软包装锂离子电池用铝塑膜材料研究进展

Research Progress of Aluminum Plastic Film for Soft-Packaging Lithium-Ion Batteries

随着锂离子电池的发展,对高性能电池封装材料的需求持续推动着软包装材料的技术研究。铝塑膜重量轻、厚度小,能实现更高的电池容量和能量密度,是软包锂离子电池的重要封装材料。然而,铝塑膜在耐电解液腐蚀,冷冲压成型和热封抗撕裂等方面性能仍有待进一步改善。如果能从原材料和制备工艺出发,提出克服这些不足的方案,可帮助国产铝塑膜尽快完成进口替代,实现弯道超越。本文首先综述了铝塑膜的结构、性能标准,重点讨论了铝塑膜的结构发展历程及各层材料的基本特点与作用;其次介绍了铝塑膜的制备工艺及其应用于锂电池的封装工艺;然后针对铝箔表面处理、冲压深度、热封强度等方面,分别探讨了当前铝塑膜在铝箔钝化与掺杂、粘合剂改性以及工艺改良的研究进展,最后对当前铝塑膜的产业的现状做出分析与展望。

With the development of the lithiumion batteries (LIBs), the increasing demand for high-performance LIBs encapsulation has insistently motivated the research of soft packaging material. Aluminium plastic film is of great importance for pouch LIBs packaging, owing to its excellent lightness and the potential to enhance capacity and energy density of LIBs. However, the properties of aluminum plastic film, such as electrolyte corrosion resistance, cold stamping quality and tearing resistance of heat sealing, still need to be further improved. To overcome these shortcomings and accelerate the independence of the aluminium plastic film in China, solutions originating from raw materials and techniques are urgently requested. In this paper, the structure and performance standards of aluminum plastic film were reviewed, focusing on the structure development and the basic functions of each layer. The manufacturing process of aluminum plastic film and its application in LIBs packaging were also introduced. Based on the aluminum foil surface treatment, stamping depth as well as heat sealing strength, the current progress of foil passivation and doping, adhesive modification and process optimization of aluminum plastic film were discussed. Finally, the present status of aluminum plastic film industry has prospected.