Yu Wancheng, Wei Zhenyao, Wang Lei, Shang Jian, Xu Hailong, Luo Yufeng, Cai Jiehua, Xie Chuan, Guo Yanpeng, Zhou Junhua, Deng Yonghong, Huang Qiyao, Zheng Zijian
Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, SAR, 999077, China.
Laboratory for Advanced Interfacial Materials and Devices, School of Fashion and Textiles, The Hong Kong Polytechnic University, Hong Kong, SAR, 999077, China.
Adv Sci (Weinh). 2025 Sep 23:e13494. doi: 10.1002/advs.202513494.
Current collectors are indispensable components in flexible lithium batteries. However, commercially used current collectors are heavy and rigid, severely limiting the energy density and flexibility of the batteries. Metallic polyethylene terephthalate fabrics (MPETs) have emerged as promising alternatives due to their lightweight nature, low cost, and excellent flexibility. Despite these advantages, the chemical and electrochemical stability of MPETs under battery operating conditions remains largely unexplored. Herein, the rapid degradation mechanism of MPETs in working batteries and propose effective surface-stabilization strategies to enhance their long-term stability is systematically investigated. An electroplating-repair method is developed to fabricate etching-proof MPETs for anodes, and a phosphorus-incorporated nickel coating on PET to achieve high-voltage-stable MPETs for cathodes. Compared to commercial metal-foil current collectors, the surface-stabilized MPETs are significantly lighter -by 72.0% for the cathode current collector and 35.7% for the anode current collector, resulting in a 20% increase in battery energy density. FLBs assembled with these advanced MPETs exhibit outstanding cycling stability and maintain consistent voltage output even after thousands of bending cycles at radii as small as 1 mm. These results highlight the potential of surface-stabilized MPETs to enable the next generation of energy-dense and mechanically robust flexible lithium batteries.
集流体是柔性锂电池中不可或缺的组件。然而，商业上使用的集流体笨重且刚性大，严重限制了电池的能量密度和柔韧性。金属化聚对苯二甲酸乙二酯织物（MPET）因其重量轻、成本低和出色的柔韧性而成为有前景的替代材料。尽管具有这些优点，但MPET在电池工作条件下的化学和电化学稳定性在很大程度上仍未得到探索。在此，系统地研究了MPET在工作电池中的快速降解机制，并提出了有效的表面稳定策略以提高其长期稳定性。开发了一种电镀修复方法来制造用于阳极的防蚀刻MPET，并在PET上制备含磷镍涂层以实现用于阴极的高压稳定MPET。与商业金属箔集流体相比，表面稳定的MPET明显更轻——阴极集流体轻72.0%，阳极集流体轻35.7%，从而使电池能量密度提高20%。用这些先进的MPET组装的柔性锂电池表现出出色的循环稳定性，即使在半径小至1毫米的情况下进行数千次弯曲循环后仍能保持一致的电压输出。这些结果突出了表面稳定的MPET在实现下一代能量密集型和机械坚固的柔性锂电池方面的潜力。
