ则分别为大于70μm和100μm。实验结果表明:脉宽越窄,重复频率越高,切割的极片质量越好,ps激光器切割的极片精度最高,质量最好,是切割极片最理想激光器。而目前,频率高、脉宽相对窄的MOPA光纤激光器切割速度最高,切割的正极片完全满足工业要求,更适合极片切割的工业推广。

Analysis of laser cutting of lithium-ion power battery pole piece

In order to meet the demand of lithium-ion battery industry, and to seek a high-efficiency and high-quality cutting method, the cutting quality by various lasers are investigated. Comparing with the image measuring instrument and SEM, it is found that the burr and heat-affected zone(HAZ) of aluminum foil cut by Q-type 1 064 nm fiber laser with 100 ns pulse width are about 15 μm and 60 μm, and the HAZ of negative copper foil is about 200 μm, the burr and HAZ of aluminum foil cut by MOPA fiber laser with 20 ns pulse width are 10 μm and 20 μm, respectively, and the HAZ of copper foil is about 70 μm. The burr and HAZ of aluminum foil cut by 10 picoseconds pulsed solid laser are about 6 μm and 10 μm separately, a zone of no melting and re-condensation is achieved when copper foil is cut. The HAZ of aluminum foil are about 10 μm and 17 μm respectively when they are cut by 355 nm UV and 532 nm green solid lasers with 20 ns pulsed width. However, the HAZ are more than 70 μm and 100 μm when cutting copper foil. The experimental results show that the narrower the pulse width and the higher the repetition frequency, the better the cutting quality of pole piece. The PS laser cuts the pole piece with the highest precision and the best quality, which is the most ideal laser for cutting the pole piece. At present, the MOPA fiber laser with high frequency and relatively narrow pulse width has the highest cutting speed, and the cut positive electrode piece fully meets the industrial requirements, and is more suitable for the industrial promotion of the pole piece cutting.