Composite foil, preparation method thereof and electrode plate comprising composite foil

The invention relates to the technical field of lithium ion batteries, in particular to a composite foil, a preparation method thereof and an electrode plate comprising the composite foil. The composite foil is sequentially provided with a first metal coating, a first polymer layer, a first bonding layer, a substrate layer, a second bonding layer, a second polymer layer and a second metal coating in a stacked mode. According to the whole structure of the composite foil material, the resistance of the battery adopting the composite foil material is reduced on the basis of ensuring the anti-needling safety, and the battery performance and the rate capability are obviously improved. 本发明涉及锂离子电池技术领域，具体涉及一种复合箔材及其制备方法和包含该复合箔材的电极片，所述复合箔材为多孔结构，所述复合箔材依次层叠设置有第一金属镀层、第一聚合物层、第一粘合层、基底层、第二粘合层、第二聚合物层和第二金属镀层。复合箔材的整个结构使得采用该复合箔材的电池在保证防针刺安全性的基础上降低电阻，电池性能和倍率性能明显提高。