Lithium-ion battery is an efficient energy storage device and have been widely used in mobile electronic devices and electric vehicles. As an indispensable component in lithium-ion batteries (LIBs), copper foil current collector shoulders the important task of collecting current and supporting active materials, and plays a pivotal role in promoting the development of high-performance lithium-ion batteries. Compared with traditional electrolytic copper foil, composite copper foil with a distinctive "Cu-polymer-Cu" sandwich structure significantly reduces the weight of current collector and increases the energy density of battery. In addition, the transverse insulated and flexible polymer interlayer can block heat diffusion and alleviate the expansion stress. Therefore, the safety and cycle performance of lithium-ion battery can be improved. In this review, the requirements of copper foil collectors, the characteristics of polymer interlayer, the advantages of composite copper foil and the preparation methods of composite copper foil are introduced. Aiming at the weak bonding force between copper and polymer in composite copper foil, the improved methods to enlarge the bonding force are summarized. With the emphasis on the key perspectives, the paper will provide valuable inspiration for the rapid development of composite copper foil to advance high-energy density lithium-ion batteries.

中文翻译：

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具有三明治结构的复合铜箔集流体，用于高能量密度和安全的锂离子电池


锂离子电池是一种高效的储能装置，已广泛应用于移动电子设备和电动汽车。铜箔集流体作为锂离子电池 （LIB） 中不可或缺的部件，肩负着收集电流和支撑活性材料的重要任务，在推动高性能锂离子电池的发展中发挥着举足轻重的作用。与传统的电解铜箔相比，具有独特的“Cu-Polymer-Cu”夹层结构的复合铜箔显著减轻了集流体的重量，提高了电池的能量密度。此外，横向绝缘和柔性聚合物夹层可以阻止热扩散并减轻膨胀应力。因此，可以提高锂离子电池的安全性和循环性能。本文对铜箔集热器的要求、聚合物夹层的特点、复合铜箔的优点以及复合铜箔的制备方法进行了综述。针对复合铜箔中铜与聚合物结合力较弱的问题，总结了扩大结合力的改进方法。本文强调关键视角，将为复合铜箔的快速发展以推进高能量密度锂离子电池提供有价值的启发。